ML20112B574
ML20112B574 | |
Person / Time | |
---|---|
Site: | Arkansas Nuclear ![]() |
Issue date: | 12/05/1984 |
From: | ARKANSAS POWER & LIGHT CO. |
To: | |
Shared Package | |
ML20112B557 | List: |
References | |
PROC-841205, NUDOCS 8501100461 | |
Download: ML20112B574 (521) | |
Text
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t ARKANSAS .N U C L E A R- 0NE
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- lj EMERGENCY OPERATING PROCEDURE
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. r TECHNICAL GUIDELINES li WP84989 I
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,f- TABLE OF CONTENTS -
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SECTION PAGE I.. REFERENCES . . . . . . . . . . .. . . .. . .. . . ..... . . I-1 II.s INTRODUCTION . . . . . . . .. . .. .. .. . .. .... .. . . II-1 1.0 PURPOSE:.. . . . . . . . . . .. ... . .. .. .... . . . II-1
' 2.'O BACKGROUND . . - . . . . . .. .. .. ... ...... . . II-1 III.' VERIFICATION AND VALIDATION DESCRIPTION . . ....... . . . III-1 IV. TECHNICAL DEVELOPMENTS AFFECTING
~ EMERGENCY OPERATING PROCEDURES . . ... . . ... . . ... . . IV-1 1.0 PRESSURIZED THERMAL SHOCK . . . .. . . .. . .. .... . IV-1 2.0 ' INADEQUATE CORE COOLING . .. . . .. . . . . . . . . . . . IV-6.
- 3.0 RCS VOIDING . . . . . . . . . . . . . .. . .. ..... . . . IV-9 4.0i REACTOR COOLANT PUMP (RCP) TERMINATION '
AND RESTART CRITERIA . . . . . .. . . . . . . . . . . . . . IV-16 5.0 HIGH PRESSURE SAFETY INJECTION (HPSI) TERMINATION ,
AND RESTART CRITERIA . . .. . . . . . . ....... . . IV-20 V. EMERGENCY OPERATING PROCEDURES DEVELOPMENT . ... . . . . . . . V-1 1.0 DEFINITIONS . . . . . .. . .. .. ..... . ..... . . V-1 2.0 INTEGRATION OF SAFETY FUNCTION CONCEPT .. ....... . .V-3 4 3.0 FORMAT . . . . . . . . . . . .. .... .. . . . . . . . V-7 4.0 CONTENT'0F E0Ps . . . . . .. . . . . - . . . ..
. . . .-. . V-9 5.0 PRINCIPLES OF EOP USE . . . . .. . . . .. .~. . . . . . . V-12 VI. . BASES FOR ENTRY CONDITIONS AND IMMEDIATE ACTIONS . ..... . . VI-1 1.0 ENTRY. CONDITIONS . . . . . . . . . ... . . . . . . . . . . VI-1 2.0 -IMMEDIATE ACTIONS . . . . . . . . . . . .. ...... . . VI-2 *
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t TABLE OF CONTENTS SECTION PAGE VII. BASES FOR RECOVERY GUIDELINES TABS . ..... . . . . . . .. . VII-1.0-1 1.0 REACTOR TRIP RECOVERY ACTIONS . ..... ... ... . . . VII-1.0-1 2.0 EMERGENCY REACTIVITY CONTROL ACTIONS .. ... . .. . . . VII-2.0-1 3.0 DEGRADED POWER RECOVERY ACTIONS . .... . . . . . . . . . VII-3.0-1 4.0 BLACKOUT RECOVERY ACTIONS. .
. . .... ... .. . . . . VII-4.0-1 5.0 OVERC00 LING RECOVERY ACTIONS. .. .... ... ... . . . VII-5.0-1 6.0 MAIN STEAM ISOLATION ACTIONS. .. . ... . . . ... . . . VII-6.0-1 7.0 SAFETY INJECTION ACTUATION RECOVERY ACTIONS . . . .. . . . VII-7.0-1 8.0 S/G TUBE RUPTURE WITHIN CHARGING PUMP CAPACITY RECOVERY ACTIONS . . . . . . . . . . . .. ........ ...
. . VII-8.0-1 9.0 S/G TUBE RUPTURE GREATER THAN CHARGING PUMP CAPACITY RECOVERY ACTIONS . . . . . . . . . . . . . . . . . . . . . VII-9.0-1 10.0 INADEQUATE CORE COOLING RECOVERY ACTIONS . ... .. . . . VII-10.0-1 c
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. I.- REFERENCES O A. This technical guideline document was developed using the following plant specific and generic NSSS source documents with attention paid to acquiring the most current information possible.
- 1. ANO-2 FSAR
- 2. . ANO-2 Technical Specifications
- 3. ANO-2 Current-EOPs
- 4. ANO-2 Piping Instrumenta*. ion and Electrical Drawings
- 5. CEN-128, " Response of Combustion Engineering Nuclear Steam Supply Systems to Transients and Accidents"
- 6. INPO Document 83-0007, " Emergency Operating Procedures Generation Package Outline"
- 7. CEN-153, " Response of Combustion Engineering Nuclear Steam Supply System to Transients and Accidents with Multiple Failures"
- 8. CEN-114, " Review of Small Break Transients in Combustion Engineering Nuclear Steam Supply System"
- 9. CEN-154, " Natural Circulation Cooldown"
- 10. .CEN-268, " Justification of Trip Two/ Leave Two RCP Trip. Strategy During Transients"
- 11. NRC Generic Letter 83-10b, " Resolution of TMI Action Item
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II.K.3.5"
- 12. CEN-117, " Inadequate Core Cooling - A Response to NRC IE Bulletin 79-06C, Item 5."
- 13. M-2017, Containment Spray Pump Technical Manual O
WP84989 SECTION I PAGE 1 n+.
II. INTRODUCTION 1.0. PURPOSE The purpose of this document'is-five-folds A) Provide the methodology of the ANO-2 EOP development, content and use.
B) Provide technical information, derived from engineering resources, to identify operational concerns and to aid the EOP writer / reviser with resource material.
C) Briefly describe the validation and verification process used for the ANO-2 EOPs as guidance for any future changes / revisions.
D) Provide the basis behind each EOP step to assist in EOP evaluation /
revision and operator understanding / training.
E) Satisfy the requirements of NUREG 0737, Item I.C.1.
2.0 BACKGROUND
Plans for the upgrade of the ANO-1 and 2 emergency operating proce-dures began in the summer of 1979 following an evaluation by AP&L of the THI-2 accident. The initial thrust of this effort was directed at ANO-1 emergency operating procedures. The ANO-1 EOPs were developed
'with human factors in mind and are function oriented to improve human reliability and the ability to mitigate the consequences of a broad range of initiating events and subsequent multiple failures or operator ,
errors without the need to diagnose specific events. In an effort to maintain consistency between the emergency procedure approaches taken on ANO-1 and ANO-2, emergency procedures for ANO-2 will be
-written with a similar procedural structure and approach as those for ANO-1. The ANO-2 procedures are, of course, based on technical data applicable tio ANO-2. This document provides plant specific W84989 SECTION II ,PAGE 1 e
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7 technical guidelines for ANO-2 which when combined with the ANO-1 E0P
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-writing guidance, validation program description and training program description will comprise the ANO-2 procedure generation package.
Details of the validation program and training program may, vary some-what for application to ANO-2 (e.g., validation scenario-list).
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- III.. VERIFICATION AND VALIDATION DESCRIPTION
- f. f f' ' ..The purpose of this section is to remind the reviser of the ANO-2 EOP of the verification and validation processes used to ensure the correctness V; iof the'ANO-2 EOP. It is'not intended to describe these processes in detail
- nor-provide validation and verification program guidance.
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-The validation program objective is to ensure the control room operators ,
can manage emergency conditions in the plant using the EOP. This is y ensured by the application of validation principles for usability and -
operational. correctness. Evaluation of usability ens'ures that the ECP '
provide. sufficient and understandable operator information. Evaluation iof operational correctness ensures that the EOP are. compatible with plant responses,planthardware,andtheshiftmanpower./Validationmethods' may include reference material authenticity, round table discussion, b actual operator walkthrough, or simulator testirig of the EOP.
.The verification program objective is to ensure written correctness and technical accuracy. Written correctness ensures info'rmation is
, incorporated into the EOP using proven human factors guidance and' plant specific administrative guidelines. Technical accuracy ensures proper incorporation of generic and plant specific technical information.
Operator input into both these processes (verification and validation) is
' invaluable in ensuring the appropriateness of the E0P as they are the end user of this' product and the individuals who must ultimately implement 1
the E0P should the need arise.
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E0P verification addresses whether the E0P is written correctly and is technically accurate. E0P validation addresses'whether.the E0P is usable by the operator and operationally correct. These processes should be completed prior to implementation of the E0Ps.
After implementation, any future revisions should undergo the verification
'and validation processes to maintain consistency to original document.
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~ IV.' . TECHNICAL ISSUES AFFECTING. EMERGENCY PROCEDURES-C, '
Several. technical ' issues have already, or may in the future, effect the upgrade program of.the ANO-2 EOP. Five such issues have been identified for.immediate incorporation into the ANO-2 E0P. They are:
-1.0 Pressurized. thermal shock 2.0 Inadequate core cooling 3.0 'RCS. voiding 4.0 Reactor coolant pump termination and restart criteria 5.0 HPSI termination and restart criteria
. Any future technical developments, NRC or operational concerns that may affect the ANO-2 EOP will be addressed as .such issues arise.
1.0 Pressurized Thermal' Shock (PTS)
'This NEC concern deals with the potential for thermal shock of the reactor vessel resulting from uncontrolled cooldown and/or cold safety,
-injection flow' and possible non-ductile failure of' the reactor. vessel -
upon repressurization. While this is not an immediate concern at
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1ANO-2 due to metallurgical characteristics:of the.RCS,, operator awareness of this issue is necessary to prevent-undue stress on RCS.
components.
Typically, a PTS transient is characterized by a rapid uncontrolled-RCS cooldown and depressurization followed by a repressurization.
The thermal shock transient combined w'ith'the RCS repressurization will cause thermal and pressure stresses which could result in crack initiation within the reactor vessel. The degree to which any reactor vessel would be affected by a PTS transient depends on the WP84989 SECTION IV PAGE 1 e
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- w physical strength properties and neutron induced embrittlement of.the vessel, pre-existing flaws in the vessel, and the severity of the
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. transient.
- Steam.line breaks are of particular concern because of the severity of the cooldown phase. In general, a PTS situation may occur any.
' time 'an overcooling transient is followed or accompanied by a high RCS pressure.
The operator goals during a PTS transient are first, to control
, the overcooling transient where possible and second, to limit the repressurization of the RCS. Primary emphasis must ultimately.
be placed on prevention of excessive pressurization since the initial cooldown transient is'not always controllable and the cooldown thermal stresses alone will not violate the pressure boundary.
The potential for PTS of a reactor vessel is reduced if the coolant
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temperature and pressure are maintained within acceptable' limits. In the case of PTS, the concern arises'in situations where a low tempera-ture has occurred due to cooldown in excess of Technical Specification-rate limits accompanied by a high pressure. A convenient way to define acceptable combinations of low' temperature and high pressure is to define an upper limit on coolant subcooling.. Since we are also concerned about minimum subcooling, the combination of upper and lower' O
WP84989 SECTION IV PAGE'2 e
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. :. subcooling limits is used to define a band of pressure and temperature ]
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' conditions within which the RCS should be maintained. The upper and lower'subcooling limitations are addressed on graphs. incorporated into the ANO-2 EOP and on the Safety Parameters Display System (SPDS) graphic display pressure temperature (P/T) curve.
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4 The lower limit on subcooling assures that subcooled fluid surrounds the reactor core as one of the requirements of adequate core cooling.
If subcooling cannot be maintained, the E0P instructs that high pressure safety injection (HPSI) pumps must be operated until the -
coolant subcooling is sufficient and there are indications of adequate inventory.
PTS considerations dictate that the HPSI pumps and charging pumps be turned off when the pressurizer water level reaches some specified high value in order to avoid filling the pressurizer solid and overpressurizing the RCS.. However, instructions on maintenance of minimum subcooling for adequate core cooling should prevail over PTS
' considerations due to the much more severe consequences of inadequate core cooling to the integrity of the fuel pins. Therefore, the guidance calls for continued running of the HPSI pumps until 30'F subcooling is achieved regardless of pressurizer level. .
WP84989 SECTION IV PAGE 3 e
. An upper subcooling limit has been developed using engineering d) '
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. judgment based on existing plant thermal-hydraulic and fracture R
mechanics analyses. This upper limit of subcooling ia impoced any time the RCS~has experienced a cooldown rate in excess of TechnicalLSpecification limits for greater than ten minutes.
At ANO-2 a 200' maximum subcooling limit is used for indication of
. potential PTS conditions. This limit is graphically displayed and compared to RCS conditions by using the PT curves display on SPDS or to graphs incorporated in E0P's. This limit is judged to provide a-sufficient operating band for the operator while requiring the pres-sure stresses to be maintained at a safe level.
The upper limit was developed with the understanding that due '
h to the inability of.the operator to control the initial cool-
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dcwn transient in all cases, it is conceivable that the limit may be violated during the first part of the transient. The operator's goal is to restore the plant to the acceptable band of pressure and temperature as soon as possible. In general, this should be accomplished by depressurizing, either by using pressurizer sprays or by terminating or throttling HPSI or charging. This approach is acceptable since thermal stresses resulting from the initial transient will not breach the reactor vessel ~. Therefore, the operator's efforts are directed at j- depressurizing or preventing repressurization.
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1 To incorporate these goals into ANO-2 EOP, cautions of upper and lower h-- ..
, subcooling limits are provided to alert the operator to PTS conditions
-and remedial action steps provided along with referenced P/T graphs i' showing acceptable operating limits during potential-PTS transients. '
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- 2.0 Inadequate Core Cooling (D
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The subject of inadequate core cooling (ICC) has received much interest e
since TMI. During the TMI accident, there was a substantial period of time during which the reactor core was inadequately cooled, and the operators failed to take appropriate actions to correct the condition.
It is generally considered that sufficient instrumentation indications were available to recognize the ICC condition, but that the operator training and plant emergency procedures did not prepare the operators to recognize ICC and respond properly.
A major goal in the development of these technical guidelines for ANO-2 has been to provide guidance to maintain an adequately cooled core and to alert the operator if the actions being performed are
(~)g not effective. This goal has beer, schieved in a number of ways.
These are highlighted below. Explanations of.each are found elsewhere in this document.-
A. Criteria for stopping safety systems (e.g., ECCS) is included.
For example, the termination criteria for,the safety injection system (SIS) ensures that RCS inventory, pressure and heat removal meet specified conditions before the system may be overridden.
B. Each recovery guideline is built around a strategy which minimizes the likelihood of an inadequately cooled core.
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WP84989 SECTION IV PAGE 6 e'
C. Safety function status _ checks are provided to alert the operator if the actions being taken are ineffective or-
.' inappropriate, thus averting an ICC situation.
D. Studies have been performed to determine if instrumentation is
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' available to monitor the approach to, existence of, and recovery from ICC. It has been concluded that existing instrumentation is adequate to recognize ICC conditions but more direct indica-tions are desirable and are being pursued by the ANO-2 plant staff. As instrumentation becomes available for use, the ANO-2 EOP will be upgraded to incorporate this instrumentation in its safety function status checks and recovery actions.
The Core Exit Thermocouples (CETs) are the major indication used in the detection of ICC at the present time. The CETs are located a few inches above .the fuel alignment plate, thus above the active
' fuel. During normal operation, these CETs should read closely to and track with RCS hot leg temperature.
A discussion on instrumentation that can be used in determining ICC situations is provided in the ICC tab. ' Included in this are potential inaccuracies and misleading readings that may be obtained in accident situations.
In the majority of cases, multiple system failures must occur in order _ for situations to develop requiring entry into the ICC tab.
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,, - Inadequate core cooling occurs when the core is not covered by a
>,S'1-liquid or two phase mixture. The ultimate consequences of core uncovery are dependent upon the length of time that the uncovery lasts and the depth that the core is uncovered. Two separate conditions exist for the ICC tab. One entry condition addresses the CETs indicating that a superheat condition exists for the indicated pressure of the RCS. The other entry condition is a complete loss
-of feed to the S/Gs. This condition, if not corrected, will degrade
'into an ICC situation.
Core uncovery and the resulting indication of'superheat on the CETs indicates the onset of ICC conditions and is undesirable. If at anytime superheated conditions are indicated, the operator should review the effectiveness of the cooling medium now in use. Also, all possible steps should be taken *a -attore the ncs invantnry (racouar the core) and provide for core cooling as indicated by saturation o'r subcooling on the CETs and/or the Subcooled Margin Monitor.
Further detailed information is provided in the ICC tab.
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-3 q-r- -3.0 RCS Voiding '
f Voids in the RCS may be formed as-a result'of not maintaining pressure control and losing the minimum required subcooling margin. Those system conditions affecting void formation over which an' operator.may have control include the rate of RCS depres-
- surization, the rate of RCS cooldown, and flow distribution in the RCS . , Depressurization and cooling relate.to the state (amount of
'subcooling) of the RCS fluid. Loss of subcooling leads to a saturated condition which relates to the formation of voids in the RCS. Flow distribution refers to the fact.that the fluid state in all parts of, the. RCS may not be uniform if there is inadequate flow in some regions. Thus, a loop in which the steam generator is isolated when no reactor coolant pumps (RCPs) are running may'be at higher tempera-tures than the rest.of the RCS if a cooldown is in progress. Similarly, the , temperatures in the reactor vessel head region may be higher than the rest of the RCS since there is little exchange of' fluid between the head region and other parts of the RCS without the RCPs running.
The potential for RCS voiding exists during normal operating transients,
- natural circulation cooldown and accidents. During normal operating-
. transients, voids in the RCS are highly unlikely since the proper.
operation of the pressurizer p. essure control system should maintain the subcooling margin.
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~ As discussed above, a natural circulation cooldown may result in reactor vessel upper head voiding or stagnate loop voiding. Main-taining subcooling with respect to hot leg temperature when RCPs are running will generally prevent any portion of the RCS from voiding. However, RCS . voids may be formed while maintaining S/G heat removal in natural circulation for the following cases:-
t A. Depressurization during natural circulation'cooldown so that' .
- the stagnant reactor vessel upper head region reaches satura-tion.
B. An asymmetric natural circulation cooldown which results in stagnated flow in one steam generator loop (e.g., steam
, , generator isolated due to tube rupture or steam line break).
p c C. A loss of reactor coolant system pressure control which results i
in the loss of subcooling margin..
t In addition to natural circulation cooldowns,. accidents which result in rapid depressurization to saturation conditions throughout the RCS may result in some voiding'(eg., SLB, SGTR, LOCA). For large.
'LOCAs in which depressurization to very low pressures occurs rapidly and pressure control is not regained, voiding of the RCS is not a i
- concern as long as.the core is kept covered by the ECCS injection
' fluid. For small LOCAs (where S/G cooling is important'for heat removal), SGTR and SLBs (where the RCS is refilled by the HPSI and charging systems) voids may be present. Subcooling is reestablished by achieving pressure control with the-pressurizer heaters or by A
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pressurizing with the HPSI and charging systems. If RCPs are re-
.(9 started with'subcooling established, voids will be- eliminated much more quickly than under natural circulation conditions. If natural
. circulation is the mode of cooling, then voids may form or grow as discussed under natural circulation above.
Gas voids in the RCS may be formed by the accumulation of hydrogen
- and/or non-condensible gases. The largest potential source of gas (hydrogen) would result from the clad oxidation which could occur following long-term core uncovery. Gas pockets may also result from the release of dissolved gases in the reactor coolant during depres-surization. Another~ source of gas which might be significant is nitrogen cover gas in the safety injection tanks (SITS). Release of f - this nitrogen would only occur if the RCS had been depressurized by a large LOCA to low pressures where the size of the break would prevent RCS pressure recovery. In this case, core cooling is accomplished by ',-
boil off from the core and fluid replenishment from the Safety Injection System. Therefore, release of this nitrogen into the RCS would not be a problem.
Procedural guidance is provided to the operators for the detection and management of voids.
A. Voiding in the RCS may be indicated by the following parameter changes or trends:
- 1) With the pressurizer level control system (PLCS) in automatic,
'an increase in pressurizer level or letdown flow greater than
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WP84989 SECTION IV PAGE 11 e
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' charging flow during a decrease in RCS pressure, not attributable to an increase in RCS temperature.
- 2) With the PLCS in automatic, a decrease in pressurizer level or letdown flow less than charging flow during an increase in RCS pressure, not attributable to a decrease in RCS ter.perature .
- 3) With the PLCS in manual or with letdown isolated, an increase in pressurizer level during a decrease in RCS pressure, not attributable to an increase in RCS temperature.
- 4) With the PLCS in manual or with letdown isolated, a decrease in pressurizer level during an increase in RCS pressure, not attributable to a decrease in RCS temperature.
- 5) With the PLCS in manual or with letdown isolated, pressurizer
- q. level not increasing as expected when charging pump (s) are
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started or letdown flow is adjusted less than charging flow while maintaining a fairly constant RCS temperature.
- 6) With the PLCS in manual, pressurizer' level not decreasing as expected when letdown flow is adjusted greater than charging flow while maintaining a fairly constant RCS temperature.
- 7) Pressurizer level not increasing as expected when high' pressure safety injection flow is established.
The above RCS pressure changes may be accomplished by the use of pressurizer heaters, auxiliary spray or a change in pressurizer - level.
O WP84989.. SECTION IV PAGE 12 et L.
', . ) B. The following test can be performed by an operator to verify
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the absence of RCS voiding. If plant parameters do not respond
.as indicated, evidence of voiding exists and plant conditions should be analyzed to determine appropriate corrective action.
t This test is only valid for an intact RCS.
- 1) Establish manual control of pressurizer level and pressure and stabilize.
- 2) Start an additional charging pump and verify pressurizer pressure and level increase.
- 3) Energize additional heaters and verify pressurizer pressure increases and that level remains relatively constant.
- 4) Initiate pressurizer auxiliary spray and verify pressurizer pressure decreases and that level remains relatively constant.
If pressurizer parameters respond within the above criteria and subcooling is within the limits of the pressure / temperature (P/T) graph or SPDS graphic P/T display then significant voiding does not exist. If pressurizer parameters do not respond within the above criteria, then voiding is indicated, n
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WP84989 SECTION IV PAGE 13
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,_q C.. .It is not always -imperative that the operator take measures to d'
remove voids, if they are detected. Voids may be allowed to i
remain as long asLthe_ core heat removal, RCS heat removal and-the RCS ' inventory safe'ty functions are being satisfied.
I D. . Anytime it is found that either the core heat; removal, RCS heat.
removal or inventory control safety functions are not being satisfied, or voiding is causing the RCS to remain pressurized above SDC system entry pressure when SDC operation is desired,-
an attempt to eliminate the voiding must be made. Performance of void elimination is as follows:
, ' l) Verify letdown is isolated to minimize further inventory loss.
- 2) Stop depressurization to prevent growth of the void.
- 3) Repressurizing and depressurizing the RCS within the limits.
of the P/T graph or SPDS graphic PT display may condense-the void. Repressurizing has the effect of filling the voided portion of the RCS with cooler fluid which will remove heat from this region. Depressurizing'and repeating.
this process several times will cool and condense the steam void. The pressurizing and depressurizing may be accomplished using the pressurizer heaters'and auxiliary spray or the 4
ECCS/ charging system.
- 4) The reactor vessel head vent system may be operated to clear voids in the reactor vessel head. _This system will clear gas voids within minutes.
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- 5) One method for condensing steam voids or for removing
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non-condensible gases from the S/G tube bundle is to run RCPs (if available). If that is not possible, cooling the generator by feeding and bleeding (blowdown) or by steaming will also be effective for condensing steam voids in the tube bundle.
Cooling the steam generators will not have an effect on non-condensibles trapped in the tube bundle. A build-up of non-condensibles in the tube bundles will not hinder natural'
, circulation even with a large number of the tubes blocked.
1 This is because of the small amount of'S/G heat transfer f
area required for the removal of decay heat.
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, 4.0 Reactor Coolant Pump (RCP) Termination and Restart Criteria
-( 'l-The question of RCP termination has been the subject of considerable research since the THI accident. There are two main goals of the RCP termination criteria. The first goal is to ensure that all RCPs are tripped during a LOCA for which RCP trip is necessary. The second goal is to maintain forced RCS circulation for non-LOCA events.
C-E calculations show it is recommended to trip the RCPs for small break LOCAs in.the break size range from 0.02 ft 2 to 0.1 fta (Reference 10). The most limiting small break LOCA in this respect is a break in the hot leg. Tripping the RCPs minimizes the loss of RCS fluid inventory from breaks located in the hot leg.
It is desirable to maintain at least two RCPs operating (one in each loop) for non-LOCA transients such as steam line breaks (SLB), steam generator tube ruptures (SGTR) and anticipated operational occurrences (A00). This gives the operator more control using main pressurizer spray to cool down and depressurize the plant. Operating one or more RCPs during a non-LOCA event also results in the continuous mixing of fluid in the reactor vessel upper head, thereby minimizing the possibility of void formation in the vessel head. Additionally, forced circulation will provide better mixing in the reactor vessel downcomer/ lower plenum region minimizing pressurized thermal shock (PTS) concerns.
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v If the RCP termination criterion of pressurizer pressure s 1400 psia
.(:) is' reached,-two RCPs (one in each loop) are secured. This will result
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in two RCPs.being. tripped for any sizable depressurization event. The setpoint of s 1400 psia was chosen based on the fact that following a small break LOCA, the RCS pressure may stabilize at a pressure corresponding to the saturation pressure of the steam generators.
, .The trip setpoint must be: greater than this " pressure plateau" to
. ensure RCPs are tripped for a LOCA. Two RCPs are tripped for applicable depressurization events since it can be demonstrated that the plant can be maintained in a safe condition, regardless of
- event, with two RCPs running. The setpoint of s 1400 psie includes
-all expected instrument errors.
I Since all LOCAs for which RCPs need to be secured, 0.02 fta to 0.1
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used as the second RCP termination criterion. The use of RCS margin
- -to saturation as a RCP termination criterion, in conjunction with
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secondary radiation: indications,- should result in all RCPs being.
-secured on a LOCA~(requiring RCP-termination), and two RCPs left running on non-LOCA events. 'C-E steam line break analysis,.using.
best estimate ' assumptions (with the exception of moisture carryover)
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-show RCS margin to saturation.will not decrease to the RCP termination setpoint.(Reference 10). Therefore,.two RCPs are
'; expected to remain ~ running on any size SLB.
If indications of a
~SGTR areipresent (secondary radiation monitors increasing), two RCPs are left running even if the RCS margin to saturation' decreases to L
- WP84989 .SECTION IV1 PAGE 17-e.
e..
E_
7-q < 30*F. This is acceptable since RCS margin to saturation, if it
.(
i does decrease to < 30*F, is expected to be quickly restored, s
The RCP restart criteria has been chosen to ensure that the relevant i RCS conditions are under control and that RCP operation under these conditions will not be detrimental (e.g., result in undesirable j inventory loss).
RCP restart criteria are provided in Appendix H of the EOPs. This listing of criteria should ensure that all conditions necessary to I
restart a RCP are satisfied. The following is a listing of the RCP restart criteria:
n, 0
4
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5/
A. Verify at least one S/G is available to remove heat from the RCS.
B. Verify pressurizer level'is 2 29% but s 82%.
C .' Verify RCS margin to saturation is 2 30*F. -
D. Verify RCP start interlocks are satisfied: ,
i
- 2. RCP cooling water discharge flow low alarm is not in.
~
E. Verify RCP operating curves, per Figure 1, are satisfied.
11 F. To start a fourth RCP,' verify RCS temperature (T C} '
- G. Verify proper seal staging.
H. Verify C.B.O. flowpath available: '
- 1. C.B.O. isolations to-VCT (2CV-4846-1 AND 2CV-4847-2) open.
SE 1
/~'T' 2. C.B.O. relief' isolation to quench tank (2CV-4856) open.
V.
_EP84989 SECTION IV PAGE 18 4
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- I~. Verify RCP.. reverse rotation alarm'is not in..
-Verify RCP motor starting limits'are satisfied:
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The motor can be started once s from' rated motor temperature. -
3
' Since there are no indicat' ions of both rotor and stator -l
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- rated temperature after being' idle for 200 minutes, or. running -O I - for 60 minutes', after its last start.
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. SECTION IV PAGE 19 d
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5.0 High Pressure Safety Injection (HPSI) Termination and Restart Criteria (J' Once the HPSI system has been actuated, the operator must have guidance which prevents premature termination of HPSI (i.e., before inventory control, pressure control and subcooling margin in the RCS is regained) but permits stopping HPSI before the RCS is overfilled possibly resulting in RCS overpressurization.
Overpressurization refers not so much to reaching an RCS safety setpoint, but rather to pressurized thermal shock (PTS) considerations.
These considerations require that the repressurization which might result from HPSI and/or charging pump operation should be minimized to avoid the range of reactor vessel (RV) stresses which contribute to PTS. A post-accident P/T limit curve is provided in the ANO-2
/
E0P and on the SPDS graphic PT display which, if observed; is judged b"%
to lead to safe plant conditions. This curve prescribes that the RCS be operated between a lower and upper subcooling limit after an overcooling. transient. The ANO-2 EOP maximum subcooling limit will provide an adninistrative limit that will minimize the reactor vessel pressure stress and provide indication of potential PTS conditions.
The guidance for HPSI termination is:
If at any time HPSI is operating, it may be throttled or stopped, one t
train at a time, if ALL of the following criteria are satisfied:
A. RCS'is subcooled in accordance with the P/T limit curve.
B. Pressurizer level is > 29% but < 82% and constant or increasing.
p.
.WP84989 SECTION IV PAGE 20
C. At least one S/G is available (feed and steam flow) for removing
.(-
' }
heat from the RCS.
Of these criteria, subcooling is most important'and should be the key parameter in making decisions on overriding SIS actuated components. The bases for these criteria are as follows:
A. Subcooling is an~ indication that RCS pressure and inventory are under control and that the fluid around the core is in a suitable state for RCS heat removal through the S/G(s).
B. ' Pressurizer level controlled in conjunction with the sub-cooling limits indicate that RCS conditions are such that single phase core cooling is possible and the RCS inventory is under control.
C. S/G availability is necessary for forced or natural circulation core cooling.
The restart criteria are based on RCS pressure, inventory, and heat
- removal not being adequately controlled. If the criteria above cannot be maintained after the HPSI system has been stopped, the HPSI system must be restarted.
un WP84989- SECTION IV PAGE 21 e
p,y.,- ,,e,-
.. , V. EMERGENCY OPERATING PROCEDURES DEVELOPME T 1.0 Definitions
~
A. Safety Function A' safety function is a condition (s), the attainment of which is needed to either prevent core damage or minimize radiation releases to the general public. If all safety functions are fulfilled, the safety of the public is assured.
B. Immediate Actions specific indications and actions which must be immediately observed or performed by control room operators to satisfy critical safety functions when a reactor trip is actuated or required.
C. Recovery Guidelines r^3 The recovery guidelines provide plant specific guidance which the V
operator could use to verify the adequacy of all critical safety functions and restore and maintain those functions when degraded.
D. Verify To prove to be true, exact, or accurate by observation such that the observed condition is in compliance with a procedural requirement. If the observed conditions are not in compliance with procedural requirements, action should be taken to change conditions to a state of procedural compliance.
,~s r _-
WP84989 SECTION V PAGE 1 e
w-w, -
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~s E. Caution
\'~'\
A means of drawing attention to situations or actions that can result in injury or damage to personnel or equipment. Cautions are surrounded by a border of " bullets."
F. Notes Descriptive or explanatory information that is intended to aid the operator in performing the associated instructional step.
Notes are surrounded by a solid border.
G. Conditional Statements
, Underlined words which emphasize the presence of several conditions or combinations of conditions that are required to accomplish a procedural step. Examples of conditional statements ares (IF, AND, OR, NOT).
"T. H. "GO TO" Statements (O
Statements which instruct the operator to proceed to a tab or steps based upon key plant parameters and indications. "GO T0" statements are surrounded by asterisks.
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!~ . WP84989 SECTION V l
PAGE 2 e
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2.0 INTEGRATION OF SAFETY FUNCTION CONCEPT INTO ANO-2 EMERGENCY OPERATING PROCEDURES A safety function is defined as a condition (s), the attainment of which is needed to either prevent core damage or minimize radiation releases to the general public. These conditions may be achieved by automatic or manual actuation of systems, from passive system perform-ance, or from natural feedback inherent in the plant design. Taken together the safety functions address a set of conditions which must-be achieved to ensure public safety.
There have been defined seven safety functions needed to mitigate events and contain radioactivity. These seven safety functions can be grouped into three classes.
A.- Anti-Core Melt Safety Function
- 1) Reactivity control
- 2) RCS inventory control
- 3) RCS pressure control
- 4) Core heat removal
- 5) RCS heat removal-B. Containment Integrity Safety Function C. Maintenance of Vital Auxiliary Power The anti-core melt class contains five safety functions: reactivity control, RCS inventory control, RCS pressure control, core heat
~4 removal, and RCS heat removal.
O r - k_
WP84989 SECTION V PAGE 3 O
g, - The purpose of the reactivity control safety function is to shut the
'(/
reactor down and keep it shut down, thereby reducing the amount of-heat generated in the core.
The purpose of RCS pressure and inventory control safety functions is to keep the core covered with an effective coolant medium. RCS pressure and inventory control are interdependent in a PWR design.
That is, actions taken to effect inventory control will affect pressure control and vice versa.
The purpose of the core heat removal safety function is to remove 'the decay heat generated in'the core and transfer it to a point where it can be removed from the RCS.
.s.
The final anti-core melt safety function is RCS heat removal. The purpose of this safety function is to transfer heat from the RCS to another heat sink.
The anti-core melt class of functions are the. primary safety functions to which the other classes are either backups or auxiliaries. To accomplish this class of functions, . the operator must ensure the continuous removal of decay heat from the core to the heat sink. By.
' concentrating efforts on maintaining proper heat transfer he can protect the core ar.d minimize radioactive release.
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WP84989 SECTION V PAGE 4 e
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The second safety. function' class is containment integrity. The
- Q,_ =-
primary objective of this safety function is to prevent a major-radioactive release by maintaining the integrity of the containment structure. The integrity of1the containment structure is provided by ensuring containment isolation (if necessary), and by ensuring containment temperature and pressure is maintained within designed limits. The containment temperature and pressure control is necessary to prevent overstressing the containment structure and to prevent damage to other equipment in the containment resulting from a hostile environment.
The third safety function class is maintenance of vital auxiliary .
power. Vital auxiliary power must be maintained in order to
.rs successfully accomplish the other six safety functions. Systems used
~
~
to maintain the six safety functions addressed above require proper
' electrical alignments for valve, pump and instrumentation operation.
By incorporating these seven basic safety functions into ANO-2 #
emergency procedures,-the operator is first supplied with expected parameters necessary to satisfy safety functions in an uncomplicated reactor trip. This will also' provide diagnostic aids that safety functions are not being satisfied 'and direct him toward " tabs" which focus on specific recovery actions.- These' recovery actions are designed' to provide alternate methods to maintain safety functions in situations other than uncomplicated reactor trips. This ;
I JWP84989 SECTION V PAGE 5 1
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format is designed to provide core cooling first and event identifica-tion second.
~
This combination of immediate actions and recovery guidelines (" tabs")~
provides a continuous check-of the safety functions and does not rely on immediate operator diagnosis. By satisfying the seven safety functions at all times, the operator accomplishes his primary goal of I
Proper heat transfer from the core, no matter what the specific event may be.
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i WP84989 SECTION V PAGE 6
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73 3.0 Format of ANO-2 EOPs d The ANO-2 E0Ps use the philosophy of a single combined EOP and a two-column, layered information format. ANO-2 uses this philosophy to provide those procedures necessary'to implement the safety function concept in all emergency. situations and place them in a single procedure using the " tab" reference concept. The combined EOP approach has been shown to provide a non-confusing method of operator guidance during simulated emergency operating conditions. The existing emergency procedures not covered by the combined EOP will be reclassified as abnormal operating procedures.
The two-column, layered information format has, through independent studies, shown to be the most effective form of information A conveyance to all operators regardless of information recall ability b
or experience.
The left hand column states briefly the objective to be accomplished.
This credits a trained operstor with knowledge of the "how to" and provides easily and rapidly identifiable general direction in managing a plant transient. This column contains a minimum of component nunbers and setpoints, no lists and no explanation. The objective stated in the left hat.d column relates to all actions called for in the right hand column.
n.
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WP84989 SECTION V PA3E 7 da
v.
The right hand column expands on the objective stated in the left Q.5 hand column.' This column may contain component numbers, setpoints, lists and explanations as well as detailed instructions. The right hand column can state how to accomplish the corresponding. objective stated in-the left hand column.
For example l if the left hand column says to verify proper operation of a system, the right hand column may list the parameters that
, indicate such proper operation, or if the left hand column says to isolate a system, the right hand column may list the valves that must be closed to accomplish'that isolation. This provides readily
, accessible information for the inexperienced operator or the
-operator who has temporarily forgotten a detail without cluttering up the left hand column with information not needed by most operators.
Cautions and notes extend across both columns and are included at appropriate locations ~ in the EOPs to provide information oriented towards alerting the operator to conditions that might lead to health' hazards or equipment or plant damage.
"Go.To" statements also extend across both columns and are placed at strategic locations to direct operators to " tabs" within the EOP recovery guidelines.
O WP84989 SECTION V PAGE 8 e
4.0 Content of EOP e , ,T
'~
A. Procedure Entry Conditions This consists of a list of entry conditions that requires the execution of the steps.in this procedure. It provides the operator with a means for confirming that he has chosen the
. appropriate procedure for the given emergency conditions.
B. Immediate Actions This section of the EOP is entered upon encountering any off-normal event which actuates or requires a reactor trip.
The post-trip immediate actions are designed to be independent of what has occurred. This constitutes a check of the significant safety functions and provides initial operator verifications in regard to the conditions of those safety functions.
The safety function status checks accomplish the following:
- 1) Safety function status is checked against desired plant parameter response to provide the operator with a complete status in regard co plant safety. The plant parameter indications are chosen to be easily determined from the control boards and require no special deciphering by the operator.
- 2) Safety function status checks provide the operator with information used to determine what actions, if any, are required to place the plant in a safe condition.
v WP84989 SECTION V PAGE 9 6
- 3) The safety function status checks discriminate between an O.
uncomplicated reactor trip and.other events. If there are other failures.which require attention, the criteria in
+
the-status check will not be satisfied, alerting the operator that more than a simple reactor trip has occurred.
Post-trip immediate actions are in a chart format for ease of presentation and understanding. In a chart format the relationship of safety function criteria to verification step is readily apparent.
The safety function assessment and accompanying verification step are prioritized according to two factors. The first factor is the importance to safety in terms of the consequences of not fulfilling that function and in terms of the time constant associated with that function. The second' factor in prioritizing relates to the natural order of steps in the control room.
C. Recovery Guidelines Ten recovery guidelines (" tabs") have been developed. These
" tabs" deal'with events which indicate a deviation of the plant from the normal control and/or heat transfer modes and provide corrective actions necessary to mitigate the problem. These ten tabs are:
, 1. Reactor Trip Recovery Actions
- . WP84989 SECTION V PAGE 10 4
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Emergency Reactivity Control Recovery Actions 1'~ '
- 3. Degraded Power Recovery Actions
- 4. Blackout-Recovery Actions
- 5. Overcool'ing Recovery Actions
- 6. Main Steam Isolation Recovery Actions t.-
- 7. Safety Injection Actuation Recovery Actions
- 8. S/G Tube Rupture Within Charging Pump Capacity Recovery Actions-
- 9. S/G Tube Rupture Greater Than Charging Pump Capacity Recovery Actions
- 10. Inadequate Core Cooling Recovery Actions 4
.()
v WP84989 SECTION V PAGE 11 e
L..
,_s 5.0 Principles of E0P Use (j
' Designed use of the ANO-2 EOP has been based on good operating practices, human factors considerations, and ANO-2 operations inputs. Its intended purpose is to convey the vital technical information in a straightforward manner minimizing possibly confusing instructions. Correct usage of the ANO-2 E0P will accomplish the intended purpose of satisfying the necessary plant safety functions incorporated into the E0P while also providing sound information for the operators decision-making process. When using the recovery guideline (" tab") approach, critical safety functions will be satisfied and necessary technical information dispensed regardless of the event experienced by the plant.
Figure 5.1 demonstrates the intended process for operator implementa-tion of the ANO-2 EOP.
4 e
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~ \d WP84989 SECTION V PAGE 12 6
r i
- g. FIGURE 5.1
- (_)
ANO-2 E0P USAGE FLOW CHART'
-l l l PROCEDURE ENTRY CONDITIONS l
[ l I
i l I l IS SGTR 2NDICATED? l YES l l l l l l NO l l l l l l
- l. .IMMEDIATE ACTIONS [ l l VERIFY SAFETY FUNCTIONS l l F I l l l l<_________________________________l___________________l l l 1
-l l l l l -ENTER REACTOR. TRIP l l l l RECOVERY TAB l l l
[ l l I I l I l l l l l PLANT CONDITIONS l YES l PROCEED TO l l l DICTATE ENTRY INTO l l RECOVERY TAB l l l RECOVERY TAB l l l l l (GO TO STATEMENT) l. l l l' l 1 l l l l l I NO l INSTRUCTIONS l l P l- PROPER FOR l NO l-l l l PLANT CONDITIONS l I COMPLETE REACTOR l' l l l TRIP RECOVERY TAB .l l l l l YES l l 1 l- I
- l. l l COMPLETE l
[ PLACE PLANT IN DESIRED [ l INSTRUCTIONS l l STABLE CONDITION l l l l' l
.O WP84989 SECTION V PAGE 13 b' '
,,- - ' A description of the intended process for operator implementation of -
- ( 'l the ANO-2 E0P is as follows:
A. Upon receiving a reactor trip signal or conditions requiring a reactor trip, as described in the EOP entry conditions, the operator would perform the immediate action steps (i.e.,
l' verification of safety function parameters). These immediate [
actions verify expected plant parameter response for an uncomplicated reactor trip and provide initial diagnostic aids.
B. One entry condition exists that does not begin with a reactor trip. If an SGTR is indicated, as described in the EOP entry conditions, the operator would go directly to the Recovery Guideline (" tab") for SGTR within charging pump capacity.
C. Upon completion of Immediate Actions, the operator would ~ -
- (N proceed directly to the Reactor Trip Recovery " tab." The d
reactor trip recovery tab provides primary objective step's in the left hand column and descriptive action statements in the I t
.right hand column to ensure the objectives are. satisfied.
I
-The objectives and~ action statements are prioritized in the same manner as'the safety function status checks performed in j the immediate actions section.
If the event is an uncomplicated reactor. trip, the reactor trip recovery tab leads the operator through the safety function-status checks and post-trip recovery actions.
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- WP84989 SECTION V' PAGE 14 i
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If the event'is not an uncomplicated reactor trip as provided 2 .- ,
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for in:the= Reactor Trip Recovery Tab,-then "Go To" statements-
' direct operators t6 one or, more of the remaining nine Recovery .
Guidelines " tabs."' These tabs direct _ response to the abnormal
- 9 condition-that sent.you to that-tab and then either continues-
'l
- with confirmation of critical safety-functions or returns you to l Reactor Trip tab.-
u.
ch'ecks are provided upon entry into any tab.to ensure that the correct tab.is selected-and that the critical safety functions j
.are being maintained. Direction to appropriate tabs is provided in the event that conditions warrant it.
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- WP84989
.. SECTION V PAGE 15
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t VI. BASES FOR ENTRY CONDITIONS AND IMMEDIATE ACTIONS 1.0 ENTRY CONDITIONS This section provides a list of conditions which require the use of the Emergency Operating Procedure (EOP). Entry conditions generally consist of any off normal event which automatically trips or requires a manual reactor trip to properly mitigate the consequences of the event.
A s'pecial case for entry into the EOP is a Steam Generator Tube Rupture (SGTR) greater than the Technical Specification (3.4.6.2) limit of .5 gpm on either steam generator. The SGTR is a unique emergency, and a different course of action should be used to
. minimize the release of radioactivity to the environment.- Since a
('T.
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reactor trip may or may not be required by a SGTR, if a SGTR is identified and a reactor trip has not occurred, the operator is directed to the " Steam Generator Tube Rupture within Charging Pump Capacity" Recovery Tab. This recovery tab contains actions and information necessary to. mitigate a SGTR event that has not, caused a reactor trip. If necessary, directions are also provided in'this tab to go to "SGTR Greater than Charging Pump Capacity" tab. -
.The SGTR may have been large enough to cause-a reactor trip. In this case, the operator will perform the immediate actions section and upon entry'into'the'" Reactor Trip Recovery" tab will be bnmediately directed' to the "SGTR Greater than Charging-Pump Capacity" tab. This recovery tab contains-actions and information necessary to mitigate a SGTR event
() that is greater than charging pump capacity. .
MD64989 SECTION VI - 1.0 PAGE 1
.a-
I
. 2.0 IMMEDIATE ACTIONS
\ J.
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'The emergency operating procedure (EOP) contains as its first operator actions a check of seven safety functions against acceptance criteria. The acceptance criteria consists of a listing of expected plant parameters and conditions that would exist shortly after a reactor trip with no further complications. There are two exceptions to the listing of expected plant parameters in the immediate actions. The first exception is under the reactivity control safety function when you manually trip the reactor. This step satisfies NUREG 1000 which states that operators should be
. trained to back up all automatic trips with a manual trip. The other exception' exists under the RCS pressure control safety function where the securing of two RCPs (one in each loop) is directed based solely upon a RCS pressure of s 1400 psia. This action ensures that the plant is maintained in a safe condition regardless of the initiating event, until further analysis is performed in the recovery guidelines to ascertain the exact nature of the event. This action initiates the trip two/ leave two RCP trip-strategy during transients as per CEN-268.
Verify, in this procedure, means to. ensure _ that parameters and systems are reacting as expected or take actions, as required, to restore _any safety functions that are in jeopardy. The safety.
function check in the immediate action _section of the EOPs provides the operator with the following:
.WP84989 SECTION VI - 2.0 PAGE 2 e .
1 l
A.
The safety ' function checks discriminate between an uncomplicated reactor trip and other events. The paramsters monitored are
~
consistent with conditions which would prevail only in the short-term after an uncomplicated reactor trip.
B. Check of safety functions and associated parameters give the 4
operator a complete status of plant conditions with regard to the seven critical safety functions relating to plant safety.
This provides objective decision criteria as to whether action is required in the short term to restore plant safety.
The Lumediate actions are in chart format for ease of presentation and understanding. In a chart format the relationship of safety function to associated parameters is immediately apparent.
.s
/
The safety function immediate actions are prioritized according to two factors. The first factor is the importance to safety in terms of the consequences of not fulfilling that function and in terms of .
the time constant associated with that function. The second factor 11 in prioritizing relates to the natural order of steps in the control room.
'\-
-D WP84989 i SECTION VI - 2.0 PAGE 3
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-q The following is a listing of the safety functions with an g-explanation of verification steps performed in the immediate actions.
- 1. Reactivity Control: >
This safety function is verified first since shutting down the reactor is foremost in importance to safety and reactivity responds with a very short time constant. It is essential to ensure the reactor is shut down, thus reducing the RCS heat input and mitigating the effects of any other events that may be sinultaneously occurring.
(a) Manually TRIP the reactor:
This step follows the philosophy that operators should be
-('s trained to back up all automatic reactor trips with a manual
.Q reactor trip as emphasized in NUREG-1000, Volume 1, " Generic Implications of ATWS Events at the Salem Nuclear Power Plant." Operators will initiate a backup reactor trip signal by. pressing both buttons for reactor trip on 2C-03 or both buttons on 2C-14.
(b) Verify all CEAs fully INSERTED:
Verifying all CEAs are inserted ensures adequte shutdown margin (SDM) (Technical Specification 3.1.1.1) to ensure that the reactivity transients associated with postulated accident conditions are within acceptable limits.
Calculations (per Procedure 2103.05, " Reactivity Balance Calculation"), ensure adequate SDM with one CEA stuck in
/% the withdrawn position. Therefore, if two or more CEAs are
- t/
MP84989 SECTION VI - 2.0 PAGE 4
- .-c not inserted after'a reactor trip, the reactivity control
'(s_-)
safety function is not to be considered-satisfied, since a SDM of 5% Ak/k cannot be inmediately assured.
(c) Verify reactor power DECREASING:
. Verification of reactor power decreasing by available instrumentation ensures nuclear characteristics response is as expected. A decrease in reactor power and a negative startup rate should be observed.' This rapid decrease in power is followed by a steady decrease in indicated power (approximately -1/3 decades per mintue) until the sub-critical multiplication level is reached.
fx h
WP84989 , SECTION VI - 2.0 PAGE 5 6 &
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- 2. Electrical Power:
[.s's This safety function is verified second in the immediate action sequence because of its potential effects on succeeding safety functions. Following a reactor trip, a turbine / generator trip quickly results in automatic rearrangement of the electrical distribution system. Improper electrical alignments may affect instrumentation or control features thus affecting correct diagnostics and methods of response to maintain succeeding safety functions.
(a) Verify Turbine-Generator TRIPPED:
Turbine / generator trip is verified because this is the initiating action for electrical alignment shifts. An improper turbine / generator trip may affect electrical
(~~ alignments thus affecting succeeding safety functions and could be the source of an overcooling event.
(b) All electrical buses ENERGIZED'from available startup transformer:
Proper electrical system transfers will maintain all electrical buses energized. Due to the different loads supplied by-each bus and the various problems encountered by the loss of individual components under various plant conditions, no attempt has been made to discuss the loss i
of individual buses.
p-t WP84989 SECTION VI - 2.0 PAGE 6 e ,
I' t._ - Startup transformer #2 feeder breakers to the Unit 2 buses s.t \
'N' are maintained in the " pall-to-lock" position and hold-carded. SU #2 is still considered'an available transformer and if loads do not automatically shift to SU #3,: consideration should be given to manually transferring buses to SU #2 providing the Unit 1
-electrical' lineup will permit it.
- 3. RCS Pressure Control:
This safety function ensures the RCS is maintained as a subcooled liquid, since a liquid has a higher heat transfer coefficient than a vapor and can therefore transfer more heat from'the core to the S/Gs. Analysis of previous reactor trip transient reports indicates that pressurizer pressure, in an
- (~' ancomplicated reactor trip, should remain in a band of 21800
(
psia but s 2300 psia.
Also included under this safety function, due to the potential short time period involved, is the securing of two RCPs (one in each loop) if RCS pressure should decrease to s 1400. psia.
Although-this parameter decrease indicates a reactor trip with complications, this action ensures that the plant is maintained in a safe condition regardless of the initiating event, until further analysis in the Recovery Guidelines is performed to
- ascertain the exact nature of the event.
i f ~
.WP84989 ,
SECTION VI - 2.0 PAGE 7 O
e 7- (a) Pressurizer pressure control system CONTROLLING pressurizer
, V pressure 2 1800 psia but s 2300 psia:
Reactor trip transient reports indicate that when the reactor trips prior to a turbine generator trip a pressurizer pressure in the mid-1800 psia range is expected. 1800 psia was chosen as'the low range to provide a margin below the expected ranges and above the SIAS setpoint (1766 psia) to allow for operator action to prevent SIAS actuation if possible.
The pressurizer pressure high range of 2300 psia was selected due to the pressurizer spray valve (s) automatic operation setpoints. Pressurizer spray valve (s) receive a 40% open demand signal at 2275 psia and receives a 100% open demand signal at 2290 psia. Therefore, a pressurizer pressure of 2300 psia would not be expected under normal ~ system operation.
-(b)1 IF RCS pressure is s 1400 psia, secure two RCPs (one in each. loop):
-Various transients may cause an immediate decrease of RCS pressure to s 1400 psia. Whenever RCS pressure is s 1400 psia, the securing of two RCPs (one in each loop) is desirable until further analysis of the event is performed, l' %
.G .
-WP84989 SECTION VI - 2.0 PAGE 8 e
s ai.
This action ensures that the plant is maintained in a safe LJJ.
condition, regardless of the initiating event, while
. minimizing RCS inventory loss if the event is a small break LOCA.
4 One RCP in'each loop is maintained to ensure the operator has pressurizer spray valve -control for cooling down and depressurization, provides continuous mixing of fluid in s reactor vessel head region minimizing possible void formation, and provides better mixing in the reactor vessel downcomer/ lower plenum region minimizing PTS Concerns.
r The setpoint of s 1400 psia allows . for plant specific s".J numbers where RCS pressure may stabilize corresponding to saturation pressure of the S/Gs and includes all expected instrument errors.
y;.
w x
s n
, s v' i
s p '
s V
WP84989 SECTION VI - 2.0 PAGE 9 ns ,
'O -
-.. f, . . - . =. - - - - - - . - - - - - - - - - - - - - - -- - - - - - - ~ ' - - - - -
- <x-) 4. RCS Inventory Control
LJ-RCS inventory control dir3ctly supports the RCS pressure control safety function, and together, they ensure that the RCS is maintained in a preferred _ state to transfer heat from the core to the S/Gs. Inventory control is required to ensure an adequate amount of fluid is available to provide a medium for decay heat removal.
(a) Pressurizer Level Control System CONTROLLING Pressurizer Level 2 29% but s 82%:
The pressurizer level control system (PLCS) should automatically respond by starting backup charging pumps and reducing letdown to minimum flow to assist in regaining
[~} the pressurizer level to the normal hot _ standby setpoint.
x_-
The lower limit for pressurizer level (2 29%) is based on the pressurizer low level heater' cutout setpoint. On an uncomplicated reactor trip,~the pressurizer will retain.
some indicated level, even though the heaters may be de-energized briefly on a low pressurizer level. If pressurizer level does decrease to < 29%, operator actions will be required to restore pressurizer heater operability when level is increased to > 29%.
. '\_/
/~] .
WP84989 SECTION VI - 2.0 PAGE 10 4
G
-s The upper limit for pressurizer level (s 82%) is provided
\
~~)~
to meet the requirements of Technical Specification 3.4.4.
The bases for this requirement is to ensure that a steam bubble is maintained in the pressurizer to accommodate pressure surges during operation.
(b) MONITOR VCT level and pressure:
After a reactor trip the additional suction from and reduced input to the VCT will cause its level to decrease.
Adequate charging pump suction pressure must be maintained by either blending to the VCT, ensuring the boron concentration of the makeup is 2 RCS boron concentration,
",d g . or by verifying charging pump suction is shifted to the
\. ,h RWT.
(c) NO S/G sample cooler (s) OR condenser off gas radiation monitors in alarm:
This step provides indication of a potential loss of RCS inventory via a SGTR. These indications provide additional diagnostic information to the operator.
WP84989- SECTION VI - 2.0 PAGE 11 O
+
' (d)
NO' cams OR containment area monitors in ALARM:
This step provides indication of a potential loss of RCS inventory via a LOCA. These indications provide additional diagnostic information to the operator.
(e) Containment' sump level NOT INCREASING:
This step provides indication of a possible SLB or a potential loss of RCS inventory via a LOCA. This indication provides diagnostic information to the operator.
1 r
A t
S U
WP84989 SECTION VI'- 2.0 PAGE 12
<r 4
5 e
_.mA mn s-s-s--e o e n on-verrer*~ -re wrow wr-_ .
. g-g ' 5. RCS Heat Removal V. - :
This safety function addresses the ability to remove heat from the RCS to improve its core heat removal capability. In an
. uncomplicated reactor trip, the preferred heat sink is at least one operable S/G.
.(a) Tave 2 540*F but s 555*F:
Tave in this band assures the operator of adequate RCS heat removal via the S/Gs. The upper limit of 555* is chosen due to its saturation pressure being less than the lowest S/G safety setpoint (1078 psig). The lower limit
.(~ ofl540*F is based on values normally seen after an
- v-uncomplicated reactor trip. A temperature less than 540*F indicates overcooling which can be caused by overfeeding, oversteaming, etc.
(b) SDBCS CONTROLLING S/G pressure 2 950 psia but s 1090 psia
-a Based on past operating experience, S/G pressure is expected to be within this band following.an uncomplicated
, reactor trip. .The lower limit of 950 psia was selected because it corresponds to the Tave limit of 2 540*F. A low S/G pressure could be an indication of possible RCS overcooling. The upper limit of 1090 psia was selected to
(~N -~ avoid challenging.the S/G safety valves. If these limits
- t)
WP84989 SECTION VI '2.0 PAGE 13 W-a
s x ,
--g
- - for.S/G pressure are not being maintained, this may be an
's_/
indication that the SDBCS is not functioning properly or .
that a SLB has occurred.
~
' (c) S/G level 2~10% but s'90% with MFW OR EFW systems RESTORING level:
With S/G' level in the' described band, the operator is assured of an available heat sink. The lower limit of 10%
(narrow range) ensures that enough of the tube bundle is covered to provide adequate heat transfer from the RCS to'the secondary. The upper limit of 90% (narrow range)
< establishes the upper control boundary. S/G level rising
{ above this upper limit signals the operator to a feedwater control proble'm which, if left unchecked, -could result in -
S/G overfill.
4 9
4 k'
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WP84989. SE,CTION VI - 2.0 PAGE 14 e e ,
- y
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6.. - Core Heat Removal
((
I This safety function addresses the ability to circulate cooling s
fluid,'of the proper state, through the core to remove decay heat. Core-heat removal is the. ultimate goal of'the EOPs. !
[y (a)- All RCPs RUNNING A
Following an uncomplicated reactor trip, all RCPs should t
be running providing forced flow for removal of core decay heat. Flow through the core is the ultimate goal of the s-core heat removal safety function whether it is via all n RCPs, some combination of RCPs, natural circulation or
-5
..jf~s safety injection flow through the core and out the break.
- d .
(b) RCS margin'to saturation 2 30'F:
j- -
Adequate margin to saturation ensures that the condition. '
of the fluid around the core is maintained in the j
preferred state providing single phase cooling. The limit of 2 30*F was chosen due to the possible inaccuracies and uncertainties of the margin to saturation calculators and their inputs.- If 2 30'F margin to saturation is indicated, allowing for the errors of the calculators and their inputs, the RCS should not be at saturated
. conditions.
, ' '%m i
WP84989 SECTION VI - 2.0 PAGE 15 r i a
A *
-. , . , , . - - - _ .._..._.-,_,,,,---.__-_--..-,--.,-,,-,mm.-_.-,.-_.,...-,-,_...._..,,,,c,_..,,,_
s 7. Containment Integrity:
,5 )j This safety function.is designed to ensure containment building parameters are maintained within allowable limits. Containment pressure and temperature are verified to provide additional diagnostic information to the operator. They are not expected to change noticeably following an uncomplicated reactor trip.
An increase in containment building pressure and/or temperature could be an indication of a LOCA or SLB inside containment.
(a) Average Containment Building pressure 213 psia but s 16 psia:
'. This range of containment building pressure was selected based on past operating experience. The upper band limit of s 16 psia is also based on the limits imposed by Technical Specification 3.6.1.4.
(b) Containment temperature s 140'F:
This limit on containment temperature was selected based on past operating experience and on the limit imposed by Technical Specification 3.6.1.4.
m WP84989 SECTION VI - 2.0 PAGE 16 e
s VII. BASES FOR RECOVERY GUIDELINE TABS 1.0 REACTOR TRIP RECOVERY 1.1 Operational Goals The operational goals of the reactor trip recovery tab is to lead the operator through reverification of safety functions and post-trip recovery actions.
If safety function status cannot be maintained as indicated in the Reactor Trip Tab, then "Go To" statements direct operators to one or more of the remaining nine Recovery Guideline
" tabs." These tabs direct response to the abn'drmal condition that sent you to that tab and then either continues with confirmation of critical safety functions or returns you to the r~'s . Reactor Trip Tab.
' L] '
'l.2 Description of Reactor Trip A reactor trip is a shutdown of the reactor accomplished by the rapid insertion of the control element ssemblies (CEAs) into
,i the reactor core causing a rapid re. tion in the primary heat source to approximately 6%. It is automatically initiated by the reactor protective system (RPS) when monitored plant parameters exceed predetermined setpoints. A reactor trip can also be initiated manually by the operator if plant conditions warrant.
Automatic reactor trips may also occur should RPS components fail such that a reactor trip signal is generated.
.r~)
b WP84989- SECTION VII - 1.0 PAGE 1 e
-f s. A reactor trip may occur as a result of. automatic action initiated
\--) ,
by the RPS in response to any of the following parameters:
Parameter. Setpoint
- 1. Linear Power Level-High 110% of ra*.ed thermal power
- 2. Logarithmic Power-High .75% of rated thermal power
- 3. ' Pressurizer Pressure-High 2362 psia
- 4. Prassurizer Pressure-Low 1766 psia
- 5. Containment Pressure-High 18.4 psia
- 6. Steam Generator Pressure-Low 751 psia 7 Steam Generator Level-Low 46.7%
- 8. Local Power Density High 20.3 kw/ft
- 9. DNBR-Low 1.24
- 10. Steam Generator Level-High 93.7%
A turbine trip signal is generated by a reactor trip to prevent overcooling the RCS by drawing excess steem from the S/G without the primary heat source present.
While a reactor trip signal is not generated by a turbine trip, the subsequent transient placed on the RCS may cause a reactor trip setpoint to be reached.
-m s_,
WP84989 SECTION VII - 1.0 PAGE 2 e
m___ _
I i
~ ,
- ;-~ 1.3 Safety Functions Affected
-t t-
'~'
A reactor trip is an automatic feature designed to place.the reactor in a suberitical condition, thereby achieving the recctivity control safety function. .This does not affect the acceptable status of any other safety function if support systems operate as required to place the plant in a stable-condition. All safety functions should be monitored to assure 5
public safety and detect conditions which may lead to unacceptable e safety function status.
. 1.4 Major Parameter Response A. Reactor Power As a result of the reactor trip initiation,'the CEAs will
~
be rapidly inserte'd. Steam flow to the turbine generator-
) will be terminated, the turbine generator output breakers
%_ J will open and the MFW flow will automatically ramp down to 5% flow demand. A rapid decrease in reactor power and a negative startup rate will be observed. This rapid decrease in power is followed by a decrease in indicated power (approximately.-1/3 decades per minute) until the subcritical multiplication level is reached.
L t e 4
A
'uj l
-WP84989 SECTION VII - 1.0 PAGE 3 e
w_
,- B. RCS Temperature A./
Initially, feedwater temperature decreases sharply due to termination of turbine extraction steam heating to the feedwater heaters and/or due to actuation of EFW. Heat from the RCS is absorbed by the cooler feedwater supplied to the S/Gs. At power, there is a large differential between RCS T,y, and average S/G temperature. Following the trip of the reactor and the turbine, the heat transfer rate from the RCS to the S/G decreases and the RCS to S/G AT decreases to a few degrees. As a new equilibrium is achieved, the combined effect of the cooler feedwater and the S/G heating up to an average temperature closer to RCS temperature results in a net heat extraction from the RCS.
, () -Loop differentials between hot and cold leg temperatures s-will drop to less than ten degrees and RCS average tempera-ture will decrease to the hot zero power temperature _which is controlled by the Steam Dump and Bypass Control System (SDBCS).
C. Pressurizer Pressure and Level Pressurizer pressure and level will initially decrease due to the lowering of RCS temperature and subsequent RCS density increase. However, this effect will usually be tempered by operation of pressurizer heaters and charging pumps to restore pressure and level to the hot zero power band. There is a potential for pressurizer level to decrease to heater cutout level (29%) and manual resetting
(~)
%) or heaters after regaining level > 29% is required.
WP84989 SECTION VII - 1.0 PAGE 4
-e
[~ ~ ]
. 7 s' - D. Steam Generator Pressure !
^ L.,)
Since a reactor trip causes a turbine trip, the reduced steam demand causes a rapid rise in S/G temperature and pressure. The SDBCS automatically responds to control main steam pressure at the hot standby setpoint.
E. Steam Generator Level After a reactor trip, S/G level decreases rapidly. S/G level is measured in the downcomer region. In the tube bundle area there exists a mixture of water and steam bubbles relative to the amount of heat transferred to the
, secondary. When steam flow from the S/G is stopped by the turbine trip, S/G saturation pressure and temperature increase-rapidly. This increase in S/G pressure causes the ~!
r steam bubbles in the tube bundle area to be. compressed and
-[ )
allows the water in the downcomer area to flow into the tube bundle area. This phenomena (shrink) results in a r
j lower indicated water level. :
After a reactor trip, the selected MFW pump will be tripped by the main turbine generator circuitry if both pumps were
- 'nning prior to the trip.
h
- (-) t WP84989 SECTION VII - 1.0 PAGE 5 l
e
-s The Feedwater Control System (FWCS) reacts to a reactor trip
^
by generating a reactor trip override (RTO) signal. The RTO signal closes both MFW regulating valves, reduces the remaining MFW pump speed to minimum, and adjusts MFW bypass valves to maintain - 5% flow demand. If left in automatic, the FWCS will slowly return S/G levels to ~ 70%.
If S/G 1evels decrease to < 46.7%, the EFW system will be actuated and will be available to restore S/G level.
Operators should be cautioned not to overreact to the low S/G levels immediately following a reactor trip. Excessive feeding of the S/Gs with colder feedwater can result in RCS i /'~') temperatures being reduced below the desired no load value.
p This decrease in RCS temperature could cause excessive pressurizer level and pressure decrease, which could result in an SIAS.
t...~I WP84989 SECTIO!! VII - 1.0 PAGE 6 e
r 1.5 Bases for Reactor Trip Recovery Actions Symptoms of an S/G Tube Rupture (SGTR):
Addressing the symptoms of a SGTR immediately upon entering the recovery actions for reactor trip points out the uniqueness of this event. Because of the unusual and rapid operator actions required to mitigate a SGTR and prevent release of radionuclides to the environment, the operator is cautioned to review four symptoms associated with a SGTR. The four symptoms are based on increased radiation indications of steam generator effluents. The indications are chemistry sample activity,
. condenser off gas monitor, steam generator blowdown sample monitor (s), and main steam line radiation monitor (s). Should definitive indications exist of a SGTR, the operator proceeds
,- to the SGTR Greater Than Charging Pump Capacity tab.
SIEP 1: Verify the reactor is shut down:
This step addresses the safety function of reactivity control by ensuring that trip signals to selected sets of Reactor Trip Circuit Breakers (TCBs) have been received and verification that the reactor is shutdown. For all emergencies, ensuring the reactor is shutdown and maintaining it shutdosn, thereby reducing the amount of heat generated in the core, minimizes the consequences of the event.
WP84989 SECTIO!! VII - 1.0 PAGE 7 e
A. Verify appropriate sets of TCBs are open:
This addresses the proper operation of the breakers upon receipt of a RPS trip signal or manual trip signal and ensures that power to all CEAs is interrupted. An appropriate set of TCBs is defined as any combination that will de-energize both CEA power panels (2C70 and 2C71).
B. Verify all CEAs are fully inserted:
This step ensures adequate shutdown margin (SDM)
(Technical Specification 3.1.1.1) to ensure that
') the reactivity transients associated with postu-lated accident conditions are within acceptable limits. Calculations (per Procedure 2103.05,
" Reactivity Balance Calculations"), ensure adequate SDM with one CEA stuck at the withdrawn position. Therefore, if two or more CEAs are not inserted after a reactor trip, the reactivity control safety function is not to be considered satisfied, since a SDM of 5% cannot be immediately assured.
WP84989 SECTION VII - 1.0 PAGE 8 j
___j
,s GO TO STATEMENT
- Direction to the Emergency Reactivity Control Tab addresses a failure of
- the reactivity control safety function. Entry into this tab will provide
- guidance on options to de-energize TCBs (if necessary) and will direct the
- operator to commence emergency boration to establish adequate shutdown *
- margin.
- C. Verify reactor power decreasing:
Verification of reactor power decreasing by available instrumentation ensures nuclear characteristics response is as expected.
(v)
STEP 2 Verify proper response of the electrical system:
Verifying proper response of the electrical system-ensures that the vital auxiliary power safety function is maintained. Improper response of the electrical system could affect numerous succeeding safety functions. Electrical power must be present to have the instrumentation and controls necessary to satisfy the succeeding safety functions.
f) v WP84989 SECTION VII - l.0 PAGE 9 e
ih
. A. Verify the' turbine is tripped:
w./
This ensures that the major source of heat removal from the RCS has been removed. The turbine-trip also initiates electrical system transfers. Failure of the turbine to trip could challenge several safety functions, such as:
reactivity control, vital auxiliary power, RCS pressure control, and RCS inventory control. An uncontrolled RCS cooldown, due to the failure of the turbine to trip, could result in ESFAS actuations (i.e., SIAS, MSIS), and a potential for pressurized thermal shock (PTS) exists.
O
- 1) Verifying all turbine control valves OR all turbine stop valves are closed ensures that steam is secured to the HP turbine thus preventing overcooling of the RCS and possible overspeeding of the turbine.
- 2) Verifying all turbine intercept /stop valves are closed ensures proper turbine trip actuation and prevents a possible turbine overspeed condition.
WP84989 SECTION VII - 1.0 PAGE 10 e
73
' i, 1-
- 3) IF all-turbine valves did not close as
'"^
required AND an uncontrolled RCS cooldown is in progress, implying the source of the cooldown is the turbine, then options for closing the turbine valves or the MSIVs are listed.
a) The manual turbine trip push button on 2C01 is preferred for initiating turbine trip sequence.
b) If the severity of the cooldown, time
. and available personnel permit, then tripping the turbine at the front standard is next in preference.
- ("ig c) Placing EH pump handswitches in " pull L/
to lock" will'also cause a loss of the MFP which is supplying the S/Gs. Since the EFW system should also be supplying the S/Gs, this should not affect'S/G inventory control. This is listed only as an option and depends upon severity of the transient and operator preference as to whether to use this or step d) first.
d) Closure of MSIVs is another option and is preferable to a MSIS if the cooldown cannot be terminated using one of the v
~] above steps.
WP84989 SECTION'VII - 1.0 PAGE 11
- l. .
I l
1 B. Verify generator output breakers (5130 and
. 5134) AND exciter field breaker are open on panel 2C01:
This step ensures proper electrical isolation of the turbine generator and prevents motorizing the main generator.
C. Verify that all 6900V, 4160V and 480V buses are energ'ized from an operable startup' transformer:
This ensures that a proper electrical transfer has been made. Failure'o.f the electrical buses to properly transfer may mask indications of safety function status and may affect' methods of control. Two particular_ electrical problems are addressed: Degraded Power and Blackout. No
-attempt has been made to give guidance on loss of
~
individual buses,- except' for Step 1) below,-- since each occurrence will be unique due-to.the load--
variations on each bus.
- 1) 'IF a bus fails to transfer AND there are no-
. bus lockout alarms, one attempt to re-energize that bus should be considered if required loads are powered from that bus. If a bus WP84989 SECTION VII - 1.0 PAGE 12
7_q , lockout alarm is present, determination and t !
%.)
correction of the cause is required before re-energization of that be .
Symptoms of Degraded Power:
Degraded power is defined as a loss of off-site power supplying 6900V (H)'and 4160V (A) buses with one or more 4160 volt ESF bus (es) (2A3/2A4) being supplied by the emergency diesel generator (s). Recognition of degraded power is accomplished by L
'having the operator review these three symptoms indicative of
, degraded power. The uniqueness of this electrical system failure and the effects on safety function parameters and control should be recognized by the operator.
10 LJ GO TO STATEMENT *
- Direction to Degraded Power Tab addresses a specific type *
- of failure of the electrical power safety function. Under*
- these conditions, enough electrical power is available to *
- satisfy the required safety functions. Entry into this *
- tab will ensure that electrical power is maintained and *
- allow for monitoring and maintaining desired safety func *
'* tions and possible re-energization of desired electrical *
- buses. *
)
v WP84989 SECTION VII - 1.0 PAGE 13
c h:
j-v -- _ Symptoms of Station Blackout l ssb Station Blackout is defined as a loss of all AC power but with DC power still available. Recognition of Blackout con-ditions is accomplished by having the operator review these three symptoms indicative of Blackout. The uniqueness of this electrical system failure and the effects on safety function
- parameters and control should be recognized by the operator.
G) TO STATEMENT
- Direction to Blackout Tab addresses a failure of the vital *
- electrical power safety function. Entry into this tab
- e
- will provide information.for1 monitoring safety functions *
- under adverse conditions and supply direction to -*
L b \ms/
(\' -
.
- attempt to re-energize power supplies. *
- STEP 3: Verify pressurizer heaters and/or spray valves are responding to restore and maintain RCS pressure to setpoints:
4 Reactor coolant pressure control is required to keep the reactor coolant subcooled so that the coolant is in the preferred state to transfer heat from the core to the S/G's. This step addresses the RCS pressure control safety function and supplies in-formation to ensure that it is maintained at desired
() setpoint. Proper automatic operation of pressurizer -
WP84989- SECTION VII - 1.0 PAGE 14
p
,s.
heaters and. spray valve (s) is expected to maintain
~
this safety function under uncomplicated reactor trip conditions, but instructions for manual control of pressurizer heaters, spray valve (s) and use of auxiliary spray valve is provided, if necessary. Operation of the pressurizer pressure controller (s) (2PIC-4626A or 2PIC-4626B) to adjust pressure to a desired setpoint may be required.
Adjusting the controller to the desired setpoint
. allows the operator to maintain pressurizer pressure outside of the normal band if plant conditions require.
Pressurizer pressure is expected to be maintained above 1766 psia (SIAS setpoint) at all tir -s, if possible.
i /i
'N.-}
WP84989 SECTION VII - 1.0 PAGE 15 m
A) IF required, take manual control of pressurizer
'~'
heaters and/or spray valves, to restore and main-tain RCS pressure at setpoint:
This step has the operator assume manual control of the pressurizer spray valves and/or heaters in an attempt to regain control of RCS pressure should the automatic control systems fail.
- 1) IF spray valve leakage is suspected:
a) Select manual on affected spray valve handswitch and hold in close position Holding the handswitch in "close" drives the valve shut to its torque limit. When this limit is reached, the motor is deenergized, the torque relaxes allowing the circuit to reenergize thus pulsing the valve shut.
b) IF necessary, isolate the affected spray valve If repeated attempts to shut the spray valve are unsuccessful, the affected
'~N valve is isolated.
! V i
, WP84989 SECTION VII - 1.0 PAGE 16 I
9
r-s B) IF pressurizer level decreases to < 29%, all J>
pressurizer heaters in auto will be deenergized by interlock:
- 1) Verify all backup heaters in " Auto" or "0FF":
If a backup heater bank switch is in "0N",
the <,29% pressurizer level interlock will not deenergize that bank of heaters.
- 2) Restore pressurizer level to > 29%.
This step ensures that sufficient level to cover all heaters is regained prior to reenergization to prevent possible loss of heater integrity.
- 3) Place the pressurizer proportional heater ,
handswitches to "0N" to regain control of the proportional heaters:
- 4) Place the pressurizer backup heater hand-switches to "0FF" A!!D back to "AUT0" or "0N" to regain control of the backup heaters
)
WP84989 SECTIO!! VII - 1.0 PAGE 17 1
0 e
L y
. ,n These steps instruct-the operator in the proper method of regaining pressurizer heater control once adequate level is regained.
c) If pressure cannot be controlled with normal spray valves, manually operate pressurizer auxiliary spray valve to' limit RCS pressure to
<-2300 psia:
The use of the auxiliary spray valve may be required if the redundant normal spray valves are inoperable OR if a loss of all RCPs is experienced. Maintaining RCS pressure < 2300 psia ensures RCS safety valves are not challenged and maintains a standard upper limit for the RCS w
pressure safety function.
- 1) Verify at least one charging pump is opera-ting on 2C09 to supply auxiliary-spray flow.
- 2) Open 2CV-4824-2 (Auxiliary Spray Valve) on 2C09 to allow minimal flow, thus preheating auxiliary spray line.
'T 3) Close 2CV-4827-1 AND 2CV-4831-2 (loop charging valves) on 2C09 to provide full flow through auxiliary spray line.
I O
/ i
^ C/
WP84989 SECTION VII - 1.0 PAGE 18
^-
,________..__.._.-.______m._ _ _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ~ - - - ' ' - - - ' - - - - - ' ' - - ' - ' ~ '^ - - ' - ' " - ~ ' - - ~ ~ ~ - ' ' ~ ~
.]
s
-. 4) Verify closed 2CV-4651 AND 2CV-4652 (normal
(
pressurizer spray valves) on 2C04 to ensure full flow is directed through the auxiliary spray line:
When using the auxiliary spray valve, finer e m pressure control may be obtained by throt-
.___ tling-2CV-4651 or:2CV-4652 open and_ allowing i
auxiliary spray flow to be diverted back through the main spray line to the loop. This also will minimize the number of spray nozzle thermal. cycles by eliminating the need to open and close the auxiliary spray valve.
h 5) IF the pressurizer and charging water tem-perature difference.is > 200'F, complete L
Attachment "A" of OP 2103.05 for each spray-ing cycle:
If the difference between pressurizer and charging water temperature is > 200'F, as measured by pressurizer water phase tempera-ture (2TI-4622) and regenerative heat exchanger to RCS (2TI-4825), then logging of each spray cycle is required to ensure Technical specification (5.7.1) is maintained.
fm.
N.] _
.WP84989 SECTION VII - 1.0 PAGE 19 e
L . - -
., s , ,-
x <
- i t
f q :.a ' = STEP:4: Verify Proper RCS Inventory Control:
y,y -
.RCS inventory control directly supports the RCS e-pressure control safety function, and together, they
-U
. , ensure that the RCS is maintained in a preferred
+
state to transfer heat from the core to'the S/G's.
Inventory control is-intended to ensure an adequate 7,
- i. amount of fluid is available to provide a medium to remove decay heat. On an uncomplicated trip, the pressurizer will retain some indicated level even'
.though the pressurizer heaters may be deenergized briefly on low pressurizer level. Actions are-l- ,
selected to ensure proper automatic; operation of,the i normal inventory control system. Also, proper inventory control provides a means to monitor for
. loss of coolant accidents.
-v ,y A .- = Verify charging and/or letdown systems are
, responding to restore and maintain pressurizer 4
level at program levels The, automatic operation of the pressurizer ;
' 3'a' \ '
level control system (PLCS) is the preferred ,,
t method for inventory control. The PLCS is
.c ~
verified to be functioning to restore pressurizer p;
s_
WP84989?
o SECTION VII - 1.0' PAGE 20' >
, , e
^ [ _ ;[ _ *
-~
m
c ii-
- lt 1
7-4 level to program level (~ 41%). If not, PLCS V
. should be operated manually to restore and maintain pressurizer level above the pressurizer heater cutoff level (~ 29%).
s i-
- -- ,B. Verify adequate suction source (s) to charging pumps:
I l'
The source (s) of water for use in controlling RCS inventory depends on the total amount of fluid necessary for makeup to the RCS and the time frame over which the fluid must be intro-duced23 ' Adequate suction to the charging pumps
-I$$?
f yS ensures adequate fluid is available to restore Vy .,.
or maintain RCS inventory.
, ?
~.,
,. level alarm (~ 57%)..-is , expected and adequate
~
VCT-level is conside, red to be above the low
~
low leve1 alarm (~.9%). Blending with a
. solution'of"> present RCS boron concentration ensures the Technical Specification SDM of 5% is maintained. If a reactor restart is c
t,J .
WP84989 SECTION VII - 1.0- PAGE 21 e>
y w w
l 5 ;
1
,ia , expected to commence within 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />, con-I, t
,1 -
sideration should be given to Xenon conditions for determining the boron concentration of the makeup solution.
- 2) Verify RWT aligned to CVCS:
If the VCT level decreases to 5% or if adequate makeup cannot be maintained to the VCT, the RWT should be lined up'to the charging pump suction.
a) Verify open RWT to charging pump suction
S sj.
valve (2CV-4950-2) to ensure a continuous source of fluid is maintained at the charging pump suction.
b) Verify closed VCT outlet valve (2CV-4873-1) to prevent further decrease of VCT level.
C. Monitor the following parameters for loss of RCS inventory indications:
- 1) The S/G(s) sample cooler radiation monitor (s) increasing provides possible indication of primary to secondary leakage
?()
~
in the S/G.
- WP84989 SECTION VII - 1.0 PAGE 22 6,
/__ .
2). The condenser off-gas radiation monitor
% )y' increasing provides possible indication of primary to secondary leakage in the S/G.
- 3) The Containment Atmosphere Monitor (s)
(CAMS) increasing is a possible indication-of RCS leakage inside containment.
- 4) The containment area radiation monitor (s) increasing is a possible indication of RCS leakage inside containment.
- 5) The containment sump level increasing is a possible indication of RCS or secondary leakage inside containment. This indication is not addressed in the GO TO
(~N ctatements since it is not a specific L) -
. symptom of any of the accidents. It does provide indication of abnormal conditions inside containment.
GO TO STATEMENT
- This statement directs the operator to.the "0VERC00 LING" tab when indica-
- tions of .an excessive'stean. demand are present but no MSIS signal has been *
'
- generated. The resultant RCS cooldown will cause pressurizer pressure,
- pressurizer level, and S/G pressure to decrease. Entry into the "0VERCOOL
- ING" tab will provide guidance to the operator-for satisfying the safety *
. functions.and controlling the plant with a overcooling condition present. '*
'Q:
O WP84989 SECTION VII - 1.0 PAGE 23 Pm-T w -* - =-4&y'+w.,i s'-**e
j *******************************************************************************
GO TO STATEMENT *
- This statement directs the operator to the "MSIS" tab when indications of a *
- main steam leak exist. Pressurizer pressure and level will be decreasing *
- due to the reduction of RCS temperature. S/G pressure will be decreasing
- f
- *Ldue to the steam demand resulting in a cooldown of the RCS.
Entry into
- this tab will provide guidance to the operator for satisfying the safety
- functions and controlling the plant::withpa. MSIS -present. . - - - - -
- GO TO STATEMENT
- This statement directs the operator to the "S/G TUBE RUPTURE GREATER THAN
- CHARGING PUMP CAPACITY" tab when indications of.a S/G tube rupture exist.
- _ Pressurizer pressure and level will be decreasing due to the loss of RCS
- inventory into the S/G. S/G pressure should remain constant since RCS *
~*
temperature should not be changing. Secondary activity should be increasing
- due to the leakage of contaminated reactor coolant into the S/G. Entry into*
this tab will provide. guidance to the operator for satisfying the safety
- functions'and controlling the plant uith a S/G tube rupture present.
- e
-%.)
WP84989- SECTION VII - 1.0 PAGE 24 m
1 wy s,wy- ,---..- 4--- . .-e. - - - - - - - - - e.ey--s +e--- -- e. & w--1-w--- ecw.w- --e- ehw - - - - ,--- w w- w. ---r-----T
N~)
- GO TO STATEMENT *
- This statement directs the operator to the "SIAS" tab when indications of a *
- loss of coolant accident (LOCA) exist. Pressurizer pressure decreases *
- due to the loss of RCS inventory. Abnormal pressurizer level indications *
- will exist due to the loss of RCS inventory. If the leak is not in the *
- pressurizer, pressurizer level should decrease as expected. If the leak is *-
- in the pressurizer steam space or level indication piping, the pressurizer *
- level indications may increase or indicate differently. In any case, pres *
- surizer level should not remain constant during a LOCA. S/G pressure should*
- remain constant since RCS temperature should not be changing. Secondary
- activity should not increase since there is no primary to secondary leakage.*
- Entry into this tab will provide guidance to the operator for satisfying the*
-f3
- safety functions and controlling the plant with a SIAS present. *
.(-)
STEP 5: Verify RCS Heat Removal by verifying operation of the Steam Dump and Bypass Control System, Main Feedwater System, and Emergency Feedwater System:
The removal of heat from the RCS is necessary to maintain long-term core heat removal. This step verifies operation of the systems required to maintain a S/G as a RCS heat sink since the S/G(s) are the primary means of removing heat from the RCS.
f~
V)
'WP84989 SECTION VII - 1.0 PAGE 25 e
r 4
- A) Verify S/G pressure (s) AND Tave are being
~# '
maintained:
By verifying S/G pressure (s) and Tave, the
~
operator ensures that sufficient main steam is being removed from the S/G(s) to remove core
, 2 .- m-- ~~ decay heat from the RCS.
- 1) The no-load setpoint for the SDBCS should Ebe ~ 1000 psia. This setpoint may be biased up or down if pressurizer pressure is below or above 2250 psia. T,y, will vary slightly depending.upon the SDBCS setpoint. The no-load T value is
- km ,') "V" 545'F. The SDBCS setpoint is based on maintaining this value of T,y,.
a) If the main' condenser is available, the SDBCS bypass valves are the preferred method of maintaining S/G pressure. These valves are preferred because they do not result in a
. reduction of secondary inventory.
Also, one'of the SDBCS bypass valves (2CV-0303) has'a rating of 5%. This
,Y _
'l }
^ %>
, WP84989 'SECTION VII - 1.0 PAGE 26
- 6 a -
,4_y-, ,,.-y ,-- e ,mr---- -
~"g ~ * ~ ' ' ' '"""r* * * " ' '
,_ - valve provides more effective control
( )
^'
of S/G pressure. If condenser vacuum degrades to.the interlock setpoint, the'SDBCS bypass valves will no longer be available.
t b) When the main condenser is not available, the SDBCS atmospheric dump valves are used. Anytime _the use of
. these valves is required, the operator should verify the correct alignment of the valve controllerc and permissive switches.
-s
)'
- . 'GO TO STATEMENT
- This-statement directs the operator'to the "0VERCOOLING" tab if T,y, is
- l< 540*F and decreasing. This tab will provide directions to the operator
- x
~
- 2) If steam is-not removed from the S/G(s) via the SDBCS, S/G pressure may increase to the S/G safety setpoint. When the S/G safety valves are used to control S/G pressure, T, , should be ~ 555'F corresponding to a S/G pressurelof ~ 1100 psia.
.A-V WP84989 SECTION VII - 1.0 PAGE 27 m
v --- a ,y*w-* *:n r --
9 , + .&* + w-,-yc,y- +=e w - =-we ,-g*-
7-~ B) Verify S/G levels are being slowly restored to ~
(',) '
70%:
By verifying that the S/G levels are being restored, the operator ensures a source of feedwater is available to maintain the S/G(s) as the RCS heat sink. --
CAUTION STATEMENT .
. THIS STATEMENT REMINDS THE OPERATOR TO BE ALERT FOR CONDITIONS THAT .
- COULD RESULT IN S/G OVERFILL. SINCE THE MAIN FEEDWATER SYSTEM IS .
f
. ASSUMED TO BE THE SOURCE OF THE S/G OVERFILL, SECURING MAIN *
. FEEDWATER PUMPS AND CLOSING MAIN FEEDWATER BLOCK VALVES SHOULD .
. PLACE S/G LEVELS UNDER CONTROL.
- 1) This step directs the operator to verify proper alignment of the main feedwater (MFW) and condensate system. The MFW and con-densate systems should be automatically aligned to slowly restore and maintain S/G levels at ~ 70%.
~[)
- v .
-M?84989 SECTION VII - 1.0 PAGE 28-e 6
a) The MFW system is verified to be b.s') '
operating in " Reactor Trip Override" (RTO). The " Control Element Drive Mechanism control System" (CEDMCS) undervoltage relays signal the 3 "Feedwater Control Systems" (FWCS)-
to operate in RTO. Basically, RTO will position the MFW valves and adjust main feed pump (MFP) speed to establish - 5% feed flow to the S/Gs. This will continue until the level setpoint is achieved.
rx 1) One MFP is verified to be
-b operating at minimum automatic speed and the second MFP is verified tripped. The MFP that L
is verified tripped will be the pump selected with the preferred trip selector switch, 2HS-0352 l on 2C02. The selected pump will trip only if both MFPs are running.
f The trip of the selected pump is initiated by a main turbine trip.
t'
- t,_T
) '
WP84989 SECTION VII - 1.0 PAGE 29
- 1. -
.1
' '~'
- 2) Both main feedwater regulating valves (MFRV) (2CV-0748 and 2CV-0740) are verified closed on 2C02. The MFRV position indication and the HERV controller output should be verified to be indicating - O.
.and 2CV-0744) are verified to be positioned - 11 to 15% open on 2C02. The MFRV bypass valve fs - position indication.and MFRV
- (g _ l bypass valve controller output should be verified to be
. indicating ~ 11 to 15%. This valve position will establish
~ 5% of-rated main feed flow to the S/Gs.
b) Two condensate pumps are verified to be running on 2C02. The main generator _ lockout relays will initiate a trip of 2P-2C if 2P-2A is running
,q :
WP84989- SECTION VII - 1.0 PAGE 30 t
m ,,
d -
+w = v - -= .- --%, 9 ,,-y-- -,y -c - -, , , - - n--~w---%--e-,w-- ew - , - -, , , - ,
s
running. This will leave only two condensate pumps running, one pump on 2A1 and one pump on 2A2.
c
~) Both heater drain pumps are verified off on 2C02. Soon after a reactor / turbine _
trip, the heater drain pumps will trip on s
either 2T40 low pressure, 2T40. low level or high differential' pressure. If the heater drain pumps have not stopped, the operator should secure them.
- 2) The Emergency Feed Actuation Signal (EFAS) setpoint is 46.7%.' If S/G level (s). decrease below-this setpoint, the operator verifies.
proper actuation of the Emergency Feedwater (EFW) System. The EFW System should maintain-
-S/G 1evels around the EFAS setpoint with no operator action. Proper EFW actuation-is i
verified as follows:
a) The operator will verify both EFW pumps
-running. .The steam driven EFW pump,
-2P7A,. starts as soon as EFAS actuates.
o "The motor driven EFW pump, 2P7B, starts
! . /N: _
after a 90 second time delay.
l%)
WP84989' SECTION VII - 1.0 PAGE 31
. r:
f) . 1) By verifying proper EFW pump dis-
-\')
charge, the operator ensures that the pumps are capable of supplying water to the S/Gs.
- 2) By verifying EFW flows, the operator ensuces that water is being supplied to' the S/Gs... -- -.
b) When the operator has verified that S/G levels are being restored, manual control of the EFW block valves is-established and/or 2P-7A is secured.
Preference is given to securing 2P-7A to minimize condensate inventory de-pletion and to prevent possible over-cooling of the RCS. The combination-of a low decay heat input frem the-i.
reactor, 2P-7A running, a MFW pump running and restoring S/G levels to .
setpoint could reduce T,y, well below f its no-load setpoint. Additionally, -
EFW flow to individual S/Gs is more
- i. easily controlled by modulating 2CV-1205-1 and 2CV-1075-1 in the discharge of 2P-7B. OP 2106.06,
,v [D WP84989 SECTION VII - 1.0 PAGE 32 L . -
g
- g3 " Emergency Feedwater System Operations,"
b describes manual control of the EFW system and 2P-7A shutdown.
- 3) If required to limit the RCS cooldown, the operator will secure the remaining 1:FW pump.
- 4) If it is desired, the operator will isolate S/G blowdown by closing 2CV-1016-1 and 2CV-1066-1 on 2C17. With low decay heat levels, the feed rate necessary to sustain S/G blowdown may also result in possible overcooling of the RCS.
f S; *******************************************************************************
V GO TO STATEMENT *
- This statement directs the operator to the " INADEQUATE CORE COOLING" tab *
- ienced and no immediate recovery is indicated. The " INADEQUATE ~ CORE COOL- *
- possible establishment of condensate feed. If unable to establish some *
- type of feed t'o S/G(s), then direction to establish RCS feed and bleed is *
- provided. *
-?^T
{!'(,,)
WP84989 SECTION VII - 1.0 PAGE 33 6'
._ STEP 6: Verify Core Heat Removal:
.[%)
This safety function is satisfied by maintaining subcooled reactor coolant circulating through the core to remove decay heat. Heat removal is verified by ensuring RCS flow, RCS margin to saturation > 30 F and core exit thermocoupled indicating in Region I of Figure 2i A) RCS Flow:
- 1) Verify RCPs are running:
i dj-i. a) Check for the red lights above the pump handswitches indicating that the breakers are closed supplying power to the pumps, b) Checking that the pumps are drawing normal amperages. Normal amperage indicates that the pump is working on a subcooled liquid. Lov or erratic amperage indicates possible saturation
. -and flashing.
'h WP84989 SECTION VII - 1.0 PAGE 34 e
c) Checking for normal RCP AP values.
h3-q Normal AP reverifies the pump running and moving a subcooled liquid through the RCS. Low or erratic AP indicates possible saturation and flashing.
- 2) If the RCPs are not running, an effort _
should be made to restart one pump in each loops a) Appendix H lists the criteria which must be satisfied prior to starting a RCP.
D V
b) Starting a pump in a loop with an operable spray valve gives the operator better RCS pressure control.
c) Starting the second pump in an opposing loop will give the operator a second S/G for a heat sink and afford better flow distribution through the core.
L f
WP84989 SECTION VII - 1.0 PAGE 35 1
p, a
1 f-c 3) If RCPs cannot be restarted, natural cir-culation should be verified within 5 to 15 minutes of losing the RCPs. Natural cir-culation can be verified by the following indications:
a) aHot leg: temperatures (Tg) should stabilize and be slowly decreasing.
This indicates that the AT has in-creased enough to establish the required ficw to remove the decay heat being produced. ,
b) Cold leg temperatures (T ) are con-C stant or slowly decreasing. This indicates that the AT has increased enough to establish the. required flow'to remove the decay heat being produced.
These indications of TH "" C "#*
assuming a relative constant S/G
~
pressure is being maintained.
O j
WP84989 SECTION VII - 1.0 PAGE 36 e
,-~g .c) RCS AT h(T - Tc ) is less than 50 F.
.Q Actual testing and experience have shown that a AT > 50*F is abnormal and may indicate that something is resulting in a reduced natural cir-culation flow rate.
d) No abnormal differences between CETs and hot leg RTDs. If CETs increase much above T g, natural circulation flow may be insufficient.
e) There should be a continuous-demand for
("'j. EFW flow to maintain S/G levels.
~ %_/
f)
~
There should be a continuous demand ,
, for the operation of the atmospheric dump valve (s) or the S/G safety valves to maintain a constant S/G pressure..
If the S/Gs'are functioning as a heat sink for the RCS, there will be: steam flow from at least one location. If steam is released from the S/Gs, feed-water.must be added to maintain level.
,.-g.
WP84989 SECTION VII - 1.0 PAGE 37 m
p
,_s B) ' Verify RCS margin to saturation is > 30*F:
l ). ^
\./
The margin to saturation > 30'F ensures the reactor coolant is maintained subcooled. It includes allowances for possible inaccuracies and uncertainties of the margin to saturation calculators and their inputs. Circulating a subcooled fluid through the core is the pre-fee red method of core heat removal.
- 1) IF RCS margin to saturation is < 30*F:
a) Reverify RCS pressure control AND
/~S RCS inventory control safety functions, Y:
_ steps 3 and 4 of this tab:
In this step, the operator checks RCS pressure and inventory again to see if a condition may have developed since j these parameters were first checked, to cause a loss of control of these safety functions.
b) Monitor CET temperatures:
jM %'q-
'WP84989 SECTION VII - 1.0 PAGE 38
o
, _ - STEP 7~ _ Verify containment building integrity:
Containment integrity is verified in order to maintain the containment building as a fission product boundary.
A) This step directs the operator to verify that the containment building parameters are being maintained within allowable limits.
- 1) Average containment building pressure is verified to be 13 to 16 psia. This value is obtained by averaging the four safety
~
channel containment pressure indications on 2C33 (2PI-5601-1, 2PI-5602-2, 2PI-5603-3 and 2PI-5604-4). Verifying containment building pressure normal ensures that there is no large release of high energy fluid in progress inside containment.
+
- 2) Containment building temperature is verified to be s 140'F. This value can be obtained from 2TI-5663 or 2TI-5664~on 2C33 or T-5605-5 or T-5606-6.on the plant or CAPS computer. Verifying containment WP84989 -SECTION VII - 1.0 PAGE 39
-- .. -,.,,..,.n,--- , -,-,..,,,-,-n. . - - - .,n.. - , , , , - , , - -
,. building temperature normal ensures that l' -
there is no large release of high energy fluid in progress inside containment.
- 3) The trend recorders for containment pressure, temperature and humidity are
. monitored for abnormal trends. These recorders are 2PR-5601-1, 2TR-5660 and
'2MR-5660 on 2C33. The outputs of these recorders may provide the operator with indication of a medium to small primary or secondary fluid leak inside. containment.
B) IF containment building parameters are abnormal:
This step'provides guidance to the operator in the event that containment building parameters are abnormal.
- 1) The RCS pressure control'and RCS inventory control safety functions are to be re-verified. These safety functions are Steps
.3 and 4 of this tab. This re-verification is an attempt to locate the cause of the abnormal containment conditions.
i,.) '
WP84989 SECTION VII - 1.0 PAGE 40 i._
s
- 2) This step verifies that the containment building cooling fans, 2VSF-1A/1B/lC/1D, and the main chill water system are operating. This ensures that the abnormal containment parameters are not due to the loss of the containment cooling fans.
,a) If the main chill water system is not
-t operating or is inadequate, it may be necessary to align service water to the containment cooling fans.
STEP 8 Verify HOT STANDBY conditions are being maintained:
This step is intended to be a check of key plant parameters and' equipment that are required to maintain HOT STANDBY conditions.
A) Adequate shutdown margin for' Mode 3 is verified per OP 2103.15, " Reactivity Balance Calculation."
B) The pressurizer pressure control system is verified to be controlling RCS pressure at the deLired setpoint.
c) The pressurizer level control system is verified to be controlling pressurizer level at the
' programmed no-load level (~ 41%).
- 1) Adequate VCT level and pressure are verified.
r WP84989 SECTION VII - 1.0 PAGE 41 e
. .. = _ _
,_. D) The SDBCS is verified to be controlling T,y, at s !
\'f -
~ 545'F and S/G pressure ~ 1000 psia.
'E) RCS margin to saturation is verified to be 2 30*F.
F) At least one EFW train (preferably 2P-7B) is verified to be operating with S/G levels being manually controlled at ~ 70%.
- 1) If possible, the SU/BD DI effluent should.
be aligned to the EFW pump suction. This is done in.an effort to conserve CST water and prevent overfilling the condenser hotwell.
G) The proper operation and alignment of the main
<A~i feedwater and condensate system is verified as
(). follows:
- 1) Both MFW pumps should be secured and should be on.their turning gears. The MEW pump recire valves should both be closed.
- 2) One main condensate pump should be running-providing short path cleanup flow through a SU/BD DI.
- 3) Both heater drain pumps should be secured.
H) Condenser vacuum is verified to be normal and at least'one circulating water pump is verified to
~
be nonmal to establish support systems for SDBCS bypass valve operation.
q(~- -
WP84989 .SECTION VII - 1.0 PAGE 42 m
---, ..-- +- - . - - - - y -+ e----yy,,-,,,- y*va9-, - , + - - , - rw yw-vm-y-+-,,------ --.g ----ee,- -,,~9,-- - e- -- - t-- -
I) Verify feedwater and S/G chemistry are being
( /
maintained as per OP 1000.43.
- 1) The operator should monitor feedwater and S/G chemistry and align hydrazine for oxygen scavenging and corrosion control.
- 2) If feedwater cleanup is necessary, OP 2106.16 instructs the operator how to align for long path cleanup. The < 130'F limit is provided to prevent damage to the DI resin.
J). The main turbine generator should be secured as
,f T follows:
V.
- 1) The motor suction oil pump and the turning gear oil pump are verified to be running.
- 2) The main turbine bearing oil lift pumps may be started, if desired.
- 3) All turbine, extraction line and MSR drains to the main condenser should be opened.
- 4) 2CV-0400 and 2CV-0460 should be closed to secure main steam to the MSRs to minimize RCS cooldown.
- 5) The main turbine lube oil cooler outlet temperature should be reduced by adjusting the setpoint of 2 TIC-1602 on 2C11 to 90*F.
r~w WP84989- SECTION VII - 1.0 PAGE 43 e
p,4 6) When zero shaft speed is reached:
-t o a) The main turbine bearing oil lift pumps are verified running.
b) The main turbine turning gear motor is verified to be running.
c) The main turbine turning gear is i verified engaged.
l
~,' .
1 STEP 9 Perform applicable ANO procedures: I This step directs the operator to the applicable ANO 1
1 procedures (s) to maintain or establish the desired plant conditions.
. %)()
A) Section 6.0 of OP 2102.06, " Reactor Trip Recovery," should be completed anytime a reactor trip has occurred.
B) .The plant will be operated, as directed by plant management, using one of the following procedures.
- 1) A plant startup will be performed per OP 2102.06, " Reactor Trip Recovery."
- 2) Hot. standby conditions will be maintained per OP 2102.02, Step 11.32.
- 3) A plant cooldown will be performed per OP 2102.10, Section 8.0.
- 4) A natural circulation cooldown of the plant {
- (~' will be performed as per Abnormal OP 2203.13.
- . 5 L-WP84989 SECTION VII - 1.0 PAGE 44 e
,n,,.---ww- ,,-
- w
~
7s - 2.0 EMERGENCY REACTIVITY CONTROL RECOVERY ACTIONS
.O 2.1 Operational Goals
-The operational goal of the Emergency Reactivity Control tab is to provide the operator with guidance directed towards recovering the reactivity control safety function. The reactivity control success criteria are chosen to provide assurance ofLa reactor shutdown using negative reactivity from Control Element Assemblies (CEAs) insertion and/or boron addition to the Reactor Coolant: System (RCS).
2.2 ~ Description of Emergency Reactivity Control A loss of reactivity control is characterized by inadequate insertion of negative reactivit.y by the CEAs to provide
~ adequate Shutdown Margin (SDM).
Some possible causes for a loss of reactivity control are:
A. A Reactor Protection System (RPS) failure to automatically initiate a reactor trip when two or more safety grade instrument channels indicate that a plant parameter has -
exceeded its normal reactor trip setpoint.
B. Mechanical or electrical failures which prevent required sets of trip circuit breakers (TCBs) from opening to de-energize CEDMCS buses (2C70 and 2C71).
J' C. Mechanical failures in CEA drive mechanisms which prevents the insertion of all CEAs.
UF84989 SECTION VII - 2.0 PAGE 1 s
s-7_ , D. Mechanical binding of CEA(s) inhibits insertion.
U Failure of the RPS to cause a reactor trip has traditionally been referred to as an Anticipated Transient Without Scram
'(ATWS). The ANO-2 RPS is designed to preclude a single failure condition that will prevent a full reactor trip.
L Multiple failures of redundant RPS-components have'been
. identified which may result in the failure of all or half a :of:the rodsrto insert. However, the~ probability for a multiple failure condition within the RPS, which could
. result in a failure to cause a reactor trip, is extremely low because of the diversity of sensed parameters and the large number of failures required.
^
f' U) -
The ANO-2 Reactor Trip Circuit Breaker System is also designed to preclude a single failure condition which will prevent a full reactor trip. Multiple failures in the TCBs have a slightly higher probability of preventing a full reactor trip than would failures of the RPS or CEA travel ability. Multiple failures of TCB components (i.e., UV-trip devices, shunt trip devices, or mechanical failures) would be required to prevent all of the CEAs from being
, inserted into the core.
The failure to trip of any two TCBs in series will maintain power to one of the two Control Element Drive Mechanism
('
-(_
-(CEDM) power supply cabinets, thus maintaining approximately
- WP84989 SECTION VII - 2.0 PAGE 2 m
half the CEAs in the withdrawn position. The insertion of I,')
half the CEAs into the core would provide sufficient.SDM for short-term considerations _and allow the operator time to take necessary actions required to insert the remaining CEAs or to inject boron to provide necessary SDM.
Operator actions in the Emergency Reactivity Control tab are directed towards de-energizing the CEDMs by any available means to allow the CEAs to be inserted into the core.
Emergency boration is also immediately started to add
, negative reactivity to the reactor and provide shutdown capability should the operator be unable to fully insert all CEAs.
' y()
Emergency Reactivity Control Recovery actions are continued until all CEAs are inserted into the core'or until the reactor is. shutdown and the Technical Specification SDM is attained. Operator actions should also be taken to insure s_-
all other safety functions of the Reactor Trip Recovery Tab are being satisfied concurrent with the Emergency Reactivity Control Safety Function.
F 4 *%
\_)
WP84989 SECTION VII 2.0 PAGE 3 6
,w-s e y e e.-----N'-e" " ' - + " " * " * ' ' " ' ' ~ ' ' ~~ ^ "
. - vj; .
4 1
l i
,s .n 2.3 'Sadety Functions Affected
!-) 4' 1 Entry into the Emergency Reactivity Control tab is based on an !
- inability to satisfy the reactivity control safety function.
Depending on the severity of the loss of reactivity control and
^
any other system failures which might occur, all other safety functions may be affected. Special attention should be given s
eo ,
~to RCS; heat: removal because of the-importance of maintaining an
- adequate heat sink -to remove all-heat generated by the core until the reactor can be shutdown.
2.'4. Major Parameter Response A) Reactor Power Reactor power, in a situation where a reactor trip is called for but not achieved, will be initially controlled
~
- y-') by the secondary system steam demand. If a loss of J\ J ~
reactivity control is accompanied by a turbine trip, the Es, steam dumping capacity will be limited to available SDBCS valves and main steam line safeties.
This limited heat removal capacity will cause a rapid increase in RCS and core temperature. The rapid increase.
+ .
in RCS and core temperature will insert negative reactivity and reduce reactor power through the effects of moderator temperature and Doppler coefficients. Reactor power should stabilize 1at a_value determined by the amount of steam demand on the secondary system.
1
- p"h
-WP84989 SECTION VII - 2.0 PAGE 4 6
3
rrl- -
fg b , .
r t # ,5 The insertion of1CEAs into the core or the injection of 7]i
- 5
^ -
. concentrated boric acid into the RCS will provide a reduction of ' reactor power to decay heat levels.
B)' RCS Temperature
". ~ .RCS temperature can increase rapidly, depending on the
, , ?,
severity of the' loss of reactivity' control transient and other system failures which might occur. The magnitude of the'RC'S temperature increase and the value of temperature.
' stabilization will be a function of the RCS heat removal capability and the-response time of the SDBCS system.
s'N4.-
C) Pressurizer. Pressure and Level Pressurizer pressure and level response will be a function
- of~RCS-temperature.. If the transient causes a significant.
k
. increas, e in RCS temperature and.RCS heat removal. capabilities are limited, the resultant RCS fluid' expansion could cause
~
- pressurizer-pressure
- and level to increase rapidly. This increase:in RCS pressure'and inventory could cause the pressurizer code safety valves to lift and the pressurizer
'to become filled with water. Should the RCS ' temperature ' ,
. continue to increase, the capacity of the code safety valve
.could be exceeded and a subsequent pressure spike to occur.
p . x while the RCS experiences a loss.of inventory. through.the
[ @ - safeties'. The loss of RCS inventory is extremely detrimental
/
A '
in--this situation since the RCS pressure will be above the
~
i@
W ,
/Jc '
. shutoff headiof the high pressure safety injection pumps.
ty ,
- {t l(V. i i-N >
.i; WP84989'- SECTION-VII.- 2.0- .PAGE 5 w- .
} '
.., m , _ . _ -
4 -
F b
- -- l D) Steam Generator Pressure and Level l
!{^c-)~
Steam generator (S/G) pressure and level response will be j
a' function of the following:
- 1) Rate and magnitude of RCS temperature increase.
- 12) - Automatic or manual initiation of a turbine trip.
3). Available steam dump capacity.
4)' S/G safety valve setpoints. . . - -
'5)- ; Ability-of Feedwater Control: System (FWCS) to 3
~f
. maintain sufficient feedwater flow to meet the steam demand generated by an increase in RCS temperature.
'The~ ability to maintain. adequate RCS heat removal (i.e.,
heat sink) is critical for a loss of reactivity control transient.: S/G pressure and level control ~are an integral-t s -
part of the RCS heat removal safety function. Depending on'the severity and initiating cause of the loss of reactivity: control, S/G pressure and level may respond in different ways to the transient.
The response of 5/G pressure and level will be directly1
~
dependent on whether an automatic or_ manual turbine-trip is initiated and the ability of the FWCS to maintain sufficient S/G 1evel to support the RCS heat-removal safety function. If the transient involves a. turbine trip and a Reactor Trip Override (RTO) signal to the FWCS, steam pressure will increase to the opening setpoint for SDBCS valves. If the available SDBCS valve capacity is
- WP84989 SECTION VII - 2.0 PAGE-6 t
e
.=
,_-v.-.m,. , - . - - * =v
7 not adequate to control the increase in RCS temperature,
~
steam pressure may. reach the S/G safety valves setpoint and the safety valves will open to control steam pressure.
! - The RTO.will cause the FWCS to limit MFW flow to ~ 5%. flow, and sufficient S/G level may not be maintained without appropriate operator actions.
3 7
I t
~
- L-
?.
. WP84989- SECTION VII - 2.0 PAGE 7 e
.-m,. _y., -.-__,
,( 1
~2.5 Bases for Emergency Reactivity Control Actions STEP 1: Ensure that power is removed from the Control Element Assemblies (CEAs):
This step addresses the actions required if the manual and/or automatic reactor trip signals fail to de-energize the CEAs. Multiple failures would have to occur for.this condition to exist, but the consequences are so severe it must be addressed. The operator will first be directed to attempt to open all Trip Circuit Breakers (TCBs) via the manual reactor trip push buttons. If this action fails to de-energize the CEAs, the CEDMCS M/G sets will be de-energized. These actions will ensure that all (V 3 power is removed from the CEAs.
A) Push both manual reactor trip push buttons on 2CO3 AND 2Cl4 to open the TCBs:
These pushbuttons will energize a shunt trip coil and de-energize an undervoltage (U/V) trip coil on each TCB. This provides two independent trip actuations for each TCB and should result in the opening of all of the TCBs (excluding TCB-9).
If at least cne appropriate set of the TCBs open, power will be removed from the CEAs. This may be- ,
1 verified by observing that the CEDMCS U/V relay
[) .. indicating lights on the TCB status panel, 2JI-9059 v-WP84989 SECTION VII'- 2.0 PAGE 8 e
y ..-e -
e, + -
--7 ,q.
t h on 2C14, are out. The phase current indicating
' ~'^
lights on the TCB status panel should also be out.
B) IF unable to de-energize the CEAs by opening the TCBs, de-energize the CEDMCS M/G sets by opening the following breakers on 2C10:
- 1) 2B7 feeder breaker 2B712 AND
- 2) 2B8 feeder breaker 2B812 If the TCBs were not opened and the CEAs not de-energized by pushing the manual reactor trip push buttons, de-energizing the CEDMCS M/G sets j"'g - will remove power from the CEAs. This method of
-:q de-energizing the CEDMCS M/G, sets was chosen because it can be done immediately from the control room. The operator should be aware'that opening breakers 2B712 and 2B812 will result in the loss of 2B7 and 2B8. This may result in the loss of some desired non-vital load. However,
^
i; the operator should not hesitate to take this t~
action if required.
Five non-vital MCCs will be lost if 2B7 and 2B8 are de-energized: 2B26 (the portion supplied by 2B7), 2B71, 2B81, 2B85 and 2B86. Some of the L
- more important equipment lost will be "C" n) - CCW WP84989 SECTION VII - 2.0 PAGE~9 l ..
~
I i
i
- -c pump, both ACW booster pumps and the control l'~')
room ventilation system. Loss of power to 2B86 will result in the loss of power to both circulating water pump discharge valves. Loss of power to a single circulating water pump discharge valve will normally result in that
' ~
'circul'ating water pump tripping after a 5.5 minute thne delay. Due to the logic used in the circulating water pump controls, loss of power to both circulating water pump discharge valves
. should not result in the loss of the pumps.
However, this condition will result in the loss of the ability to manually stop the circulating
(-)_ water pumps from the control room (2C14) or from u/
2C125.
After the CEAs have been verified to be' fully
- inserted, the operator should re-energize 2B7 and 2B8.
- ^ GO TO STATEMENT *
-
- This statement directs the operator back to the " REACTOR TRIP RECOVERY" tab *
- if,the above actions were successful in the insertion of all, or all but *
- failed to fully insert into the core.
4 p;
'WP84989 SECTION VII - 2.0 PAGE 10 e -
'rw -
- er e e y e - -<*-,# 3 e-e-a,+,.~r-em., -
p,p--,--,,-w,---ee i---+-ow- , e-
f- , STEP 2: Commence ~ emergency boration from panel 2C09:
k)'
This step directs the operator to commence emergency boration if two or more CEAs have failed to insert.
Emergency boration will consist of the injection of 2 1731 ppm boric acid at 2 40 gpm. The requirement to emergency borate when two or more rods have failed to insert'is to maintain SDM Technical Specification (3.1.1.1).
.A) Line up boric acid to the charging pump suction from one of the following sources:
- 1) Boric Acid Makeup (BAM) tank gravity feed.
a) Open 2CV-4920-1 (2T-6A) OR 2CV-4921-1 (2T-6B) (BAM tank gravity feed valves).
p-V This source of boric acid is listed first due to
, its ease of alignment and due to its high boron concentration. _The BAM tanks are the preferred-source of boric acid for emergency boration.~ The RCS boron concentration can be increased faster by charging BAM tank contents than by charging RWT contents.
~b) Open 2CV-4916-2 (BAM pump to charging-pump suction) v WP84989- SECTION VII 2.0 PAGE 11 e
p c) Verify closed 2CV-4926 (boric acid
, j-q i'_f' flow control valve):
Since the BAH tanks are the preferred source of boric acid, the BAM pumps are a
listed as the second option.
.r . ..
4 3)' ' RWT (Refueling Water Tank):
. r: a) Open 2CV-4950-2 (RWT to charging pump)
, If the operator desires, the RWT may be lined up to the charging pump suction.
This.is an acceptable source since the RWT
.is maintained with a 2 1731 ppm boron concentration.
B) Close 2CV-4873-1 (VCT outlet valve):
The Volume Control Tank (VCT)-outlet valve must be shut to ensure that the charging pump (s) are taking a suction from the 2 1731 ppm boric acid source and not from the VCT.
c) Verify at least one charging pump is running and that charging header flow (2FIS-4863) is 2 40 gpm:
This step ensures that the emergency boration
( requirement of 2 40 gpta is satisfied.
'WP84989 SECTION VII - 2.0 PAGE 12 e
wi_.
(~
"~j
\
~] NOTE l l Emergency'boration is to continue until condition in Step 3 is satisfied. l l The desired result of the emergency boration is stated in this note because [
- l the next GO TO statement will direct the operator back to the Reactor Trip l l Recovery tab with emergency boration still in progress. l GO TO STATEMENT *
~
- This statement directs the operator to Step 2 of the " Reactor Trip Recovery"*
, s
- tab' after emergency boration is in progress.
- STEP 3: Continue Emergency Boration until adequate shutdown O
~} for Mode 3 conditions exist per OP; 2103.15:
OP 2103.15, " Reactivity Balance Calculation," is used to determine the required RCS boron concentration' to provide the actual and available shutdown margins needed. Another calculation is made to determine how much boric acid must be added to achieve this required RCS boron concentration. Emergency boration is continued until this amount of boric acid has been added. The RCS should be sampled to verify that the required boron sample has been established.
i WP84989' SECTION VII - 2.0 PAGE 13 4
L_
- ~-
l 1 r ~3 - 3.0 DEGRADED POWER RECOVERY A TIONS s 3.1 Operational Goals The primary operatione.1 goals of the Degraded Power Recovery Tab are to ensure the operability of the Emergency Diesel Generators (EDG) and the stabilization of vital plant parameters using
~I equipment powered from the EDGs.
The secondary goals are the restoration of a stable off-site power source that allows the plant to be returned to a Hot Standby condition with forced RCS flow.
3.2 Description of Degraded Power A Degraded Power condition is a loss of normal AC power to the r~
(~TL , plant systems and equipment from both the off-site power < grid w) and the main turbine generator with at least one Emergency Diesel Generator (EDG) automatically starting and providing electrical power to its associated ESF electrical system.
Some possible causes of a Degraded Power situation are startup o
transformer (#2 and #3)ifailure, on-site AC distribution system failures, or off-site grid failures caused by severe weather, natural phenomena, or electrical-mechanical equipment failure.
^
ri:
The loss of electrical power will initially include a loss of all electrical equipment with the exception of vital instrumenta-tion supplied by battery powered inverters, emergency DC lighting, WP84989 'SECTION VII - 3.0 , PAGE 1 t
w-
L V
. , se' DC control power for electrical breaker operation and indication,
^\ l
' ' ~ '
DC powered solenoid valves, and DC powered pumps.
- y. Electrical power will not be available to CEDMs, reactor coolant pumps, main condensate pumps, main circulating water pumps, pressurizer pressure and level control systems, feedwater Econtrol systems, the steam dump and bypass control system, and instrument ~ air compressors Under these circumstances, :
the plant will experience a simultaneous reactor trip, loss of'
!t.
load, loss of feedwater flow, and a loss of forced flow cooling.
The diesel generators will be automatically started by an
-undervoltage condition on 4160 volt ESF buses 2A3/2A4 and 480
(y v
volt load centers 2BS/2B6. The diesel generators should be supplying their respective 4160 volt ESF buses (2A3/2A4) within
~ 15 seconds of the undervoltage condition and the required Engineered Safety Features (ESF) components should be sequenced on the ESF buses.
When ESF buses are re-energized, electrical power is restored to the pressurizer pressure and level control systems, feedwater control systems, and the steam dump and bypass control system.
This allows the operator to take actions to stabilize plant parameters and maintain Hot Standby conditions while attempting to restore an off-site electrical power source.
k) '
Ly.' WP84989 .SECTION VII - 3.0 PAGE 2 e
p- Since no reactor coolant pumps will be available uatil an -
)_ .
off-site electrical power source is made available, natural circulation flow must be established in the RCS to transfer decay heat from the core to the S/Gs.
Adequate RCS heat removal is maintained by ensuring that the S/Gs are available as a heat sink. Emergency Feedwater (EFW) is provided by the steam driven EFW pump (2P-7A) and the electric driven EFW pump (2P-7B) which is powered from Emergency Diesel Generator 2DGl. Heat removal from the S/Gs must be accomplished by using the SDBCS atmospheric dump valves or the main steam line safety valves because the main condenser is unavailable.
N Actions should be taken as soon as possible to restore an
(^N L.
off-site power source to provide electrical power to the non-vital portion of the plant electrical system. When the non-vital electrical system is restored, support systems such
. as Component Cooling water (CCW) and Instrument Air (IA) should be placed in service to provide valve control and cooling water to RCPs, letdown heat exchanger, and other RCS support systems.
Secondary plants systems, such as circulating water, condensate, and vacuum systems, should be placed in service and a vacuum re-established in the condenser to allow turbine bypass valves
, to be used for RCS heat removal.
f'8 b] .
WP84989 SECTION VII - 3.0 PAGE 3 G
m.
- -~ . RCPs should be re-started when seal temperatures have been stabilized and start interlocks are satisfied to provide RCS forced flow cooling.
If a degraded power condition is to exist for an extended period, condensate makeup inventory and diesel fuel oil inventory should be evaluated and consideration should be.given to performing a natural; circulation.cooldown to shutdown cooling operation:before condensate makeup inventory is depleted.
3.3 . Safety Functions Affected The electric power safety function is the primary safety function affected by a degraded power condition. The proper fulfillment of this safety function is dependent on the proper
' automatic operation of the EDGs. The proper operation of EDG f('_]
s -
powered systems and equipment should provide for adequate control of all other safety functions.
3.4 Major Parameter Response A) Reactor Power Regardless of the cause of a Degraded Power Condition, a reac-
. tor shutdown will be initiated by the insertion of the Con-trol Element Assemblies-(CEAs). A rapid decrease in reactor power and a negative startup rate will be observed. This rapid decrease in reactor power will be followed by a de-crease in indicated power (at approximately -1/3 decade per minute) until the suberitical multiplication level is reached.
O; q
WP84989 SECTION VII - 3.0 PAGE 4 b..
r a
u >
~
5)~ RCS Temperature
,-v
- k., g)]. '.
In the absence of forced RCS flow, RCS temperature will be
, a function of.the ability of the RCS and steam generators
._ to remove heat from the core by natural circulation flow.
Natural circulation' flow is governed by the amount of decay heat, component elevation *, primary to secondary heat; transfer, loop flow resistance, and the amount of voiding in the RCS.
RCS average temperature (T,y,) will _ initially decrease due
, to the reactor-trip. After the trip, hot leg (TH } ""
' cold leg-(TC ) temperatures will increase slowly until T c
reaches the saturation temperature which corresponds to
,,q :
the lowest. steam generator _ safety valves pressure L) '
setpoint. The T Htemperature will continue _to rise slowly.
until sufficient temperature differential (AT) is established to provide the required driving head for
- i. natural circulation flow through the RCS. Temperatures.
4 will stabilize at these levels until operator actions are-
-taken to place.the SDBCS atmospheric dump valves in ser--
n
.vice to return RCS temperatures to Hot Standby conditions.-
(C) . Pressurizer Pressure and~ Level
' The response of pressurizer pressure and level will be sin--
' ~
ilar to that following any reactor trip.. Pressure and level will. initially decrease due to a decrease in RCS temper-l ature.,
o
- i. WP84989'
- SECTION VII - 3.0 PAGE 5 O
t
I- ~
_ g-s Following the re-energization of the ESF electrical
~>
bus (es) by the EDG(s), pressurizer proportional heaters, charging pumps and auxiliary spray valve should be available for use to return pressurizer pressure and level back to normal Hot Standby conditions.
Letdown system flow should be isolated due to the loss of component.. Cooling: Water (CCW) flow to the letdown heat exchanger.
Pressurizer pressure should be monitored to insure that adequate margin to saturation is maintained to maximize 1
the effectiveness of natural circulation flow in the RCS.
(D) Steam Generator Pressure
(")T
\..
Steam generator (S/G) pressure will initially increase due to the termination *of steam flow to the turbine. Steam generator safety valves will open to control S/G pressure until operator actions are taken to place the SDBCS atmospheric dump valve (s) in service.
Steam dump capabilities to the condenser will be unavailable
, due to a loss of power to the main circulating water pumps and subsequent condenser vacuum loss.
(O> -
WP84989 SECTION VII - 3.0 PAGE 6 O
w..
4 E
7: s > . Instrument air compressors will not be available due to
'~'
.their non-vital electrical power source which will be de-energized during a degraded power situation. Instrument air may.be available from Unit I (compressors powered from EDGs) through the instrument air cross-connect. If no instrument air pressure is available, atmospheric dump valve (s) will require local manual operation to control S/G pressure and RCS temperature.
(E) Steam Generator Level
' Steam generator level will initially decrease rapidly following the reactor-turbine trip due to " shrink." If S/G levels decrease to < 46.7%, the Emergency Feedwater Systen (EFW) will be actuated and will be available to restore S/G 1evels. The stema driven EFW pump (2P-7A) 1{ will start immediately and supply EFW to the S/Gs. The electric driven EFW pump (2P-78) will start ~ 90 seconds after the ESF bus 2A3 is powered by the EDG. p The normal Main Feedwater System will be unavailable t
'during a degraded power condition due to the loss of
. 'non-vital ~ powered components such as the Main Condensate Pumps, Heater Drain Pumps, and Main Feedwater Pump i
, Auxiliaries.
a.s . WP84989' SECTION VII - 3.0 PAGE 7-9 - m
j3 After verification of proper EFW system operationi manual N.) Jcontrol of EFW components may be required to prevent. excessive S/G feeding. _ Excessive feeding of the S/Gs.can result in RCS temperatures being reduced below the desired no load value. This decrease in RCS temperature could cause an excessive pressurizer level and pressure decrease. Maintaining S/G 1evel above the minimum required level' (~ <30%. wide range):for : adequate heat transfer is essential to maintaining natural circulation flow in the RCS.
-3.5- Bases for Degraded Power Recovery Actions STEP 1 , Verify that the Emergency Diesel Generator (s) (EDG) have auto started AND energized their respective J(~')
N 4160 volt AND 480 volt bus (es): t The EDGs should auto start on undervoltage and automatically energize 2A3 and 2A4. This action should provide vital AC power to the required safety equipment. A)' EDG(s)
- 1) Verify normal frequency AND voltage on 2C33:
4 L Normal' output frequency and voltage. for the EDGs should be 60 HZ and 4160 volts. s.
'WP84989 SECTION VII - 3.0 PAGE 8 e ,,r,m . e. w.r
m
,i^ '2) Verify closed the EDG output breakers 2A308 , i) '~'
and 2A408 on 2C33: The EDG output breakers-closed indication L (red light above handswitch) should be on. Further verification can be made by observing load on the EDG (amperage and KW indicated). B) Vital AC Bus (es)
- 1) Verify open the normal feeder breakers to 2A3 and 2A4. (2A309 and 2A409) on 2C33:
Verifying the normal feeder breakers open
) ensures that the EDGs are not supplying power to 2Al and 2A2. This could result in ' overloading the EDGs. -2) Verify normal voltage on 2A3 and 2A4 on 2C33:
Voltage on 2A3 and 2A4 should be ~ 4160 volts. O
'WP84989: SECTION VII - 3.0 PAGE 9 6
f') /
/ /
- 3) Verify energized 2B5 and 2B6 on 2C33:
a) Verify closed 2A301, 2B512, 2A401 and 2B612. b) Verify amperage indication on 2B5 and 2B6. 2B5 and 2B6 need to be energized so power will be available to the 480 volt safety equipment. Verifying closed the above breakers will ensure 2B5 and 2B6 are connected to 2A3 and 2A4.
- 4) Verify the vital Engineered Safety Features (ESF) Motor Control Centers (MCC) are
'~ '3 ,l energized by ensuring that their red indicating lights on 2C33 are lit:
The red indicating lights on 2C33 for the ESF MCCs indicate that the supply breakers for these MCCs on 2B5 and 2B6 are shut.
,a \_/
WP84989 SECTIO!I VII - 3.0 PAGE 10
=
-,ey - Service Water (SW) Cooling: . C)
V SW cooling is vital to'the continued operation of the EDGs. After the EDGs have re-energized 2A3 and 2A4, the SW pumps that were running prior to the loss of power should restart. The SW systems suction and return valve alignment should not be affected unless an ESF signal affecting them is actuated.
- 1) Verify open the EDGs SW outlet valves, 2CV-1503-1 and 2CV-1504-2 on 2C33:
The EDG SW valves receive an open signal _\sQ when the EDG comes up to speed or when the jacket cooling water pressure builds up to a pre-set value. These valves should open
. ,once power is restored to them from the EDGs.
- 2) Verify that the SW pump (s) have started on 2C16 and 2C17:
A SW pump for each SW loop should be running to supply cooling water to both EDGs. 1 (O - WP84989 SECTION VII - 3.0 PAGE 11 O b.._.
- -gg 3) Verify proper alignment of Loop I and
- L.)
Loop II SW: a) Verify SW pump suction from the lake or the emergency pond on 2C33. b) Verify a discharge path to the lake, the emergency pond or the cooling tower. c) Verify Loop I and Loop II discharge scu ':r** pressure indication, 2PIS-1417-1 and 2PIS-1423-2, is > 55 psig (low pres-sure alarm) and < 118 psig (high pressure alarm) on 2C16 and 2C17. s-The above alignment should ensure that j } cooling water is being delivered to the EDGs. D) If,one EDG fails to start, initiate actions, if possible, to return the inoperable EDG to service: If one of the EDGs failed to start, as time and the availability-of personnel permits, efforts should be made to place this EDG in service. Only one EDG is absolutely necessary. The f"% ' . L WP84989 SECTION VII - 3.0 PAGE 12 e
l s , l l
; -~_ operator should continue with the procedure LJ while others are working on this step. This step relies on the operator's experience and knowledge of the EDG controls to return an inoperable EDG to service. The possible failures of the EDG control system are too numerous to address in this procedure.
STEP 2: Restore pressurizer pressure to 21800 psia but s 2300 psia: RCS pressure control is required to keep the reactor coolant subcooled so that the coolant is in the
' ("%q.) preferred state to transfer heat from the core to the S/Gs. This step addresses the RCS pressure control safety function and supplies information to ensure that it is maintained within the desired band. '
During a degraded power situation, pressurizer pressure will be maintained by use of the proportional heaters and the auxiliary spray valve. The operator needs to be aware that if only one EDG is operating, the pressurizer pressure and level O. WP84989 SECTION VII - 3.0 PAGE 13 e
~
7 - control channels being powered by that EDG may need to be-selected to allow operation of the proportional ,
' heaters. Additionally, the heater cutout channel selector switch may need to be selected to the operable channel.
L A) -Restore the pressurizer proportional heaters to automatic operations r
- 1) Verify pressurizer level 2 29%: {
l Pressurizer level must be above the heater cutout level of 29% to allow the proportional ;
. heaters to be placed in service.
O
- 2) Place the pressurizer proportional heater handswitches on 2C04 to "0N" to regain control.of.the proportional heaters:
-When an undervoltage condition is sensed on ,
285 and 256 the proportional heater r breakers open. Placing the handswitches on I 2C04 to "ON" will close these supply breakers allowing the proportional heaters j to control pressuriser pressure. Pressurizer level must be > 29% to gain control of the proportional heaters. i WP84989 SECTION VII - 3.0 PAGE 14
,m, . _ _ , _ _ , __ . _ _ _ . . _ _ -- _ . - . . - - - - - - - - - - - - - - - - - - - - - - - - - - ' - - - - - - - - - - - - - - - " - ^ - ' - - ' - ^ " ^ ' - - ^ ^ ' - - ^ - - - ^ - - ^ - ' ~ ~ ~ - ' - - - - - - - - - - - - - - - - - - -
~ ~s 3) Verify that the proportional heaters are
- s
)
restoring pressurizer pressure to the desired setpoint , once pressurizer level has been stabilized, the proportional heaters should be able to restore pressurizer pressure to the setpoint. F B) Operate the auxiliary spray valve to limit ' pressurizer pressure to < 2300 psia: I Pressurizer pressure is maintained < 2300 psia
' I to avoid challenging the pressurizer safety
(g valves. This value is.the standard upper limit r i./ s for the RCS pressure safety function. I b i
- 1) Verify at least one charging pump is operating on 2C09 to provide auxiliary spray flow.
- 2) open 2CV-4824-2 (auxiliary spray valve) on 2C09 to allow minimal flow, thus pre-heating the auxiliary spray line.
- 3) Close 2CV-4827-1 and 2CV-4831-2 (loop I charging valves) on 2C09 to provide full flow through the auxiliary spray line.
iO
-v WP84989 SECTION VII - 3.0 PAGE 15 O
, .- .. -- ..._.n. _-- -. . - . . . . . . - . - . - - . . - - - - - . . - -
t L L
,s. 4) Close 2CV-4651 and 2CV-4652 (normal V(I' !
pressurizer spray valves) on 2C04 to ensure 7
,' full flow is directed through the auxiliary '
spray line. When using the auxiliary spray valve, finer 1 pressure control may be obtained .by throt-nt. tling 2CV-4651 or 2CV-4652 open and allowing auxiliary spray flow to be diverted back through the main spray line to the loop. This also will minimize the number of spray nozzle thermal cycles by eliminating the f
. c; need to open and close the auxiliary spray i
{y valve.
.,J , 5) ,
If the difference between pressurizer and , charging water temperature is > 200'F, as measured by pressurizer water phase temperature (2TI-4622) and regenerative
, heat exchanger.to RCS (2TI-4825), then logging of each sprpy cycle is required to ensure Technical Specification (5.7.1) is ,
maintained. ' 1
.i 7m i
(_ l , WP84989 SECTION VII - 3.0 PAGE 16
. t I
F i ' ( ~ STEP 3: Verify RCS inventory is being maintained: A) Isolate letdown on 2C09:- Letdown is isolated due to the loss of Component-Cooling Water (CCW) to the letdown heat exchanger.
-k4 f B) -Verify charging restored: , 1) Cycle charging pumps as necessary to maintain pressurizer level:
The charging pumps have a 50-second time delay before they can be started after-regaining power. - Since letdown is isolated, the pressurizer level, control-system cannot maintain pressurizer level. ' The charging pumps must be started and stopped to maintain pressurize'r level at approximately 41%. b lt ; s WP84989 SECTION VII - 3.0 g PAGE 17 4 % [ , b.
n
>x - f-q C)- Monitor VCT level and shift charging pump suction .)Q when necessary from 2C093-No power is available to the reactor makeup water pumps, 2P109A/B, during degraded power conditions.
Antalternate source of makeup must be provided to the charging pumps when the VCT level gets low. Either the refueling water tank (RWT) or a boric acid makeup (BAM) tank is an acceptable source of f makeup.
- 1) RWT:
,(~'( a) ' Open 2CV-4950-2 (RWT to charging pump rl%)
suction).
-b) Close 2CV-4873-1 (VCT outlet valve) to prevent, completely. draining the~VCT. 'i
- 2) BAM tank a) Open 2CV-4920-1-(2T6A) or 2CV-4921-l' (2T6B) (BAM tank gravity feed valves).
or Star't a'BAM pump, 2P-39A or 2P-39B, and open 2CV-4916-2 (BAM pump to
.w U l, . charging pump).
3 I
.e ~
.? ,
'WP84989 SECTION VII - 3.0 PAGE 18
- r: ,
i
-? +
5
. ,f-y b) Close 2CV-4873-1 (VCT outlet valve).
(,,J - Either!of the above sources should provide adequate makeup to maintain hot standby
.2 conditions.
i D) Monitor the following parameters for indication of loss of RCS inventory: The following indications are expected to remain operational during degraded power conditions.
)' ' 1) The S/G sample cooler radiation monitor (s)
{ , provide possible indication of primary to secondary leakage in the S/G. 2). -The containment area radiation monitor (s)^ are. a possible indication of RCS leakage inside containment. l
- 3) The containment sump level increasing is a possible indication of RCS or seccndary.
leakage inside containment. This indication is not addressed in the GO T0 statements since it is not a specific symptom of any of the accidents.
' WP84989 SECT, ION VII - 3.0 PAGE 19 e '
- a
(;' N /
.,-m *************w**************************************************************
U *
- GO TO STATEMENT This statement directs the operator to perform the "0VERC00 LING" tab in
- conjunction with this tab, when pressurizer pressure and pressurizer
- level are decreasing along with decreasing S/G pressure. The "Overcool
- ing" tab will provide the operator guidance in terminating the overcool *
- ing event to prevent MSIS and/or SIAS actuation. The reason the *
* " Overcooling" tab is done in conjunction with this tab is so the
- operators can continue efforts to restore off-site power while obtaining *
- guidance for terminating the cooldown from the " Overcooling" tab. It *
{ ,
- should be'noted that with a degraded power condition some of the valves
- 12
- addressed in the " overcooling" tab may not have power. These valves *
- may have to be operated manually. Upon completion of the " Overcooling" *
(~N
- tab, the operator continues the recovery actions for degraded power. *
. u. ****************************************************************x*********** 'Y; ') <
3 D <\= 4 f ' 4-t
/^%.
f v/ s WP84989 SECTION VII - 3.0 PAGE 20
,_s *******************************************************************************
GO TO STATEMENT *
- This statement directs the operator to perform the "MSIS" tab in conjunction
- with this tab when indications of a main steam leak or a feedwater leak *
- exist. Pressurizer pressure and level will be decreasing due to the
- reduction of RCS temperature. S/G pressure will decrease to s 751 psia due *
- to the cooldown of the RCS. The performance of this tab will provide
- guidance to the operator for satisfying the safety functions and
- controlling the plant with a MSIS present. The reason the "MSIS" tab is
- done in conjunction with this tab is so the operators can continue efforts
- to restore off-site power while ensuring proper plant response to the MSIS.
- It should be noted that with a degraded power condition, especially if only
- one EDG is operating, some of the equipment addressed in the "MSIS" tab may
- 1
('N not have power. This, however, should not prevent proper control of the
- x)
- plant unless other. failures, besides an EDG failure, occur. The operator
- should perform as much~of and as many of the steps of the "MSIS" tab as *
-* the degraded power conditions will allow.
I u hX.' b) WP84989 SECTION VII - 3.0 " PAGE 21 b... m _ j,,-,- . . , .--v. -,-r,e*--e-i yw'-*-m-"--"Y-+* " " " ~ * * * ' ' * - " * "
- s i
' + - -
- *' GO TO STATEMENT
- This statement directs the operator to perform the "S/G TUBE RUPTURE
- 3 GREATER THAN CHARGING PUMP CAPACITY" tab in conjunction with this tab when *
' ~ indications of a S/G tube rupture exist. Pressurizer pressure and level
- will be decreasing due to the loss of RCS inventory into the S/G. S/G
- pressure should remain constant since RCS temperature should not.bec changing. rSecondary= activity should be-increasing due-torthe leakage of *
-* contaminated reactor coolant into the S/G. The performance of this tab * '
will provide guidance to the operator for satisfying the safety functions *
*. arid controlling the plant with a S/G tube rupture present The reason the .* , *""S/G TUBE RUPTURE GREATER THAN CHARGING PUMP CAPACITY" tab is done in * *. conjunction with this tab is so the operatiors can continue efforts to
- I restore off-site power while ensuring proper plant response to the S/G
- 1 tube rupture. . It should be noted that with-a degraded power condition, * '
4 especially if only one EDG is operating, some of.the equipment addressed in *
~
[ the "S/G TUBE RUPTURE GREATER.THAN CHARGING PUMP CAPACITY" tab may not have *
- *. power. . This, however, should not prevent proper control of the' plant
- 4
' * -unless~other failures, besides an EDG failure,-occur. The operator should
- 1 . .
y-perform as much of'and as'many of the steps of the "S/G' TUBE RUPTURE
- i
' *- GREATER THAN CHARGING PUMP CAPACITY" tab as the degraded power conditions *
- will allow.
- t 4
g - WP84989 SECTION VII - 3.0 PAGE 22 um wW.
<m, 9- $-v. .v.y--,
t-e,- gw,a-y .y-%4.,-cyv-w,,. , -y, , , . , - . = .-..,-gy==v-,-,4 y.,e.,,-w-+---r,.,.g,,.w,,, , , . ,e.gg,mt,g.mq,...,.-<,,--tw+--*v-#v-P e e= wo -= m y n W * *- **vre++mwy-^
(v)
- GO TO STATEMENT *
- This statement directs the operator to perform the "SIAS" tab in conjunction *
- With this tab when indications of a loss of coolant accident (LOCA) exist. *
- Pressurizer pressure will decrease due to the loss of RCS inventory. *
- Abnormal. pressurizer level indications will exist due to the loss of RCS *
- inventory. If the leak is not in the pressurizer, pressurizer level should *
- decrease as expected. If the leak is in the pressurizer steam space or *
- 1evel indication piping, the pressurizer level indications may increase or *
- indicate differently. In any case, pressurizer level should not remain *
- constant during a LOCA. S/G pressure should remain constant since RCS *
- temperature should not be decreasing below the no load value. Secondary *
- activity should not increase since there is no primary to secondary leakage.*
./^
- The performance of this tab will provide guidance to the operator for *
. Q}.
- satisfying the safety functions and controlling the plant with a LOCA in *
- progress. The reason the "SIAS" tab is done in conjunction with this tab *
- is-so the operators can continue efforts to restore off-site power while *
- ensuring proper plant response for the LOCA. It should be noted that with *
- a degraded power condition, especially if only one EDG is operating, some *
- of the equipment addressed in the "SIAS" tab may not have power. This, *
- however, should not prevent proper control of the plant unless other *
- failures, besides an EDG failure, occur. The operator should perform as *
- much of and as many of the steps of the "SIAS" tab as the degraded power
- conditions will allow. *
*******************************A***********************************************
.. /~ %
-U WP84989 SECTION VII - 3.0 PAGE 23 e
.. s, STEP 4: Verify adequate RCS heat removal by verifying proper operation of the EFW system and the SDBCS or the S/G safety valves:
The-removal of heat from the RCS is necessary to ~ maintain long-term core heat removal. This step verifies operation .of.. die. systems required -to . . . maintain a S/G as a RCS heat sink. Core heat removal is not verified in this step because natural circulation flow may not be fully established at this time. A) If S/G levels decrease below 46.7% verify proper actuation of the EFW system f' s (j The Emergency Feed Actuation Signal (EFAS) setpoint 13 46.7%. If S/G level (s) decrease below this setpoint, the operator verifies proper actuation of the EFW system. The EFW system is the only method of S/G inventory control during degraded power conditions. The EFW system should maintain S/G levels around the EFAS setpoint with nu operator action.
~s %-]
WP84989 SECTION VII - 3.0 PAGE 24 e p , t ., - - - + , - - -%w. , , e , . - - - - ----m < - .. . - - - -- w- c --- . ve 4
- 1) Verify that the EFW pumps are running on'
~
2C16/2C17: Since 2CV-0340-2 (steam supply to 2P-7A) is a DC powered MOV, 2P-7A starts as soon as EFAS actuates. The motor driven EFW pump, 2P-7B, starts after a 90-second time delay once 2A3 is re-energized. a) By verifying-proper EFW pump discharge pressure, the operator ensures that the pumps are capable-of supplying water to the S/Gs.
/"~ b) By verifying EFW flows, the operator
- (
ensures that water is being supplied to the S/Gs.
- 2) When the operator has verified that S/G levels are being restored, manual control of the EFW block valves is established and/or 2P-7A is secured. This action is taken to prevent possible overcooling of the RCS.
/^N MPS4989 SECTION VTI - 3.0 PAGE 25 e
GO TO STATEMENT
- This statement directs the operator to perform the " INADEQUATE CORE COOLING"*
tab in conjunction with this tab if a complete loss of feed is experienced *
-* and no immediate recovery is indicated. During degraded power conditions, *
- S/G feed is limited to EFW, 2P-7A and/or 2P-7B. If both of these sources *
-* are lost, the operator uses the " INADEQUATE. CORE COOLING" tab for guidance
- to provide possible EFW restoration:or?feedrand-bleed cooling of the core.
- The reason the " INADEQUATE CORE COOLING" tab is done in conjunction with
- lthis. tab is so the operators can continue efforts to restore off-site power
- while. obtaining guidance from the " INADEQUATE CORE COOLING" tab for *
*- providing core cooling. It should be noted that with a degraded power
- condition, some of the equipment addressed in the " INADEQUATE CORE COOLING" *
() (_/ tab may not have power. The operator should perform as much of and as
- many of the steps of the " INADEQUATE CORE COOLING" tab as the degraded *
- power conditions will allow. If the ECCS vent isolation valves are opened,
- the operator should perform the "SIAS" tab in conjunction with tab.
- f~h N)
WP84989 SECTION VII - 3.0 PAGE 26 6 N - '.e
L , 4 s"St 3) Isolate blowdown by closing 2CV-1016-1 and 2CV-1066-l'on 2C17: 4
.S/G blowdown is isolated to prevent , 's possible overcooling of the RCS and because .the system is no longer capable of handling it. During degraded power conditions, the S/G blowdown pumps have no power available and a vacuum canr.ot be maintained in the main condenser.
B) Verify S/G pressure and RCS temperature (cold-1 leg temperature, Tc) are being maintained: By verifying that S/G pressure and Tg are being. maintain'edi the operator ensures that sufficient I' main steam is being removed from the S/Gs to
-remove core decay heat from the RCS.
k I a 1 C a l d' . WP84989 SECTION VII - 3.0 PAGE 27
,m 1) If required, reset SDBCS per OP 2105.08, d'
Section 6.7. The temporary loss of AC power to SDBCS may result in the system having to be reset before automatic operation can be established. Manual operation of the SDBCS valves should be possible_before the system is reset.
- 2) If necessary, attempt to maintain Instrument Air by cross-connecting with Breathing Air OR Unit 1 Instrument Air If Unit 1 Instrument Air is available, it can be aligned to supply _ Unit 2 Instrument Air by opening 2CV-3004 or 2CV-0315 on 2C14. If Breathing Air is available, it can be_ aligned to supply Unit 2 Instrument Air by aligning Breathing Air to Unit 1
, Instrument Air and opening 2CV-0315. - 3) Operate atmospheric dump valve (s)
(2CV-1001, 2CV-1051, 2CV-0301 or 2CV-0305) to control S/G pressures at ~ 1000 psia and T at ~ 545'F:- O: WP84989 SECTION VII - 3.0 PAGE 28 m
r vv' s
- r s. a) If instrument air is available, (f
establish control of the atmospheric dump valve (s) from 2C02: b) If instrument', air is not available, manually operate the atmospheric dump
, valve (s) locally:
4 During a degraded power situation, the main condenser is not available to dump steam into. The SDBCS atmospheric dump valves should be used. Since a malfunctioning downstream () atmospheric dump valve can be isolated by closing the MSIVs,.the use of these valves should be given preference over the upstream atmospheric dump valves. Additionally, better communication and easier access is available for manual operation of the downstream dump
-valves. The atmospheric dump valves are provided with a manual operator that allows manual opening of these valves. The valves still rely on - spring force for closing. This feature is used when instrument air is
() not available for valve operation. WP84989 SECTION VII - 3.0 PAGE 29 6
'i
, h . f' The no-load RCS temperature is 545'F.
(sl: Controlling S/G pressure at ~ 1000 psia will maintain this desired RCS temperature. T is used for RCS c temperature indication instead of Tave because during natural circulation cooling, T g-more closely corresponds to S/G saturation temperature and any i changes in the amount of heat removal are first seen on T c. GO TO STATEMENT *
- This statement directs the operator to perform the " Overcooling" tab in *
~ {v~')
- conjunction with this tab when RCS temperature (T ) is < 540 F and de-
- c
- creasing. The overcooling tab will provide the operator with guidance in*
- terminating the overcooling event to prevent MSIS and/or SIAS actuation. *
- Th~e reason the " Overcooling" tab is done in. conjunction with this tab is *
- so the operators can continue efforts to restore off-site power while *
- obtaining guidance for terminating the cooldown from the " Overcooling" *
- tab. It should be noted that with a degraded power condition some of
~
- the valves addressed in the " Overcooling" tab may not have power. These *
- valves'may have to be operated manually. Upon completion of the *
* " Overcooling" tab, the operator continues the recovery actions for- *
- degraded power. *'
h
.s - ,
WP84989 SECTION VII - 3.0 PAGE 30
-4
- m. ... x _
~
n? l _
- 4) If the SDBCS is not available, verify that Ij.
the S/G safety valves are opening to control S/G pressure at ~ 1100 psia and RCS-y temperature (T ) at ~ 555'F: c The S/G safety valves should adequately-
; control RCS-temperature but an effort , should be made to establish control with the SDBCS atmospheric dump valves. A stuck open safety valve cannot be isolated and would . result in'an uncontrolled RCS cooldown.
For this reason, extended use of the S/G safety valves should be avoided. l NOTE l i l_ Loop transit time is ~ 5 to 15 minutes on natural' circulation. .Any changes l
=l in' steam. flow will-take at least that long to show up on affected ,l fl-parameters.
l. s , L k <
- WP84989
~ ' SECTION VII 13.0 PAGE 31-g- .
O
_- . . _ . . - - . ~, . . - - cf 3 STEP 5: Verify adequate core heat removal: U By verifying RCS natural circulation flow and RCS ma'rgin to saturation 2 30'F (subcooled fluid) the operator ensures decay heat is being removed. A) The operator should be'esle to verify natural circulation cooling in progress within 5 to 15 > minutes of losing the RCPs. Natural circulation may be verified by the following indications.
- 1) Hot leg tem'peratures TH* " ** **
and may slowly decrease. This indicates
} that the AT has increased enough to establish the required flow to remove the decay heat being produced.
- 2) Cold leg temperatures (Tc ) should stabilic.e and may s' lowly decrease. This indicates that the AT has increased'enough to establich the required flow to remove the decay heat being produced.
These indications of THand T care assuming a relatively constant S/G pressure is being maintained. l(
,WP84989 SECTION VII - 3.0 PAGE 32 W
_.ev..--v- ,-e,e.,-e ,,---,,-em-., ~.--,.m--,- --nw,--
.,..- 3) RCS AT (TH ~
should be less than 50'F. c Actual testing and experience have shown that a AT > 50'F is abnormal and may indicate that natural circulation flow rate is degraded.
- 4) No abnormal difference between core exit
, thermocouples and hot leg temperatures should exist. If core exit thermocouple temperatures increase much above T '
H natural circulation flow may be insufficient.
- 5) There should be a continuous demand for EFW flow to maintain constant S/G levels.
- 6) There should be a continuous demand for the operation of the atmospheric dump valve (s) or the S/G safety valves to maintain a constant S/G pressure.
If thegj.;(;Gs are functioning as a heat sink
~, ,- - for the RCS, titefe will be steam flow from /-
at least one Iocction. If steam is released
- from the S/Gs, feedwater must be added to maintain level. ].- 'WP84989~ SECTION VII - 3.0 PAGE 33 e
,s B) Verifying that the RCS margin to saturation is
'N'ab 2 30 F ensures that the reactor coolant is maintained subcooled. Circulating a subcooled fluid is the preferred method of removing core decay heat.
- 1) If RCS margin _ta saturation is < 30*F:
...,7_.-..- , . .
a) Reverify RCS pressure control and RCS inventory control safety functions, steps 2 and 3 of this tab. b) Monitor core exit thermocouple
~x temperatures per Figure 2.
. (%) The RCS margin to saturation is not expected to be below 30*F if the RCS pressure and inventory safety functions are being properly satisfied.' If the margin to saturation is
< 30*F, a reverification of these safety functions should identify the problem and provide the directions necessary to correct it. The CET temperatures.are monitored to ensure the core is remaining covered and is being cooled.
Ng WP84989. SECTION VII - 3.0 PAGE 34 e
f-. : STEP 6: Containment integrity is verified in order to (J' maintain the containment building as a fission product boundary. A) This step directs the operator to verify that the containment building parameters are being maintained within allowable limits.
- 1) Average containment building pressure is verified to be 13 to 16 psia. This value is obtained by averaging the four safety channel containment pressure indications on 2C33 (2PI-5601-1, 2PI-5602-2, 2PI-5603-3 and 2PI-5604-4). Verifying containment building pressure normal ensures that there
.- is no large release of high energy fluid in progress inside containment.'
- 2) Containment building temperature is verified to be s 140'F.
~
This value can'be obtained from 2TI-5663 or 2TI-5664 on 2C33 or T-5605-5 or T-5606-6 on the plant or' CAPS computer. Verifying containment-building. temperature normal ensures that there is no large release of high energy , fluid in progress inside containment. i f WP84989 SECTION VII - 3.0 PAGE 35 6
,e,,- , ew w-2..--.-g y-+,e--w-y
- 3) The trend recorders for containment
( i.\ pressure, temperature and humidity are monitored for abnormal trends. These recorders are 2PR-5601-1, 2TR-5660 and 2MR-5660 on 2C33. The outputs of these , recorders may provide the operator with indication of a medium to small primary or secondary-fluid-leak inside: containment. B) .-This step provides guidance to the operator in the event that containment building parameters are abnormal.
~
7- ~
. 1) The RCS pressure control and RCS inventory control safety functions are to be re-verified.
9" These safety functions are Steps 2 and 3 of this tab. This re-verification is an attempt to locate the cause of the abnormal contain-ment conditions.
- 2) This step verifies that the containment building cooling fans, 2VSF-1A/1B/1C/1D, are operating and directs' the operatorL to align SW to their cooling coils if necessary.
e E !' ,. f WP84989 SECTION VII - 3.0 PAGE 36 4
- -* .~ . . .,. .w. , , . , , --,n . . . ,,.,---.----rw -n --.n.,n~~.-n--,.r-,- ---, , , , , - -- . - . ~ . , - ,r we - * .ee-- + e.v-w--,
. , ~( . STEP 7: This step directs the operator to isolate the CCW
() . supply to the containment building by closing 2CV-5236-1 on 2C17. This action is taken because the next steps are going to attempt to re-energize buses. The CCW system may restart when the buses are energized. The CCW supply to containment should be shut to prevent thermally shocking the RCP seals by the sudden restoration of cooling water flow. A rapid cooldown of the RCP seals may cause failure of seal components and excessive seal leakage. The CCW supply to containment, 2CV-5236-1, was chosen in an effort to prevent isolating CCW in containment with a return MOV and the supply check valve. This should (~S prevent possible lifting of CCW reliefs due to
.q) thermal expansion. If 2CV-5236-1 is not available, either return MOV may be used.
GO TO STATEMENT *
- This statement directs the operator to Step 12 of this tab if off-site *
- power is not available to energize 2A1 or 2A2. The criteria of < 19.5 KV *
- on SU #3 or < 141.5 KV on SU #2 are based on the reset value of the 2B5 *
.
- and 2B6 UV relays. If the primery voltages on these transformers are *
- greater than or equal to these. values, the 2B5 and 2F6 UV relays should *
- not be tripped. *
.p -
, . ] WP84989 SECTION VII - 3.0 . PAGE 37 e
\,_)
CAUTION STATEMENT .
. THIS STATEMENT WARNS THE OPERATOR OF THE FACT THAT IF A BUS . . LOCKOUT RELAY IS TRIPPED, THE CAUSE SHOULD BE DETERMINED AND . . CORRECTED BEFORE RE-ENERGIZING THE BUS. .
STEP 8: Attempt to re-energize buses 2A1, 2A2, 2H1 and 2H2 from an.available;startup tradsformert. (SU #3 preferred, SU #2 backup). A) Turn on the synchronizing switch for the bus feeder breaker to be. closed. B) Attempt to close the startup transformer. feeder {} breakers to 2A1, 2A2, 2H1 and 2H2. Performance of this step should restore normal power to 2A1, 2A2, 2H1 and 2H2 from a startup transformer. Since SU #3 does not have the load restriction problem that SU #2 has, SU #3 is considered to be the preferred source of off-site power. If SU #3 is unavailable and the buses are re-energized from SU #2, close attention should be given to SU #2 loading to prevent exceeding its limits. The loading
.o . k _)
WP84989 SECTION VII - 3.0 PAGE 38 6
.n-,
- - . . _- _ . . , .-- . . - ._ - ._= .- - , . ,
4
/~N of SU #2 should be coordinated with the Unit 1 'U control room when both Unit I and Unit 2 are relying on it for power. The rating of SU #2 is 45 NVA with forced air and forced oil cooling. If the fans and l' oil pumps are not available the rating is reduced to 27 NVA. The NVA load on the transformer is calculated as-follows:
MVA = KV x A x f x 10 3 KV = high side voltage from Unit 1 meter A - = SU #2 current from Unit 1 meter
/3 = 1.73 10 3 = 1 x 10 3 (This converts KVA to MVA.)
Additionally, the voltage on all buses should be
~
monitored and a degraded voltage condition avoided by 4 h) minimizing' loading if necessary.
*- GO TO STATEMENT *~
- This statement directs the operator to Step 12 if Step 8 was not successful-*
- atLre-energizing the buses. If the' buses were re-energized, the operator
( *' continues to Step 9.-
- f r,
f\
\.) . WP84989 SECTION VII - 3.0 PAGE 39 o
e k
73 STEP 9: After buses 2A1, 2A2, 2H1 and 2H2 have been
- !J ; ~
re-energized from a startup transformer, the following systems are restored as required. A) Place the Loop II CCW system in service as
'follows:
- 1) Restart a condensate transfer pump, 2P-9A or 2P-9B, for CCW expansion tank makeup.
l-
- 2) Verify a CCW pump is running to provide flow through Loop II CCW.
- 3) Verify SW is aligned for CCW heat exchanger cooling.
- 4) Monitor Loop II CCW expansion tank level.
,~. ~
t CCW is restored to provide cooling for the RCPs, letdown heat exchanger and instrument air compressors.
,, B) Restart an instrument air compressor and place the instrument air system in service:
Instrument air is restored to allow operation of various control valves such as the SDBCS valves. WP84989 SECTION VII - 3.0 PAGE 40 O
7 sf - C)' Restore CCW flow to the RCPs as follows:
^ \-
- 1) Close CCW containment return header isolation valve 2CCW-150.
CAUTION STATEMENT *
. THE RCP SEALS SHOULD BE COOLED SLOWLY TO PREVENT DAMAGE TO THE . . SEALS. .
- 2) Open CCW containment supply valve, 2CV-5236-1, on 2C17.
- 3) Slowly open 2CCW-150 to establish a small amount of CCW flow to the RCP seals.
~) 4) Monitor RCP controlled bleed-off and lower seal temperatures to establish a slow cooldown rate.
- 5) When the RCP seal temperatures have stabilized, fully open 2CCW-150.
a WP84989 SECTION VII - 3.0 PAGE 41 m L
Y (
- D) Restart at least one RCP in each loop if the following conditions are satisfied.
T
- 1) RCP restart criteria'are satisfied per Appendix H Appendix H criteria should ensure all -
-conditions required for RCP operation are satisfied.
- 2) S/U transformer load capacity is available:
1 This step addresses both transformer load e'
.. &j capacity and system voltage considerations.
a) Each RCP represents ~ 5 HVA of additional load: J This information is provided to allow the operator to evaluate the present
- load on a S/U transformer and ensure it will not be overloaded when a RCP is running in addition to the present load, a
WP84989 SECTION VII - 3.0 PAGE 42 e m
,. - , - . . ,, . - - , , . _ . . ~,yw ..y -. v .---p-..g,r- !,,-. - - - -p._ ,ow,., , e--,-7 ,w,e%,- ,-.m--,,.c ,w,--,.9,y y _.v.-c
-q b) If both units are on S/U 2, coordinate
- ff 6 with Unit I to ensure S/U 2 MVA limits are not exceeded:
45 MVA with forced air and forced oil cooling: 36 MVA with forced air cooling: 27 MVA without forced air cooling: The only time transformer overloading is expected to be a problem is when y , /~4) both units are on S/U 2. The only
%)
time S/U 3 loading could be a problem is if no forced air and forced oil cooling can be established. c)- If it appears that with additional transformer loading the steady state 4160 V bus voltage will decrease below
~ 3800 V, no more loads should be started until voltage conditions improve:
WP84989 SECTION VII - 3.0 PAGE 43 e
C
.o .,3 LIf at least 3800 V are maintained on the 4160 V buses, 2A3 and 2A4 should be able to be supplied by off-site power. This voltage is above the reset value for the 2BS/2B6 UV relays. This step is a reminder to monitor system voltage while placing additional loads;on'.the. electrical system. If off-site power supply.
lines are limited or voltage is abnormally low, the operator may not Want to start many large loads to prevent further system degradation. . d) The following table of thumb rules may be helpful in determining transformer ' loadings-I INPUT l 45 MVA l AMPS PER l AMPS PER l. AMPS PER l s l VOLTAGE l AMP LIMIT l RCP l CW PUMP l COND. PUMP l t- ! . I i 1 I 7, l 161 KV l 161 A l 18 A l 21 A l 11 A l 1_ l I I I I l 141.5 KV1 184 A l 20 A l 23 A l 13 A l
- i.
D WP84989 SECTION VII - 3.0 PAGE 44 6 -
r o
,, This table lists the number of amps i that correspond t'o the 45 HVA load limit for two voltage conditions.s,,
N: A .< Data is given for the 161 KV condition e since this is the normal supply voltage to S/U 2. Datacis given*for the 141.5 KV condition since this is
-+
the lowest voltage that will allow the use of S/U 2. The amp limit is given for the 45 MVA condition because it is very likely that forced air and forced oil cooling will be available. The
,~ . amp values given for the RCPs, CW \~
pumps and condensate pumps are approximate values that_one of these pumps running will increase S/U 2 amperage by.
~
RCPs are restarted to provide forced flow [ circulation to remove core decay heat. If S/U 3 is available'with normal system voltage, all 4 RCPs may be restarted to help maintain Hot Standby conditions.
^T (G
WP84989 SECTION VII - 3.0 PAGE 45
.s i ** } % e
s.
-J; e ,__, IE) Monitor RCP seals for proper operation:
1 A_/ WN# RCP seal operation,is monitored because the seals may have exp'erienced a large thermal. transient.~ This thermal transient or just the fact.that the RCP lost power and stopped may Or ? ? have caused a seal failure. o; f
, F) If possible, place the letdown system in service:
s. t The letdown system is placed in service to allow E automatic control of pressurizer level. fc- .
~ STEP 10: Restore Secondary Systems to normal operation as A, _'
follows: A) Place the circulating Water System in operation per OP 2104.03. B) 1 Place the condenser vacuum System'in service and
- ( 'l '
establish condenser vacuum per.0P 2106.10.
- t .C) Place the Feedwater and Condensate System in service on short path recirculation through a demineralizer per OP'2106.16.
Q_
' k ,. ,[ D) Establish steam flow through the SDBCS turbine bypass valve (s) to the. condenser for RCS temperature control and close atmospheric dump valves.
t . 1 WP84989 SECTION VII - 3.0 PAGE 46 6 e
i i 1
.1,_3 E) IF desired, shift EFW pump suction to demineralizer outlet.
The above steps should re-establish the main condenser as the heat sink for the secondary. This is desired so that secondary inventory can be maintained. CAUTION STATEMENT *
=* THIS STATEMENT CAUTIONS THE OPERATOR THAT TRANSFERRING 2A3 AND 2A4 . . TO A STARTUP TRANSFORMER WITH A DEGRADED VOLTAGE CONDITION OR A . . LOW AVAILABLE LOAD CAPACITY (i.e., BOTH UNITS ON SU #2) MAY CAUSE . '. 2A3/2A4 TO TRANSFER BACK TO THE EDGs IF A LARGE LOAD IS STARTED. . THIS.WOULD HAPPEN IF THE U/V RELAYS ON 2A3/2A4 OR 2B5/2B6 ARE s-
- ACTUATED.
THIS CONDITION SHOULD BE PREVENTED BECAUSE ON A U/V
.(m ) .
- CONDITION ANY RUNNING ESF PUMPS POWERED FROM 2A3/2A4 ARE LOAD .
- SHEDDED. THE EDGs WILL HAVE TO RE-ENERGIZE 2A3/2A4 BEFORE THE .
. REQUIRED ESF PUMPS CAN SEQUENCE.BACK ON OR BE~MANtfALLY RESTARTED.
- STEP 11: Transfer 4160 volt ESF buses 2A3 and 2A4 from the EDGs to 2A1 and 2A2 as follows:
A) Verify available. load capacity and normal voltage on the-startup transformer powering 2A1 and 2A2. e~x-WP84989 SECTION VII - 3.0 PAGE 47 e
, ~.~,
aI(
,q .j ; B) Verify normal voltage on 4160 volt non-ESF buses -Li 2A1 and 2A2. /< C) Synchronize the 4160 volt ESF buses 2A3 and 2A4 with their normal supply buses, 2A1 and 2A2, and .W close the normal feeder breakers, 2A309 and 2A409.
D) ' Shutdown the EDGs per OP 2104.36, Section 10.0 This step establishes the normal electrical lineup
, for power to 2A3 and 2A4. This lineup is desired because it establishes the EDGs as backup power supplies for off-site power. This step should not be O
i(T V performed unless ~ 22 KV or ~ 161 KV is present on ' the supply to the S/U transformer and ~ 4160 V is O present on 2A1 and 2A2.
-***************************e**************************************************
$k ;f. '*- :9 s GO TO STATEMENT *
'* This statement directs the o;serator to Step 8 of the " Reactor' Trip *
- Recovery". tab now that normal eldctrical power has been restored to all *
- buses.
- t.
at . f . tM L) WP84989 / / ' SECTION VII - 3.0 PAGE'48 1 IW + 5 . - - ,p-.--, - 3., ,, . m.,,,
,. ..... ....e ............e......e.................................e.....
V' . CAUTION STATEMENT .
. THIS STATEMENT WARNS THE OPERATOR OF THE FACT THAT IF A BUS . . LOCKOUT RELAY IS TRIPPED, THE CAUSE SHOULD BE DETERMINED AND . . CORRECTED BEFORE RE-ENERGIZING THE BUS. .
STEP 12: Energize 2A1 from 2A3 or 2A2 from 2A4: The goal of this action is to provide the power necessary to re-establish CCW cooling to the RCP seals and to restore the Instrument Air System to operation. CCW cooling to the RCP seals is very
'~^{ desirable to help insure seal integrity. The- ~>
Instrument Air System is placed in service to allow operation of various control valves. Energizing 2A1 from 2A3 is listed first because it is the preferred bus to be re-energized. This is due to the Condensate Transfer Pumps (2P-9A and 2P-9B). receiving power.from 2B12. .These pumps may be necessary to provide makeup to the CCW system. h (_) ' I-
'WP84989 SECTION VII - 3.0 PAGE 49 O
(
'-) .
CAUTION STATEMENT *
. THIS CAUTION WARNS THE OPERATOR NOT TO BACKFEED POWER FROM 2A3/2A4 . . TO 2A1/2A2 IF ONLY ONE EDG IS OPERATING PROPERLY. ONE EDG HUST . . REMAIN SUPPLYING ONLY ITS 4160 VOLT ESF BUS. THIS IS TO MAINTAIN . . AN INDEPENDENT ESF BUS, BEING SUPPLIED BY ITS EDG, TO PROVIDE . . POWER TO ONE TRAIN OF ESF EQUIPMENT. .
GO TO STATEMENT *
.This statement directs the operator to step 14 of this tab if only one EDG
- is operating properly and the other EDG will not be able to be returned to *
-)
x! service. This will result in 2A1/2A2 remaining de-energized and the plant
- being operated as directed by plant management.
- Prior to energizing 2A1 or 2A2, the buses must be stripped of unwanted loads to prevent possibly over-loading the EDG. The 4160 volt breaker handswitches will be placed in " pull-to-lock" to open the breaker and prevent it from reshutting inadvertently.
t WP84989 SECTION VII - 3.0 PAGE 50 e T- - g- * - . --.-.-- , _- - - - - - .
.-, A) Strip 2A1, 2B1, 2B7 and 2B12 as follows: , -)
- 1) On 2C-10, place the following breaker handswitches in " pull-to-lock" and verify the breakers open.
a) 152-111 SU #2 to 2A1 b) 152-112 Unit Aux. to 2A1
~' ~ c) 152-113 SU #3 to 2A1 152-103- 2A1 to 2B3 d) e) 152-109 2A1 to 2B9
- 2) On 2C-02, place the following handswitches D
in " pull-to-lock" and verify the breakers 1 open. a) 2HS-0609 "A" condensate pump (2P-2A) y);
/-~
b) 2HS-0614 "C" condensate pump (2P-2C) c) 2HS-0730 "A" heater drain pump (2P-8A)
- 3) On 2C-22, place the following handswitch in
" pull-to-lock" and verify the breaker open.
1 a) 2HS-3810 "A" main chiller'2VCH-1A
.The above steps are designed to allow the stripping of 2A1 from the control room. This eases operation and maintains remote control of the above equipment.
WP84989 , SECTION VII - 3.0 PAGE 51
c,
'r' , ,u s 4) At 2B1, open all breakers except the - m) following:
a)- 52-112 2A1 to 2B1 b) 52-114 2B1 to 2B12 c). 52-133 2B1 to "A" instrument air compressor (2C-27A)
- 5) At 2B7, open'all breakers except the following:
a) 52-712 2A1 to 2B7 b) 52-721 2B7 to "C" CCW pump (2P-33C)
- 6) At 2B12 open all breakers except,the following:
a)- 12B2 "A" condensate 1 transfer pump (2P-9A) h)-~ -
.. b). 12D5 "B" condensa e transfer pump (2P-9B)
The above steps are performed locally; however, operation of the equipment controlled from the control room should not be affected.
- p 'WP84989 SECTION VII - 3.0 ~
i. PAGE 52 e
w,- F
-s OR -I, .
B)- Strip 2A2 and 2B2 as follows:
- 1) - On 2C-10,' place the following' breaker handswitches in " pull-to-lock" and verify the breakers open.
a) 152-211 SU #2 to 2A2 b) 152-212 Unit Aux. to'2A2 - 6)' - 152-213 SU #3 to 2A2 d) 152-203 2A2 to 2B4
- e) 152-204 2A2 to 2B8 f) 152-209 2A2 to 2B10
- 2) on 2C-02, place the following handswitches in " pull-to-lock" and verify the breakers open.
a) .2HS-0620 "B" condensate pump (2P-2B) b) 2HS-0626 "D" condensate pump (2P-2D) c) 2HS-0722 "B" heater drain pump (2P 8B) -
- 3) On 2C-22, place the following handswitch in
" pull-to-lock" and verify the breaker open.
a). 2HS-3812 "B" main chiller (2VCH-1B). The above steps are designed to allow the
. stripping of 2A2 from the control room. This eases operation and maintains' remote control of-the above equipment.
5,(')? WP84989' .SECTION VII - 3.0 PAGE 53 O w w - g -wwa-* , ggay- -ye y- -* gm-aep-'- ,-%-=~ +g ,,-e- , w y-g+-,, # m -mgv- w .-, -yey- , e- g we- ag gr-m-,w-,y 9.+-per-*-e+-Trw- + M7
At 2B2 open all breakers except the 3 4)
,._ ,1 .
following: __. a) 52-212- 2A2 to 2B2 b) 52-223 "B" CCW pump (2P-33B)- c) 52-233 "B" instrument air compressor (2C278) The above steps are performed locally; however, operation of the equipment controlled from the control room should not be affected.
. CAUTION E 'ATEMENT - . . THIS CAUTION ALERTS THE OPERATOR TO MONITOR THE LOADING OF THE EDG . . AS THE BREAKER, 2A309/2A409, IS CLOSED TO ENERGIZE 2A1/2A2. IF THE . - (~} - . LOAD EXCEEDS 2850 KW, THE BREAKER SHOULD BE TRIPPED AND THE CAUSE .-
r
'\,,) . OF THE EXCESS' LOAD DETERMINED AND CORRECTED PRIOR TO RE-ENERGIZING . .:THE' BUS. .
C) Energize 2A1 from 2A3 by closing 2A309 or
-energize 2A2 from.2A4 by closing 2A409. Closing.
2A309 will energize 2A1, 2B1, 2B7 and 2B12. This will provide power to a CCW pump, an instrument air compressor and two condensate transfer pumps. Closing 2A409 will energize 2A2 and 2B2. -This will provide power to a CCW pump and an instrument air compressor. WP84989 SECTION VII - 3.0 PAGE 54
ee.....................................................................
'~~
- CAUTION STATEMENT .
. THIS CAUTION WARNS THE OPERATOR OF THE FACT THAT THE EDG SUPPLYING . .-2A1 OR 2A2 IS NOW SUPPLYING'NON-VITAL EQUIPMENT. EXTREME CARE MUST . ,- . BE TAKEN TO PROTECT THE ESF BUSES IN THIS CONDITION. BUSES ARE NOW .
A
. ENERGIZED THAT HAVE LOADS FAR IN EXCESS OF THE EDG CAPACITY. IF . . THESE LOADS WERE TO BE STARTED, AN UNDERVOLTAGE OR OVERLOAD e.
- CONDITION COULD OCCUR. 'AN UNDERVOLTAGE CONDITION ON THE'ESF BUSES .
. WILL TRIP BREAKER 2A309/2A409 TO SHED THE EXCESS LOAD. A SEVERE . . OVERLOAD COULD RESULT IN THE OPENING OF 2A308/2A408 RESULTING IN .
- THE LOSS OF 2A3/2A4. .
STEP 13: Restart Loop II CCW and the Instrument Air System.
.r~y A) Loop II CCW is restarted to provide cooling .L.) _
water to the RCP seals and the Instrument Air i compressors. It is placed in service as follows:
- 1) Verify that a CCW pump is running (2P-33C or 2P-33B) and is aligned to provide flow through Loop II CCW. Only one CCW pump
< will be available, 2P-33C if 2A1 was energized and 2P-33B if 2A2 was energized.
If the available pump was supplying Loop II when power was lost, it should restart when 2A1 or 2A2 is re-energized. ['y v WP84989 SECTION VII - 3.0 PAGE 55
~o h - - . d v. p u g,- , , . _ ,,-,p , gm.t y.------+wy 4- --m - - , - - - - - ,. - - w
,s; - 2) Festart a Condensate Transfer Pump (2P-9A ; i-or 2P-9B) if 2B12 is energized. This will-provide makeup to the CCW system, if required.
- 3) Verify SW is aligned for CCW heat _ exchanger cooling
- 4) Monitor Loop II CCW expansion tank level.
B) Restart an Instrument Air Compressor and place the Instrument Air System in service. This is performed'to enable operation of various air operated valves. C) Restore CCW flow to the RCPs as follows:
- 1) Close CCW containment return header isolation valve, 2CCW-150. This will allow (s opening of 2CV-5236-1 without initiating
\--)-
flow to the RCPs. CAUTION STATEMENT . THIS CAUTION WARNS THE OPERATOR THAT THE RCP SEALS SHOULD BE COOLED .
-SLOWLY TO PREVENT DAMAGE TO THE SEALS. .
- 2) Open CCW containment supply valve, 2CV-5236-1 on 2C17. This will line up CCW to the RCPs with the exception of 2CCW-150.
- 3) Slowly open 2CCW-150 to establish a small amount of CCW flow to the RCP seals.
fd v t WP84989~ SECTION VII - 3.0 PAGE 56 e
;, 3. - 4) ' Monitor RCP controlled bleed-off and lower . ('~)~
Escal temperatures to establish a slow cooldown rate.
- 5) When the RCP seal temperatures have
. stabilized, fully open 2CCW-150. This will restore full CCW flow to the RCPs.
STEP 14: ' Operational concerns when off-site power will be unavailable for an extended period of time. A) .A natural circulation cooldown per OP 2203.13 may need to be performed based on the decision of plant management. B) Condensate inventory should be verified to be sufficient to maintain Hot Standby conditions or
~
to accomplish a cooldown. Based on data obtained from CE-NPSD-154, Natural Circulation Cooldown, an estimate of the amount of condensate required to reach shutdown cooling can be performed. The following estimates of condensate usage may be used:
~ 250 gallons per.*F of cooldown required ~ 12,500 gallons / hour for decay heat removal (1-8 hours after trip) ~ 8,500 gallons / hour for decay heat removal (8-24 hours after trip) ~ 7,000 gallons / hour for decay heat removal
(> 24 hours after trip)
~ . WP84989 SECTION VII - 3.0 PAGE 57 m
La-..
] - #i -fc ;
g . EXAMPLE: R ]' ~
~
The plant is maintained at 545*F for 1 hour, then-the decision is made to perform a cooldown. It takes 3.5 hours to cooldown to 350'F. A 6-hour hold is performed during which temperature is reduced to 275'F and pressure is reduced to 1500 psia... . It takes .5 hour to reduce pressure to
< 700 psia and remove the SITS from service. It then takes I hour to reduce pressure to < 300 psia and place shutdown cooling in service.
Cooldown from 545'F to 275'F
-(545'F - 275'F) (250 gallons /'F) = 67,500 gal, s
Plant maintained at 545'F for 1 hour (12,500 gallons / hour) (1 hour) = 12,500' gal.
/"NJ '3.5 hours to cooldown to 350*F .As-) L (12,500 gallons / hour).(3.5 hours) = 43,750 gal.
6-hour. hold at 1500 psia (12,500' gallons / hour) (3.5 hours) = 43,750 gal. (8,500 gallons / hour) (2.5 hours) = 21,250 gal.
' 5 hour to reduce pressure'and isolate SITS 1c '(8,500 gallons / hour)-(.5 hour)' ~ = 4'250 gal.
I hour to reduce pressure and go on SDC (8,500 gallons / hour).(1 hour) .= 8,500 gal. TOTAL = 201,500 gal.
' The volume of.one CST is 200,000 gal.-
C)- EDG fuel oil inventory should be monitored closely
/
to ensure that an adequate supply. is available for long-term operation of the EDGs. M. 6 LWP84989' -SECTION.VII - 3.0 PAGE 58
'e .
7 .s . D) To limit the load on the station batteries
-( '~~').
and/or their chargers, the following actions should be considered:
- 1) The hydrogen in the main generator can be vented off, and the emergency seal oil pump may be secured. _
2). ,The-main turbine / generator and main
. feedwater pump / turbine. AC powered lube oil cumps may be restarted and the DC lube oil pumps secured. These turbines should also , be placed on their turning gears once they have stopped.
- 3) The inverters should be reset to normal AC j Power.
STEP 15: Place the plant in the operating mode determined by plant management. Maintain the plant in Hot Standby or perform.a natural circulation cooldown as determined by the plant manage-ment. Emphasis should be placed on-the amount of condensate storage tank water needed to cool down the plant. Approximately 200,000 gallons of water will r be.used to perform a natural circulation cooldown, i
/-H > 1 k/
m WP84989 EECTION VII - 3.0 PAGE 59
-___-_________m_________-.___._m- ___________._______.._._m___ _ _ _ - _ _ _ _ _ _ _ _ . _ _ _ _
f f-and approximately 12,500 gallons / hour are needed to remove decay heat for the first 8 hours after a reactor trip. Promptly commencing the cooldown will minimize the amount of CST water required. b e L I 1 J . 4 I-l. i ~ ? i-I s ! 'WP84989. SECTION VII - 3.0 PAGE 60 Ig
7_q 4.0 BLACKOUT RECOVERY ACTIONS t i
~#
,. 4.1 Operational Goals b
.The primary operational goals of the Blackout Recovery Tab are the restoration of a power _ source to supply at least one ESF electrical system and the stabilization of vital plant parameters using equipment powered from that ESF electrical system. The secondary goals are the restoration of a stable off-site power source that allows the plant to be returned to a Hot Standby condition with forced RCS flow.
4.2 Description of Blackout ('*j - A Blackout condition is a complete loss of AC power to the plant LJ systems and equipment from the off-site power grid and the main turbine generator in conjunction with a failure of both emergency diesel generators to start or supply power to their associated ESF electrical systems. The absence of electrical power reduces the operator's ability to control the plant due to the loss of all electrical equipment with the exception of vital instrumentation supplied by battery powered inverters, emergency DC lighting, DC control power:for electrical breaker operation and indication, DC powered valves and solenoid valves, and DC powered pumps. Local-manual operation
-.of some equipment and valves may be required.
WP64989' SECTION VII - 4.0 PAGE 1 u
c:: 7g Operator actions during this event are directed at restoring an
<f electrical power source and maintaining the plant in a stable condition until power is restored.. Conservation of RCS inventory and maintaining heat removal capabilities are the most important actions required while attempting to restore electrical power.
With no RCS makeup capability, RCS inventory control will consist of conservation measures such as isolating letdown flow, maintaining temperature near the high end of the temperature band and throttling EFW flow to minimize RCS cooldown. An RCS cooldown should not be attempted until RCS makeup and boration capabilities are restored. Since no reactor coolant pumps vill be available until an ()). Q ' off-site electrical power source is made available, natural circulation flow must be established in the RCS to transfer' O decay heat from the core to the S/Gs. 1 Adequate RCS heat removal is maintained by ensuring that the S/Gs are available as a heat sink. Emergency feedvater (EFW) to the S/Gs is supplied by the steam driven EFW pump (2P-7A) from the. condensate storage tank. Heat removal from the S/Gs must be accomplished by local-manual operation of SDBCS atmospheric
- dump valves or the main steam line safety valves because the main condenser is unavailable.
p v
'WP84989 SECTION VII - 4.0 PAGE 2
-a ; g, Maximum efforts should be directed at restoring an electrical. ' k) . power source. If the restoration of electrical power is to be delayed for an extended period of time,-actions should be l
initiated to provide emergency RCS makeup capabilities to
^
assist in the control of RCS inventory. ' ~ 4.3 Safety Functions Affected t
-Vital electrical power, RCS pressure control and RCS inventory control are the three safety functions most directly affected .by a blackout situation. Vital electrical power is aosent-during the blackout transient. RCS inventory control becomes a function of RCS heat removal and primary system component-integrity. RCS pressure control becomes closely tied to RCS - (} '
I V , inventory control. All other' safety functions are not directly affected due to support system availability or inherent design features not' requiring electrical power'for meeting success criteria. Long-term safety function control requires expeditious ' restoration of an electrical power source. t L 4.4 'Hajor Parameter Response ( , I A) Reactor Power Reactor power will respond as during-any reactor trip. Assuming all CEAs are inserted into the core, sufficient
- i. '
' r shutdown margin, as required by Technical Specifications, is available to ensure a shutdown reactor. The absence of p ()~ ' RCS boron injection capabilities does not present an i t WP84989 SECTION VII - 4.0 PAGE 3 m.
D_
. - . a 4
v. 9 1is c knmediate threat to the reactivity control safety function:
; v 1.~ -however,'an RCS cooldown should not be attempted until . boration capabilities are restored. / ~ B) _. RCS Temperature i-In the absence ~of forced RCS flow, RCS temperature will be a function of the: ability of the RCS and S/Gs to remove. (
heat from the core by Natural Circulation (NC) flow. NC flow is governed by the amount of decay heat, component. . elevations, primary to secondary heat transfer, loop flow. resistance, and the amount of voiding in the RCS. RCS average temperature (T,y,) will initially decrease due to'the reactor trip. After the trip, hot leg (T ) and H cold leg (Tg) temperatures will increase slowly.until TC-reaches the saturation temperature which corresponds to the lowest S/G safety valves pressure setpoint. The T H temperature will. continue to' rise slowly until sufficient , t temperaturedifferential'(AT)fisestablishe'dtoprovide the required driving head for NC. flow through the RCS.. l Steam generator' safety valves should control saturation-
, pressure in the S/Gs and stabilize RC3 temperatures.
Local-manual operation-of the SDBCS atmospheric dump u valves may be used to control S/G pressure and RCS temperature and minimize the possibility of a steam safety
- valve failure. If atmospheric dump valves are used, S/G h
()' pressure should be controlled slightly lower than' safety WP84989 SECTION VII - 4.0 PAGE 4 .; 4 L, .- , _ . _ _ . _ _ _ _ _ _ _ _ . . _ _ _ . _ . . _ _ ____.___._._..___..._____._____._______.____________._______.__m
R - - c ., e l
-s c -
j.,7 . "N; .X
, ?.
U
<~s . , l valve.setpoint to; maintain an elevated RCS temperature and k); , ' . maximize available RCS inventory.
C) Pressurizer Pressure and Level O ' s With no contro1' systems available for pressurizer pressure "or' level control,-these parameters become interrelated and ' ~ l
>' are influenced and controlled by RCS temperature. Pressurizer . l i-pressure, without heaters and spray, becomes dependent on the i
pressurizer's' ability to " squeeze" or " expand" the steam bubble with1 level changes thereby increasing or decreasing pressure.
+
i g , Without charging pumps, pressurizer level control becomes i. a function of RCS density which is controlled by RCS ' temperature. Letdown system flow should be isolated for
)
u inventory conservation. I t. _ Sufficient pressurizer pressure and level should be , I 6 ' ' available at the onset of this transient to provide the operator;with a starting point of sufficient volume-in the pressurizer to allow for controllability of the situation.'
.l Long-term control of the RCS pressure and inventory safety functions will require restoration of electrical power or provisions for emergency makeup. RCS inventory will decrease at a rate of ~ 4 gallons per minute due to the inability to isolate RCP control bleed-off flow. ( ~
[fy x_- .
, I WP84989 SECTION VII - 4.0 PAGE 5 i
4 4 1
-_---s
f j3 - f D) , Steam Generator Pressure x) Steam generator pressure will initially increase due to
- the termination of steam flow to the main turbine. S/G pressure will be controlled at the setpoint of the S/G '
safety valves. Local-manual operation of-the SDBCS. I atmospheric dump valves may be used to control S/G- ' l
~
pressure.slightly below the setpoint of the safety valves. Local-manual control of these valves will be 4 required ~because of the loss of power to the. SDBCS control panel and the possible loss of instrument air. 1 E) Steam Generator Level Steam generator level will initially decrease rapidly n following the reactor-turbine trip due to " shrink." If ' s.(} S/G levels decrease to < 46.7%, the Emergency Feedwater .
%.j (EFW) System will be actuated and will be available to -
restore S/G levels. The steam driven EFW pump (2P-7A) f; will start immediately.and supply EFW to the S/Gs from the ; I condensate storage tank.
,yr i
Af ter verification of proper EFW system operation, manual control of EFW components may be required to prevent excessive S/G feeding which can result in RCS temperatures . 4 being reduced below the desired value. This decrease in RCS temperature would cause a decrease in pressurizer pressure and level. Maintaining S/G 1evels above the I
;g !y)
WP84989 SECTION VII - 4.0 PAGE 6 f
r:
,_s minimum required level (~ 30% wide range) for adequate '( l '~' ' heat transfer is essential to maintain natural circulation flow in the RCS.
4.5 Bases for Blackout Recovery Actions STEP 1: Attempt to energize the 4160 volt ESF bus (es) 2A3 AND/OR 2A4 with the Emergency Diesel Generators (EDGs): Energizing ESF buses restores safety-related systems and restores instrumentation commonly used for monitoring the status of other safety functions. Also, energizing ESF bus (es) restores the ability to maintain the RCS inventory and RCS pressure control safety functions. With'no cooldown, these safety functions should initially r3 be satisfactorily maintained, but with loss of inventory V due to RCP controlled bleed-off and no RCS makeup available these safety functions are degrading. CAUTION . . IF AN EDG HAS AUT0 ' STARTED BUT FAILED TO ENERGIZE ITS ASSOCIATED *
. BUS, SERVICE WATER WILL NOT BE AVAILABLE, 50 EDG TEMPERATURES MUST * . BE CLOSELY MONITORED. IF THE BUS (ES) WILL BE UNAVAILABLE FOR MORE
- 1* THAN A SHORT PERIOD OF TIME, THE EDG(S) SHOULD BE SECURED. THE
- HIGH TEMPERATURE ALARMS ON THE EDG PANELS MAY BE USED AS GUIDANCE
- ON WHEN A POSSIBLE OVERHEATING CONDITION EXISTS. *
/ h .)
WP84989 SECTION VII - 4.0 PAGE 7
l .
,- A) If EDG(s) are running and the EDG(s) output
( J breaker (s) 2A308/2A408.did not closer If the EDG(s) have autostarted but the output i-breaker (s) did not auto close on bus low voltage, the I problem is in the interlocks associated with the auto l close circuitry. The following interlocks could prevent 2A308/2A408 from closing.
- 2A3/2A4 bus lockout - EDG not at rated speed (> 810 RPM or ~ 54 h:)
1
- EDG not at rated voltage - 2A3/2A4 cross tie breaker (s) (2A310/2A410) shut - 2A3/2A4 normal feeder breaker (s) (2A309/2A409) shut ' ~ '~] - EDG ou;put breaker (2A308/2A408) handswitch in " pull-to-lock" on 2C33 i ?
- 1) Verify 2A3/2A4 normal feeder breaker (s) ,
t 2A309/2A409 are open on 2C33: l-Breaker (s) 2A309/2A409 should open on an l undervoltage trip. If the breaker (s) did not open, they must be opened, prior to manually shutting the EDG output breaker (s), to prevent the EDG(s) from being overloaded by trying to energize the non-vital buses. Opening breaker (s) 2A390/2A409 may allow the EDG(s) I output breaker (s) 2A308/2A408 to auto close. WP84989 SECTIO!! VII - 4.0 PAGE 8 4
m-i
.f g .
2); -VerifyL2A3/2A4 cross tie breaker (s) 2A310/2A410' d - are open on 2C33: Breaker (s) 2A310/2A410 should open on an i undervoltage trip. If the breakers did not open, l they must be opened to ensure that 2A3 and 2A4 l are independent so that a single fault will not endanger both buses. Opening breaker (s) 2A310/2A410 may allow the EDG(s) output breaker (s) 2A308/2A408 to auto close. I
- 3) Verify EDG(s) at 60~HZ AND 4160V on 2C33:
B 6 e Verifying that the EDG(s) are at 60 hz AND 4160V
.('{L
(_f ensures that degraded speed or voltage l-conditions are not present which would prevent l
't auto closing of the EDG(s) output breakers .
I (2A308 and/or 2A408). If the EDG(s) are not
'> 310 rpm (~ 54 hz) or if.the EDG(s) are not at rated voltage (~ 4160V), the output _ breakers l will not auto close. Adjusting frequency and/or ~!
voltage may allow the EDG(s) output breakers to
- 3. auto close.
( o WP84989 .SECTION VII - 4.0 PAGE 9 i u _ _ _ _ _ _ _ _ _ ________ _ _ _________ _ _______.__ ___ _
j_ 4)- ' Verify.2A3/2A4 bus lockout alarm (s) are not F
>~' presenti a) .2K08 J-4 (4.16 KV bus 2A3 lockout relay failure)
I
. b) 2K09 J-3 (4.16 KV bus 2A4 lockout relay j
- i. failure)
If the lockout relay failure alarm (s) are in effect, either DC control power, as sensed at i p; 2A309 or 2A409, has been lost to the 2A3 and/or 2A4 bus (es) or the bus lockout relay has tripped. If the bus lockout relay (s) on 2A309 ' (my and/or 2A409 is (are) tripped, a fault, as
'%) . indicated by phase overcurrent relays, has occurred on bus (es) 2A3 and/or 2A4.
j. Re-energization of a bus, after a bus lockout has , I occurred, should not be attempted until the fault is corrected. ? If the bus lockout' relay (s) on 2A309 and/or 2A409 are not tripped, restoration of DC control power or manual closure of breakers to re-energize the bus can be attempted. If the normal feeder breakers (2A309 and/or 2A409) individual DC control power breaker (s) is [ f} m
~WP84989 SECTION VII - 4.0 PAGE 10 t
1
. . . .. . _~ ._ . . _ . _ _ _ - ~ . _ . ._ ._. . - - _ . ~
w
~,
[ Fu E . , e i l [ .; Ls tripped,-lockout relay failure alarm (s) will be ; k__1 > i
- . in. The major supply of DC control power is b ' -
, provided to bus 2A3 via 2D23 breaker 4 and to
- h. '
bus 2A4 via 2D24 breaker 4. Restoring DC control power may allow the EDG(s) output breakers 2A308/2A408 to auto close. If DC l-
' control power cannot be restored, the manual l closure of breakers will still be possible. If ,
breakers are manually closed and DC control. ' power is not available, the automatic trips li associated with that breaker are . defeated. i,
- 5) Turn synchronizing switch 152-308/152-408 to on: ':
This will allow manual closing of breaker t . 2A308/2A408 from 2C33. 'i 1 il
- 6) Attempt to close EDG(s) output breaker (s) 2A308/2A408-from 2C33: (
If there is no bus lockout on 2A3/2A4'and.the 1 EDG(s) is running, the output breaker should be capable of manual closing from 2C33. . l l A e , _.
'WF64989 SECTION VII - 4.0 PAGE 11' 5t -..xa. , . - . , . . . , . - - _ - - _
,7 3 7) If EDG(s) output breaker (s) cannot be closed and '~' )
a high temperature alarm is received on Jacket Coolant Water or Lube oil, the EDG(s) should be secured i I If the EDG(s) are running and the output breaker l' cannot be shut, the EDG(s) need to be secured before it undergoes mechanical damage. The high , temperature alarms are a guidance to the operator. If operability of the output breaker i may soon be restored, allowing restoration of SW pumps for cooling, then the EDG(s) do not need to be secured. ': r^T
'% ]
B) If the EDG(s) are not running, attempt to start 2DG1/2DG2 and energize their associated ESF bus (es) by one of the following methods: , I-If the EDG(s) fail to start, the failure problem should i be investigated and repaired. The operator should l evaluate the alarms that are present and determine the cause of the EDG(s) failure. I
+ 1 WP84989 SECTIO!! VII - 4.0 PAGE 12 i
y ,..e ?
"i n s 9 3 1) If EDG Not 'Available alarm (s) are not present,
..J attempt to start 2DG1/?DG2 frem 2C33: ,
If the EDG not available alarm (s) is not present and the EDG did not attempt to stect, the EDG(s)> should be able to be started at 2C33 or a local - .i
.t control switch. Without the above alarm in, the start circuitry of the diesel should be intact. ,
This would imply that the EDG(s) is failing to , receive a start signal. The diesel should be - I able to start from 2C33 or locally. Since it should start from either location, the operator s is directed to start from 2C33 for time and ease l of control considerations. -
\m-} _ } ri a) Verify 2A3/2A4 normal feeder breaker .
2A309/2A409 is open: . I Breaker (s) 2A309/2A409 should open on an .! undervoltage trip. If the breaker (s) did-not open, they must be opened prior to , energizing the bus (es) with the EDG(s) to prevent the EDG(s) from being overloaded by trying to energize the non-vital buses. 6 O' V
' WP84989 SECTION VII - 4.0 PAGE 13 01
N 7_ b) Attempt to manually start 2DG1/2DG2 and ^ verify frequency and voltage normal .
-Using the control switch on 2C33 or '
locally, attempt to start.2DG1/2DG2. This should start the.EDG(s)-if the failure of l the EDG(s) to start was caused by the lack of an emergency start signal.
+
c) Turn synchronizing switch 152-308/152-408 l to on: This will allow manual closing of breaker . '
}}
152-308/152-408 from 2C33.
- s /.
l
+
d) Energize 2A3/2A4 by closing EDG output ' breaker 2A308/2A408. (Breaker may close , I automatically when EDG.is started): The EDG(s) output breaker (s) 2A308/2A408 l should have automatically closed when the EDG(s) reached rated speed and voltage. If the breaker (s) did not automatically close, close them manually from 2C33.
~ WP84989 SECTION VII-- 4.0 PAGE 14 i
~ '
,f e) Verify SW pumps and all required ESF loads V
are started: When 2A3/2A4 are energized, the required i-loads should sequence on. It is necessary b to verify a service water pump has started j' and aligned to supply ecoling to the EDG(s) to maintain availability of the EDG(s). . f 12 ) If EDG Not Available alarm (s) are present, reset I the lockouts and attempt to start 2DG1/2DG2 from 2C33 or locally: ("'} The EDG Not Available alarm present when the EDG , V. is not running gives the operator an indication 'j , that there is a problem and that the EDG will not start either automatically or manually from , t 2C33. The conditions that could give you this alarm need to be. identified and corrected to l allow the EDG(s) to start. The conditions that 4 could cause this alarm are
~! - Remote switch on 2C33 (CSI-2DG1/2DG2) in " pull-to-lock" - Local control switch RS1 at 2 Ell /2E21 in " lockout" - 152-308/408' in " pull-to-lock" on 2C33 i
(~3 - ACB-308/408 not racked in i) s WP84989 SECTION VII - 4.0 PAGE 15 ;
<g Wj ' - 2DG1/2DG2 lockout relay tripped d: - Engine Shutdown Relay energized . - Engine speed > 250 RPM - Jacket water pressure > 8 psig i a . ,g l ,,.y. a) Verify overspeed Trip Hechanism at the EDG l 1s-reset The Overspeed Trip mechanism must be reset 0 :t at the EDG if it was tripped. If this trip s ..
1 is- .B is actuated, it must be reset before the Shutdown Relay (SDR) can be reset. 6
,s , b) At EDG local control panel (2E11/2E21) depress SDR reset button:
t i The shutdown relay is energized by either a , I [ >y=: EDG start failure, EDG overspeed or low EDG y lube oil pressure. 'The problem that caused 'l
.w ~
i , y[ , 4. the SDR to be energized should be l investigated, and then reset the SDR using q~.3 i1 ,, !
.; -the pushbutton on 2E11/2E21.
3, l r 3; . .) - s s , s ;.
. Qj; :
m WP84989 , SECTION VII~-,4.0- PAGE 16
~
i ' W, p. c
. ,+-Ni (
- _ Ll_1 4
- c) At bus 2A3/2A4 verify normal feeder breaker O
t 2A309/2A409 is open and bus lockout relays
, are reset:
Breaker (s) 2A309/2A409 should open on an I undervoltage trip. If the breakers did not 'l. 4 open, they must be opened, prior to manually shutting the EDG(s) output breaker (s) to prevent the EDG(s) from being overloaded by trying to energize the I non-vital buses. The 2A3/2A4 bus lockout would not prevent 8 the EDG(s) from starting, but it would . prevent it from tying on the'line. Therefore, if the lockout is tripped, the f problem needs to be investigated and :. l-corrected. The EDG(s) should not be started-until the' problem on the bus has been f corrected and the bus lockout is reset.' l l 1 d) Verify the EDG lockout relay on the EDG output breaker 2A308/2A408 is reset: If the EDG lockout is tripped, (indicated by EDG Lockout Relay Trip Alarm on t-
.}
j
. ;2 WPB4989 SECTION VII - 4.0 PAGE 17 i.
L' ..._t
7-~s '2K08/2K09) the cause of the lockout must be ( identified before the lockout is reset.- If
. the cause of the lockout was due to energizing the SDR, which was reset in a i previous step, there will not be any flags 1
dropped.- But, if the SDR was not the cause l of the lockout, the cause can be determined by looking at the flag indications on 2E11/12 or 2A308/2A408.
'l.
Resetting the EDG lockout should allow the EDG to autostart and auto close the output breaker. ' , . p ' Le) Manually start 2DG1/2DG2 and verify' frequency ~and voltage normal i If the EDG did not auto start,'use.the.- r
'handswitch on 2C33 or locally on 2E11/2E12 ! ~
and start the EDG.' After the EDG is at
] ~-60 HZ and ~ 4160V, the EDG ~ output breaker-2A308/2A408 should auto close.
f) . Turn synchronizing switch 152-308/152-408 to ons-I O; This' will allow closing of. breaker 152-308. A/ WP84989 SECTION VII - 4.0 'PAGE 18 ;
w--
? ,;; , ~ > ??._
e' Z 1
'- ,- .' j v *%1, q,); - . g) . Energize.2A3/2A4'by closing the EDG output i
(Breaker may close
~ . breaker 2A308/2A408. +
n ,
, automatically when EDG is started): i E *t,,- ,~
The EDG(s) output breaker (s) 2A308/2A408 ., li should have automatically closed when the 'll EDG(s) reached rated speed and voltage. If , the breaker (s) did not automatically close, , close them from 2C33 or manually close them- ! at local breaker.
. ll L.
Verify SW pump.and all required ESF loads
. [ h) ' ,y are started:
f
;I n-x When 2A3/2A4 are energized the required, .h loads should sequence on. It is necessary > . :~
to verify a service water pump has started. . t.
?. . , _
and aligned to, supply cooling to the EDG(s) D n-' '
- a.;
'to maintain availability of.the.EDG(s). . T ~
J**'**********************************************************************'******* .
} ~ - * .-4 GO TO ST TEMENT
- Q.. ,
~
- s. ?
- This'; statement directs' the operator to the " Degraded Power Tab" if._one or ; *
;4 y
- ;, a 4s* .both of the EDGs l are made' operable. D *
,ew .< > ?- .. ,' ,f y
- w:-
- ~
xI - ~-' h
- x -
- - +
E ---
-4 9 ./_f__
g 4- . 34 , r , 1 IWP84989c SECTION VII .4.0' PAGE 19~ 4 4 . ' g s sm g )
'.(1 - +, l-\ -- f - ,, , hr,J[e ,4 Z,, , . , , . ,, m/ 4 .+,-...- - ,,; % ...r. ,,,,__-.,,,m_-...--,,--m-_,... .-s-
r
-A. STEP 2: The following actions should be taken to conserve RCS
- (a - 1 inventory and minimize RCS pressure reduction a
Conservation of RCS inventory must be accomplished since there is no capability of making up to the RCS. There-is no power available for isolating the i controlled bleed-off relief valve, therefore there will be - 4 gpm being removed from the RCS with no method of makeup. I A) Isolate RCS letdown by closing 2CV-4823-2 on s panel 2C09: i [ fT Letdown needs to be isolated to conserve RCS V inventory and to prevent overheating of the 'l-letdown system. 2CV-4823-2 is used as the ,
- t. isolation valve because'it.is a D.C. powered- ,
I valve. f STEP 3: Verify adequate RCS heat removal by verifying operation
~ .[
of the EFW system and SDBCS or S/G safety valves: The removal of RCS heat from the RCS is necessary to maintain long term core heat removal. The following steps verify availability of systems required to maintain a S/G as a RCS heat sink. t
.fs: -j ) * .WP84989 SECTION VII -4.0 PAGE 20 f
r - .- Also of concern is a possible overcooling situation d)' due to eveessive RCS heat removal. This is magniEied as,a concern in a blackout situation since there is no RCS makeup available and no RCPs running supplying RCP heat to the RCS. The following steps provide guidance for minimizing possible overcooling l situations while ensuring core heat removal. A) If S/G level (s) decrease below 46.7%, verify actuation of the EFW system: I The Emergency Feedwater Actuation Signal (EFAS) setpoint is 46.7%. If S/G level (s) decrease-
, below this setpoint, th'e operator verifies ,
proper' actuation of the EFW system. The steam driven EFW pump (2P-7A) is the only method of S/G inventory control during Blackout , I conditions. The EFW system will maintain S/G
' levels around .the EFAS setpoint.with no operator- 1 ' action. ,
t;. 9
- 1) Verify EFW pump 2P-7A is running.
'a) Verify proper 2P-7A discharge pressure on 2C16:
l'
.[~N-t .) - WP84989 SECTION VII - 4.0 PAGE 21 1
v
'-~s b) Verify 2P-7A flow on 2C16: . Verifying proper discharge pressure and flow ensures that 2P-7A is supplying water to the S/G(s).
- 2) IF necessary to limit RCS cooldown AND IF S/G levels are being restored, reduce 2P-7A V
speed to limit feeding / steaming rates: i If RCS cooldown is sufficient to cause RCS inventory /RCS pressure control' problems, consideration should be given to minimizing feeding / steaming rates. 2P-7A is (). (,- - t maintained at 100% speed control and would. be providing its maximum feed rates and *- drawing its maximum steam. Reducing speed control on 2C17 for 2P-7A can minimize feeding / steaming. rates.. 4 t B) LIsolate S/G bluwdown by closing 2CV-1016-1 and 2CV-1066-1 on panel 2C17:. s S/G blowdown is isolated to prevent possible overcooling of the RCS and because the system is o no' longer capable of handling it. During (*r u.) ~ WP84989 'SECTION VII - 4.0 PAGE 22 b' b I
t 7 s blackout conditions, the S/G blowdown pumps are if . . de-energized and a vacuum cannot be maintained:
, in the main condenser.
C) Minimize excessive steam demands by securing the
. following steam loads:
To prevent cooldown of the RCS, all unnecessary steam loads need to be isolated. The amount of decay heat (which is dependent on power history) will determine how much time you have to isolate all steam loads before you com-
~)^ )- mence cooling the RCS.
- 1) Secure main steam to the HSR's by closing
'2CV-0400 and 2CV-0460 manually:
f g,. 2CV-0400 and 2CV-0460 need to be manually: shut to prevent a direct steam path from, the main steam header through the MSRs and 2T58s to the main condenser.
~
17 2) . Break vacuum on main condenser: a)' Open' vacuum breakers 2CV-0600 and 2CV-0637 manually. _ (.
.;-N . .
(~~c
.v- .: w.
Ti -- WP84989 , SECTION VII - 4.0 PAGE 23 7
'\ -
c: -
,~,
b) Securing gland sealing steam by p b, s. shutting GS-1 helps. to minimize steam .
. loads. .D) If necessary, close MSIVs from 2C16 and/or 2C17 to maintain RCS temperature (T ) > 545*F:
If cooldown is excessive and RCS pressure, temperature and level are decreasing, shut the MSIVs. This should stop the cooldown and allow RCS temperature to increase to the saturation temperature of the lowest S/G safety valve pressure setpoint. E) Verify RCS heat removal is being accomplished
)
by one of the following methods: Verification of RCS heat removal can be accor-plished by verifying a method to remove the steam, eitherIlocal manual control of the steam dumps or by the operability of the S/G safeties. Since no RCS makeup is available and RCS inventory is being lost from ICB0 by ~ 4 gpm, maintaining.RCS temperature as high as possible is desired. Maintaining RCS temperature as high-as possible'will maintain a pressurizer level as high as possible. n f k'~
- yJ;
'WP84989 SECTION VII - 4.0 PAGE 24
_._ ._.u _
i 4
~Q- 1) Proper operation of S/G safety valves to LJ <
maintain S/G secondary pressure at ~ 1100 . .
#= .. psia: 'S/G' pressure can be satisfactorily main-I, tained by allowing pressure to be maintained j; 'i '
2 at - 1100 psia on the S/G safeties. OR
- 2) Local manual operation of the atmospheric dump' valves (2CV-0301/0305/1001/1005) to 1'
- control S/G pressure at ~ 1050 psig '
a-h Maintaining S/G secondary pressure at 1050 l i- _.
- fG psia with the atmospheric dump (s) will allow . .
A_/:
'p operation below the S/G safety pressure, while at.the same time minimizing the amount of RCS cooldown. . Minimizing the RCS . .! 'l cooldown will minimize the pressurizer:
level!and pressure decrease. _!:
.']-
l 4 c.
- e- , ,
} % b V
- ,~{N-f'S' ,
- WP84989 SECTION VII - 4.0 ' PAGE 25' i 'g"wwwMWt'N7ve-"6"W-]W- ,- ey 9 W-w %"" ? M ?%**' T t-74 'e-**%*7"4>b T w'sW P'Mrpa'*$ppW, P = a yy g g M*M -pw y-y w g g g d=M+vw ayn ew -peg q ' +9T u 9 ety vgo-- + gm v' y1s= p p ww*eWorf,p yrtwe
- - . STEP 4: Verify adequate core heat removal:
A) . Verify natural circulation cooling is established within ~ 5-to 15 minutes: The operator should be able to verify natural circulation cooling in progress within 5 to 15 minutes of losing the RCPs. Natural circulation may be verified by the following indications.
- 1) Hot leg temperatures (T ) should stabilize H
and may slowly decrease. This indicates that the AT has increased enough to (~T establish the required flow to remove the
.<_J decay heat being produced.
- 2) , cold leg temperatures (T ).should stabilize c
and may slowly decrease. This indicates that the AT has increased enou'h g to establish the required flow to remove the decay heat being produced. These indications of TH "" e are assuming a relatively constant S/G pressure is being. maintained. F/~$. Q,) . .
'WP84989 SECTION VII - 4.0 PAGE 26
i + , gf -~ 3) RCS AT (TH ~ c should be less than 50*F. Actual testing and experience have shown
, that a AT > 50*F is abnormal and may indicate that natural circulation flow rate.
is degraded.
- 4) No abnormal difference between core exit
' thermocouples and hot leg temperatures should exist. If core exit thermocouple temperatures increase much above T '
H natural circulation flow may be insufficient.
- 5) There should be a continuous demand for EFW
'{ flow to maintain constant S/G levels.
- 6) .There should be a continuous demand for the operation of the atmospheric dump valve (s) or.the S/G safety valves to maintain a constant S/G pressure.
If the S/Gs are functioning as a heat sink for the RCS, there will be steam flow from at least one location. If steam is released from.the S/Gs, feedwater must be added to
. maintain level.
f-
\,._3 ) - .s.
l 'WP84989 SECTION VII - 4.0 PAGE 27-
7-.s _ STEP 5: Determine the availability of off-site power source:
}u sl The availability of off-site power sources can be determined by checking switchyard status lights on '2C10, by communication with the system dispatcher and - 'by checking the voltage indication on 2C10. The lowest transformer voltage that should be used to energize the. buses is 2 18 KV on S/U #3 or 2 131 KV on S/U #2.
A) Place all handswitches for 2H1, 2H2, 2A1 and 2A2 bus feeder breakers in " pull-to-lock" on 2C10: jd'$ The feeder breakers from the transformers are
'%s placed in " Pull-to-lock" to give the operator positive control of which' transformers are tying' on to the bus.
B)- Check switchyard breaker status'on Panel'2C10 to determine what off-site power sources are available: c) If S/U transformer problems exist, check alarms-
*' ~
on annunciator panel 2K01 to determine possible rf Causes:- i;
-r%.
WP84989- SECTION VII - 4.0 PAGE 28
x j; m . D) If necessary, perform visual inspection of L:V startup transformers, local alarm panels, switchgear, protective relays, and switchyard facilities and attempt to determine and correct
~ any failures:
The operator must use his indications and alarms, to attempt to locate and correct any problems on the transformers. A local inspection of the transformer is done to check the local alarms and reset local lockouts as required.
../~N E)- If failures / problems have been corrected, reset A,f lockouts for S/U #3 and/or S/U #2:
To reset the, lockout on S/U #3 reset ST3-1 and
. ST3-2 on 2C20.
To reset the lockout on S/U #2. reset 186-ST2-1 and 186-ST2-2 on Unit 1 panel .1C20 prior to -
~, ..
resetting 186-ST2-3 on 2C20. This is done
~
L* because,186-ST2-3 will not reset until 186-ST2-1 and 186-ST2-2 are reset. ( i:_D'
~ V . :~
WP84989 SECTION VII - 4.0 PAGE 29
~ $ T W"
s i *
% }
i
.;fi ~
F). If necessary, request system dispatcher to close Q --
< required breakers to restore power to switchyard and/or S/U transformer (s): ~ *: GO TO STATEMENT * /
- This statement directs'the operator to " Step 15" of this tab is off-site *
*(powerfis'unavailableor'if-atleastoneS/Utransformercannotbemade * /' ~" ' *; operable.. There' the operator will maintain hot standby conditions and
- L
- attempt to establish emergency RCS makeup.
- STEP 8: Check SU.#3 and/or SU #2 transformer high side
. voltmeters on panel 2C10:
[ 'The magnitude of the high side voltage on SU #2 or SU #3 will dictate how much load (if any)~can be
.placed on.the vital ESF buses. The criteria for the minim'um voltage allowed'on'.the'ESF. buses is' ~
adesign,ed to protect the equipment from
'high amperage, which could cause overheating of the m.
motor, or could challenge the setpoint of; protective ~ R
~
cire'uits such'as' fuses or circuit breakers.- I f V d w; 2: m 'WP84989' 'SECTION VII - 4.0- PAGE 30
'Y
- V
'A) Monitoring the high side voltage indications on 2C10, use the following criteria for quidance:
- 1) If high side voltage is:
> 19.5 KV on.SU #3 - OR > 141.5 KV on SU #2
- GO TO STATEMENT *
- This statement directs the operator to " Step 7" of this tab. The above *
- voltage is.high enough that it should not trip the undervoltage devices on *
- the ESF buses, and should allow loading as required. While adding
- additional load to the transformer, voltages on the transformer and the *
- buses.should be monitoring to ensure the undervoltage trip setpoints are *
- not challenge'd. *
- 2) If high side "oltage is:
> 18 KV but 3 19.5 KV on SU #3 .O
_R
> 131 KV but 5 141.5 KV on SU #2 . (-- . Q/ - .WP84989 SECTION VII-- 4.0 PAGE 31
+ -\-[ )\ '*
GO TO STATEMENT' *
- This statement directs the operator to " Step 13" of this tab. The above *
- voltage will probably require defeating the under voltage devices on the *
- ESF buses, but;is high enough it should not cause any damage to the- *
'* equipment.> While adding additional load to the transformer, voltages on *
- the transformer and buses should be monitored. The voltage on the 4160V *
- buses should be above ~ 3480V and the voltage on the 480V buses should be
- above ~ 400V, if the transformer voltage is kept above 18 KV on S/U #3 or
- 131 KV on S/U #2. *
- 3) If high side voltage is:
<.18 KV on SU #3 . f3 OR \.J . < 131 KV on SU #2 *******x***********************************************************************
- GO TO STATEMENT
- THIS' STATEMENT DIRECTS THE OPERATOR TO " STEP 17" OF THIS TAB.
IF THE HIGH *
'* SIDE' VOLTAGE IS LESS'THAN THE ABOVE VOLTAGE, THE ESF' BUSES SHOULD HOT BE- *
- ENERGIZED BECAUSE OF THE PROBABILITY OF DAMAGING EQUIPMENT.
- L)\
WP84989 SECTION VII -~4.0 PAGE 32 k
Oh ch ~ ' . 1 yy; - STEP 7~ Place handswitches for CCW. pumps 2P-33A, 2P-33B' and
; t7]. _;> 1.. '2P-33C in " Pull-to-lock":
g This action is taken becauseithe next steps are going
, .to attempt to re-energize buses. The'CCW system may . restart when the buses are energized. The CCW system is secured to prevent thermally shocking the RCP 3
seals by the sudden restoration of cooling water c; -
; flow. JA~ rapid cooldown of the RCP seals may cause
_ failure of seal components and excessive seal leakage. , If high side voltage indication on panel 2C10 is: STEP 8:
, ,> 19.5 KV on SU #3 transformer, jt QR-su. -
, R. , '> 141.5 KV on SU #2 transformer.
.Then, energize 4160/480V buses from an va'ailable:
s
, sta'rtup transformer T ~
If.the-high side voltage. meets the above. criteria,
~
thi 4160/480V buses should be capable of being loaded twithout tripping the undervoltage protection devices. The preferred S/U transformer:is S/U #3.
~ - ~
A). IF SU #3 is the available transformer, close
.~'g . .k ' . the following breakers on Panel"2C10:
23 ,
- 1)f 152-113.to energize bus 2A1 y,
AND 152-213 to energize bus 2A2. ([ 2)_ WP849891 'SECTION VII - 4.0 .PAGE 33
.,~, ~
l NOTE l l This~ note directs the operator to coordinate with Unit I to prevent the l ll overloading of S/U #2. If SU #3 is unavailable and the buses are l
'l re-energized from SU #2, close attention should be given to SU #2 loading l l to prevent exceeding its limits. The loading of SU #2 should be l l coordinated with the Unit 1 control room when both Unit 1 and Unit 2 are l -l relying on it for power. The rating of SU #2 is 45 MVA with forced air l l and forced oil cooling. If the fans and oil pumps are not available, the l l rating is reduced to 27 MVA. The MVA load on the transformer is calculated l l as follows: l l MVA = KV x A x f x 10-3 l
- l l l - KV = high side voltage from Unit 1 meter l l A = SU #2 current from Unit 1 meter l l
f = 1.73 l
- 4 10-3 = 1 x 10-3 (This converts KVA to MVA.)
l Additionally, the voltage on all buses should be monitored and a l l degraded voltage condition avoided by minimizing loading if necessary. l B) IF SU #2 is the available transformer, close the following breakers on panel 2C10: , 1)_ .152-111 to energize bus 2A1 AND
- 2) 152-211 to energize bus 2A2.
-l NOTE l l Hold the handswitch for breaker 2A309/2A409 to the " Closed" position for at'l l'least 3 seconds to allow the bus to energize and the undervoltage relays l_
l-to reset. l b) v WP84989 SECTION VII - 4.0 PAGE 34
, ,e s C) Energize the 4160/480 volt ESF buses v)
- 1) = Energize ESF buses 2A3 and 2B5.
a) Verify 2DG1 ou'put t breaker 2A-308 is open and in " pull-to-lock." b) Turn synchronizing switch for breaker 2A-309 en panel 2C33 to on. c) Close breaker 2A-309 using handswitch on panel 2C33. r d) Verify 2A3 and 2B5 are energized. AND
- 2) Energize ESF buses 2A4 and 2B6.
;(~k >-]
a) Verify 2DG2 output breaker 2A-408 is open and in " pull-to-lock." b) _ Turn synchronizing switch for breaker
-2A-409 on panel 2C33 to on.
c) Close' breaker 2A-409 using handswitch on 2C33. ' d) Verify 2A4 and'2B6 are energized. Energization of the ESF huses gives the operator the ability to coamence restoring
, RCS support systems. This allows analyzing and controlling all parameters necessary to r ) satisfy required safety functions.
WP84989 SECTION VII - 4.0 PAGE 35 c :-
STEP 9: Restore RCS support systems as required:
./ s1 LJ The restoration of RCS support systems allows establishing control of safety functions to ensure core heat removal is maintained. RCS inventory and RCS pressure will probably require immediate attention after electrical power'has been restored to ESF buses. If conditions allow restoration of non-vital loads will assist in controlling safety functions. For example, regaining control of various valves requires restoration of instrument air. CCW is required to cool IA compressors and for RCP seal cooling. If possible, RCS forced flow via RCPs is f desired. \
A) Place charging system in service and verify' pressurizer level is being restored and maintained at 41% by starting and stopping
' charging pumps:
4 The charging pumps have a 50-second time delay before they can be restarted after regaining
. power. Since : letdown is isolated, the pressurizer level control system car.not maintain pressurizer level. The charging pumps must be started and stopped to maintain pressurizer level at approximately 41%. -WP84989 SECTION VII - 4.0 PAGE 36
m f-q; B) Restore pressurizer pressure to 21800 psia but
~
(_) s-2300 psia: RCS pressure control is required to keep the reactor coolant-subcooled so that the coolant is
. in the preferred state to transfer heat from the core to the S/Gs. This step addresses the RCS pressure control safety function and supplies information to ensure that it is maintained within the desired band. Pressurizer pressure will be maintained by use of the proportional heaters and the auxiliary' spray valve, until the RCPs are started which will' allow returning normal spray to service.
{
- 1) Verify pressurizer level 2 29%:
Pressurizer level must be above the heater cutout. level of 29%L to allow the pressurizer heaters to be placed in service.
- 2) Place the pressurizer proportional heater 4
handswitches on 2C04 to "ON" to regain control of the proportional heaters: f
.When an undervoltage condition is sensed on '( 2B5 and 2B6 the' proportional heater IWP84989. SECTION VII - 4.0 PAGE 37
7-9 , breakers open. Placing the handswitches on k,)
.2C04 to "0N" will close these supply . breakers allowing the proportional heaters to control pressurizer pressure.
Pressurizer level must be > 29% to gain control of the proportional heaters.
- 3) Place the pressurizer backup heater handswitches to "off".AND back to " auto" OR "on" to regain control of the backup' heaters :-
The pressurizer backup heaters will need to ("'y have the handswitch taken to "off" and then
.A l back to " auto" or "on" to allow the breaker to shut.
i-C)' If available, place EFW pump 2P-7B in service
, and secure 2P-7A, unless 2P-7A is needed for RCS temperature control:
2P-7B-will' auto start when power is restored to
^
2A3 after a 90-second tLee' delay if the EFAS D
- signal has not been reset. 12P-7A.should be secured and:2P-7B should be'used to control S/G
' levels unless 2P-7A is r.eeded ~ as a steam' load to
(/ X ,/'., assist in RCS temperature control. WP84989 ,
.SECTION VII - 4.0 PAGE 38' m
r .-
,, r3 D) Verify a SW pump has. started and SW system is ' \.J .
operating properly: The service water system should return to a normal lineup with a pump being powered off of 2A3 and 2A4. ' The SW alignment can be checked by verifying:
- Two service water pumps running, taking a suction on either the lake or the emergency pond. - Service water return aligned to either the lake, the emergency pond or the cooling tower. - 2PIS-1417-1 (Loop 1) and 2PIS-1423-2 (Loop 2) /~' is > 55 psig (low pressure alarm) and < 118 psig
- V)
(high pressure alarm) on 2C16 and 2C17. E) Verify any required-ESF equipment has started and is operating properly. The ESF equipment that is required will have to , be determined by the operator. The required ESF-equipment will depend on what ESFAS signals, if any, are present. The operator will have to determine from the plant parameters and alarms which equipment should be running. y- !; b p
- WP84989 SECTION VII - 4.0 PAGE 39
=
7 t
.f c) F) Place Loop II CCW system in service as follows.
V ,
- 1) eClose CCW containment return header isolation valve (2CCW-150) (located in upper i north piping penetration room).
- 2) Restart condensate transfer pump (2P9A or i 2P9B) for CCW expansion tank makeup.
- 3) Restart a CCW pump to provide flow through ,
Loop II CCW.
- 4) Verify SW is aligned for CCW heat exchanger ]'
l' cooling.
- 5) Monitor Loop II CCW expansion tank level.
/~T CCW is restored to provide cooling for the RCPs, \~)
letdown heat exchanger and instrument air l' compressors. . Isolation of 2CCW-150 will prevent thermal shock to the RCP seals when_the CCW pump , I is started. If "C" CCW pump is not available, then using IA operated suction and discharge ;! crossconnects for the other CCW pumps to supply. l Loop II CCW is required. This will require starting an IA compressor first. IA compressors are CCW cooled and will run only a~few minutes without CCW. Coordination of starting IA and CCW will be required to ensure ' cooling is
. supplied to IA compressors as soon as possible. I i 'WP84989 SECTION VII - 4.0 PAGE 40 i
a r- : . G) Restart one instrument air compressor and place
.. (
the instrument air system in service. e Instrument air is restored to allow operation of i various control valves such as the SDBCS valves, l RCS letdown, etc. l-6 H) Restore CCW flow to RCPs as follows:
- CAUTION .
l
. RCP SEALS SHOULD BE COOLED SLOWLY TO PREVENT DAMAGE TO THE SEALS. . . RCP SEALS MAY HAVE HEATED UP TO NEAR RCS (T C * . EXISTED FOR A' SUBSTANTIAL TIME FRAME.
- l l( };
Slowly open 2CCW-150 to establish a small I
- 1) -
amount of.CCW flow to the RCP seals. '
?
- 2) Monitor RCP controlled bleedoff and lower- ,
I seal temperatures to establish a slow cooldown rate. I 3). When the RCP seal temperatures have 1 stabilized, fully open 2CCW-150. P , p) (_ r-WP84989- SECTION VII - 4.0 PAGE 41 i
A i , I) Re-energize 6900 V buses 2H1 AND 2H2 from an 9;j J3 e available startup transformer: ~
'This step provides power necessary to establish RCS forced flow conditions. This also provides s
l for further restoration of support systems. l J) Restart at least one RCP in each loop ifi ! 1) RCP restart criteria are satisfied per. Appendix H: Appendix H criteria should ensure all j'
' conditions required for RCP operation.are' . ['^ .
satisfied. - i;
.t
- 2) .S/U. transformer. load capacity is available:
This step addresses both' transformer load -!
. capacity and system voltage considerations.
a) Each RCP represents ~ 5 M7A of additional lead: This information is provided to allow the operator to evaluate the present~ ql
/t . load on a S/U transformer and ensure A.) , '.WP84989 : SECTION VII - 4.0 PAGE 42~ .
t z,- it will not be overloaded when a RCP Y). is running in addition to the present
, load.
b) If both units are on S/U 2, coordinate with Unit 1 to ensure S/U 2 MVA limits are not exceeded: 45 MVA with forced air and forced oil cooling: 36 MVA with forced air cooling: E
~%
27 MVA without forced air cooling:
. ()_ \
The only time transformer overloading is expected to be a problem is when both units are on S/U #2. The only time S/U #3 loading could be a problem is if no forced air ~and forced oil cooling can be established.
- c) If it appears that with additional transformer loading the steady state 4160 V bus voltage will decrease below ~ 3800 V, no more loads should be started -] ). , until voltage conditions improve: -. WP84989 SECTION VII=- 4.0 PAGE 43
- y. - - - -
n;. g r;r-) If at least 3800 V are maintained on
' 'bi the 4160 V buses, 2A3 and 2A4 should ggl , be able to be. supplied by off-site power. This voltage is above the i a ' reset value for the 2B5/2B6 UV l ,, relays. This step is a reminder to j 1
monitor system voltage while placing additional loads on the electrical i system. If off-site power supply lines are limited or voltage is l. i. abnormally low, the' operator may not want'to start large loads to prevent further system degradation. .' c l[s_.e -
\- .
d) The following table of thumb' rules may !' I r be' helpful in determining transformer t loading: , t. s l INPUT . - l - 4 5. MVA . l AMPS PER I AMPS PER l AMPS PER l
. . "l~ VOLTAGE l AMP' LIMIT l RCP l CW PUMPJ l COND. PUMP l t'
- l. l -l -l l l-l'161 KV 'l 161 A l 18 A l 21 A- :l- 11 A l l
l- 1 l l I . I Ll'141'.5 KVl ~ 184 A l 20 A l 23 A l 13 A- l This table lists the number of amps that-correspond to the 45 MVA load limit for two voltage' conditions. I:
.A K)
WP84989'* SECTION VII - 4.0- PAGE'44 l 'h
~
4 C Data is given for the 161 KV condition -l c:r$);" A" l since this is the normal supply ~ l
, voltage to S/U 2. Data is given for the 141.5 KV condition since'this is i the lowest voltage that will allow the -l use of S/U 2. The amp limit is given .l, for the 45 MVA condition because it is very likely that forced air and forced ,
oil cooling will be available. The amp values given for the RCPs, CW l pumps and condensate pumps are
'e approximate values that one of these 6. ' pumps running will increase S/U 2 -l /~j --/.
amperage by. . 3
'RCPs-are restarted to provide forced flow '
circulation.to remove core-decay heat. If. . 1: S/U'3 is ava'ilable with normal system voltage,'all~4 RCPs.may be restarted'to .I help ~ maintain Hot Standby conditions. . l-
= ,j-4 G <f -sy . ,_
A.f ~ _ie
- WP84989- SECTION VII - 4.0 PAGE 45' 3
f. y_, e 2-
m 4
- g 4 Y
rA K) Monitor RCP seals for proper operation: N
RCP segl operation is monitored because the seals may.have experienced a large thermal -transient. This thermal transient or just the l'
fact that the RCP lost-power and stopped may l have caused a seal failure. t L) If possible, place the letdown system in service: The letdown system is placed in service to allow
~
automatic control of pressurizer. level.
~ "'j STEP 10:' -Restore-Secondary Systems to normal operation as. - v follows:. -
Place the circulating Water System in operation 0 A)
. , Y v per OP 2104.03. ,. ' ^
B)- Place the Condenser Vacuum System in service and
establish' condenser. vacuum per.OP 2106.10. ji
[C) Place the Feedwater.and. condensate' System in
. service on short path rebirculation through a
+ demineralizer'per OP-2106.16.
. D) . When . power is regained, reset SDBCS- system per
,; _ OP'2105.08,- Section 6.7 AND establish steam flow
+ . .through_ turbine bypass valve (s): to .the 'consenser .for 'CS.
R temperature controle (
; J - . WP84989- . SECTION VII - 4.0 PAGE'46~ ~
r O' x u
. ,,ss .
E) IF desired, shift EFW pump suction to demineralizer 4 7' t, outlet:
+.
The above steps'should re-establish the main condenser
- as the heat sink for_the secondary. This is desired
.so that secondary inventory can.be maintained. l ~
- lGO TO STATEMENT *
- This statement sends the operator to the " Reactor Trip Recovery" tab. Now a
- that power has been restored, the operator can verify all his safety
~
l.
- functions.
- I
, ,Q - l NOTE l \J ~
l This statement directs the operator to strip only one train of buses. This l L l;is done because at this time the operator's concern is' to get power back to l t' l at least one tr' ain of ESF buses to regain control of pressurizer pressure l , I l and level'. l
' STEP 11: Strip 4160 volt bus 2A1 (preferred) OR 4160 volt bus i 2A2 of'all loads (EXCEPT for Load Center 2B9 OR Load Center 2B10 for pressurizer heaters):
2A1 is the preferred bus to strip because it will enhance _the ability-to restore power to EFW pump 2P-7B (powered from 2A3). Since this is restoring power in a degraded voltage condition, the stripping i t r% WP84989 SECTION VII - 4.0 PAGE 47 i-
m }"< 7-,3 _ lof the bus is performed to ensure minimum load on the i,j . s
. buses when power is restored. The following steps are designed, to allow the stripping of 2A1 or 2A2 from the control room. This eases operation and i
maintains remote control of the above equipment. I l. A) Strip 4160 volt bus 2A1 (preferred) of all loads (EXCEPT for load center 2B9 for pressurizer 4 heaters)'. I
- 1) - On 2C-10 place the following breaker handswitches in " pull-to-lock" AND verify the breakers open. ,'
152-102 (^} a) 2A1 to 2B1 152-103 l b) 2A1 to 233 - c) 152-104 2A1 to 2B7 ' l
~ .2)._
On 2C-02 place the following handswitches in " pull-to-lock" MG verify the breakers !- 1: open. l a) 2HS-0609 condensate pump 2P2A b) 2HS-0614 Condensate pump 2P2C c) 2HS-0730 Heater drain pump 2P8A t i ji
. WP84989 SECTION VII - 4.0 PAGE 48' i
w 7~
- 3) On panel 2C-22 place the following
~;V ~ -
handswitch in " pull-to-lock" AND verify the
- 1. : ,
; brgaker open.
a) 2HS-3810 Main chiller 2VCHIA= I OR I B) Strip 4160 volt bus 2A2 of all loads (EXCEPT for- -l load center 2B10'for pressurizer heaters).
- 1) On 2C-10 place the following bre har handswitches in " pull-to-lock" AND verify the breckers open.
I 152-202 s a) 2A2 to 2B2
, b) 152-203 2A2 to 2B4 c) 152-204 2A2 to 2B8 ' --- (s...
- 2) On 2C-02 place the following handswitches .l in " pull-to-lock" AND verify the breakers i open. ,
I a) -2HS-0620 Condensate pump 2P2B
- b)~ 2HS-0626 Condensate pump 2P2D !
c) 2HS-0722 Heater drain pump.2P8B
-3) On 2C-22 place the following handswitch in " pull-to-lock" AND verify the breaker open.
a) 2HS-3812 Main chiller 2VCH1B i O 4 t/ WP84989 SECTION VII'- 4.0 PAGE 49 i E b
~ - ; = ~,, ;-g ; ' STEP 12: If S/U transformer:high side voltage indication on ..i 4- %_L ~
a Panel 2C10 is degraded: F r 2 18 KV,but < 19.5 KV on S/U #3 transformer q OR l: 2 131 KV but < 141.5 KV on S/U #2 transformer -l A). Energize the desired'4160 V buses from an available=S/U transformer. .
- 1) If S/U #3 transformer is available:
.a) Turn synchronizing switch l-152-113/152-213 to "on." .b) Close the feeder breaker to energize the desired bus and check bus voltage on ' ' /"'E 2C10. ' \~,! -'
_O_R
- 2) If S/U #2 transformer is available:
a)- Turn synchronizing' switch ,
't 152-111/152-211 to "on."
b) Close' the. feeder breaker to energize !: the desired bus and check bus voltage on 2C10. 1 This step energizes the bus stripped in Stop 13 from an available S/U transformer.
. ., If both transformers are available, but degraded, the least degraded transformer should be used. Also, if possible~, S/" #3' 5.
Jt3 k.J . * ~ WP84989- SECTION VII - 4.0 FAGE 50 i s
<y =. >
p v c should be used since it has a greater load N/ -
, capacity and will be preferred once normal j volt; age is restored. 'a t B) Defeat-undervoltage relay trip signals to ESF l
[. bus feeder breaker 2A309 (preferred) or 2A409. .i
.s i 1) . For- ESF bus 2A3 feeder breaker (2A309):
a) At breaker 2A308, open test switch , TS2-308E to defeat trip signals.from 2A3 undervoltage relays A-127-2A3/B-127-2A3. I b) At Panel 2C33, open test switch TS9-3
~
to defeat trip signals from 2B5 9 undervoltage relays 2B5-27-1/2B5-27-2. '[ Ej]: OR
'J ~ * . l.
- 2) For 2A4 feeder breaker (2A409): ~ -
a) At breaker 2A408,' open test switch
^
TS2-408E to-defeat trip signals from-2A4 , I
~
undervoltage. relays A-127-2A4/B-127-2A4. L1; b) At panel 2C33, open test switch TS8-3 to defeat trip signals from 2B6 l-undervoltage relays 2B6-27-1/2B6-27-2. These test-switches are opened to allow 2A309/2A409 to be closed and to prevent them from -tripping when loads are started. With voltage in the above range, the 2B5/2B6 UV relays may still be tripped or i 71-3.u
-WP84989' SECTION VII - 4.0 PAGE 51
[
a . y >
;j 3.. , may.not be reset. This will keep a trip Q' ) present on 2A309/2A409. The test switches on.2,C33 are opened to remove this possible trip from the 2B5/2B6 UV relays. With i-voltage in the above range, the 2A3/2A4 UV-l.
relays may or may not reset. Voltage i should be above their trip setpoints. The
~
tes.t switches on 2A308/2A408 are opened to remove this possible trip from the 2A3/2A4 UV relays. Even if the 2A3/2A4.UV' relays did reset, it is a concern that'they may trip due to the voltage dip when loads are e started. This is another reason the test. f J -if switches are. opened. . Test switches are
~b 'j used t.o defeat.the trips instead of fuses being pulled to de-energize relays to I defeat the trips because it_was considered. ',
easier and safer to_do.it in this manner.
'C) Energize the desired 4160/480 volt:ESF buses. l
- 1) Energize ESF. buses 2A3/2B5.
a) Verify 2DG1 output- breaker 2A308 is - open and in " pull-to-lock."' b) Turn synchronizing switch for breaker -
-2A-309 on Panel 2C33 to "0N."
l' I n
\) . ~ WP84989- .SECTION VII - 4.0 PAGE 52 , i Ov+ -
____..__.______u_.__-.._-__._______..______. _..m _ - _ _ _ ___m._____m__.t___ .____,. _ _ _ . _ . _ - - _ _ _ . _ _ _
l 1
-s c) Close breaker 2A-309 using handswitch N
on Panel 2C33. d) , Verify 2A3 and 2B5 are energized. OR i
- 2) Energize ESF buses 2A4/2B6.
a) Verify 2DG2 output breaker 2A-408 is j open and in " pull-to-lock." b) Turn synchronizing switch for breaker 2A-409 on Panel 2C33 to "0N." c) Close breaker 2A-409 using handswitch I on Panel 2C33. d) Verify 2A4 and 2B6 are energized. Once either 2Al or 2A2 is energized, 2A3 or (C v_: 2A4 is energized. This will achieve the main goal of this step which is to provide I power to ESF equipment such as charging t pumps and to the pressurizer heaters. , I Prior to closing 2A309/2A409, the EDG output breakers, 2A308/2A408, are placed in f
" pull-to-lock" to ensure these breakers do l
not close if the EDG is started. The l automatic close signal on UV may remain present to 2A308/2A408. If not in
" pull-to-lock," the only thing preventing the closure of these breakers once the EDG starts is 2A309/2A409 being closed. g
.g WP84989 SECTION VII - 4.0 PAGE 53 i
{FTI + 4 1
- 3 STEP 13: Restore necessary RCS support systems to establish. '~i~ and maintain RCS ' inventory and pressure control.
A) Place charging system in service and verify i pressurizer level is being restored and I maintained at - 41% ay starting and stopping l charging pump. Once 2B5 or 2B6 is energized, power should be available to one or two charging pumps. Charging pumps are needed to replace the, RCS inventory loss due to RCP CB0 and to contraction due to cooldown. If the 2A3/2A4 UV relays have -
;- } not reset, the charging pumps will have to be ,
u x. - q operated locally at'the breaker. No indication for the charging pumps will'be available in the t control room in this situation. The' normal no , I lead pressurizer level ~of 41% should be maintained. This will provide. adequate ll
inventory and will allow pressurizer heater
- l .
operation. l t L6
. L V.
WP84989- SECTION VII - 4.0 PAGE 54 t
e ..
~
Ly p B) ' Place available pressurizer heaters in service *
~ l._ f and maintain pressurizer pressure within limits - of Figure 1 i
- 1) Place the following selector switches to .
the energized bus. i a) Pressurizer level channel selector switch (2HS-4626). , b) Lo-Lo level cutout switch (2HS-4642). c) Pressurizer pressure control channel l. selector switch (2HS-4628). 8
- 2) Place proportional heater handswitches to ,'
(
>~j:- "0N" to regain control of the proportional ,
heaters. i
- 3) Place the backup heater handswitches to .
I "0FF" and back.to "AUT0" or "0N" to regain control of the backup heaters. ! Once 2B9 or 2B10 and 2B5 or 2B6 are energized,
- l power will be available to a portion of the pressurizer heaters. Pressurizer heaters are necessary to restore and maintain RCS pressure to maintain the RCS in a subcooled state. Power
- is left available to the pressurizer -
proportional heaters to ensure adequate heater- $ r\ L) i-WP84989 SECTION VII - 4.0 PAGE 55 i O:
capacity is available. If the 2B5/2B6 UV relays I ). 27X/2B5 or 27X/2B6 are tripped or are not reset, the proportional heaters will not be available. To allow operation of these heaters in this -i sitution, the test switch TS2/B5 or TS2/B6 in 2B5/236 must be opened. This is not expected to j be required but may be a possibility. - The above pressurizer level and pressure control channel . selector switches should be placed in the position corresponding to the energized bus to I l' allow possible automatic control of heaters and to remove possible interlocks preventing their operation.
. CAUTION 'e '
THIS STATEMENT REMINDS THE OPERATOR THAT ONLY EQUIPMENT THAT IS r
* , ABSOLUTELY NEEDED FOR THE SAFETY OF THE PLANT SHOULD BE STARTED. * 't THIS IS BECAUSE UNDERVOLTAGE CONDITIONS MAY EXIST AND UNDERVOLTAGE *- . ' PROTECTION MAY BE REMOVED. DAMAGE TO MOTORS DUE TO EXCESSIVE . 'l . CURRENT IS POSSIBLE IN THIS SITUATION. * -l I*
e n WP84989 SECTION VII - 4.0 PAGE 56 i h I
/
L): l NOTE l llIn order to' energize 4160 volt ESF motors, the undervoltage trip signal to l l its respective-breaker may need to be defeated by opening the ypropriate l l; test switch. l 1:
- l 2A3 l ll l 2P-4A "A" SW Pump TSI-309B l
-l 2P-4B "B" SW Pump TS2-308B l . -l 2P-7B "B" EFW Pump TS2-308F l .l 2P-35A "A" Spray Pump TS1-309C l l= - l 2P-60A "A" LPSI Pump TS2-308C l l 2P-89A "A".HPSI Pump TS1-309D l B -l 2P-89C' "C" HPSI Pump TS2-308D l 8 -- ; l 2A4 l -.C ;l 2P-4B -"B" SW Pump TS2-408B l -l 2P-4C "C" SW Pump TS1-409B l I
- l 2P-35B -"B" Spray Pump TS2-409C l ,
I l 2P.-60B "B" LPSI Pump TS2-408C l if2P-89B "B".HPSI Pump TS1-409D l [
'l 2P-89C "C" HPSI Pump TS2-408D l .[ .l. l .-l This note provides the operator-with the information necessary to defeat l l the UV trips on the ESF pumps powered from 2A3 and 2A4. This action may.be l l necessary if the*2A3/2A4 UV relays have not. reset and one or more of the l r.
I above pumps are required to be.run. The location of the test switch is l l included in its number. . EXAMPLE: TS1-309B is located on the front of l' i
- l breaker'2A309 onI2A3.- l LWP84989 SECTION VII - 4.0 PAGE 57 -
,_ 1C) IF necessary, start other required loads while I^ ").- L monitoring degraded voltage condition.
This step, along with the preceding step, allows. the operator to start any ESF loads-which may be
. required to maintain the plant in a safe condition. The operators will be monitoring plant parameters and if-conditions develop that require the use of ESF equipment, the operator can start any equipment he feels is necessary. to maintain core cooling or minimize the release of radiation. The reduced voltage condition may not allow all equipment to be operated. .The r-] decision as to which equipment is operated is ..v left up to the operator and will be made based upon existing plant conditions.
STEP 14: Maximize efforts to make an EDG operable and/or
. restore an_off-site power. source to norma'l voltage IT conditions:
In order to reach this step an off-site degraded voltage condition exists and has been used to re-energize one ESF bus. This allowed running any necessary loads that required defeating undervoltage
. protection on some components. The following steps address regaining of an EDG, either the energized or . ]J WP84989 ~SECTION VII - 4.0 PAGE 58 g
r
?js de-energized side, and also discusses regaining normal Q): off-site voltage.
s
- 1) If the EDG associated with the de-energized ESF buses is made operable:
9 If EDG on the de-energized ESF bus is operable then tying on the EDG to the ESF bus immediately is desired. This ensures that protected ESF ( equipment is available for use. The following
\
steps also' address removal of degraded voltage and restoration of undervoltage test switches. f(y a). Energize the associated ESF buses by V-closing the output breaker. b) Start required ESF equipment. c) If desired, degraded voltage may be removed from the opposite ESF buses.. d) If desired, degraded voltage may be used to energize.non-vital loads (e.g., CCW and IA). e) When equipment powered from1the degraded voltage is secured, close the undervoltage test switches, if opened.
-~
v WP849G9' SECTION VII - 4.0 PAGE 59
C b p l-I
; ~s ;2) ' _ If the EDG associated with the ESF buses, + ).
' \_/ E . powered by the degraded voltage, is made operable: ., i'
- If an EDG is made available on the ESF bus that has degraded voltage then removal of the degraded voltage is required before using the EDG. Restoration of undervoltage test switches will also be required to ensure a protected ESF c
bus is available. The following steps address these concerns. a) Stop ESF components energized by the
.(-} degraded voltage. %s
! b) Open normal feeder breaker 2A309/2A409. c) Close the undervoltage test switches opened
- l. in previous steps.
[ d) Close EDG output breaker 2A308/2A408. l' (Breaker may automatically close when removed-from " Pull to Lock.") ,
- e) Verify required ESF equipment starts, p
- GO TO STATEMENT
- r
<* If an EDG 'is made operable, place it in service and go to Degraded Power
- L.
- tab.
- h
,-{ v L WP84989' SECTION VII - 4.0 PAGE 60 ) m
_ j-q B) Maximize efforts to restore an off-site power source to normal voltage conditions: The following steps address restoring systems to i normal if off-site power is returned to normal voltage conditions. Of particular concern is i returning undervoltage test switches to normal. Handswitches for CCW pumps are placed in
" pull-to-lock" to prevent CCW pump restart and possible thermal shock to RCP seals when I
re-energizing non-vital load centers. i
- 1) If an off-site source is restored to normal l
T voltage conditions:
sI . a) Close undervoltage test switches _l opened in previous steps. ,' b) Place handswitches for CCW pumps , t 2P-33A, 2P-33B AND 2P-33C in
" pull-to-lock." !
c) Energize load centers stripped in l Step 11. GO TO STATEMENT *
- Direction to Step 8.0 of this tab provides guidance for restoring the
- de-energized electrical side. *
.******************************A************************************************ {
(3 v.' WP84989 SECTION VII - 4.0 PAGE 61 i
j- STEP 15: If off-site power cannot be restored: L-l-If this step is , reached then the EDG(s) and off-site power was not immediately recoverable. Actions to
, verify safety functions and maintain them has been . performed. Safety functions can be maintained in a blackout condition for a finite period of time. In particular, the continued loss of RCS inventory control and RCS pressure control will be degrading as RCP CB0 is lost via a relief valve to the quench tank.
Direction is provided in the following steps to attempt to restore some form of power to ESF bus (es), attempt to control the RCS inventory safety function (~')_ and minimize load on station batteries.
.v A) Maximize efforts to make an EDG operable and/or restore an off-site power source:
Restoration of some power to an ESF bus will eventually be required in order to ensure that safety functions are maintained. All available efforts to restore some form of power to ESF bus (es) will be required. U WP84989- SECTION VII - 4.0 PAGE 62
,_s *******************************************************************************
- ( \
'* GO TO STATEMENT
- Recovering one or both EDGs will restort the ESF buses 2A3 and/or 2A4. *
- This Go To Statement will direct you to the degraded power tab if an EDG is *
*l restored. .The degraded power tab supplies information necessary to maintain * * , safety functions.with one or both EDGs available. *
- GO TO STATEMENT *
- If an off-site power supply is made operable, go to Step 6 of this tab. *
- This will direct you to a step where evaluation of S/U transformer voltages *
- are perfor~ed. Based upon the condition of off-site power supplied to S/U
- transformers, direction will be provided for recovery of ESF buses. *
(g ******************************************************************************* (,/
. CAUTION . . DO NOT ATTEMPT A COOLDOWN . . NO RCS MAKEUP CAPABILITIES ARE AVAILABLE TO ALLOW BORATION FOR . . SHUTDOWN MARGIN OR MAKEUP.DUE TO SHRINKAGE ~DURING THE COOLDOWN. . . THERE WILL BE NO MEANS TO PROVIDE EFW FLOW WHEN STEAM PRESSURE IS . . TOO LOW TO DRIVE THE EFW PUMP. .
J WP84989 SECTION VII - 4.0 PAGE 63 f
+ ,s B); Maximize efforts 'to provide emergency RCS makeup capabilities by one or more of the following methods: ,
- 1) Portable diesel / gasoline powered pumps with sufficient discharge pressure.
- 2) Air operated hydro pumps with portable diesel / gasoline powered air compressor.
3)- Large electric hydro pump with portable diesel / gasoline powered generator. r If a blackout condition is prolonged, eventual RCS makeup ability will be required. (- C) Consider a reactor building entry to' isolate'RCP V] CB0 relief to quench tank by closing 2CV-4856:
- If restoration of power is expected to be -prolonged, isolation of 2CV-4856, vh'ich will . minimize RCS inventory loss via RCP'CB0 flow should be considered. '
D) .To limit the drain on the station batteries, the following actions should be considered: The following steps is a list of actions which will minimize the DC powered loads and thus [{ prolong'the battery power. These should be WP84989 SECTION VII - 4.0 PAGE 64 i, Y_
t - 6- ;
/ r secured as desired. The plant computer is one Jp-)q.
i\_
-of the largest, loads on the battery and although ~
some of its, readings may be desirable, it should be considered heavily for securing.
- 1) . Venting of main generator hydrogen
~
pressure, purging with CO 2, and stopping DC
. powered seal oil pump 2P-21. (Refer to OP 2106.03)
- 2) Securing feedwater-pump DC powered lube oil pump (2P-28) when pumps have stopped.
- 3) Securing main turbine DC powered lube oil pump (2P-20) af ter main turbine has coasted down and stopped.-
. {}
- 4) Securing plant computer, if not required.
- 5) Securing any unnecessary DC powered ~1ighting.
9 6
,. L, - WP84989 SECTION VII - 4.0 PAGE 65 L.
E 5.0 OVERC00 LING RECOVERY ACTIONS A
- 5. J 5.1 Operational Goals The operational goal of the overcooling Tab is to provide interim guidance in handling a prolonged overcooling event that does not result in MSIS.
5.2 Description of Overcooling Overcooling is an uncontrolled decrease in RCS T . Overcooling. is caused by excessive steam demand resulting in more heat being removed from the RCS than is being generated by core decay heat. The steam demand could be a steam leak or, if early in core life with little decay heat, a normal steam load. It is also possible to overcool the RCS by overfeeding the S/Gs. 5.3 Safety Functions Affected j_ . Overcooling is a condition where heat removed from the RCS exceeds (~) heat absorbed by the RCS from the core, thereby affecting the RCS Heat Removal Safety Function. With the RCS cooling down, the shrink involved will affect the RCS Pressure Control and the RCS Inventory Control Safety Functions. The extent these safety functions are affected depends upon the rate at which the RCS is cooled. 5.4 Major Parameter Response A) RCS Tave Due to the excessive heat removal, RCS T,y, will decrease below the no load value of ~ 545*F and continue to decrease until the cause of the overcooling is corrected.
/O L.
WP84989 SECTION VII - 5.0 PAGE 1
._ _ . _ . _ . _ . _ . ..__.._.___...____.__..___.____.___.________[______.___.___.__ _ _ _ . _
,, B) RCS Pressure and Level Due to the decrease in T,y,, RCS pressure and level will decrease. The extent that pressure and level will decrease will depend primarily upon the rate at which T,y, decreases.
The decrease in pressure and level will be retarded somewhat by the automatic response of the pressure and level control systems. Should pressurizer level decrease to < 29%, pressurizer heaters will be de-energized by the pressurizer level low-low interlock. Level must be restored to > 29% and the heaters manually reset prior to their being used to
. help regain pressure control.
C) Steam Generator Pressure Since more heat is being removed from the secondary system g- than is being absorbed by the system, S/G' temperature will
~ i ,3u) decrease.'Since the S/G's are in a saturated condition,'S/G pressure will decrease.
D) Steam Generator Level After a reactor trip, one MFW pump will remain running at minimum speed with a 5% flow demand on the-FWRV bypass valves and a 0% signal to the main FWRVs. If left in automatic, FWCS will return S/G 1evels to 70%. If S/G levels drop to < 46.7%, EFW will be actuated and available to restore S/G levels. ON/ WP84989 SECTION VII - 5.0 PAGE 2 t
- E______-_____ __ _ _ _ _ . _- _ .'
r _ After a reactor trip, S/G 16 . Will drop rapidly due to
\/
the shrink resulting from the large load reduction. The
- size -of the event that will cause a prolonged overcooling will be within the capacity of one EFW pump so there should be no problem in maintaining S/G levels after the steps in this tab that have-the operator trip the HFWP and 2P-7A.
r-Operators should be aware of the fact that overfeeding the S/Gs could be a cause for excessive cooldown. If not the ! only cause of the overcooling, an excessive feedrate will magnify the overcooling event. 5.5 Bases for Overcooling Recovery Actions j ******************************************************************************* I
'e
- GO TO STATEMENT *
- THIS STATEMENT DIRECTS THE OPERATOR TO THE "HSIS" TAB IF THE HSIS SETPOINT *
- HAS LEEN R2 ACHED. ENTRY INTO THIS TAB WILL PROVIDE GUIDANCE TO THE *
- OPERATOR FOR SATISFYING THE SAFETY FUNCTIONS AND CONTROLLING THE PLANT *
- WITH A HSIS PRESENT. *
***A***************************************************************************
GO TO STATEMENT *
- This statement directs the operator to Step 2 of this tab if any of the *
-* actions taken in Step 1 stop the cooldown. This will prevent all of the *
- actions being performed if one of the initial actions corrects the *
- overcooling.
- WP84989 SECTION VII - 5.0 PAGE 3 f
i
STEP 1 . Attempt to stop the cooldown as follows: U Before any successful attempt at recovering the plant to normal post-trip conditions can be'made, the cause of the cooldown must be determined and corrected. A) .If necessary, shut the MSIVs prior to reaching the MSIS setpoint (s 751 psia): This step is presented first, not to imply that the operator immediately shut the MSIVs but, to remind the operator that shutting the MSIVs may prevent ang unwanted MSIS. This action not only prevents unnecessary safety system actuation, but
. v prevents further complication of recovery actions caused by MSIS actuation. If time permits, the following system and component isolations should be attempted prior to shutting the MSIVs.
B) Push the SDBCS emergency off pushbutton on 2C02: This action isolates a potential source of heat loss by calling for the SDBCS to shut all valves..
- 1) Verify SDBCS valves indicate closed:
Check valve positions on 2C02 for closed indi-- cations. WP84989 SECTION VII - 5.0 PAGE 4 u.__.________ ._____-i..__ -
,, r ' ' ,
p f
' 2) ' If a SDBCS valve does not indicate closed, locally 1.] ~
b-< check position and isolate, if required: If a check of SDBCS valve position on 2C02
'shows a valve to be open or intennediate position, the position should be verified locally. Any valve not found completely shut should be manually isolated.
c) Verify EFW-available to maintain S/G levels: This step has the operator check the EFW system
--for proper alignment and actuation, -as required, to ensure a method of maintaining S/G levels.
prior to tripping the running MFWP.
- 1) . Trip the running MFW pump.
This step has the operator trip the MFWP'if-
-EFW is available for S/G level. control to reduce-steam demand on.the MS system and to allow a slower rate of. feeding the S/Gs.
2)' :If 2P-7B is running, secure 2P-7As
!This step reminds the-operator-to verify-Joperation of 2P-7B prior to stopping 2P-7A -("sg to prevent a loss of all feed to the S/Gs.
n
' WP84989 'SECTION VII --5.0 PAGE 5 E e
m;--
~ ~3) override and throttle 2CV-1025-1 and 2CV-1075-1 -5_-
to maintain S/G levels constant: ith S/G-levels ~ 30% or greater, an effort should be made to maintain a constant level to prevent magnification of the cooldown by raising S/G levels. If levels are high,
. consideration may be given to allowing levels to slowly decrease to aid in. minimizing . the cooldown. +
D) Isolate Blowdowns'
,x; s
This step has the operator shut 2CV-1015 and 2CV-1065 - fr~s{I ' ls,J" ~
- n
~ , from 2C02 to remove blowdown as a source of cooldown.
E) 'Close the-MSR main steam supply valves, 2CV-0400 and-2CV-0460 on 2C12: This step has th'e operator shut 2CV-0400 and 2CV-0460 from 2C12 to remove the MSRs as a potential source of cooldown.
~ '-WP84989: SECTION VII -'5.0. PAGE 6 ~,
y h
<g
7..- F) Isolate steam to 2P-7A: This step has the operator shut 2CV-1000-1 and 2CV-1050-2 to remove'2P-7A as a load on the MS system and to isolate a possible source of leakage. 2P-7A should not be secured if it is needed to maintain S/G level. G) Locally inspect steam system. Attempt to locate and isolate cause of cooldown: This step has the operator walk down all accessable areas of the steam system in an attempt to locate the cause of the excessive cooldown and isolate it where possible. in STEP 2: If the cause of the cooldown has been determined and corrected, perform the following: A) Reset SDBCS and maintain T ~
.,t ave " * . SDBCS is reset by depressing the reset pushbutton on 4
2CO$ to allow the operator use of the bypass and/or
~
dump valves for controlling temperature at nc load T,,,. , N 1, e uli':; Q. s . - C/\ s
'WP84989 SECTION VII - 5.0 PAGE 7 y ':h- .. ; h. ,
B) If MSIVs were shut, equalize around and open the (7_], MSIVs: This step allows the operator use of the bypass valves for use in controlling T,y,.-
- 1) Operate SDBCS bypass valve (s) to control RCS temperature:
It is preferable to use bypass valves.vice dump valves to minimize secondary inventory loss.
-f^)(m/ . -
GO TO STATEMENT
- i..
- THIS-STATEMENT DIRECTS THE OPERATOR TO STEP 6 0F THE " REACTOR TRIP RECOVERY"*
~
- TAB AFTER THE 0VERC00 LING CONDITION HAS BEEN CORRECTED.
+ = '()\
f L WP84989- SECTION VII - 5.0' PAGE 8 y
~
e
,. 6.0 MAIN STEAM ISOLATION RECOVERY ACTIONS !\ ^) 6.1 Operational Goals The operational goals of the main steam isolation (MSIS) tab are to provide guidance for the termination and control of excessive' steam demand events. ~ Primary objectives are to ensure automatic actuation of ESF systems, isolation of the cause of the event, and restoration of RCS safety function parameter control.
6.2 Description of Main Steam Isolation A main steam isolation event is an overcooling event, caused by an excessive steam demand, which has progressed to the point of MSIS actuation at 751 psia S/G pressure. It may be caused by the rupture.of a pipe in the main steam system, by a rupture in g the main or emergency feedwater lines-downstream of the last
~ )
check valve, or by the failure of a valve in the main steam system. The specific NSSS response-to an excessive steam demand event depends on a large-number of variables, including the sizing 4 and location of the rupture.or open valve, the operating conditions at the time-the event occurs, control systems
, status / response and operator actions, f
I
.f^ . ' WP84989 SECTION VII - 6.0 PAGE l' W v . _ - - - - . - _ _ _ - - - - - - - - . - - - - - - - - - - - - - - - - - - - - - - - - - ^^
For excessive steam demand events which occur downstream of the
' main steam isolation valves.(MSIVs), both S/Gs will be isolated from the break on an MSIS actuation signal and the overcooling situation will'-be terminated. Isolation of the excessive steam demand will result in a smaller RCS cooldown and a less severe impact on safety function parameters.
For excessive steam demand events which occurs upstream of the MSIVs, the closure of the MSIVs on an MSIS actuation signal will provide isolation of the unaffected S/G from any break associated with the other S/G and limit the high energy blowdown tio the contents of one S/G. By limiting the amount of high energy fluid release.d, the response of RCS safety function parameters will be less severe. A rupture in the main or emergency feedwater line downstream of the last check valve-is classified as an excess steam demand event because of a characteristic flow reversal in the
.feedwater line from the affected.S/G to the break. ' Blowdown through.the break is initially saturated liquid until the' feedwater nozzle is uncovered. The RCS cooldown will continue until the secondary inventory of the S/G is depleted.
,.J r (" . WP84989- SECTION VII - 6.0 PAGE 2 e a
e, l
. _q. The size of the break (effective steam flow area) and the secondary system pressure determine the blowdown rate and z . quality of the fluid released through'the break. Blowdown rate ' and fluid quality define the energy removal rate. Since higher fluia qualities may accompany smaller flow areas, a large hole may result in a smaller RCS cooldown than a smaller hole at the a same location. Since break size determines the rate of change E of thermal-hydraulic parameters, it also determines the effectiveness of various plant protection and control systems in mitigating the consequences of the event. Control systems can mask the symptoms of smaller excessive steam demand events that are within the capacity of the FWCS because a new steady state condition may be attained at a slightly' higher power /-~g' level with no reactor trip. Automatic actuation of a reactar sv trip on low S/G pressure, low S/G 1evel cnr containment pressure are less likely for smaller events because of slower pressure transients.
a Large excessive steam demand events are' generally characterized by rates of- change of parameters which exceed the capability of various control systems to regulate them. Consequently, the status (automatic or manual) and response of the plant control systems'have a minimum effect on large~ excessive steam demand
. events.
v v 'V: + WP84989. SECTION VII - 6.0 PAGE 3 f. o y ~ m y.- a % ,.i4 ,5-ey- ,-w w -+-q a6y--ww. ya y.-, ,.,--,,y,-,-p . .&n,& ,-..,s , e- -,,6a -w3
4 Hitigation and control of excessive steam demand events is 5
^) - accomplished through a combination of automatic ESF systems actuation, automatic control systems response, and operator actions. Depending on the location and magnitude of the event, the RPS may provide a reactor trip on high linear power, low pressurizer pressure, low S/G pressure, low S/G 1evel, high containment pressure, low DNBR, or high LPD.
Engineered Safety Features systems which contribute to event mitigation and control are the Safety Injection System, Main Steam Isolation System, Emergency Feedwater System, and for
~ events inside containment, the Containment Cooling System and Containment Spray System.
p-
$_A operator actions for mitigation and control of excessive steam ~
Jdemand events are directed toward the following concerns: a) ' Confirmation of automatic ESF systems actuations and proper response of; automatic plant control-systems, b) Hinimizing RCS cooldown by isolIating the cause of the event or by minimizing the amount of S/G secondary inventory available for release through the break. c) Re-establishing and maintaining RCS margin to saturation via'RCS pressure and inventory control.
~ d). Controlling feedwater to the. unaffected S/G to avoid excessive RCS cooldown rates due to cold feedwater addition.
y_
\_.)
WP84989 SECTION VII - 6.0 PAGE 4 9
,_ 6.3 Safety Functions Affected .f ') \- ' -Depending on the location and size of the excessive steam 1 demand event, the safety functions of reactivity control,.RCS inventory control,IRCS pressure control, and containment integrity may be significantly affected.
A decreasing moderator temperature caused by an excessive steam demand event will cause an addition of positive reactivity due to the negative moderator temperature coefficient. The change in RCS moderator density causes pressurizer level to decrease rapidly with a resultant decrease in pressurizer pressure. Steam line breaks or feedwater line breaks inside containment result in increased temperature, pressure, and humidity and may
'(s h result in containment isolation and containment spray actuation.
6.4 Major Parameter Response A. Reactor Power The increased energy removal rate from the:S/Gs caused by an excessive steam demand causes a reduction in RCS cold
-leg temperatures. Decreasing the moderator temperature with a negative temperature coefficient causes positive reactivity to be added to the core and results in an WP84989 SECTION VII - 6.0 PAGE.5 t
- 6
,m-h-- e.-g w ~ , - - w r n, yp.w. - --. ..m4.,- .n , .-sn- e ,
.,_ q increase in core power before a reactor trip occurs. -U Depending on the size and location of the event, the power level increase may not be detectable due to an early reactor trip. Following the reactor trip, the decreasing moderator temperature causes a reduction in shutdown margin due to the positive reactivity addition. Verification of RCS boration by the charging system or HPSI system may be required to maintain adequate shutdown margin.
6.5 RCS Temperature Due to excessive RCS heat removal, RCS T,y, will decrease below the no load value of ~ 545 F and continue to decrease until the cause of the excessive steam demand event is either terminated by MSIS actuation or the affected S/G is blown dry. Termination
-d,r~s of the cooldown of the affected RCS cold leg or stabilization of the_affected S/G pressures and level indicates that the event has ended.
After termination of the excessive steam demand event, RCS temperatures will increa=e to the saturation temperature corresponding to the setpoint pressure of the main steam safety valves on the unaffected S/G if no operator actions are taken. Actions should be'taken to stabilize RCS temperatures at a value as close to the temperatures reached during the cooldown
, - as possible and prevent the RCS from heating up. Limit-ng the RCS~heatup is extremely important if-SIAS actuation and the 8 ' f ,
V
-WP84989- SECTION VII - 6.0' PAGE 6 w
a r- r- a e-, - --.e-- -- = gr-r.-- y- w e---e , sw- e-- g .y -r-.=r-- w , - , + -- .
m addition of HPSI makeup to the RCS have occurred. This would [_
-} prevent filling the pressurizer solid due to coolant volume expansion with no letdown capabilities.
C. Pressurizer Pressure and Level Due to the shrink caused by the decrease in RCS temperature, pressurizer pressure and level will decrease rapidly at a rate corresponding to the rate of RCS temperature decrease. Although the decreases will be retarded by the automatic response of the pressurizer pressure and level control systems, the pressurizer may be emptied and a SIAS signal may be generated. I- the pressurizer is emptied, RCS pressure may decrease / rapidly to the' saturation , pressure of the RCS. hot Ing temperature. 3 Tk_) When the excess steam demand event has been terminated,' pressurizer pressure and level control should be 4 established and operator actions taken to stabilize RCS pressure at a value which provides' adequate margin to saturation but reduces the potential for a pressurized thermal shock transient. Necessary actions to limit pressurizer level increases due to thermal expansion of the RCS should be initiated.. 1,C) U WP84989 SECTION VII - 6.0 PAGE 7
- s
D. Steam Generator Pressure
- ~
Following a steam line break, the pressure in the affected steam generator will decrease due to the increase in steam flow caused by the leak and the associated decrease in RCS temperature. -The pressure in the unaffected steam generator will initially increase after the MSIS actuation and then decrease as RCS temperature decreases. 'If the steam line break has occurred downstream of the main steam isolation
. valves (MSIVs), the pressure in both steam generators should equalize after the MSIS actuation.
E. Steam Generator Level following the steam line break, the level in both steam generators will initially increase due to swell and then
, ;3 decrease rapidly as the feedwater control system will not b.
be able to keep up with steam flow. Until the HSIS actu-ation occurs, the affected steam generator will show a more pronounced response then the unaffected. If the actuation does not isolate the steam leak (eg. leak upstream of.MSIVs), the level decrease will continue until the affected S/G is boiled. dry. The level in the unaffected S/G will slowly increase .from emergency feedwater pump feed.
. o
{ ._ WP84989- SECTION VII - 6.0 PAGE 8 3- a l'
w j_q In the event of a feed line break, S/G level will decrease 3.Q ; in the affected steam generator without an initial swell while the unaffected steam generator will exhibit normal response for a reactor trip.
~6.51 Basis For MSIS Recovery Actions STEP 1: If S/G pressure is s 751 psia, verify MSIS actuation as follows:-
Verification of major automatic actions associated with a MSIS is designed to isolate the cause of the steam generator depressurization and minimize the RCS cool-
. down caused by this S/G depressurization. ?
A) MSIVs closed: C The MSIVs are closed to isolate an excessive steam demand downstream of these valves or to isolate t the affected S/G 'from the unaffected S/G. This
. limits the blowdown through-the-break to the . , remaining water inventory of one S/G, if the- . ' break is upstream of the MSIVs.
4 i WP84989- SECTION VII - 6.0 PAGE 9
'l.:
L: .
B) MMY block valves closed: (D u MFW block valves are closed to isolate feedwater-to the S/Gs. The continued addition of feedwater. would provide additional inventory to be available for blowdown through the break causing a more severe RCS cooldown and the possibility of exceeding containment building design pressure. C) SDBCS upstream atmospheric dump valves closed: Upstream atmospheric dump valves are verified closed to insure that these valves are not the i- j~ cause of the exessive steam demand event.
.b STEP 2: Secure RCPs based upon the following criteria:
A) If all 4 RCPs are running and RCS temperature is
< 500'F, secure one RCP, preferably 2P32C or 2P32D. ~
Securing a RCP at 500'F is based on core lift considerations. " C" or "D" RCP is preferred due to "A" and "B" RC1s differential pressure being used for pressurizer spray _ flow. Spray flow may be required to control RCS pressure after the transient has been terminated. WP84989- SECTION VII - 6.0 PAGE 10 Y --r-y--ajsr es -vr- .wsp-+w--t *-9 yy sy e-w v sr9-*w ,e y ,emm m*pg v- w w. 9->gyrrrw-p+ a - w# ganw-m y,o typ yy- -p.,*r ,,7*,n.v---,y=v -,g y ---
, B) If pressurizer pressure decreases to 51400 psia, ! 1 \#'
secure two RCP's (one in each loop). This step is based on the RCP termination cri-terion. Two RCP's are secured in the event that a small break LOCA has occurred concurrently with the steam line break. Leaving two RCPs running gives-the operator more control using main pressurizer spray. Additionally, it provides for continuous mixing of fluid in the reactor vessel upper head, thereby minimizing void formation. Also, mixing in the reactor vessel downcomer and lower plenum region reduces pressurized thermal
,3 ; shock concerns.
LJ - STEP 3:. Determine the location of the rupture: The operator is directed in the following steps to determine the location of the rupture so that actions may be taken to mitigate the consequences of the break. Observations of S/G parameters are made after MSIS actuation has isolated the MSIVs and FW bloch valves. The worst case (rupture upstream of MSIV's) is
. considered first.
7 P%
'WP84989 SECTION VII - 6.0 PAGE 11 =
o
. , _ , A) If the S/G pressures are unequal and one S/G pressure is still decreasing, the rupture is upstream of the MSIVs:
A comparison of steam generator pressures may be used to determine that the location of the leak is upstream of the MSIVs. The leak may be either on the main steam line, on the steam generator, on the main or emergency feedwater line downstream of the last check valves or on the steam driven emergency feedwater pump (2P7A) supply line.
- 1) If containment. parameters (pressure, temperature, humidity and sump level)-are increasing, the rupture is inside containment.
Proceed to step 6 of this tab. Increases in containment parameters provide indications that the leak location is inside containment. With a leak inside containment, isolation of the component is an unlikely' _ option,-therefore the operator is directed to step.6, which isolates EFW to the affect'ed S/G allowing it to boil dry. Leaks inside containment may result in actuation of SIAS, CCAS, CIAS and CSAS on high containment
-:%)()
pressure. WP84989 -SECTION VII - 6.0 PAGE 12
, 2) If containment parameters-(pressure, N# temperature, humidity and sump level) are not increasing, the rupture is between the MSIVs and the containment building. Proceed to step 4 of this tab.
If containment building parameters do' not show any indication that the leak is inside containment, then the leak may be located in a component or pipe between the MSIVs and the containment building penetration. No CIAS or CSAS actuation signals should occur. The operator is directed to step 4 j-s of this tab for guidance on possible ways
\,J to isolate the leak.
B) If the S/G pressures are equal and both are. still decreasing, observe 2P7A steam supply pres-sure, 2PI-0340, or. 2C16. If 2P7A supply pressure i is considerably less.than S/G pressure,'the rup- , ture may be'in the supply line to 2P7A. Proceed L to step 5 of this tab. WP84989 SECTION.VII - 6.0 PAGE 13 U_
o If both S/G pressures are decreasing and approxi-t)'- mately equal, a common flow path exists from both S/G's to the rupture, the supply line to 2P7A pro-vides a common flow path and the operator is di-rected to check EFW pump steam supply pressure in comparison to S/G pressure. Should this con-dition exist, the operator is directed to step 5 of this tab where guidance is'provided for leak isolation. c) If the S/G pressures are equal and remaining constant or increasing, the rupture is downstream of the MSIVs. Proceed to step 10 of this tab: O a
.This condition would indicate that the cause of the MSIS is probably downstream of the MSIV's,
- j. and has been isolated. The operator is directed to step 10 to verify ESFAS actuations and RCS safety functions.
x STEP 4: Attempt to isolate the upstream rupture: A) If the leak is due to the failure of a SDBCS upstream atmospheric dump valve, attempt _to isolate the valve. L.) WP84989 -SECTION VII - 6.0 PAGE 14 s W* I *
'B) Isolate the steam supply to 2P7A from the.affected
- / -}
S/G.
"A" S/G "B" S/G 2CV-1000-1 2CV-1050-2 (Panel 2C17) (Panel 2C16)
C) If the leak is through a S/G safety valve, attempt to gag the faulty valve. This step attempts to locate and isolate a leak or rupture upstream of the MSIVs. The leak may be due to a stuck open or broken SDBCS upstream atmospheric dump valve. If this is the case, the operator may be (~x able'to close the upstream isolation for the valve. A
'J leak may have occurred in the 2P-7A steam supply line between one of the steam header isolation MOVs and the check valve downstream of it. This would cause one S/G pressure to. decrease. Closing the steam header isolation Mov may isolate the leak. The leak may be due to a stuck open S/G safety valve. The safety valve may be only partially open. It may be .possible to shut the valve by installing a gaging device. ~ *~ GO TO STATEMENT *
- This statement directs the operator to step 10 of this tab if the rupture *
- has been. isolated.
,/} : *****************************************************************************. %s .
WP84989 SECTION VII - 6.0 PAGE 15
.%e
, ***************************w*************************************************
f ; GO TO STATEMENT
- This statement directs the operator to step 9 of this tab if the rupture *
- has not been isolated.
- STEP 5: . Attempt to isolate the leak in 2P7A steam supply line.
A) Close 2CV-1000-1 (2C17) AND 2CV-1050-2 (2C16): Closing 2CV-1000-1 and 2CV-1050-2 should isolate the leak in the 2P-7A steam supply line. If this action is required, the operator should realize that 2P-7A is no longer available to supply EFH.
,m
(_)- GO TO STATEMENT
- This statement directs the operator to step 10 of this tab if the rupture *
- has been isolated. *
*- GO TO STATEMENT *
- This statement directs the operator to step'9 of this tab if the rupture *
- has not been isolated. *
[ I. v. WP84989 SECTION VII - 6.0 PAGE 16 o e m - - ~ g a ~ - ~ - -, ,, --gug .,,
STEP 6: Verify that EFW is isolated to the affected S/G.
'-) ' A) Allow the affected S/G to boil dry:
If S/G pressure decreases to the MSIS setpoint, EFAS for the affected S/G will not actuate. The operator is directed to verify that EFW is not being supplied to the affected S/G even if level is low. This will allow the S/G to boil dry and minimize the RCS cooldown and possible energy release to containment. e e .e . . . e e e e e e e o e e e e o e e e e o e e e e e e e e e e e e o e e CAUTION . THE OPERATOR IS CAUTIONED TO SECURE RCP'S IF CCW IS ISOLATED TO RCPS TO e
. gy. ~e PREVENT RUNNING RCPs WITHOUT COOLING FOR THE PUMP SEALS. THIS COULD e (j
e CAUSE SEAL FAILURE AND THE POSSIBILITY OF SEAL LEAKAGE. THE 5-MINUTE *
*-PERMISSIBLE DELAY IS. BASED ON VENDOR RECOMMENDATIONS AND PRECLUDES PUMP' e *-DAMAGE. := , e e ee e e e o e e_e e o e e e e e e e o e e e e e e e e e e e e e e o e e e STEP 7: Verify the required ESFAS actuations have occurred:
A) If pressurizer pressure decreases to < 1766 psia
- OR if containment pressure increases to > 18.4
, psia, verify SIAS AND CCAS actuation as follows:
h
.Y, WP84989 SECTION VII - 6.0 PAGE 17 E! '
- 1) Two HPSI pumps running:
One HPSI pump in each HPSI header should be running to provide RCS inventory and pressure control when RCS pressure decreases to ~ 1450 psia. Additionally, when RCS pressure drops this low, HPSI will inject borated water to offset the possible positive reactivity addition due to the RCS cooldown. Normally, "A" and "B" HPSI pumps will be in Etandby and "C" HPSI pump will be in pull-to-lock. If "A" or "B" HPSI pump is-inoperable, "C" HPSI pump will be Ic placed in standby in place of that pump. q)T. There will-always be two HPSI pumps aligned for auto'_ start, one on 2A3 and one on 2A4. Upon receipt of SIAS, a HPSI pump on each bus will auto start'after a 10-second time delay.
- 2) HPSI cold leg: injection MOVs open:
'All eight'HPSI cold leg injection MOVs automatically open.upon receipt of SIAS.
These valves open to provide HPSI flow to 4 each RCS cold leg from both HPSI headers.
) i WP84989- SECTION VII - 6.0 PAGE 18
O
.;~ . 3) RWT outlet valves open:
The RWT outlet valves are normally maintained open. These valves will automatically open on SIAS if they were shut. These valves must be open to provide a suction to the HPSI pumps from the RWT.
- 4) HPSI flow when RCS pressure decreases to
< 1450 psia: .The shutoff head of a HPSI pump is ~ 1450 psia. Verification of HPSI flow -; (~k - when RCS pressure decreases below the HPSI pump shutoff head ensures proper HPSI alignment (both manual and motor operate valves).
- 5) Charging pumps running:
All available charging pumps will' auto start upon receipt = of SIAS after a 4 50-second time delay. These pumps will inject-high concentration. boric acid from' the BAM tanks into the_RCS for inventory
.and reactivity control.- .. m WP84989 SECTION VII - 6.0 PAGE 19 L:
?
;_q . 6) BAM tanks aligned to charging pump suction: '(v)
The BAM tanks will automatically provide a suction to the charging pumps upon receipt of SIAS. The BAM tank gravity feed valves open, the BAM pump to charging pump suction isolation valve opens, the VCT outlet valve closes and the BAM pumps start after a 70-second time delay.
- 7) Letdown isolated:
Letdown automatically isolates upon receipt (-$ of SIAS. This is done in order to maintain d as much RCS inventory as possible in an attempt to maintain pressurizer level.
- 8) Two SW pumps running:
The SW pumps auto start on SIAS, MSIS or EFAS. The-auto start has a 4.5-second time delay for "A" and'"C" SW pumps and a 6.0-second time delay for "B" SW pump. 1 Normally, two SW pumps are running, so unless power is temporarily lost, these two pumps (one -off of 2A3 'and one off of 2A4)
;('N; will remain running with the third pump in w;-
WP84989 SECTION VII -'6.0 PAGE 20
4 I- v- _ . _ . standby. If power is momentarily lost, or if the SW pumps weref secured, "A" and "C" pumps will normally auto start and "B" pump, with its longer time delay and interlock with "A" or "C" pump, will remain in standby. This will result in two SW pumps running, one on 2A3 and one on 2A4. . These SW pumps will provide cooling water
~
- to the ESF pumps and containment cooling fans.
- 9) Co'ntainment cooling fans running -
.f .
All four-containment cooling fans auto
.t -
start on CCAS after a 40-second. time -' delay. These fans provide containment cooling which is necessary if the r. steam / feed break is inside containment.
- . , ' 10) SW aligned to containment cooling fans
Upon receipt of CCAS, the SW to containment valves automatically open to. provide
- cooling water to the containment cooling i:
coils. v Ci [~ WP84989 SECTION-VII - 6.0 PAGE 21 I' e- ,y. .,-.a - ,.7,- -,.,1 a ,--m,y.- .. em. p , .y ..,,,,.,_s.-.y w -,v,.w-y ew-,. #%ge-%.. of7,,.r81r -
u e
- 11) containment cooling fan bypass dampers open:
t [ ).. v Upon receipt of CCAS, the containment cooling fan bypass dampers automatically open. This bypasses the normal suction air ducts and chilled water cooling coils for
' increased air flow through the SW coils. I B) If containment pressure increases to 2 23.3 psia, verify CSAS actuation as follows:
m
- 1) Containment spray pumps running:
Both containment spray pumps auto start upon ..il-1 receipt of CSAS after a 25-second time delay, These pumps will provide containment spray
, flow which may'be necessary to suppress an increase in containment pressure and , . temperature if the break is inside containment.
2)' Containment-spray; header isolation valves open: The containment spray header isolation-valves automatically open on CSAS. .These valves allow flow from the containment
;- spray' pumps into containment. ' WP84989- SECTION VII - 6.0 PAGE 22 b-
- 1
~N 3) NaOH tank outlet valves open (O
The NaOH tank outlet valves automatically open on CSAS. This provides a suction to the NaOH pumps from the NaOH tanks.
- 4) NaOH pumps running:
The NaOH pumps auto start on CSAS. The NaOH pumps do not have a time delay but they will not auto start until the NaOH tank outlet valves are open and the containment spray pumps are running. These pumps inject NaOH into the containment spray for pH control.
- 5) Containment spray flow indicated:
Verification of containment spray flow ensures proper containment spray alignment (both manual-and motor operated valves). STEP 8: . Verify containment pretsure is being maintained < 18.4 J psia:
'A) If the CSAS setpoint was reached, reset CSAS and realign the containment spray system as follows:
a WP84989- SECTION VII - 6.0 PAGE 23
- 1) Stop the NaOH pumps.
- 2) Close the NaOH tank outlet valves.
- 3) Stop the_ containment spray pumps.
- 4) Close the containment spray header isolation valves.
Containment spray should be secured as soon as possible to minimize the damage done to equipment inside containment and to minimize the
, cleanup effort required. Containment spray is secured in this manner to allow the system to remain lined up for automatic operation.
B)' If the CIAS setpoint was reached, reset CIAS and restore CCW to the RCPs as follows:
^} /
- 1) Close CCW containment return header isolation valve,.2CCW-150 (located in the upper north piping penetration room):
This valve'is closed to allow the CCW containment isolation MOVs to be reopened without restoring CCW flow to the RCPs. This prevents thermally shocking the RCP seals with a sudden restoration of cooling water flow. 'A rapid cooldown of the RCP seals may cause failure of seal components
~ and excessive seal leakage.
WP84989' SECTION VII - 6.0 PAGE 24
- 2) Open 2CV-5236-1 (2C17), 2CV-5254-2 (2C16) and 2CV-5255-1 (2C17):
These valves are closed by a CIAS and must be reopened to restore CCW to the RCPs. CAUTION STATEMENT .
- THE RCP SEALS SHOULD BE COOLED SLOWLY TO PREVENT DAMAGE TO THE .
. SEALS. .
- 3) Slowly open 2CCW-150 to establish a small amount of CCW flow to the RCP seals.
- 4) Monitor RCP controlled bleedoff and lower
'g-)s ?%
seal temperatures to establish a slow cooldown rate. 5). When the RCP seal temperatures have stabilized, fully open 2CCW-150. CCW is restored to the RCP seals to provide cooling which may-help maintain seal integrity. This will also allow RCP restart if the RCPs were secured due to CCW being isolated from containment for greater than 5 minutes. i p-v ! _WP84989 SECTION VII - 6.0 PAGE 25 i t
.-n,- .-- --c. - -
~
'd '*
GO TO STATEMENT *
- This' statement directs the operator to step 11 of this tab. This will *
- begin' verifying the safety functions.
- STEP 9: Verify that EFW is isolated to the affected S/G:
A) Allow the affected S/G to boil dry: If S/G pressure decreases to the MSIS setpoint, EFAS for the affected S/G will not actuate. The operator is directed-to verify that EFW is not being supplied to the affected S/G even if level q; is low. This will allow the S/G to boil dry and T.7 J. minimize the RCS cooldown and possibly energy release to containment. STEP 10: If pressurizer pressure' decreases to < 1766 psia, verify SIAS actuation.as follows: A) Two HPSI pumps running: One HPSI pump in each.HPSI header should be running to provide. RCS inventory and pressure
. control when RCS pressure decreases to ~ 1450 psia. Additionally, when RCS pressure- . f"N, ~
V
-WP84989 SECTION VII --6.0 PAGE 26 o
+
k-k
.-4 .;g. . ,: drops this low, HPSI will inject borated water ;") s to offset the possible positive reactivity ' addition due to the RCS cooldown. Normally, "A" and "B" HPSI pumps will be in standby and "C" HPSI pump will be in pull-to-lock. If "A" or "B" HPSI. pump is inoperable, "C" HPSI pump will .vrg j. ,5..
i be placed in standby in place of that pump. (( ' # \.un ' " , There will always be two HPSI pumps aligned for
< ', H l , auto start, one on 2A3 and one on 2A4. Upon , y '~
receipt of SIAS, a HPSI pump on each-bus will
, auto start after a 10-second time delay. , q 1 i
B) HPSI' cold leg injection HOVs open:
%- ? 1, -(w.). . 'All eight HPSI cold leg injection HOVs y f ( a C4" i, U .
automatically.open upon receipt of SIAS. These . - >s
'i' valves open to provide HPSI flow to each RCS cold leg from both'HPSI headers.
3_
< s lC) .HPSI flow when RCS pressure decreases to .s < 1450 psia:
- e. ,
t f? s The shutoff head of a HPSI pump is ~ 1450' psia. 8 ; fi Verification of HPSI flow when RCS pressure h'n decreases below the HPSI pump shutoff head ge (. h 3)n.
- p l; . ensures proper HPSI alignment (both manual and
& /'k ' motor operate valves). V 1g ap j '}';j ~ 'WP84989 Y '' SECTION VII 16.0 PAGE 27' 1e e u , f, V.; < l.
4i
,-q D) . Charging pumps running:
V All available charging pumps will auto start upon receipt of SIAS after a 50-second time delay. Ihese pumps will inject high concentration boric acid from the BAM tanks into the RCS for inventory and reactivity control. E) Letdown isolated:
. Letdown automatically isolates upon receipt of 1
SIAS. This is done'in order to maintain as much RCS inventory as possible in an attempt to maintain pressurizer level. STEP 11: Restore RCS inventory control: 1 CAUTION . -
- DO NOT OVERRIDE HPSI UNLESS THE RCS MARGIN TO SATURATION!IS 2 30*F. .
. IF'THE RCS MARGIN TO SATURATION DECREASES TO < 30*F, RE-ESTABLISH MAXIMUM . . HPSI FLOW UNTIL 2 30*F MARGIN TO SATURATION EXISTS. . . THIS CAUTION IS PROVIDED TO REMIND THE OPERATOR NOT TO THROTTLE HPSI FLOW . .IN AN ATTEMPT TO MAINTAIN PRESSURIZER LEVEL UNLESS THE RCS MARGIN TO . . SATURATION IS 2 30*F. .. . rs . --. . . ....................................
WP84989 SECTION-VII - 6.0 PAGE 28
-I e . , , - - , . - , -, - - - , ,,,,y ., gc , ,.m, ,c .,-,v -, , .-- , ,.-, ,
.im
- l NOTE l l Pressurizer level may indicate up to ~ 3% higher than actual due to l o
- 3. :l elevated containment 1 temperatures. This is due to the decrease in l 4-I density of the water in the reference legs of the pressurizer level l l transmitters. The. actual ~1evel error can be obtained from Figure 2. l A) When pressurizer level has been restored,
' maintain the desired level as follows: On a steam or feed line break or leak, the combination.of charging, possible HPSI injection and the RCS heatup will eventually restore pressurizer level.
- 1) Start /stop charging pumps as necessary:-
Since letdown is isolated, automatic control of pressurizer level is not possible. The operator will have to start and stop one or'more charging pumps to-
. maintain the desired level.
a) If pressurizer level is increasing rapidly and.RCS' temperature is still increasing, the charging pumps should
- _ !fi
<).
WP84989 SECTION VII - 6.0 PAGE 29 r b t - e--+ y 4-w-, e r-v. e-4 - -, -e iv y Tw- 1 .rw,w , r e %- e - -- v - ew-
7_ be stopped to help ensure the pressurizer
' (? / --
does not go solid: If RCS pressure decreased far enough to allow HPSI injection, or if significant voiding exists, pressurizer. level may. continue to increase to > 100%. This will mainly be due to the RCS heatup. after the cooldown has stopped. This is not expected to occur but some worst case analysis.show that it is a possi-bility. Due to this concern, the charging pumps may need to be secured-as soon as pressurizer level is restored.
- 2) Override and tnrottle HPSI cold leg injection HOVs as necessary:
~
RCS pressure should increase above-the HPSI
. pump shutoff head as the RCS heats back'up.
If RCS pressure remains below the HPSI pump shutoff head, the operator may need to
-throttle HPSI to control pressurizer-level.
T_f WP84989- SECTION VII - 6.0 PAGE 30 o
STEP 12: Restore RCS pressure control: (~~\l -
- (_ '
A) When pressurizer level has been restored, attempt to control pressurizer pressure to maintain the RCS margin to saturation > 30'F but < 200'F, per
; Figure 1.
As pressurizer level increases due to the RCS heatup, pressurizer pressure should increase. Pressurizer spray and/or pressurizer heaters
~ should be used to maintain the desired RCS margin-
[ t'o saturation to ensure adequate RCS subcooling and to prevent a possible' PTS problem.
. p,)" -t
- 1) If RCPs are running, operate main spray valve (s) to limit die pressur'e increase:
If the RCPs are running, normal pressurizer spray is the preferred method of limiting RCS pressure. This is because it causes lessoof a thermal transient on the spray
' nozzle.
SE
- 2) Verify 'a charging pump running AND operate
~
auxiliary spray to limit the pressure increase 4 j WP84989 SECTION VII - 6.0 PAGE 31 I " n , , .-
- . . , , , -- + , - -n, - . s. , - , - . - - - , , - , c, . , , ,, r,- ,
,_q . If RCPs are not running, auxiliary spray J 1 should be used if pressure must be limited.
a) If the pressurizer and charging water temperature difference is 2 200'F, complete Attachment "A" of OP 2103.05 for each spraying cycle: This step ensures Technical Specification 5.7.1 is satisfied. SE
- 3) Verify pressurizer level is > 29% and
- ("T- restore pressurizer heaters to operation to N J:
increase pressure: If pressurizer pressure is low, once level is above the heater cutout level of 29%, the' pressurizer heaters can be placed in operation to increase pressure. B) While maintaining the RCS per Figure 1, restore 3-pressurizer pressure to 21800 psia but s 2300 psia: e
- xJ.
.WP84989 SECTION VII - 6.0 PAGE 32
r Pressurizer pressure is restored to 2 1800 psia ['y k/ to allow SIAS to be reset. Pressure is limited to s 2300 psia to avoid challenging the pressurizer safety valves. C) ;If the SIAS setpoint was reached, reset SIAS and realign, systems as follows:
- 1) Restore RCP controlled bleedoff to the VCT by opening 2CV-4846-1 (2C17) and 2CV-4847-2 (2C16):
RCP controlled bleedoff is restored to the
- 1 - VCT sto prevent overfilling or
~
overpressurizing the Quench Tank.
- 2) Verify a charging pump is running and place the' letdown system in service:
The letdown system is placed in. service.to allow pressurizer level to befreduced, if necessary, and to allow automatic controlfof pressurizer level. A charging pump must be running to provide regenerative heat
-exchanger cooling of the letdown. With 'SIAS. reset,. equipment that is running,-such -p. . %,1 WP84989' SECTION VII - 6.0 PAGE 33 w.
a
, s ) .
(, ~\. as HPSI pumps, LPSI pumps, EDGs, etc., can be secured normally as time permits and can remain aligned for automatic operation. Also, the SW valves with !! SIS and SIAS signals to them can now be operated when the MSIS is reset. The operator needs to be aware that letdown heat exchanger outlet temperature may be abnormally high due to no SW to CCW, but that letdown can be used to limit pressurizer level if the ion exchangers are bypassed on high temperature. STEP 13:. Establish RCS heat removal capability: A) Allow RCS temperature and S/G pressure (s) to increase: _7-r-<
;, After the cooldown has been terminated by ether F . MSIV closure or the affected S/G boiling dry, RCS temperature will increase due to the decay 4
heat being generated:in the core-and RCP heat c < input, if running. Since the MSIS closes the SDBCS upstream atmospheric dump valves and the 1 MSIVs, no effective means of- RCS . heat removal is available. The SDBCS upstream atmospheric dump valves can be opened manually but if the leak i.s in the MSIV room, access may not be possible.
-The operator has no choice but to allow RCS' b
WP84989 SECTION VII - 6.0 PAGE 34
o q ;~s ;
- c temperature to increase until both S/G pressures-are above the MSIS setpoint or until the S/G safety valves on the' unaffected S/G control RCS temperature.
B) If possible, reset MSIS and perform the following: It is desirable to reset MSIS so MSIS actuated equipment may be placed in service to aid in stabilization of RCS and secondary plant parameters. The ability to reset MSIS will depend on the location of.the leak or break. If the leak or break was isolated by the closure of the MSIVs, .r-s... S/G pressures should be approximately. equal and i %.) ' increasing due-to the RCS heatup. MSIS can be reset when S/G~ pressures are above the actuation setpoint. This will allow the upstream atmospheric dump valves to be used for RCS temperature control.
- 1) Restore SW to the CCW heat exchangers:
This provides cooling water for the CCW system which cools the RCPs, instrument air compressors, letdown heat exchanger and
-other desired components. CCW system K
- . ~s WP84989 SECTION VII - 6.0 PAGE 35 x.
o
temperature changes should be made slowly to U-prevent RCP seal temperature transients which
, may cause seal pressure oscillations.
- 2) Reset SDBCS upstream atmospheric dump valves:-
When MSIS is reset, the MSIS signals to the upstream atmospheric dump valves can be reset. Regaining control of upstream atmospheric dump valves gives the operator
-the ability to control RCS temperature and , S/G pressure. ~ /N h< t. )
3)- Limit RCS heatup rate to < 100*F/hr: ANO-2 Tech. Spec. 3.4.9.1 limits RCS heatup rate to 100*F/hr.
- 4) If necessary, limit RCS temperature increase to maintain control of pressurizer level and
- pressure
, o If RCS pressure decreased far enough to , allow HPSI injection, pressurizer level may be too high when the RCS heats back up. .p).
LWP84989 SECTION VII - 6.0 PAGE 36 r w - - , e g~.+ y _.m . -- ,-, _m..,, --- v.. . . , , - c.v .,4,-. --.-- - -. --.-- ,y ,,- , y,--.. ,-y,.,.-o-w. w,w,- , - . - - ~
.m 1 ^ The letdown system should be in service by
' t(((f now but RCS temperature may still need to be limited to maintain an acceptable pressurizer level. 'If MSIS is reset, the operator can monitor pressurizer level and pressure and operate the SDBCS upstream i atmospheric dump valves to limit the heatup to limit the< level and pressure increase.
, 5) If location of rupture allows, equalize around and open the MSIVs: ~ i;.
If the leak or rupture can be isolated, the MSIVs can be opened. This will provide the ' 1. operator with the use of the-SDBCS downstream atmospheric dump valves and bypass valves. e
'6) If MSIVs are opened, operate SDBCS bypass :
valves to control RCS temperature:
) Preference should be given to use of.the SDBCS bypass valves, if' condenser and valve-status permit. Use of the bypass valves .. prevents loss of condensate water to e >
atmosphere .
;J ~ --
WP84989 SECTION VII - 6.0 PAGE 37
. p I
. - - . - . - .-. .~
J ' C) If MSIS cannot be reset and RC/ operation is t)
^--
to be continued, manually align SW to the CCW heat exchangers: If the leak or break could not be isolated, the affected S/G pressure will not increase above the MSIS setpoint. In this case, MSIS will not be able to be reset. 'SW should be manually aligned.to the CCW heat exchangers. This ~ includes <d to and from the heat exchangers. This needs to be done to maintain CCW 4 temperature so CCW can effectively cool.the RCP seals =and letdown heat exchanger. In order to reopen these valves, power must be removed from 2CV-1530-1 (53G3) and 2CV-1543-1 (54H2) or 2CV-1531-2 (64F1) and 2CV-1542-2 (63J3).
, D) If HSIS cannot be reset, attempt to control S/G pressure below the S/G safety valve setpoint, as follows's l
If MSIS cannot be reset, the RCS will heatup to the S/G safety valve setpoint. Since continuous lifting of the S/G safety valve (s) increases the
- possibility of failure, it is desirable to establish some other means of RCS heat removal.
s,_
;WP84989- SECTION VII - 6.0 PAGE 38 o
g_ -
- 1) Locally operate a SDBCS upstream atmospheric
' '- b' . .
dump valve If possible, a SDBCS upstream atmospheric dump valve should be operated manually to maintain S/G pressure below the safety valve setpoint.
- 2) Run 2P-7A if rupture location allows:
If 2P-7A is running or can be run, this is a means of removing RCS heat. Even if this method does not completely stop the S/G safeties being lifted, it should reduce it considerably. 3)- If the rupture location allows, open MSIV bypass valve (s) and dump steam to the condenser or atmosphere: MSIVs will have been closed by MSIS actuation, however, MSIV bypass valves provide a 2-inch flowpath to downstream dumps and turbine bypass valves. These valves receive no.MSIS signal, so they may be operated normally from
'the control room. Use of SDBCS bypass valves /^% reduces secondary inventory loss. .L) - ~tfP84989 SECTION iI - 6.0 PAGE'39 w- ._:_.____--___--------_----
A)- '.Three conditions are identified as RCS temper-
~ '~
ature and pressure situations where an engineering evaluation of reactor vessel thermal stresses is required. .They are based on (1) RCS lower limit (500*F) below which the reactor vessel and/or its components may possibly experience thermal stresses based on engineering analysis, (2) and RCS cool - down rate (100*F/ hour) in violation of Technical Specifications, (3) RCS pressure and temperature coordinates outside an allowable operating band 4 as depicted in a graph based on engineering pres-sure/ temperature calculations for the RCS. Should any of these conditions be present, plant-g-} management should be requested to provide an v engineering evaluation to determine the effects on the reactor vessel. Based on the results of the evaluation for pressurized thermal shock, plant management should provide directions for return to hot standby or an RCS cooldown. A WP84989, SECTION VII - 6.0 PAGE 40 e
.. u
- r; - -
2
. ~. - -
E). IF possible, maintain Tave >-540*F but < 555*F: p; r - - ( s S. 1Tave-in this band assures the operator of adequate RCS heat: removal via the S/G's. The upper limit.
' of 555*F is. chosen due to its saturation pressure- ~
Lbeing le'ss than the lowest S/G safety setpoint (1078 psig). The lower limit of 540*F is based on normal values of Tave. A temperature of less than 540*F indicates overcooling which can be caused by overfeeding or oversteaming. Ll NOTE 'l ll S/G levels'may indicate up to - 5% higher than actual due to elevated l 4 _.l containment' temperatures.~ This is due to the decrease-in density of the. l
~ ~ 'I water-in the= reference legs of the S/G-level transmitters. The actual l 'il level error can'be obtained from Figure 1. l F) : Verify 1that EFW is maintaining the intact S/G level (s) ) 10% but < 90%:
_E With S/G 1evel in the desired band,- the operator is assured of an _ available heat' sink. The lower limit of 10% (narrow range) ensures enough of'the.
' tube bundle is covered to provide adequate heat ' transfer-from the RCS to the secondary.: The upper ,
limit of 90% (narrow' range) establishes the upper -
>WP84989 SECTION VII - 6'0- . PAGE 41 ;n 4 .g N
,_ control boundary. Level above this value indicates
!'"') - a feedwater control problem which, if left'un-checked, could result in S/G overfill. GO TO STATEMENT *
~* This statement directs the operator to perform the " Inadequate Core Cooling"*
- tab in conjunction with this tab if a complete loss of feed is experienced '*
-* with no immediate recovery indicated. The " Inadequate Core Cooling" tab *-
- will provide guidance for re-establishing some means of S/G feed and *
- guidance for core cooling if feed cannot be restored. The " Inadequate Core *
- Cooling" tab is done in conjunction with tab so that the operator can *
- continue with the MSIS recovery while actions are being taken to restore
- A
- feedwater. *
'O , STEP 14: Verify core heat removal: This safety function addresses circulating cooling fluid through the core to remove decay heat. Core heat removal is verified by verifying either RCP's running (prefered method - forced flow) or natural circulation, and RCS margin to saturation > 30 (subcooled fluid). i/
~WP84989 SECTION VII - 6.0 PAGE 42 i
D .
.N r 7
A) . Verify at least one RCP in each loop is running: RCP operation is desired to ensure continued forced circulation of coolant through the core, to provide the capability for normal pressurizer s spray flow and to provide for forced cooldown of the isolated S/G. .This action enhances the strategy to obtain an uncomplicated cooldown -
, during a recovery from an excessive steam demand event. Only one RCP in each loop needs to be-operated in an effort to minimize heat input into the RCS. .B) IF RCP's are not running:
- 1) Verify RCP restart criteria are satisfied per Appendix H, AND
' 2) . Attempt to start one RCP-in a loop with an operable spray valve, THEN Attempt'to start one RCP in the opposite loop.
In these steps, the operator is directed to attempt to restart RCPs to enhance core cooling. h WP84989.. SECTION VII - 6.0 PAGE 43 u__ -
,% C) If RCPs cannot be started, verify natural cir-I' culation as follows:
Should RCPs not be available, natural circulation may be utilized for core cooling. Guidance is given in the following steps to verify natural circulation has been established.
- 1) Hot leg temperatures (T ) have stabilized h
or are slowly decreasing:
- 2) Cold leg temperatures (T ) have stabilized or are slowly decreasing:
Hot leg temperatures (T h
) an cold leg temperatures (Tc ) should stabilize and may slowly decrease. This indicates that the AT has increased enough to establish the required flow to remove the decay heat being -
produced. These indications of T hand T, are assuming a relatively constant S/G pressure is being maintained. v,1 WP84989 SECTION VII - 6.0 .PAGE 44 p-
E. t: - _,._ 3) _ RCS AT h(T - T ) is less than 50*F: Q), RCS AT (T h - T ) should be less than 50'F. Actual testing and experience have shown that a AT > 50*F is abnormal and may indicate that natural circulation flow rate is de-graded.
- 4) No abnormal difference between core exit thermocouples and hot leg RTDs:
No abnormal difference between core exit thermocouples and hot leg temperatures should e exist. If core exit thermocouple temperatures increase much above T , natural circulation h flow may be insufficient.
- 5) Continous demand for EFW flow-to maintain constant steam generator level (s):
- 6) Continuous demand for the operation of the SDBCS valvels) or S/G safety valves to maintain a constant S/G pressure s
( WP84989 SECTION VII - 6.0 PAGE 45 a
.-t. ,_$ If the S/Gs are functioning as a heat sink for the RCS, there will be steam flow from at least one location. If steam is released 'from the S/Gs, feedwater must be added to maintain level.
D) Verify RCS margin to saturation 1 30*F: Verifying that the RCS margin to saturation is 1 30*F ensures that the reactor coolant is maintained subcooled. Circulating a subcooled fluid is the preferred method of removing core decay heat. i l3 y STEP 15: Attempt to place the plant in a normal lineup as follows: This step attempts to return the plant to a normal I Hot Standby mode to allow extended Mode 3 operations or to allow a normal cooldown to be performed. A) If possible, locate and isolate the leak Locating and isolating the leak may allow the MSIVs to be opened if the leak was downstream-and may allow restoration of the affected S/G if the leak was upstream of the MSIVs. l ]) WP84989 SECTION VII 6.0 PAGE 46
\ '
B) If MSIS was not reset, with the help of the I&C
. (N Department, reset MSIS:
Resetting MSIS will allow the MSIVs to be opened
-and will allow MSIS actuated equipment, such as condensate pumps, to be operated.
- 1) Ensure EFW remains isolated to the affected S/G:
When I&C resets MSIS, EFAS for the affected S/G may actuate. The operator must override the EFAS to the affected S/Gs EFW block valves
^q -and close these valves. %) _
s C) Equalize around and open the MSIV(s) on the intact S/G(s), if not open already: This step makes available the downstream dumps and turbine bypass valves. Use of the bypass valves is preferred for conservation of condensate water. 4 I Q,5 WP849891 SECTION VII - 6.0 ~ PAGE 47
- i ,
~ D) Verify gland sealing steam to the main turbine and MFP turbines:
Sealing steam is necessary to maintain a vacuum in the main condenser. It also prevents turbine damage due to air inleakage. E) Restore vacuum in the main condenser if it was lost: Condenser vacuum is required for the operation
-of the turbine bypass valves which is the-preferred RCS cooldewn path due to conservation of condensate water.
F) Restart a condensate pump and establish short path recirc: This is done to make S/U B/D DI effluent available to the EFW pump suction.' G) If possible, align EFW pump suction to the S/U B/D DI effluent by opening 2EFW-0706: This step is done to conserve CST inventory. WP84989' SECTION VII - 6.0 PAGE 48 s
r_m .- H) -Align charging pcmp suction to VCT. Maintain
'f G h- l adequate VCT level:
This step prevents further boration of the RCS. I) Verify main turbine and MFP turbines on jacking gears: Placing turbines on jacking gears prevents rotor bowing. J) If possible control RCS temperatures with SDBCS bypass valves: (3 L) Using bypass. valves conserves condensate inven-tory. In addition, the 5% bypass valve provides better control due to its size.- The SDBCS. may be placed in auto, if desired. K) Verify required SDM: This step ensures compliance with Tech. Spec. 3.1.1.1 for the applicable operating mode. t_- WP84989 SECTION VII - 6.0 PAGE 49 o _ _m
-: 1 ~b a ~ ~ .
L) Perfonm section 6.0 of OP 2102.06, . Reactor Trip nd', = -. ' Recovery Procedure Performance of this step ensures proper notifi-cations have been made. Plant conditions'are analyzed and notification required by the ANO Emergency Plan are made. M) Obtain a RCS iodine sample
.This step ensures compliance with Tech. Spec. ~
3.4.8. c ' STEP 16: :As directed, maintain Mode.3 conditions per OP.2102.02 OR establish Mode 5 conditions per OP 2102.10: t. The severity of the transient and the size and
-location of the leak should be evaluated to determine the proper actions required for full plant recovery.
t b I O. . WP84989 .SECTION VII - 6.0' PAGE 50
= .)
7.0 SIAS RECOVERY ACTIONS i D 7.1 Operational-Goal
-The operational goal of the SIAS recovery tab is to minimize plant damage and maintain public safety. This is accomplished >
by ensuring core cooling and containment integrity to minimize the release of radioactive material during a LOCA. 7.2' Description of a LOCA A loss of coolant accident (LOCA) is caused by a break in the RCS pressure boundary. The break can be.as large as a double-ended break of the hot leg or as small as a break which results in a loss of coolant at a rate that is just in excess " of the available charging capacity. Opening the ECCS vent, a (~/ stuck open pressurizer safety valve and a letdown line rupture are examples that will also result in a loss of RCS inventory. While a break is usually referred to as the cause of a LOCA, situations like the above may also result in LOCA conditions. It is generally assumed that a leak that is greater than 3/8 inch in diameter will exceed charging capacity. Small and large break LOCAs differ in their means of post-LOCA RCS heat removal. For a large break, the only means of RCS heat removal necessary, both short and long-term, is safety injection flow into the RCS and out the break with core boiloff. For small breaks, heat removal via the flow out the (q
.v / -WP84989 SECTION VII - 7.0 PAGE 1 L __ ~
, . . break is not sufficient to provide cooling, therefore S/G heat s removal is required.
A LOCA is characterized by an initial decrease in RCS pressure and inventory. Subsequent RCS inventory and pressure response depends on the size of the break. For large breaks, an increase in containment temperature and pressure occurs relatively soon after the LOCA. A small LOCA may not be detectable on containment temperature and pressure instruments in the short-term. 7.3 Safety Functions Affected A LOCA primarily affects RCS inventory and pressure control, s and RCS and core heat removal. To a lesser degree, reactivity . I ) control and containment integrity are also affected. RCS inventory control is initially lost since the break flow rate exceeds the available charging pump capacity of the plant. For small breaks, RCS inventory control is regained via injection from the HPSI and charging pumps. It is maintained in the long-term by HPSI injection. For large breaks, inventory control is regained through the injection of water into the RCS by the SITS and the LPSI pumps. It is maintained in the long-term through the recirculation of sump water through the RCS by the HPSI pumps. Note that for large breaks, the RCS may not totakly refill and pressurizer level may not be t l WP84989 SECTION VII - 7.0 PAGE 2 a w.
regained. For the large break, injection is required 7 . V* ' continually to make up for the loss out the break and prevent boron precipitation. RCS pressure control is initially lost since the RCS depressurizes as a result of the loss of inventory out the break. For large breaks, the RCS depressurizes in 10 seconds to 3 minutes to. pressures typically belov 300 psia. In the case of the largest breaks, the RCS pressure will reach equilibrium with containment pressure and will be nearly equal to that pressure. Because of the size of the break,-RCS pressure control is never regained. The RCS remains depressurized. For small breaks, the RCS 'depressurizes during the short-term (10 to 30 minutes) to an equalibrium condition with the S/Gs. O It ' then continues to.depressurize as the S/G tubes are voided or the S/Gs are cooled down. Pressure control is regained when the safety injection system refills the RCS and pressurizer level is regained.
/
There are two paths initially available for RCS heat removal r s, heat transfer via the S/Gs and heat transfer via the fluid flow out the break. Large break LOCAs have sufficient fluid flowing yy out the break to provide adequate heat removal without relying
~
on 5/Gs. 'Small break LOCAs do not have sufficient fluid eg ' flowing out the break to provide adequate heat remeval . Dh" /1 Therefore, S/G heat removal is required in addition to break (D l
.V- ;c l ~WP84989 .SECTION VII - 7.0 '
PAGE 3 e ( t I fli. _ . . _ . . . - _ . _ . - - - - - -
I flow for adequate heat removal. The large break LOCA heat removal process is not complex. For cold leg breaks, the ECCS , - refills the reactor vessel and provides only enough fluid to the core to match boil off. The excess injected fluid spills out the cold leg break. The steam from core boil off passes out the hot leg and through the S/Gs on its way out the cold leg break. For the hot leg break the injected water builds up in-the cold legs and provides the core with water for boil off
-heat removal and some single phase cooling. In the long-term, heat. removal is provided by simultaneous hot and cold leg injection. This process provides heat removal for either hot or cold leg large break LOCAs while providing the added benefit of ensuring adequate flushing of the reactor vessel to avoid buildup of non-volatile materials produced in the boil off q(J _
cooling process. The small break LOCA heat removal process is.more complex. In the short-term, after the RCPs are tripped, core heat removal is maintained by natural circulation. Since the break is not' large enough to adequately remove the heat, heat. removal via the.5/Gs is required. This requres that feedwater (either MFW
.or EFW) be maintained to the S/Gs.
L.) l WP84989 SECTION.VII - 7.0 PAGE 4 l 7 L
.y s -
[
.p\ - . . t v. -
3
)
Ty 7.4 Major Parameter Response
*)
, i 3 x A. ' Reactor Power
}g The re ctor will trip on DNBR/LPD or low pressurizer ,g. -.t pressure. Reactor power will be decreasing as a result of the reactor trip. Additional negative reactivity .[
insertion will be provided by moderator voiding and boron addition by the charging pumps and safety injection pumps. B. RCS Temperature
. n([( > , Following the reactor trip, RCS temperature initially s c i -
m e. / - decreases for all size LOCAs due to the reduction in heat
\\' W
( g: input into the RCS and due to the heat removed out the s ..
- w. oc..
4 break and by the S/Gs.
,i: ( . C. Pressdrizer Pressure .r.
n .J / Pressurizer pressure decreases due to the lowering u, pressurizer level or due to a steam space leak. The N , e lowering level.may'be due to leakage from a break and the j- .Q- ,/ t reduced RCS temperature. M t.i , Pressurizer Level g D . '. j;;Qf3g' q ! .L -
- Pressurizer level may decrease or increase. For breaks
~
@ not located.in the pressurizer, the pressurizer may empty and, depending on.the size of the break, not refill during-the course of'the accident. Breaks located in the o - pressurizer may lead to increased pressurizer level since
. water from the hot leg flows into the pressurizer surge line while significant voiding of the RCS is occurring.
If there is a break on or near the pressurizer level r
.V' sV)
WP84989. ' SECTION VII -'7.0 PAGE 5-e a e
, instruments, this may cause this instrument to be grossly 'd . inaccurate and misrepresent pressurizer level.
E. S/G Pressure S/G pressure should increase in the short-term due to the reduction in steam flow and the SDBCS controlling S/G pressure at the no load setpoint. F. S/G Level S/G 1evel will decrease due to shrink and then be restored by the MFW or EFW systems. 7.5 Bases for SIAS Recovery Actions STEP 1: Secure RCPs based upon the following criteria: A) If pressurizer pressure decreases to s 1400 psia,. secure two RCPs (one in each loop): Monitor RCS mat gin to saturation throughout this g- B) k tab. If RCS margin to saturation decreases to-
< 30'F, secure the remaining RCPs:
This step satisfies the requirement to secure RCPs on a LOCA. On LOCAs of 0.02 ft2 to 0.1 ft2 in size, all RCPs need to be secured to minimize the-loss of inventory from a hot leej break. Pressurizer pressure will decrease below 1400 psia and the RCS will go to
~
saturated conditions on a LOCA of this size. This step ensures that the RCPs are secured on this size LOCA.~ Additionally, this step prevents the undesirable condition of RCPs running with'the RCS in saturated conditions. d/^ WP84989, SECTION VII - 7.0 PAGE 6
STEP 2: Verify the required ESFAS actuations have occurred: , This step provides a list of the ESFAS actuations, their setpoints and the-major equipment that must be verified to ensure core cooling and containment i integrity. Since the amount of equipment actuated by the various actuation signals is so large, only a summary of the more vital equipment that must be running or positioned is provided in this step. As time permits, the operator may reference the provided appendixes for a more detailed verification. A) If pressurizer pressure decreases to s 1766 psia
/- or containment pressure increases to 2 18.4 psia, Q:
verify SIAS and CCAS as follows:
- 1) HPSI:
The function of HPSI is to inject borated water into the RCS. This is required for h small break inventory, control and for large break-long-term cooling which requires a
. level to be maintained in the reactor vessel for core boiloff. . ,rm. %4 . , WP84989 SECTION VII - 7.0 PAGE'7 i
I t -
I,
,_ a) Two HPSI pumps running:
(,) - Normally, "A" and "B" HPSI pumps will be in standby and "C"'HPSI pump will' be in pull-to-lock. If "A" or "B" HPSI pump is inoperable, "C" HPSI pump will be placed in standby in place of that pump. There will always be two HPSI pumps aligned for auto start, one on 2A3 and one on 2A4. Upon receipt of SIAS,'a HPSI pump on each bus will auto start providing flow to both HPSI headers. The HPSI pumps-have a
._(^T- 10-second time delay on auto start.
- <Q b) HPSI cold leg injection HOVs opens
- All eigh't HPSI cold' leg injection HOVs automatically open upon receipt of SIAS. These valves open to provide HPSI flow to each RCS cold leg from
~both HPSI headers. .: r;- . -(
WP84989 SECTION VII - 7.0' PAGE 8L 6
l
~ < c) RWT outlet valves open:
The RWT outlet valves are normally maintained open. These valves will automatically open on SIAS if they 4 were shut. These valves must be open to provide a suction to the HPSI, LPSI and containment spray pumps from the RWT. d) HPSI flow when RCS pressure decreases to < 1450 psia r - The shutoff head of a HPSI pump is ~ 1450 q psia. Verification of HPSI flow when RCS. pressure decreases below the HPSI pump shutoff head ensures proper HPSI alignment-(both manual ~and motor operate valves). d
+ ~ ..W v \ ~ ; WP84989' .SECTION VII - 7.0- PAGE 9 +
. -q 2) LPSI: .%)
The function of LPSI is to inject large quantities of borated water into the RCS during a large break. The LPSI pumps pro-vide sufficient flow to cover and cool the core, limiting fuel cladding temperature and metal-water reaction. s a) LPSI pumps running: V Both LPSI pumps will auto start upon receipt of SIAS. The LPSI pumps have (~ a 15-second time delay-on auto start. t]' - b) LPSI injection MOVs open:
.All four LPSI injection MOVs automatically. -open upon receipt of' SIAS. .' These valves open to' provide LPSI flow to each RCS cold leg from the common LPSI' discharge header.
2
,- i J .- 'WP84989 SECTION VII -'7.0 PAGE 10 I
d
me c) LPSI flow when RCS pressure decreases-
,Om_ =
to < 180 psia: The shutoff head of a LPSI pump is
~ 180 psia. Verification of LPSI flow-when RCS pressure decreeses below the LPSI pump shutoff head ensures proper LPSI alignment (both manual and - control valves). >
- 3) CVCS:
The CVCS is actuated to' supply highly
S concentrated boric acid to the RCS via the ? :
charging pumps and to isolate letdown. a) _ Charging pumps running: - ,e ? All available ' charging pumps will' auto - start'upon receipt of SIAS. ..Normally,. I all three charging pumps'are maintained-available but only'two are ' required to be'available. There will:always be at least.two charging pumps aligned for
~
auto' start, one on the red bus.and one . ,
-on:the green bus. LThe charging pumps .WP84989 .SECTION VII - 7.0 PAGE 11 1 'g:
o
- , - + .-,em- 4 .= -ys - - , , --- ,,w-am.,,,,- g -.,y-g,-w---3,--,wwe -wv- -"~-p a 'W # w - W e v- =W grWTy *--*wwv v'm yr""-t--'W F-
- g ~
1
- s. will inject the high concentration
'^
boric acid from the BAM tanks into the RCS via the normal charging injection lines. The charging pumps have a 4 50-second time delay on auto start.
-b) BAM tanks aligned to charging pump suction The BAM tanks will automatically provide a suction to the, charging pumps upon receipt of SIAS. The BAM tank gravity feed valves open, the BAM pump to ^T charging pump suction. isolation valve (J -
opens, the VCT outlet valve closes and the BAM pumps start'after a 70-second
~
time dealy. c) Letdown isolated:
, Letdown automatically isolates upon receipt'of SIAS. This:is to provide isolation of a possible cause.of the LOCA'and to retain as much RCS inven'-- , _ tory as possible.
s
-WP84989 SECTION VII - 7.0 PAGE 12
- 4) RCS sample isolation valves closed:
(f-<) . 3z The RCS sample isolation valves automatically close on SIAS. This provides isolation of a possible cause of the LOCA.
- 5) Two SW pumps running:
The SW pumps auto start on SIAS. The auto start has a 4.S second time delay for "A" and "C" SW pumps and a 6.0 second time delay for "B",SW pump. Normally, two.SW pumps are running,.so unless power is tem-
/~i % )'
pararily lost, these two pumps (one off of 2A3 and one off of 2A4) will. remain running with the third pump in standby. .If power is momentarily lost, or if the SW pumps were-secured, "A" and "C" pumps.will normally-auto start and "B" pump, with its longer time delay and interlock with "A" or "C" pump, will remain in standby. This will result in two SW pumps running, one on 2A3.
~
and=one,on 2A4. These SW pumps will provide cooling water to the ESF pumps and
' containment cooling fans. , +
I(~')s
~ 'WP849891 SECTION VII - 7.0 PAGE 13 + ., b
- 6) Containment cooling:
v. The function of the containment cooling system is to maintain containment pressure
, and temperature below the design values.
a) Containment cooling fans running: All four containment cooling fans auto start on CCAS after a 40-second time' delay. b) Containment cooling fan bypass dampers open: Upon receipt of CCAS;'the containment cooling fan bypass dampers.. automatically open. This bypasses the normal suction air ducts and chilled water cooling coils for increased air flow through1 the SW coils.
-m '^. ~
WP84989 SECTION VII - 7.0 PAGE 14 s k:_
r
. ,x . . c) SW aligned to containment cooling fans:
V .; Upon receipt of CCAS, the SW to contain-ment valves automatically open to provide cooling water to the containment cooling t Coils. B) If containment pressure increases to 218.4 psia, verify CIAS as follows: The function of C7AS is to isolate the containment penetrations not used during the LOCA in order to minimizeLthe amount of radioactive material
~N released from containment.
(d .-
- 1) In the.CIAS sections of 2C16 and 2C17, verify valve position indications correspond to their~1abel plate color.-
This method of verification is used because the CIAS equipment is well grouped on 2C16 and 2C17 and all of the containment isolation' valves actuate closed. The containment isolation valves automatically close on.CIAS so the operator verifies the
. green closed indication for these valves is lit. 'This corresponds to their green label l plates.
WP84989 SECTION VII - 7.0 PAGE.15 s e
,- C) If containment pressure increases to 2 23.3 psia, s
L verify CSAS as follows: The function of the containment spray system is to spray borated water into containment in order to suppress any resultant increase in containment pressure and temperature. The system also functions to introduce NaOH into the spray to rapidly reduce fission product iodine concentration in the containment atmosphere and to adjust the pH.
- 1) Containment spray pumps running:
. (q R
Both containment spray pumps will auto start upon receipt of CSAS after a 25-second time delay.
- 2) Containment spray hea' der isolation valves open:
l' The_ containment spray header isolation valves
, automatically open on CSAS. These valves -allow flow from the containment spray pumps into containment. . \_/ .
WP84989_ .SECTION VII - 7.0 PAGE 16 l r
l j l
- 3) NaOH tank outlet valves open:
The NaOH tank outlet valves automatically 1 open on CSAS. This provides a suction to l l the NaOH pumps from the NaOH tanks.
- 4) _ NaOH pumps running:
The NaOH pumps auto start on CSAS. The NaOH pumps do not have a time delay but they will not auto start until the NaOH tank outlet valves are-open and the con-tainment spray pumps are^ running. These
; -pumps inject NaOH into the containment spray for pH control and iodine removal.
- 5) Containment spray flow indicated:
o ~ Verification of containment spray. flow ensures properLcontainment spray alignment:
-j
- (both manual and motor operated valves).
%b i,g, ,
Y'
, WP84989; 'SECTION VII 7.0 PAGE 17 u
l l 1 l
,a, D) If S/G level decreases to s 46.7%, verify EFAS Y_ \
as follows: ' The function of EFAS is to restore and maintain S/G levels to ensure.the S/Gs are available to remove heat.from the RCS. 1)' EFW pumps running: Both EFW pumps' auto start'on EFAS. 2CV-0340/2SV-0205 open to start 2P-7A-with no time delay. 2P-7B starts after a 90-second time delay.
-fT V
- 2) EFW flow indicated and S/G levels being restored or maintained:-
Verification of EFW flows ensures proper EFW alignment (both manual-and motor operated valves). . Verifying that S/G
- levels are being restored or maintained ensures sufficient flow is present.
4 r)_
'WP84989 SECTION VII -- 7.0 PAGE'18 e
f v - w yr,.,-- -yy, , ~ , - - -e 4,~m.- , ee -**w*n-a = -v e- -w - re w--
- t
);s .E) As time permits, a detailed ESFAS actuation N,)! l verification may be performed per Appendix "A" through "E":
1 These appendixes provide a complete list of all ; l components actuated on the various signals. This verification may help ensure that all required equipment has actuated. The use of these appendixes prevents relying on operator memory and/or control board layout and labeling for proper actuation verification. STEP 3: Verify adequate core heat removal: During a LOCA, core heat removal is considered to be adequate as long as the core is maintained-covered and either flow out of the break or the S/Gs along with flow out of the break is removing the heat. Monitor core exit thermocouple temperatures _A)
, per Figure 2:
CET temperatures should remain in_ Region 1 (including.the-saturation line) of' Figure 2. This should indicate that the core is covered Land the RCS is either subcooled or saturated.
-(v )'
WP84989 SECTION VII - 7.0 PAGE 19
CET temperatures in Region 2 indicates ay > superheated conditions at the core exit which indicates the core is not completely covered. Core decay heat is removed by flow out of the break and/or by natural circulation via the S/Gs. Natural circulation may be two phase or single phase. Verifying CET temperatures in Region 1 ensures a combination of the'above is cooling the core. GO TO STATEMENT
'* This statementLdirects the operator to perform the " Inadequate Core Cooling"*
- tab in conjunction with this tab if CET temperatures enter Region 2 of f ("' -
- Figure 2. This tab will provide guidance to the operator for increasing
- b
- core heat removal and ensuring .the core is covered.
- B) If RCPs are not running, one RCP in each loop.
may be restarted when the RCP -restart criteria of Appendix H are satisfied: This step is directed _at the small. break LOCA where RCS inventory and pressure control are regained. In this case, the S/Gs are the primary means of RCS heat removal. RCP restart is desired to aid in the elimination of voiding : and to provide'for a more controlled cooldown. L.) WP84989 SECTION VII - 7.0 PAGE 20 i }/
4 A
. .. Only two RCPs are restarted to minimize the heat ~
input.into the RCS and because only one RCP per S/G is necessary for proper RCS heat removal. The first RCP started should be a RCP with an operable spray valve to enhance the ability to control RCS pressure. STEP 4: Verify containment integrity is being maintained as follows: This step verifies that the containment heat removal systems are functioning to maintain containment
- , pressure and temperature within their design limits.
RIt also ensures proper monitoring and control of containment H 2 concentration. A) Containment pressure < 65 psia ( This verifies that containment' pressure is being maintained less-than its ' design pressure of 54 psig (68.7 psia). B) Containment temperature < 280'F: This verifies that containment temperature is-being maintained less than its design temper- [~h ature.of 300'F. A,)
~
WP84989 SECTION.VII - 7.0 PAGE 21
- .I ~ , , -. ._ . - . . _ . . , , . . . . _ . - ..._,...-._._,.-_.a_.....c . ,, ,.. _ , _ _._ _ _ _
~c C) Within 24 hours after the start of the LOCA, i l('N' commence containment 2H monitoring per OP' r, 2104.44:
i The post accident Hz analyzers should be placed in service as soon as time permits. After about i 24 hours, the worst case containment H con-centration may begin to approach a significant level (~ 2%-2.5%). The analyzers need to be in-l
, service at this time to ensure that the H concentration is maintained within acceptable. l levels. ,(g' D) Within 72 hours after the start of the LOCA or M.
if containment H concentration reaches 2% Hz , commence hydrogen recombiner operation per OP-2104.44:
'The worst case Hg concentration is not_ expected i
to exceed 3% H 'within 72 hours after.the LOCA. F If H recombiner z operation is commenced within 9
'72 hours, the H concentration :should not exceed -
p-.
~3%. This is assuming' operation of only'one H a recombiner. The H2recombiners should be placed in operation at 2% Hz to prevent further increase of the H concentration. This vill ensure that } .a combustible concentration of 4% H 2 is avoided. ~WP84989 SECTION VII - 7.0- PAGE 22'
;7q STEP 5: Verify RCS heat removal:
L'u ) l NOTE l l S/G levels may indicate up to - 5% higher than actual due to elevated l l containment temperatures. This is due to the decrease in density of the l l water,in the. reference legs'of the S/G level transmitters. The actual l l level error can be obtained from Figure 4. l A) S/G level (s): During a LOCA, S/G levels need to be maint'ained to allow RCS heat removal via the S/Gs. On a small break LOCA, the S/Gs are a major means of decay heat removal. On a large break LOCA, the (~3: S/Gs may not be required for decay heat removal A_/- but are utilized for additional RCS cooling.
- 1) Verify that EFW is maintaining S/G. levels at the EFAS setpoint: 1 This will ensure that sufficient S/G level is maint'ained to' allow the S/Gs to function as a heat sink for the RCS.
[} y
- WP84989 SECTION VII'.- 7.0 PAGE 23
, . , 2) Secure the running HFW pump:
Once EFW has been verified to be in operation and S/G levels are being main-i tained, the MFW pump is no longer needed. l l l
- 3) If possible, align EFW pump suction to the l l
S/U B/D DI effluent by opening 2EFW-0706: At least one condensate pump must be running with short path recire flow established through a S/U B/D DI before the EFW suction can be aligned to the S/U B/D DI effluent. fw This is done to conserve CST. inventory. - b +
- 4) If all feedwater flow is lost and' the S/Gs boil dry,' indicated by RCS temperature greater than S/G temperature (T
~ ~
sat corresponding to S/G pressure) and increasing, perform the following: a) - Open the ECCS vent isolation valves,
' 2CV-4740-2 and 2CV-4698-1.
b)' Verify maximum possible unthrottled safety injection flow. n WP84989 'SECTION VII - 7.0 PACE 24
, _ , .,.---.-,_.-,--% , -- ,, ..c-, . ,...,- ,,. . _ _ , . . - -,,, ~m. , ,,.y_ ._r- ,,.r._.-- - ,
~ t c) Verify all available charging pumps b,s ' running. This action is taken to establish RCS feed and bleed cooling in the event that the-S/Gs are lost as a means of RCS heat-removal. On small break LOCAs where the flow through the core and out the break is not sufficient to remove all of the core decay heat, the S/Gs are required for l additional heat removal. If all feedwater sources are lost and one cannot be regained-by the time the S/Gs boil dry, feed and ["') ~ bleed cooling must be established to' w provide core heat removal. The sources of feedwater include EFW, MFW (using MFW pumps and condensate pumps) or condensate pumps alone. Since the operator may not be able i to tell if'the break flow is sufficient for core heat removal without the S/Gs, any-time the S/Gs are lost, feed and bleed cooling is established. When the S/Gs boil dry or_not enough inventory is
~ ^
available to remove.the heat being produced, RCS temperature will begin increasing. When RCS temperature can no-
, a WP84989 ,
SECTION VII;- 7.0- PAGE 25 E--.
1 I l I longer be maintained by removing heat from ..(_)# . the S/Gs, the S/Gs are considered to be lost as a RCS heat sink. This should be indicated by RCS temperature increasing above S/G T and continuing to increase. Opening the pressurizer ECCS vent isolation valves should provide a steam / water flow path of sufficient size to reduce RCS pressure enough to allow sufficient HPSI/LPSI/ SIT injection to ensure core cooling. The safety injection system provides the feed for feed and bleed cooling of the RCS, If feed and bleed cooling is initiated, two HPSI pumps and both'LPSI pumps should be verified running and all HPSI and LPSI cold leg injection MOVs should be verified fully open. -LPSI will
.not be available if RAS has occurred.
Also, the charging pumps should be verified running to provide additional high pressure injection.
- [
~WP84989 SECTION VII - 7.0 PAGE 26
B) Commence a cooldown to < 300 F as follows:
- %j A rapid plant cooldown via the S/Gs, is beneficial for all LOCAs, particularly small breaks. For small breaks, the S/Gs are the major heat sink for RCS heat removal. An aggressive cooldown (while holding the cooldown rate within Technical Specification limits) improves RCS heat removal by enhancing natural circulation and reflux boiling. Furthermore, an aggressive cooldown hastens the depressurization of the RCS. This results in higher safety injection flows which aid in regaining RCS
, .g e- inventory control.
} .
For the largest breaks, the RCS depressurizes to an equilibrium pressure with containment.. In
~
this condition, the RCS fluid is at a lower, temperature than that of the S/Gs. The S/Gs, therefore, act as a heat source, superheating
- any steam in the RCS which may be flowing through the S/Gs to the break. By cooling down.
the S/Gs, heat input to the RCS is reduced. as
, NJ WP84989 SECTION VII - 7.0 PAGE 27 , + , ,- ,, .v-r ,, , . + - - - n..- , , , , , . . - - , , . , , - s,--, -., -, ,,
1 lc The RCS is cooled to < 300'F to allow SDC operation, if possible.
- 1) Take manual control of the.SDBCS and -
establish a cooldown rate of < 100 F/ hour It is preferred that the operator use the SDBCS bypass valve (s) in order to conserve secondary inventory.
- 2) Reset the MSIS setpoint, as required:
This will prevent a MSIS actuation as the RCS is cooled down and S/G pressure is reduced. A MSIS actuation would further complicate plant control during the LOCA.
- 3) ' If pos'sible, maintain RCS pressure and temperature within the limits of Figure 1:
If the RCS pressure has decreased to. saturation pressure, this may not b'e pos-sible until'further reduction of RCS-tem-perature is accomplished. The upper limit of'200*F margin to saturation should always be avoided until-within the SDC window. WP84989 SECTION VII - 7.0 PAGE 28 L g . .. . . . . . .. _ _ - - _ _ _ - _ - - - - _ _ - - - - - - - - - - - - - - - - - - - - - - - - ~ ~ ~ ~ " - - ^ ^ ^ ^
,e STEP 6: RCS inventory controls
( /L
. CAUTION STATEMENT *
- DO NOT OVERRIDE HPSI UNLESS THE RCS MARGIN TO SATURATION IS 2 30*F. .
. IF THE RCS MARGIN TO SATURATION DECREASES To < 30'F, RE-ESTABLISH . . MAXIMUM HPSI FLOW UNTIL 2 30"F MARGIN TO SATURATION EXISTS. . . THIS CAUTION'IS INTENDED TO PREVENT HPSI THROTTLING TO MAINTAIN . . PRESSURIZER LEVEL IF THE RCS IS NOT SUBC00 LED. .
j-(,s l NOTE l
~l. Pressurizer level may indicate up to - 3% higher than actual due to elevatedl l containment temperatures. This is due to the decrease in d$nsity of the l l water in the reference legs of the pressurizer level transmitters. The' l l actual level error can be obtained from Figure 5. l A) If pressurizer level is restored, maintain corrected pressurizer level 2 29% but s 82% as.
followsr. Maintaining pressurizer level 2 29% should' allow
.use of the pressurizer heaters while avoiding damage due to heaters not being covered. The .(~
- \~ ,s . WP84989 SECTION VII - 7.0- PAGE 29 h
_. . - upper limit of s 82% is given as an- upper (~) control limit and was chosen for consistency. N
- 1) Correct pressurizer level indications, 2LI-4627-1 and 2LI-4627-2B, for the reduced pressurizer temperature per Figure 3:
This is required because the post-LOCA pressurizer level instruments are calibrated for a water phase temperature of
~ 653 F.
If the pressurizer temperature is < 653'F, 1(~); the-density of the water in the pressurizer -i .'u will be greater- than the density' of. water . at 653*F. This will result'in an indicated level greater than actual level.
- 2) Override'and throttle'the HPSI cold leg injection MOVs.as required:
' d. ~ .During a small b'reak LOCA '(RCS does not ~-
completely depressurize) HPSI flow will
.4 ' continue to increase as_RCS pressure de- I ;
J
~
HPSI flow becomes greater than' the flow out
>WP84989: .SECTION VII - 7.0- PAGE 30 .\.-
, /
s 4 t -- of the leak, pressurizer level should be O
\ \ restored. If pressurizer level is , restored, HPSI should be throttled to g , i prevent the pressurizer from going solid, providing RCS margin to saturation is 2 30 F. The RCS margin to saturation must be 2 30*F because during certain situations, such as a pressurizer steam space rupture, ICC, or RCS voiding, pres-surizer level may not be an accurate indication of RCS inventory.
i , a) Maintain the flows through both HPSI ,
, i headers approximately the same:
[") - . s Keeping HPSI flows balanced will help
., J
( ,
^
maintain HPSI minimum flow requirements during RAS. , i s i b) Attempt to maintain approximately l ' equal flows to the four RCS cold ' i s legs: ( 1
. n 4 , This action should ensure appdbximately three fourths <of the total HPSI flow is t
delivered to the core.
) *I N - WP84989 SECTION VII'- 7.0 PAGE 31
- i. .
l B) If the LOCA is not due to the ECCS vent isolation O valves being opened, one hour after the start of the LOCA, perform the following: ,
- 1) Secure the charging pumps.
- 2) Secure the BAM pumps.
,~l' 3) Verify shutdown margin.
This action is taken in order to avoid the possibility of boric acid precipitation in the core which may occur on large breaks. For large breaks, the reactor vessel refills only to the elevation of the break. Borated water is injected into the reactor vessel via the charging and safety injection pumps and pure steam is boiled away. This may result in boric ( acid being concentrated in the reactor vessel.
, (
Securing the charging pumps helps limit the
- excessive buildup of boric acid in the reactor vessel. The boric acid pumps are secured because with the charging pumps secured, they no longer need to be running. Additionally, this will help prevent possible damage due to low
.t flow. The charging pumps are not secured when the ECCS vents are being used to ensure maximum 1
flow is delivered to the RCS for feed and bleed Q cooling. Boron precipitation is not expected to WP84989 SECTION VII - 7.0 PAGE 32
, 1 i: . ' - 'be a problem in this situation. On large' break n . -LOCAs, where the RCS remains saturated and boron
- . .-; precipitation is a' concern, S/D margin is
~
provided by the boric acid injected from the RWTD L , by the safety injection system. The beric' acid
~
injected by the charging pumps adds to this but
, _ :L .
is generally not required. On very small break LOCAs, where very little HPSI injection occurs,
, . . the boric acid injected by the charging pumps is l < required to maintain the available shutdown ~ '
margin as the RCS is cooled down. The boric' acid injected by two charging pumps running for 'qj 4 60 minutes'should always be enough to ensure adequate available shutdown margin is maintained. 1).
- Sufficient boric acid addition to maintain an:available shutdown margin of 5.5% may.be-
_g verified as follows: ,
+
r-9 ~ a) 1Obtain the required Mode _5 boron
-s a.
concentration for the present EFPD-4
,7 .-* from'OP 2103.15, Figure C-11:
Borong g = ppm ($f ' 4 .; ; ,. p . . .
. . ~
u]. . s _W P84989, M SECTION VII'- 7;0 PAGE 33
/
9 8 _ j, ."hy
, *Mi g: ~ ,_j- L c- ~: , . . ,,. .- .-.-, ,, , - . .:.,,,..,,,,,,,--,.. ~
t This is a conservative boron
~
concentration as it does not take credit for xenon, PLCEA worth or additional samarium. b) Calculate how long the available charging pumps must run to achieve this boron concentration: Run Time (Minutes) = (Boron FM - BoronhiM) (.18 min) ppm , Number of Chg. Pumps Running This equation is a simplified form of: Run Time (Minutes) = -(Boron g .- Eoron Initial ( 98 ppm gal,, n (Number of Chg. Pumps Running) (44- min)
~~L]
The constant of'8 gal / ppm was determined using the BORON 2 program in the CAPS computer. .A BAM tank concentration of 12,000 ppm is assumed and an initial RCS boron concentration of 1000 ppm is assumed. 'This will result in a very conservative shutdown margin sinct the rest of the cooldown' makeup required will come from the RWT via.the HPSIL~ t pumps and the BAM tanks are normally. maintained with a concentration of 14,000 ppm - 15,000 ppm.
~ ~
s{}; WP84989' SECTION'VII - 7.0. 'PAGE 34-c n-
.i
x c) If this time is less than 60 minutes,
- ( the available shutdown margin requirement is satisfied:
In this case the charging pumps can
?
be left off for the remainder of the cooldown. d) If this time is greater than 60 minutes, continue charging until the calculated time requirement is met: This could possibly occur if only one charging pump is available. In this case,_the operator may want to leave the charging pump running, or restart , it, until he is satisfied that the
, shutdown margin is satisfied.
r - 3 ( f_ -
' l ', ' ' ,~
, '. / ' y.. K,)
, .WP84989 SECTION VII 7.0 'PAGE-35
_,.. STEP ~7:l RCS pressure control: 3v )
.l NOTE l l.The use of pressurizer heaters and the throttling of HPSI injection MOVs l.
I should be balanced to maintain _a constant pressurizer level. This note is l l ' reminding the operator that pressurizer level will decrease when the l
- l- pressurizer heaters are operated and RCS pressure increases. Level l l decreases due'to the increased break flow. HPSI flow will have to be l ~
l increased to maintain pressurizer level. l A) If corrected pressurizer level is restored to 2.29%, restore operation of pressurizer heaters and e.ttempt toLaccomplish the following:
/~T _ ?. ,)
- 1) Maintain RCS margin to saturation 2.30'F but < 200'F per Figure 1:
' This step attempts to regain RCS pressure control in order to establish and maintain a . . proper RCS margin to saturation. If possible',
RCS pressure should be controlled along with the
.- RCS cooldown to maintain the. desired RCS conditions.
(
/ _
b._" ) : WP84989 SECTION VII - 7.0' :PAGE 36 k W'm M
os n- . B) If necessary, use auxiliary spray to control
-pressurizer pressure:
This step directs the operator to use auxiliary spray to reduce RCS pressure if no other means are available.
- 1) If the pressurizer and charging water temperature difference is 2 200*F, complete Attachment "A" of OP 2103.05 for each spraying cycle.
C) Secure all RCPs prior to RCS pressure decreasing r~% to 290 psia () : This step reminds the operator to observe the
<RC? operating requirements as RCS pressure.is reduced during the.cooldown. ' STEP 8: _ If RCS margin to saturation is 2 30*F and RCPs are -not restarted, verify natural circulation as follows: -( A) . Hot leg temperatures (Th) have stabilized'or are slowly decreasing. . B) Cold leg temperatures (Tc) have stabilized or are slowly decreasing. - (~N. -
A.,( ,
'WP84989 SECTION VII -17.0 PAGE 37 4 / J h
t er .
_C). RCS AT h(T - Tf) is less than 50 F.
.D) No abnormal difference between core exit.
thermocouples and hot leg RTDs. E).- Continuous demand for EFW flow to maintain constant steam generator level (s). F). Continuous demand for the operation of the SDBCS . valve (s)-or S/G safety valves to maintain a - constant S/G pressure.
< Adequate instrumentation is available to monitor ~
natural circulation for the single. phase liquid natural circulation process. The RCS temperature instrument'a' tion, namely loop ATl:can be used.alon'g- _ p: with the'other information to confirm that the single
. phase natural' circulation process'is effective. The -natural circulation processes. involving two phase-cooling are complex and varied enough so that RCS AT . may not be a meaningful indication of adequate natural circulation = cooling. >The~above indications - e of natural circulation! should ~only be used when RCS- '- N .'
inventory and pressure are controlled. For-cases where two phase natural circulation cooling is the heat removal process,'the. operator-relies upon.
; : maintaining the S/G heat removal process and the strict rules-that require safety injection to be t
operating:to restore inventory control. In addition,
~
l - \
. u. . -
7WP84989 'SECTION VII - 7.0 PAGE'38 2 y
.~. '
a the CET temperatures and.T indication are important I(;,)? H in monitoring heat removal during two phase natural circulation cooling. As long as these temperatures c remain within' acceptable limits, they indicate that heat removal and inventory functions are being satisfied. STEP 9: If actuated, secure the containment spray system as follows: Termination of containment spray may be useful in providing an easier recovery from the LOCA. The continuous use of containment spray may impact the 7-~y. operation'of equipment inside cont'ainment. Since the
\.]
containment pressure may increase again, the containment spray system should be maintained aligned for automatic operation. The' containment spray-system may be manually rest'arted-to control iodine'- 4 levels in containment. iA) The containment spray system may be secured if-the following_ criteria are satisfied: P 1
- s -.
Ib
;g_ a \_) a WP84989 SECTION VII - 7.0 -PAGE 39-4 f__ f
-q 1) Pressurizer level maintained 2 29%'but Uf ,
s-82%: This ensures RCS inventory control has been regained. If RCS inventory control has not been established, SDC operation may not be possible and the containment spray system may be required 'for long-term cooling.
- 2) RCS margin to saturation is 2 30*F:
This ensures.that RCS pressure control has JPs- been regained. With pressure control, the Rf RCS can be maintained subcooled which is the desired state for'RCS heat removal via the S/Gs.
-3) 'S/Gs are available to remove RCS heat: '
- N ~
The S/Gs must be available to remove the RCS heat prior.toLcontainment' spray termi-
~ ' nation. If the S/Gs are not available, the.
shutdown cooling heat exchangers are the
-only means of removing heat. In this case, s- ; containment spray should remain in operation f(T ~ %../
until SDC operation can be established.
.g7 ;WP84989 SECTION VII - 7.0 PAGE 40 i n-k %
. [, . 4) Containment pressure is being maintained I ~- ( < 23.3 psia:
1A This ensures that containment pressure has been reduced to an acceptable level. This also allows the CSAS to be reset and the equipment secured normally instead of being
.overriden or placed in pull-to-lock. With the CSAS reset, the system can be maintained aligned for automatic operation.
5)~ The containment cooling system is in
-operation:
d,J /'\ '
.The containment cooling system must be in 'O operation for containment spray termination to provide a means of condensing the steam in containment to reduce and maintain;contain-ment pressure.and temperature. This should 4 include at least 2 containment cooling fans, i
cne off of each loop of SW.
^
- B) ' Reset CSAS:
- _CSAS is reset to allow the equipment to be secured normally.
lI~'l
;\ /
WP84989 SECTION VII - 7.0 PAGE 41-i l.T. :-.-
t L C) Stop the NaOH pumps.
-j ,y b '*'#
D) Close the NaOH tank outlet valves. E) Stop the containment spray pumps. F) Close the containment spray header isolation valves. Monitor containment pressure: G) Verify CSAS actuation if containment pressure increases to 2 23.3 psia. STEP 10: Vent the SITS as follows: A) If RCS- pressure has stabilized above SIT f- . pressure, prior to decreasing RCS pressure below
..\ f .
650 psia during a deliberate cooldown and depressurization, vent the SITS when RCS pressure is < 700 psia but > 650 psia: w During a controlled and deliberate cooldown'and depressurization',' the SITS should be vented to avoid injecting the-contents of the SITS into , the RCS. Venting also avoids N, injection into the RCS when pressure decreases to approximately
-200 psia. Not venting the SITS would mak'e RCS pressure reduction during the cooldown very difficult and could result in an undesirable /~T .1:(-/ ' . . -
WP84989 .,,
~ , SECTION.VII - 7.0 ", PAGE.42 m ,.,.,c - ~ . ,
increase in pressurizer level. Venting is used 7_
^J'- -
because the SIT outlet valves cannot be closed with a SIAS present. B). If RCS pressure has decreased to the point of SIT injection, consideration should be given to venting the SITS prior to pressure decreasing to
~ 200 psia:
By the time SIT pressures have decreased to '
~ 200 psia,-their entire volume of borated water will have been injected into the RCS. Further injection will only result in N2 introduction
(' into the RCS. The SITS should be vented at. this t
' U}. -
- . pressure to prevent Na from' discharging into the RCS wnen-the RCS pressure is reduced.
' STEP 11: ' Place the pressurizer LTOP relief valves in service when RCS temperature is between 275'F and 270 F.as.
follows: t
.The LTOP relief valves -are placed in service to protect the primary pressure boundary from low:
temperature brittle fracture. Placing the LTOP relief valves in service between 275"F and 270'F will prevent exceeding the system hydro curve and the Jq f WP84989~ SECTION VII - 7.0 PAGE 43 i s
non-critical heatup and cooldown curves on Technical
.'9\ . Specification Figure 3.4-2 in the event of an inadvertent safety injection actuation.
A) Verify RCS pressure s 400 psia: This will ensure that the RCS pressu e is below the LTOP relief valve setpoint of.430 psig. B) Open 2CV-4730-1, 2CV-4731-2, 2CV-4740-2 and 2CV-4741-1: This unisolates both LTOP relief valves.
~'O STEP 12: If RWT. level decreases to S 6%, verify RAS actuation Per Appendix F and perform the following:
A) Isolate the ESF pump rooms:'
- 1) Close and dog ESF pump room doors.
- 2) Close 2 ABS-5 AND 2 ABS-6, ESF pump room.
floor drain isolation valves. The ESF pump _ rooms are isolated to ensure no gaseous or particulate radioactive, material is released to atmosphere from the recirculated f) u WP84989 SECTION VII - 7.0 PAGE 44 i' I
I
,,a RCS. This could occur if there were any leaks t
such as packing, flange or seal leaks. This could be released to the auxiliary building atmosphere which has a non-safety ventilation system that is not required to be operating. B) Verify required HPSI and containment spray flows are maintained:
- 1) If HPSI header flows are decreased to
< 200 gpm, shift all.of the flou to one of the HPSI pumps and secure the other HPSI pump. Monitor pressurizer level during this evolution.
('w)p
- 2) If.all HPSI injection MOVs on HPSI header are ever fully closed, secure all HPSI pump (s):on that-header.
Upon receipt of RAS, all mini-recire valves go' shut. The only long-term minimum recire protection for.the HPSI pumps is opera, tor action. If the operator throttles HPSI flows to-
< 200 gpm (about the minimum that can be ~
accurately-read on the HPSI header flow meters)
' a HPSI pump should be ' secured. All-of the flow should be shifted to the pump to be lef t running .; 3 -i )*
WP84989 SECTION VII - 7.0 PAGE 45
!1
I I to maintain the correct inventory control when i'
.E the other HPSI pump is secured. Since HPSI is being throttled to maintain pressurizer level,.
this level should be monitored during this
- evolution. Both HPSI and containment spray ,.
flows should be verified to be unaffected by the suction shifting on RAS. Problems could arise from foreign material entering the suctions of the pumps from the containment sump. STEP 13: - If the RCS margin to saturation has remained < 30*F for'> 2 hours and the LOCA is not due to the ECCS vent isolation valves being opened, align HPSI for.Th
.f-~g injection as follows:
hs J : Simultaneous injection into the hot and cold legs is used as the mechanism to prevent the precipitation of boric acid in the reactor vessel following a break that is too large to allow the RCS to refill. t. Injecting to both sides of the reactor vessel ensures that fluid from the reactor vessel (where the boric acid is being concentrated) flows out the break
- regardless of the break location and is replenished with a dilute solution of borated water from.the other side of the reactor vessel. The action is
- n WP84989 SECTION VII - 7.0 PAGE 46
,4 .. , . . _ _ - . _ . . = _ . _ . . _ . , . _ - . _ _ . . . _ . _ . _ _ - _ . .. - _ . . - _.. _.
- ;- i . f -
w - . : b-E '
. taken-no sooner.than two hours after the LOCA since _ ,
- _Qr '
t, the fluid injected to the hot leg may be entrained in .' 1 the steam being released from the core and hence possibly-diverted from reaching the reactor vessel. , ' 'After two hours, the core decay heat has dropped 1 - sufficiently so that there.is-insufficient steam
.o ,' ,
velocity'to entrain the fluid being injected to the y hot leg. The action should be taken no later than four hours after the LOCA in order to ensure that the < buildup of boric acid is terminated well before the
- v -
- potential for boric acid precipitation occurs. Since i
this action is only required for large breaks (where core,boiloff provides cooling), HPSI does not have to. g b'e lined for TH injec i n the RCSMs s@ cooled.
' Simultaneous hot and cold leg injection-is not.
, . necessary for small breaks because :for_ them, the _ buildup of boric acid is terminated when the-RCS is .
* ~
refilled. Once the RCS is'~ refilled, the boric' acid is_ dispersed throughout the RCS.via natural:
, : circulation. If the LOCA is due to the ECCS vent 1
isolation valves being opened-due to the-S/Gs being lost as the RCS heat sink, T injec i n is n t H _ ' initiated. In this: case,'the RCS should not-remain
~ ' saturated. 'It is desired to maintain all'of the.HPSI n- = flow into the cold legs, through the: core and.out the-
_ ECCS. vents. s JO: - n x '
-WP84989i SECTION VII - 7.0
_PAGE_41
. . . . _ pgg
_< ._..,.,,,-,.v.w..e. m e g, r-
t ( ) 1 L A) . Close breakers.52L5 and 62G2: fiV This will make power available for the operation of the HPSI-T ne nM s. H B) Close 2CV-5103-1 and 2CV-5104-2,.HPSI orifice bypass MOVs: These valves are closed first to prevent excessive HPSI flow. Closing the orifice bypass MOVs will force all cold leg injection through 0-the HPSI header orifices and provide roughly.a 50-50 split between-hot and cold leg injection. 7 when the Tg injection MOVs are opened. The.T H
- injection MOVs.should be positioned as soon as
- the orifice ~ bypass MOVs begin. closing. 'This m' ,
will maintain proper HPSI flow for core cooling. m. f
~
C) Modulate 2CV-5101-1 and 2CV-5102-2 to establish -
' half of the HPSI flow as.T g. injection flow: ~ . .
i: , i. 1)- Cold'l'eg-injection flow, the sum of 2FI-5014-1, 2FI-5034-1,'2FI-5054-2'and
, '2FI-5074-2,:should be half of' total HPSI:
iflow, the sum of 2FI-5101-1: and 2FI-5102-2: 9 % . f. J . WP84989 SECTION VII - 7.0 PAGE 48-ya
' A H .~ ~
s t j_ Since no indication of T H nje nf w s
~#
provided, this is the only way to determine when a 50-50 split has been established. STEP 15: Determine if the following criteria for shutdown cooling system operation are satisfied: Shutdown cooling operation is desired, when possible, to provide for easier recovery from the LOCA. Its operation should allow RCS depressurization which
-will minimize the leakage from the RCS. Shutdown cooling, along with HPSI injection for inventory control, should provide a stable, long-term means of core decay heat removal. -r T U-A) Pressurizer level > 29% but s 82%:
This ensures RCS inventory control has been established. Inventory control is necessary to ensure a suction to the LPSI pump from the RCS hot leg. B) .RCS temperature <-300'F: This ensures that RCS temperature is within the limits of Technical Specification 3.4.9.1. n)l ( LWP84989 SECTION VII - 7.0 PAGE 49 ~
,~ -C) RCS pressure < 300 psia: -k)s .-
This ensures that RCS temperature is within the limits of Technical Specification 3.4.9.1.
- 1) If RCS voiding is preventing RCS pressure reduction, attempt void elimination as follows:
a) Repressurize and depressurize the RCS within the limits of Figure 1 by operating pressurizer heaters, auxiliary spray and HPSI: Repressurizing and depressurizing_the RCS may condense the void. Repres-surizing has the effect of filling the voided portion of the RCS with cooler fluid which will' remove heat from this ! region. Depressurizing and repeating this process several times will cool and condense the steam void. WP84989 SECTION VII - 7.0 PAGE 50 e
l b) If necessary, operate the reactor
~ -vessel head vents:
The reactor vessel head vents will clear non-condensible gas veids in the head within minutes. Centinued head venting will result in steam venting, if a void is present, which will provide cooling for collapsing the void. c) Verify S/G pressures are 5 RCS pressure s f s
- 1. This will ensure no voids ~are present
-. y .
in the S/G tube bundles. S/G pressure is reduced less than RCS pressure by cooling from steaming or' feedwater addition. Cooling the S/Gs will not have an effect.on non-condensibles in' the tube bundles..
-D) RCS margin to saturation 2'30'F:
This ensures RCS pressure control-has been established and that the RCS is being maintained
~
in'a subcooled state. -This is necessary.to A. G-WP84989 SECTION VII - 7.0
'PAGE S1' , + i'
". r . - . . - - -
,_ provide proper NPSH to the LPSI pumps and to ?' ?-
allow the S/Gs to be used to reduce RCS c'm-s perature to < 300*F. E) Verify radiation levels will permit access to the shutdown cooling system: This is only expected to be a concern if RAS has occurred and RCS activity is abnormally high. No fuel damage is expected for LOCAs that will-
, result in the RCS conditions that allow SDC operation (small break LOCAs where RCS inventory control is established).
fy.
'(_)
STEP 16: -If the shutdown cooling criteria are satisfied, perform the following, if desired: A) If RAS has actuated or is expected to actuate, have the Electrical Department lift leads to remove the RAS trip from the LPSI pump to be useds.
/
This is required to allow a LPSI pump to remain running or to be started. Since there are l several possible leads that can be lif ted to remove the RAS trip, it -is left up to the . r im 4-
'LJ-LWP84989- SECTION VII - 7.0 PAGE 52 ~
a
.,s / T ' electrician as to which lead he desires to ~' .)
lift. This action is not expected to take very long to accomplish. Even if RAS has not actuated, the lead should be lifted to prevent later loss of the LPSI pump. B) Verify that the containment spray-system is . secured per Step 9 of this tab: 1 Containment spray may not even actuate on a LOCA of the size that will allow normal SDC operation. If it did, it must be secured to allow the.LPSI and containment spray systems to 4/~N be aligned for SDC.
'k ]
C) If containment pressure is < 18.4 psia, bypass ' the low pressurizer pressure trips via the key swithces cut the PPS inserts on 2CO3 and reset s SIAS: This will allow normal securing of the safety injection equipment. If containment pressure is not below the SIAS setpoint, SIAS will not be able to be reset and equipment will'have to be overridden or placed in " pull-to-lock" to be secured. WP84989 .SECTION VII - 7.0 PAGE 53 I
v D) ' Verify'RCS pressure > 200 psia and secure the J (N ')E
.LPSI pumps:
This verifies that RCS pressure is above the shutoff head of the LPSI pumps and.LPSI injection is not occurring. If LPSI injection is in progress, HPSI' injection is not sufficient to maintain RCS inventory and the LPSI pumps should not be secured. E) Close the LPSI injection MOVs: This will allow a controlled LPST system. warmup per the SDC procedure. F). Place the SDC system in service per'OP 2104.04, Section 6.0: This procedure will supply'the steps and valve _ alignment necessary to place the SDC system in operation. STEP 17:: If the shutdown cooling criteria are not satisfied,. l perform the following:
- A) Maintain HPSI injection for RCS inventory control and heat removal.
, WP84989' SECTION VII - 7.0 PAGE 54' L_:
B) Maintain containment spray and the S/Gs for RCS-
-(') . ~. and containment heat removal.
During a large break LOCA, RCS inventory and pressure control may not be re-established. In this case, an adequate suction for the LPSI pumps from the RCS hot leg cannot be assured. This will prevent normal SDC operativns. With LPSI flow, full HPSI flow and containment spray flow, RAS will actuate fairly early-into the LOCA. This will terminate LPSI and provide SW cooling to the SDC heat exchangers. HPSI T *"d c 3 TH injection will be maintained to keep the core covered and provide water for core boiloff cooling. !- : The containment spray system, which actuates on a
- large break LOCA, is left running to provide cooling for the water that is being recirculated through the core by the HPSI system. The S/Gs are maintained to.
provide additional RCS cooling. C). Proceed as directed by plant management: If normal SDC operation is not possible, plant =
' management will need to evaluate the situation and decide on the best means of recovering from the LOCA.
O m) WP84989 SECTION VII - 7.0 PAGE 55
r
- 1) Consideration should be given to the-
.k) alignment of a LPSI or containment spray pump to take a suction from the containment sump.and discharge to the RCS via the LPSI injection MOVs. The shutdown cooling heat exchangers should be utilized for heat removal. The following limits should be observed:
a) Limit LPSI pump flow to < 3500 gpm. i b) Limit containment spray pump flow to
< 3200 gpm. -l(' 'M The objective of lining a LPSI or containment-spray-pump to the containment sump and discharging through a SDC heat exchanger into the RCS is to allow containment spray to be secured. This will minimize further damage from containment spray and allow people to eventually enter the' containment building. The LPSI pump flow limit of < 3500 gpm ensures adequate available NPSH
- p'
.X_/,
SECTION VII - 7.0 WP84989 PAGE 56
c -;
- s. ,
a P p1 - . when the I. PSI pump suction is. aligned to . the containment sump. (Reference 1)- The
-containment spray pump flow limit of <.3200 gpm ensures that the pump motor rating is not exceeded. (Reference 13)
I ~ m s
)
E: . 1
+
J I' V
^
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s E' J 4 WP84989' SECTION VII - 7.0 PAGE 57
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8.0= STEAM GENERATOR TUBE. RUPTURE WITHIN CHARGING PUMP CAPACITY / \ ) RECOVERY ACTIONS
~8.1 Operational Goals The primary operational goal of the Ste.m Generator Tube Rupture (SGTR) within Charging Pump Capacity Recovery Tab is to prevent the. release of radioactivity to the public and to minimize the spread of contaminated liquid while placing the plant in a stable condition. This goal is generally achieved by the performance of the following:
- 1) Performance of a controlled shutdown
- 2) -Verification of safety function controls
- 3) Identification of the affected steam generator (S/G)
- 4) cooldown and depressurization of the RCS to below the lift pressure of the S/G safeties
- 5) -Isolation of the affected S/G
- 6) Continued cooldown of the RCS to reach shutdown cooling (SDC) conditions s
5 T f') N) WP84989 .SECTION VII - 8.0 PAGE 1
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8.2 Description of a SGTR within Charging Pump Capacity A. A SGTR is a penetration of the RCS pressure boundary within a
- S/G resulting in the radioactive contamination of,the secondary
- systems. _ The penetration can range from the failure of'an etch pit, a.small crack in a U-tube or tube sheet veld, to a
- double-ended shear of one or more tubes. -The loss of integrity in_the S/G tubes can be initiated by.several factors: corrosion
,. in the's/G due to poor. chemistry control, mechanical wear on components due to foreign materials in the S/G, manufacturing defects or excessive thermal or hydraulic stresses . imposed by plant transients. Anytime a plant transient occurs, the operator should be aware , g of the potential for this accident. This tab provides operator V guidance for loss of RCS inventory within the normal capacity of the CVCS system. This leak differs from the classic loss-of. coolant accident' in that the back pressure ' from the S/G secondary
~
, ' side opposes flow, somewhat minimizing the' flow rate. x Also in a-SGTR there is a greater potential'for a release to the environment. In a LOCA the leak will probably be inside containment or: isolated upon' initiation of SIAS signal, whereas in'a SGTR'the-reactor coolant (which has leaked into the S/G) can exit containment through the steam lines. Of very high priority is limiting releases;.therefore, a controlled shutdown to.within the capacity {^ ~o f the SDBCS bypass valves (~ 28% power) prior to a trip is highly
! desirable. LLifting of the steam line safeties or use of the SDBCS f>1 - 'WP84989 SECTION VII - 8.0 PAGE 2 + I' + --,ne- e n ,.r . 4 .,se,.r,.v.- .-e. em .,,,,,--n-m<v, .,-m-,--m.,w...n,w.,,,,,mm, ,, ,<,w.m,agn,wm-,,----. -r,,np , , -
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, _ atmospheric dump valves provides a direct release to the A /. surroundings. Raising S/G pressure to the lift setpoint of the steam line safeties could be accomplished in two ways: by RCS heat transferred to the S/G or RCS leakage into the S/G.
Reducing RCS temperature below 500 F reduces the possibility of lifting a safety since the saturation pressure of the primary coolant is below the lift pressure of the steam line reliefs. Therefore, reducing RCS temperature as soon as possible is a primary concern. Reducing RCS pressure to less than 1000 PSIA prevents pressurizing the S/G from the RCS to a value above the steam safety setpoint. This second process has a built-in time delay: The pressure drop across the leak keeps the S/G from seeing high RCS pressure until the S/G fills sufficiently to drive S/G pressure up. The optimum operator response to control RCS inventory and contain radionuclide release is to equalize RCS and S/G pressure as soon as possible, while reducing RCS pressure below the lowest steam line safety relief setpoint
-(1078 psig), and to control RCS temperature to preclude lifting of S/G safeties by heat transfer to the S/G.
U WP84989 SECTION VII - 8.0 PAGE 3
Early in the event the operator should identify which S/G has
\/
the leak or which has the greater leak as determined by higher radiation readings, so that S/G can be isolated to minimize contamination of secondary components. The leak from a failed tube cannot be isolated, so the leak will continue until the plant is cooled down, depressurized, and drained below the S/G tube sheet. Entry into Mode 3 conditions does not alleviate the symptoms of the accident. Delays in the cooldown can occur due to failures in other plant systems which may make the SDBCS bypass valves unavailable. If possible, these failures should be corrected prior to cooldown to minimize releases; however, to 4 expedite cooldown they may have to be corrected while cooling down.
. (\
U/ . The leak rate through the tube will increase with an increase in primary pressure, _therefore minimum pressure should be maintained above a 30 F margin to saturation. In this situation the RCS is highly susceptible to voiding, _ especially in a natural circulation cooldown. Actions should be taken to minimize voiding; however, a small amount of voiding which does not restrict flow is acceptable. Cooldown and depressurization should be performed rapidly to minimize releases. In this event the affected S/G is used as a storage tank to contain the leakage and to some extent becomes an extension of
'the reactor coolant system. It acts as a heat source during /'N . ' U WP84989 SECTION VII - 8.0 PAGE 4
cooldown as it contains a large water volume and is not steemed 7y s or is steamed minimally. This provides an increased heat load on the unaffected S/G, reducing cooldown rates. Forced flow should be maintained through the affected S/G to ensure heat is removed from it to prevent void formation in its tubes. Isolation
-of it is necessary to prevent releases to the environment and -
reduce secondary plant contamination; however, it may have to be steamed occasionally to prevent overfilling. The operator should try to limit the degree of secondary plant contamination without inhibiting mitigation of the event. Overfilling of the affected S/G should be avoided. If the S/G safety valves lift in a water environment, they could be damaged to the extent that they might not reseat. 8.3 Safety Functions Affected A. RCS Inventory Control Reactor coolant leakage to the secondary side of the S/G-affects the RCS inventory control safety. function. The event covered by this tab should not significantly affect pressurizer level since the leakage is within the normal makeup capacity of the CVCS. Miner-fluctuations may occur as the charging and letdown flow adjust to maintain level. Volume control tank level must be monitored to maintain level, as it.may decrease rapidly, pi b ' WP84989' SECTION VII - 8.0 PAGE 5
B. RCS Pressure Control _('-j,) The RCS pressure control safety function may be slightly affected,' depending on how rapidly the CVCS system reacts in maintaining pressurizer level. A small reduction in
- i. pressure, if any, may occur.
C. RCS Heat Removal When the affected steam generator is isolated, the RCS heat removal safety function is affected. The affected S/G will act as a heat source to the unaffected S/G. If the affected S/G is not cooled down-with the RCS, voiding can occur in its tubes as the RCS is depressurized. 8.4 Major Parameter Response A. Pressurizer Pressure and Level i e3 i The response of these parameters depends on the size of the
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rupture. A large lesh rate within charging pump capacity may result in a level decrease before the CVCS can react to maintain' pressurizer level. The level decrease will result in a corresponding pressure decrease until level is restored and/or pressurizer pressure controls respond. A mismatch will occur between CVCS charging flow and letdown flow based on the amount of leakage. B. Steam Generator Level and Pressure Steam generator level and pressure should not be significantly affected during power operation due to the relatively small amount of leakage in this event as compared to normal feed and steam flow. As the plant is placed in hot standby, the O
'. Q ,/
WP84989 SECTION VII - 8.0 PAGE 6
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~ leakage-into'the steam generator will become more evident 1,(.j'[
1:- / : and S/G level and pressure will then start to increase.
.s C. Radiation Detection Instrumentation Radiation ~ detection instrumentation will provide one of t . . the most evident indications of S/G tube leakage. The S/G.
sample cooler and main steam line rad monitors will show j elevated and alarming conditions on the affected steam a generator secondary side. A grab sample of S/G water from the sample-lines should provide backup indications to the F. '
-monitors. If the leak exists fpr some time prior to e detection, both sides may show elevated or alarming conditions 'due to mixing'of feedwater in the feed and condensate ~
system; however, the S/G with the leak should exhibit higher readings. If. both. 5/Gs -have leaks, both will show elevated readings, with highet levels of activity on the
-^
S/G with the larger. leak. (In this case the one with the larger leak is treated as the "affected S/G.") The condenser
~
off-gas monitor will also show elevated and possibly , alarming conditions as' gasses are removed from solution in the condenser. ? I d'
;U WP84989 SECTION VII - 8.0 PAGE 7 .,--, , ~# ,, , .. ~m.,,.... . _ . , .-c._..r, - ,2 . . _ _ .m-. . . , , - .. . . , _ - - . . , . ~ . , . - - , , . . - - . . . . , . . .
4 r 8.5 Basis for SGTR within Charging Pump Capacity Recovery Actions
._) *******************************************************************************
GO TO STATEMENT
- In performing this tab, if at anytime a reactor trip occurs due to the size *
* -of the SGTR being larger than makeup capacity, the Go To Statement directs
- you to the "SGTR Greater than Charging Pump Capacity." *
****************************************************************************n**
l NOTE l l When used in this tab "affected S/G" means the S/G with the rupture, OR if l l both S/Gs have tube ruptures, it means the S/G with the largest rupture. l
- 1. Verify charging and/or letdown systems are responding to maintain pressurizer level:
A) IF required, isolate letdown:
?O'-
B) Monitor VCT level and pressure: This step instructs the operator to verify charging and/or letdown are responding to conserve RCS inventory. Letdown should be no greater than 28 gpm if pressurizer level is low. Direction to isolate letdown is provided if pressurizer level is still decreasing thus reducing RCS inventory loss rate by at least 28 gpm. Reduction of reactor power within the capacity of the SDBCS bypass valves is desirable prior to tripping the reactor to reduce possible releases to the environment. (u-
'WP84989 SECTION VII - 8.0 PAGE 8 , _ _ . . . . . . . . _ ,+ . _.
() GO TO STATEMENT
- If'RCS inventory cannot be maintained, this Go To Statement directs tripping *
- the reactor and going to "SGTR Greater than Charging Pump Capacity" Tab. *
- 2. Verify the " permissive" handswitches for all SDBCS atmos-pheric dump valves are in the "0FF" position:
Atmospheric dump valves permissive switches are normally maintained in the "0FF" position. This step verifies the permissive handswitches in "off" to minimize potential release paths to the environment. S/G pressures will have to reach S/G safety setpoints (lowest 1078 psig) before jes3 steam release to the atmosphere occurs.
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- 3. Commence a load reduction at a controllable rate to within the capacity of the available SDBCS bypass valves AND perform the following:
The operator is directed to perform a load reduction at a
" controllable" rate. This tab covers SGTR of > .5 gpm in '
a S/G, to within the capacity of the charging pumps. The primary goal is not to release to the environment. If a reactor trip occurs prior to reaching available SDBCS bypass valves capacity (a maximum of 28% if all SDBCS bypass valves are available), the potential for O v WP84989 SECTION VII - 8.0 PAGE 9
l ? I atmospheric releases is larger. Therefore emphasis is . t [ 'l placed on performing a controlled shutdown. If a rapid L load reduction is performed, with a relatively large SGTR f' in progress, insufficient RCS makeup capacity may require a slower load reduction to maintain control of RCS inventory. Also of concern is that the release to the S/G and possibly secondary systems will continue until the RCS is drained below the tube rupture location. To minimize the release path a shutdown at the maximum " controllable" rate is desired. A) At - 60*5, remove one MFW pump from service. B) Remove heater drain pumps from service ~ 60% + 40'$. C) Remove third condensate pump from service at
~ 60% + 40%.
OP 2102.04, Section 9.4, gives directions for normal plant power decreases. This step supplies information where the required components are secured at the appropriate power ranges. The securing of a circulating water pump was specifically left out to minimize possible vacuum losses. Since a satisfactory vacuum is required for operation of SDBCS bypass valves the protection of this vacuum is desirable. If vacuum is lost, then a release to the environment cannot be prevented. r (! WP84989 SECTIO!! VII - 8.0 PAGO 10 L 9
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f G
- 4. Determine which S/G(s) has the tube leak by evaluating'the
(- k- ' L following parameters: A) S/G sample cooler radiation monitor (2RE-5854/2RE-5864) and/or trend recorder (2RR-2330) readings on Panel 2C25.
'B) Main steam line radiation monitor (2RE-1007/2RE-1057) readings on panel 2C336-2.
C) S/G water. sample radio-analysis: In this step the operator is directed to analyze available indications to determine which' steam generator has the leak. It is possible that a leak may exist in both steam generators, 'therefore the S/G with the greatest leakage as determined by higher radiation levels at selected points 7- will be considered the affected S/G. If the leak has been
'V present for an extended period of time, both S/Gs may indicate some amount of contamination due to mixing of feedwater, in which case the S/G with the higher _ radiation levels is considered for isolation.
- 5. Isolate any unnecessary flow paths on the affected S/G to minimize the spread of contamination:
The below listed steps serve to guide the operator in reducing the release of contamination to the turbine building and the environment. WP84989 SECTION VII 8.0 PAGE 11
. j~ 'L' -l NOTE l l IF both S/Gs have indications of tube leakage AND 2P-7B is available, l -l isolate both steam supplies to 2P-7A. This note ensures isolation of steam l s
l(to 2P-7A from both S/Gs, if both S/Gs have a leak, regardless of which is l [ considered the affected S/G. Prior to isolating both steam supplies to l l 2P-7A then verification of 2P-7B operable is required. l l l A) Close the following valves on the affected S/G.
- 1) 2P-7A steam supply "A" S/G OR
~~ "B" S/G 2CV-1000-1 2CV-1050-2 (Panel 2C17) (Panel 2C16) 7s This isolates steam from affected S/G to 2P-7A. ' N ,) '
The steam turbine for this EFW pump exhausts above the turbine building roof providing an uncontrolled release of contaminated steam to the environment. If a leak exists in both S/Gs and 2P-7B is not available, then the affected S/G is considered to be the S/G with the highest leak.
- 2) Steam Generator Blowdown "A" S/G "B" S/G 2CV-1016 2CV-1066 (Panel 2C17) (Panel 2C17)
WP84989 SECTION VII - 8.0 PAGE 12 l l b
,y Isolation of blowdown on the affected S/G reduces 9( /
the amount of contaminated water transferred to the' turbine building. Difficulties in restoring blowdown when isolating it from 2C02 has occurred. Since restoration of blowdown may be required for level control direction has been provided to isolate blowdown from the affected
-S/G at 2C17.
B) Initiate actions of OP 2203.15 to prevent the spread of contamination OP 2203.15 deals with reducing and controlling 7_s contaminated fluid in the turbine building support
).
systems. At this time, systems not required for power operation may be secured. Such systems include S/G sampling, steam traps,-etc. Sampling for radionuclides is initiated prior to pumping turbine building sumps and tanks.
- 6. When. reactor power has been reduced to within capacity of the available SDBCS bypass valves:
A) Transfer auxiliary electrical loads to startup #3 transformers l f)%.s' I IWP84989 SECTION VII - 8.0 PAGE 13 e
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7
,, A, B)! Start' main: turbine generator oil pumpsi.
AM- 1) Motor suction pump (2P-19) on Panel 2C01.
- 2) Turning gear oil pump;(2P-76) on Panel 2C01.
3). 'HP oil lift pumps (2P-90A-F) on Panel 2C12. e-. et C) . Manually trip the reactor Once reactor. power-is within the capacity of the turbine bypass valves'(maximum of 28% power), a manual.
'I transfer of electrical auxiliaries is initiated, . turbine oil systems started and the reactor is tripped.
- 7. . Verify all safety functions are satisfied:
. ,q 1 A), verify =the reactor is shutdown: -A /.
This step addresses the safety function of reactivity control by' ensuring that trip signals to selected
; sets of Reactor Trip Circuit Breakers (TCBs) have been received and verification that the reactor. is ~
shutdown. ;For all emergencies, ensuring the. reactor t is shutdown.and maintaining it' shutdown, thereby reducing the amount of heat generated in the core,. minimizes the consequences of the event. . P l WP84989 SECTION VII 8
. 0 PAGE 14
u a._ 1) Verify appropriate sets of TCBs are open s-v This addresses the proper operation of the breakers upon receipt of a RPS trip signal or manual trip signal and ensures that power to all CEAs is interrupted. An appropriate set of TCBs is defined as any combination that will de-energize both CEA power panels (2C70 and 2C71).
- 2) Verify all CEAs are fully inserted:
This step ensures adequate shutdown margin (SDM) (Technical Specification 3.1.1.1) to ensure that
-. - the ; reactivity : transients associated with ~'
postulated accident conditions are within acceptable limits. Calculations (per Procedure 2103.05, " Reactivity. Balance Calculations"),
. ensure adequate SDM with one CEA stuck at the withdrawn position. Therefore, if two or more CEAs are not inserted after a reactor trip, the reactivity control safety function is not to be considered satisfied, since a SDM of 5% cannot be immediately assured. \1 WP84989 _ .SECTION VII - 8.0 PAGE 15 N@
L. .. .__ . - - _ _ _ _ _ _ _ - . _ . - - - - ____-_-__w
il- )_ *
-V , GO TO STATEMENT *
- Direction to the Emergency Reactivity Control Tab addresses a failure of *
- the reactivity control safety function. -Entry into this tab will provide *
- guidance on options to de-energize TCBs (if necessary) and will direct the *
- operator to commence emercency boration to establish adequate shutdown *
- margin. *
- 3) Verify reactor power decreasing:
Verification of reactor power decreasing by available instrumentation ensures nuclear characteristics response is as expected. V B) Verify the turbine is tripped: This ensures that the major source of heat removal from the RCS.has been removed. The turbine trip also initiates electrical system transfers. Failure of the turbine to trip could challenge several safety functions,.such as: reactivity control, vital auxiliary power, RCS pressure control, and RCS inventory control. An uncontrolled RCS cooldown, due to the failure of the turbine to trip, could result in ESFAS actuations (i.e., SIAS, MSIS), and a O potential for. pressurized thermal shock (PTS) exists. Q) WP84989 SECTION VII - 8.0 PAGE 16
, 1) Verifying all turbine control valves OR all
'/ turbine stop valves are closed ensures that steam is secured to the HP turbine thus preventing overcooling of the RCS and possible overspeeding of the turbine.
- 2) Verifying all turbine intercept /stop valves are closed ensures proper turbine trip actuation and prevents a possible turbine overspeed condition.
- 3) Verify generator output breakers (5130 and 5134)
AND exciter field breaker are open on panel 2C01: This step ensures proper electrical isolation of the turbine generator and prevents motorizing 73, the main generator. C) Attempt to stabilize RCS pressure as lov as possible BUT above SIAS actuation setpoint (1766 psia): Reactor coolant pressure control is required to keep the reactor coolant subcooled so that the coolant is in the preferred state to transfer heat from the core to the S/Gs. This step addresses the RCS pressure control safety function and supplies information to ensure that it is maintained at desired setpoint. Proper automatic operation of pressurizer heaters and spray valve (s) is expected to maintain this safety r~x function under SGTR within charging pump capacity
)
WP84989 SECTION VII - 8.0 PAGE 17
j.e conditions, but. instructions for manual control of' d) V- pressurizer heaters, spray.. valve (s) and use of auxiliary spray valve is provided, if necessary. Operation of the pressurizer pressure controller (s) (2PIC-4626A or 2PIC-4626B) to adjust pressure to a
-desired setpoint may be required. Adjusting the controller to the desired setpoint allows the operator to maintain pressurizer pressure outside of the normal band if plant conditions require.
Pressurizer pressure is expected to be maintained above 1766 psia (SIAS setpoint) at all times, p- Maintaining pressure at a low value decreases the differential pressure between the RCS and the-secondary side of the S/G,' thus reducing the leak rate to as low a value as possible.
- 1) Take manual control of pressurizer heaters, AND/OR spray valves as necessary:
Taking manual control of pressurizer heater (s) and/or spray valve (s) would be the expected response for maintaining the RCS pressure control safety function should the automatic control systems fail. l3 x.J . WP84989 SECTION VII - 8.0 PAGE 18 _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ . . . _ _ . . _ _ _ _ . _ . _ _ . . _ _ _ . _ _ . _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ _ . _._m
- em,-. .2)' lIF pressurizer level decreases to < 29%, all 0N-pressurizer heaters in auto will be de-energized by interlock: Below this level, the pressurizer heaters will start to uncover and operation of the heaters is prevented. a) Restoring pressurizer level to > 29% prior-to re-energizing heaters ensures that-sufficient level to cover all heaters is maintained and prevents possible inadvertent loss of heater (s) operability. b) Restoring control to proportional heaters
-3 \
after interlock de-energization, requires placing spring loaded handswitch(es) to "0N", then release for return to auto. c) Restoring control to backup heaters'after interlock de-energization, requires placing handswitch(es) to "0FF", then back to "AUT0" or "0N".
- 3) IF pressure cannot be controlled with normal spray valves, manually operate pressurizer auxiliary spray valve to limit RCS pressure:
The use of the auxiliary spray valve may be-('] v required if the redundant normal spray valves
-WP84989 SECTION VII - 8.0 PAGE 19
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;;; . ,are inoperable OR if a loss of all RCPs is Y- experienced. ..Haintaining low RCS pressure, reduces the leak rate.
a) Verify at least one charging pump is running to supply auxiliary spray flow. b) Open 2CV-4824-2 (Auxiliary Spray Valve) on 2C09 to allow minimal; flow, thus preheating auxiliary spray line, c) Close 2CV-4827-1 AND 2CV-4831-2 (loop charging valves) on 2C09 to provide full flow through auxiliary spray line. d) Verify closed 2CV-4651 AND 2CV-4652 (normal pressurizer spray valves) on 2C04 to ensure full flow is directed through the auxiliary spray line When using the auxiliary spray valve,-finer pressure control may be.obtained by throttling 2CV-4651 or 2CV-4652 open and . allowing auxiliary spray flow to be
-diverted back through the main spray. line to the loop. This'also will minimize the number of spray nozzle' thermal cycles by eliminating the need to open and close the-auxiliary spray valve.
O WF84989 SECTION VII - 8.0 PAGE 20 a
m e) If the difference between pressurizer and q. A. charging water temperature is > 200*F, as measured by pressurizer water phase tempera-ture (2TI-4622) and regenerative heat exchanger to RCS (2TI-4825), then logging of each spray cycle is required to ensure Technical Specification (5.7.1) is met. GO TO STATEMENT *
- This statement directs the operator to the SGTR greater than charging pump *
- capacity tab, if RCS pressure control cannot be maintained. *
.- D) Verify Proper RCS Inventory Control:
- ^
(J RCS inventory control directly supports the RCS pressure control safety function, and together, they ensure that the RCS is maintained in a preferred state to transfer heat from the core to the unaffected S/G. Inventory control is intended to ensure an l . adequate amount of fluid is.available to provide a medium to remove decay heat. On a SGTR within charging pump capacity, the pressurizer-should retain some indicated level even though the heaters may be de-energized briefly on low level. Actions are selected to ensure proper automatic operation of the
,O \ l v
WP84989 SECTION VII - 8.0 PAGE 21 L.
I-- normal inventory control system. Also, proper inventory
-'. control provides a means to monitor for SGTR greater - than charging pump capacity.
- 1) Verify charging and/or letdown systems are responding to automatically restore and maintain pressurizer level at program level:
The automatic operation of the Pressurizer Level Control System (PLCS) is the preferred method for inventory control. The PLCS is verified to be functioning to restore pressurizer level to program level (~ 41%). If not, PLCS.should be
. f~.s operated manually to restore and maintain .I )
level above the heater cutoff (~ 29%).
- 2) Verify adequate suction source (s) to charging pumps:
The source (s) of water for use in controlling RCS inventory depends on the total amount of fluid necesrary for makeup to the RCS and the time frame over which the fluid must be introduced. Adequate suction to the charging pumps ensures adequate fluid is available to restore or maintain-RCS inventory.
?T.
L.) WP84989 SECTION VII - 8.0 PAGE.22 i t
,/ y a) -The volume control tank (VCT) is the primary \-)_ source of fluid for RCS makeup._ A VCT low level alarm (~ 57%) is expected and adequate VCT level is considered to be above the low o ' low level alarm (~~9%). Blending with a solution of greater than or equal to present RCS boron concentration ensures the Technical Specification SDM of 5% is met.
(OR) b) Verify RWT aligned to CVCS: If the VCT level decreases to 5% or if adequate makeup cannot be maintained to the VCT, the RWT should be lined up to the charging pump suction.
- 1) Verify open RWT to charging pump suction valve (2CV-4950-2) to ensure a continuous source of fluid is maintained at the charging pump suction.
2)_ Verify closed VCT outlet valve (2CV-4873-1) to prevent further decrease of VCT level. r j V '
'WP84989 SECTION VII - 8.0 PAGE 23
" b# - '* GO TO STATEMENT' *-
- This statement directs the operator to the SGTR greater than charging pump
- capacity tab, if pressurizer level' decreases below the indicating range.
E) Verify core heat removal:
'1) Verify RCS flow RCS forced flow is the preferred method of removing core decay heat. A pump in each loop is' desired, including the affected S/G loop. The affected S/G must be cooled down to prevent-voiding-in the S/G tubes. . f~') ~
a) Verify at leastrone RCP in each loop'is running: The operator verifies RCS forced flow by verifying RCP(s) are running. The primary indication of a RCP running is its' breaker being closed. This is indicated by the red closed light above the handswitch'being lit. -Normal RCP motor amperage indicated verifies that the RCP is actually connected to its power supply. Normal RCP AP indicated verifies that the RCP is actually (-- circulating fluid in the RCS. C)/ - MP84989 SECTION VII - 8.0 PAGE 24
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b) IF the RCPs are not running: , ()--
~
(1) Verify'RCP restart criteria are
+
satisfied, per Appendix H, . AND (2) Attempt to start one RCP in a loop with an operable spray valve first. THEN (3) Attempt to start one RCP in the opposite loop In these steps, the' operator is directed to reinstate forced flow with RCPs to enhance ' core cooling. Flow through the unaffected es _ S/G is required as a heat sink and flow l t'~ through the affected S/G is required- to precludevoidinginitstubesd$ringa cooldown. With no heat being removed by steam removal or feed, theLaffected S/G will-retain its heat,-and voiding could' occur in 3 its tubes as RCS pressure is reduced below the saturation pressure for its temperature.-
-The affected S/G will act as a heat source due to its volume of heated water, . adding a heat load to the. unaffected S/G being used for cooldown.
h
* ' " .WP84989. SECTION VII - 8.0 PAGE 25 ,? >
tg c) If RCPs cannot be. started, verify natural D ' circulation as follows: a Should RCPs not be available, natural circulation may be utilized for core cooling. Guidance is given in the following steps to verify natural circulation has been established.
- 1) Hot leg temperatures (T h) have
, stabilized or are slowly decreasing.
- 2) Cold leg temperatures (Tc) have stabilized or are slowly decreasing:
., t Hot leg temperatures (Th) and cold leg , temperatures (T,) should stabilize and may slowly decrease. This indicates that the AT has increased enough to establish the required flow to remove 3 the decay heat being produced. These indications of T hand T are c
assuming a relatively constant S/G pressure is
- - being maintained.
4 I h-I- r V WP84989 SECTION VII - 8.0 PAGE 26 l I
s
- ,gi 3) RCS AT (Th c-T ) is less than 50 F:
_t
% )..
RCS AT (Th -T ) should be less than 50*F. Actual testing and experience have shown that a AT > 50*F is abnormal and may indicate that natural circulation
' flow rate is degraded.
- 4) No abnormal difference between core exit thermocouples (CETs) and hot leg RTDs -
No abnormal difference between CETs and hot leg temperatures should exist.
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If CET temperatures increase much-above. T , natural circulation flow may be h
. insufficient.
- 5) Continuous demand for EFW flow to-maintain constant steam generator.
level. LO-
'WP84989 SECTION VII - 8.0 PAGE 27
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- 6) Continuous demand for the operation of R.
the SDBCS valve (s)'or S/G safety valves to maintain a constant S/G pressure: If the S/Gs are functioning as a heat sink for the RCS, there will be steam flow from at least one location. -I.f steam is released from the S/Gs, feedwater must be added to maintain . level. 4
- 2) -Verify RCS margin to saturation is 2 30'F:
The margin to saturation 2 30' ensures that the i t, reactor coolant:is maintained subecoled while allowing-for possible inaccuracies and uncertainties of the margin to saturation-calculators and their inputs. Circulating a.
- subcooled fluid is the preferred met' hod of e
removing core decay heat. 1 % b- _~ WP84989 SECTION VII - 8.0 PAGE 28 L_ _
5 $~ , .
, - a). IF RCS margin to saturation is < 30'F:
hhh Reverify RCS pressure control AND 1) ff[,7d inventory control safety functions, ll. , ~ '
'fg steps 7.C and 7.D of this tab This reverification is an attempt to discover the reason for low margin to saturation. .. 2) Monitor core exit thermocouple temperatures:
The operator should check CETs frequently to verify that heat'is being removed
. -i from the core and the core is maintained covered.
F) Verify RCS heat removal capability by verifying operation of SDBCS turbine bypass valves, MFW system
-and EFW system:
The removal of heat from the RCS is necessary to maintain long-term core heat removal. This step
' verifies operation of the systems required to maintain a S/G as a RCS heat sink since the S/G(s) are the primary means of removing heat from the RCS. )-
WP84989 SECTION VII - 8.0 PAGE 29 i L
,_ 1) Verify S/G pressure (s) AND Tave are being. main- '-)~
tained by SDBCS turbine bypass valves: By verifying S/G pressure (s) and Tave, the operator ensures that sufficient main steam is being removed from the S/G(s) to remove
. core decay heat from the RCS. Setpoint for , control should be as low as possible but above MSIS setpoint to minimize primary to secondary leakage.
If the main condenser is available, the SDBCS bypass valves .are the preferred method of main-taining S/G pressure. These valves are. pre-ferred because they do not result in a reduc-4
, tion of secondary inventory. In addition, there , is.less release to the environment. Also, one of_
the SDBCS bypass valves (2CV-0303) has a rating J of 5%. This valve provides more effective control'
, of S/G pres'sure. If. condenser vacuum degrades: , to the interlock setpoint, the SDBCS bypass valves will no. longer be available. , u 4
4 4 -.kE
=[~'}
- v. - .-.
LWP84989 , SECTION-VII - 8.0 :PAGE 30.
\' t ,
- 2) Verify S/G level (s) are being maintained:
79 V By verifying that the S/G levels are being restored, the operator ensures a source of feedwater is available to maintain the S/G(s) as the RCS heat sink. This step directs the operator to verify proper alignment of the main feedwater and condensate systems. The main feedwater and condensate systems should be automatically aligned to slowly restore and maintain unaffected S/G level at ~ 70%. _y A '- a) MFW system operating in " Reactor Trip Override".(RTO):- t' i The MFW system is verified to be operating
- in RTO. The " Control Element Drive Mecha-nism Control System" (CEDMCS) undervoltage L relays signal the "Feedwater Control Systems" (FWCS) to operate in RTO. Basically, RTO will position the MFW valves and adjust main
, feed pump speed to establish ~ 5% feed flow to the S/Gs. This will continue until the level setpoint is achieved.
. im WP84989~ SECTION VII - 8.0 PAGE 31 s
u.a. -
,. One main feed pump is verified to be opera- 'N ting at minimum automatic speed and the second main feed pump is verified tripped.
The main feed pump that is verified tripped will be the pump selected with the preferred trip selector switch, 2HS-0352 on 2C02. The selected pump will trip only if both main feed pumps are running. The trip of the selected pump is initiated by a main turbine trip. Both main feedwater regulating valves (HFRV) (2CV-0748 and 2CV-0740) are verified closed on 2C02. The HFRV position indication and
.;f-) > the MFRV controller output should be verified -
V to be indicating ~ 0. Both HFRV bypass valves (2CV-0753 and 2CV-0744) are verified to be positioned - 11 to 15% open on 2C02 (both controller output and valve position). This: valve position will establish ~ 5% of rated main feed flow to the S/Gs. t x, NP84989 SECTION VII - 8.0 PAGE 32
~
bi . ___
,_ b) .Two main condensate pumps operating: .( j .~
Two condensate pumps are verified to be running on 2C02. The main generator lock-out relays will initiate a trip of 2P-2C if 2P-2A is running and a trip of 2P-2D if.2P-2B is running. This will leave only two condensate pumps running, one pump on 2A1 and one pump on 2A2. c) Both heater drain pumps secured: Both heater drain pumps are-verified off 7s on 2C02. Soon after a reactor / turbine trip,
- (a l-the heater drain pumps will trip on either 2T40 low pressure,'2T40 low level or high' differential pressure. If the heater drain pumps have not stopped, the operator should secure them.
d) 'IF'S/G levels decrease'below 46.7%, verify proper actuation of EFW system: . ~ /~N l
- Q'. . WP84989 SECTION VII -'8.0 PAGE 33 b
The Emergency Feed Actuation Signal (EFAS)
- (,_'t '# setpoint is 46.7%. If S/G level (s). decrease below this setpoint, the operator verifies l proper actuation of the EFW system. The EFW System should maintain S/G levels around the EFAS setpoint with no operator action. -Proper EFW actuation is verified as follows:
The operator will. verify both EFW pumps-running. The steam driven EFW pump, 2P7A, starts as soon as EFAS actuates. The motor driven.EFW pump, 2P7B, starts after a 90 second time delay. By verifying proper EFW pump discharge pressure, the operator ensures that the pumps are capable of supplying water to'the S/Gs. By verifying EFW flows', the operator ensures that water-is being supplied to the S/Gs.
- 3) Isolate.MFW and EFW to the affected S/G as follows:
In these steps the affected S/G is isolated and. used as a storage tank.to contain the leakage from the RCS. If both S/Gs have tube leaks, the one with the greatest leakage is isolated. WP84989 SECTION VII .8.0 PAGE 34
~s a) Close MFW block valves to the affected S/G: -f 'i a "A" S/G "B" S/G-2CV-1023-2(2C16) 2CV-1073-2(2C16) 2CV-1024-1(2C17) 2CV-1074-1(2C17) b) Close EFW block valves to the affected S/G: "A" S/G "B" S/G 2CV-1037-1(2C16) 2CV-1039-1(2C16 *,
2CV-1026-2(2C16) 2CV-1076-2(2C1 ) 2CV-1025-1(2C17) 2CV-1075-1(2C17) 2CV-1038-2(2C17) 2CV-1036-2(2C17) c)- IF affected S/G level increases after feed 7- s; isolation, reinitiate S/G blowdown to maintain
's /
level: Instructions are provided to prevent'S/G overfill conditions. Affected S/G level control is very important. Should the_S/G become solid, with RCS pressure above the S/G safety setpoint, the S/G safeties may actuate. EIf the S/G safety valves actuate, an
- uncontrolled release of radionuclides to,the environment would occur.
4 > ,
-t \_. :
WP84989~ SECTION VII - 8.0 PAGE 35
. . -. . - . . = . . - .. .
d) -IF affected S/G-level decreases after feed
- r \ . _
'\ 4 N/- isolation, monitor decrease and do not allow level-to decrease to < 30% wide range until SDC operations are established:
1 Affected S/G level is maintained 2 30% so fthat.should it be necessary to use it for RCS heat removal, it will be available. . Also S/G 1evel is maintained above 30% to ensure cooling of the metal in the affected S/G as.the plant is cooled down to reduce
.the possibility of void formation in'its I
tubes.
. e-4 , G. . Verify containment building integrity:
4 containment integrity is verified in order to main-tain the containment building as a fission product
' boundary.
i- m
- 1) Verify the following containment building para-meters:
1 This step directs the'operatorJto verify that the containment building parameters are being maintained within allowable limits. WP84989 - SECTION VII - 8.0 ' PAGE 36 i
> 2 aw -, , , - ,cw y -ww--- --y,, ,e.-w--rw-v,r-.,y ,m-,-ww- y--- g- - , <- t- + gt v v-- +
ta - - - * - -*' 'g e' -- viv+-- -5 m *-
a) Verify average containment building pres-
- V. sure'is 13 to 16 psia:
Average containment building pressure is verified to be 13 to 16 psia. This value is obtained by averaging the four safety channel containment pressure indications on 2C33 (2PI-5601-1, 2PI-5602-2, 2PI-5603-3 and 2PI-5604-4). Verifying containment building pressure normal ensures that there is no large release of high energy fluid in progress inside containment. b) Verify containment building temperature
~(s) ' ~ $ 140*F:
Containment building temperature is veri-- fied to be $ 140*F. This value can be ob-tained from 2TI-5663 or 2TI-5664 on 2C33 or T-5605-5 or T-5606-6 on the plant or CAPS computer. Verifying containment building temperature normal ensures that there is no large release of high energy fluid in progress inside containment. f-WP84989 SECTION VII - 8.0 PAGE 37
,. - - - . -- ._ - . . . = . _ . . ,, c) Verify the trend recorders en 2C33 OR SPDS
(-) containment display do not indicate ab-normal trelds: (1) Containment Pressure (2) Containment Temperature s (3) Containment Humidity il The trend recorders for containment pressure, temperature and humidity are monitored for abnormal trends. These recorders are 2PR-5601-1, 2TR-5660 and 2MR-5660 on 2C33. The outputs of these recorders may pro-vide the oeprator with indication of
'~
a medium to small primary or secondary fluid leak inside containment.
- 2) IF containment building parameters are abnormal:.
This step provides guidance'to the operator in the event that containment building parameters
.are abnormal.
i .,
. WP84989 SECTION VII - 8.0 PAGE 38
_ . - _ . . . _ . ~
I a) Reverify SGTR symptoms: L)i This step-ensures that the operator did not mis-analyze the initiating event. If a leak to containment atmosphere has occurred, the effects on containment parameters may be delayed. b) Reverify RCS pressure and RCS inventory safety functions (steps-7.C and 7.D of this tab): The RCS pressure and RCS inventory safety _f- functions are to be reverified. These
~
safety _ functions are Steps 7.C and 7.D of this tab. This reverification is an attempt to locate the cause of the abnormal contain-ment conditions.
-c) Monitor .the following parameters -
- 1) CAM (S) radiation
- 2) Containment area radiation monitor (s):
M.- 3) Containment sump level Lj
.WP84989 SECTION VII - 8.0 PAGE 39-
These are primary indications of an 7~I '%s . RCS leak inside containment to the containment atmosphere. This event has similar indications to SGTR, and can be misidentified. Since a change in containment parameters may show a delayed response, they are rechecked at this time. d) Verify containment building cooling fans 2VSF-1A/1B/1C/1D operating with main chill water system operating: (1) IF necessary,_ align SW to containment cooling fans: This step verifies that the containment building cooling fans, 2VSF-1A/1B/1C/
-1D, and the main chill water system are operating. This ensures that the abnormal containment parameters are not due to the loss of the containment cooling fans. If the main chill water system is not operating or is inade-quate, it may be necessary to align service water to the containment /'%. '
cooling coils.
~%)
WP84989 SECTION VII .8,0 PAGE 40 L.
\ '1 r
- If containment parameters indicate that RCS leakage to the containment is *
- occurring, the operator is directed to perform applicable seccions of the *
- SIAS tab in conjunction with this tab.
- GO TO STATEMENT *
- If RCPs are not running, the operator is directed to Step 9 of this tab for *
- guidance in performing a natural circulation cooldown and depressurization *
- of the RCS. *
- 6. Commence RCS cooldown and depressurization to < 500 F (T an ~ l 00 psia as follows:
H g V In the following steps, the operator is guided through an RCS cooldown to < 500*F and depressurization to 1000 psia
.(point below lowest S/G safety valve setpoint) with forced flow'via reactor coolant pumps.
CAUTION *
- THIS CAUTION STATEMENT REMINDS THE OPERATOR TO MAINTAIN AN RCP .
- RUNNING IN A LOOP WITH AN OPERABLE PRESSURIZER SPRAY VALVE TO .
- PROVIDE NORMAL PRESSURIZER SPRAY FLOW. THIS WILL PROVIDE FASTER .
. RCS PRESSURE REDUCTION CAPABILITY DURING THE RCS C00LDOWN AND *
- DEPRESSURIZATION. *
[\ WP84989 SECTION VII - 8.0 PAGE 41
c.-
--] ,_ A) Calculate required shutdown margin for Mortes 3, 4 and
( i 5 as per OP 2103.15 AND borate RCS as required: Adequate shutdown margin for Mode 3, 4 and 5 is veri-fied per OP 2103.15, " Reactivity Balance Calculation". This~ ensures that the reactor will be maintained sufficiently suberitical to preclude inadvertent criti-cality while cooling down and when in the cooled down condition per Tech. Spec. 3.1.1.1. B) Stop one RCP in each loop:
~ .This reduces the heat input to within the cooldown r" capabilities of the SDBCS to achieve maximum cooldown rate. If only one pressurizer spray valve is oper- - ~
able,-preference should be.given to running its associated pump to prevent having to use- the auxi-liary spray valve until cold shutdown conditions. RCS flow should be maintained through the affected-S/G to insure its temperature is maintained equal to 1
.RCS temperature. If'this is'not done, when pres-sure is reduced, voiding could occur in its tubes,-
due to its heat retention capabilities. Preference should be given to running opposite pumps (either "A" and."C" or_"B" and "D").
~ WP84989 SECTION VII - 8.0 PAGE 42
. ' g
,, C) Manually operate an EFW pump (preferably 2P78) to !^~- ), ;, maintain unaffected S/G at ~ 70%:
Unaffected S/G level is maintained at 70% to be used as a transfer medium to remove heat from the RCS. Maintenance at 70% level prevents undesired automatic actuations of EFW system. D) Manually operate SDBCS valve (s) to commence cooldown: The plant cooldown is performed per OP 2101.10, Section 8 while maintaining RCS pressure low to minimize leakage into the affected S/G, yet high enough to maintain a 30* margin to saturation.
- 1) IF main condenser is available, use SDBCS tur-bine bypass valves (2CV-0303, 2CV-0302,
, 2CV-0306): Use of the turbine bypass valves is prefered, so that radioactive nuclides will be contained within the feed and condensate systems. q
.v WP84989' SECTION VII - 8.0 PAGE 43
59.- , t g s W [.-
- 2) IF the condenser is not available, use atmospheric E
;1 -
dump valves from. unaffected S/G.
.p. ,
g}'.
"A" S/G "B" S/G 2CV-1001 2CV-1051 ,, 2CV-0301 2CV-0305 % If equipment failures dictate the use of the atmos-
[J pherie dump valves, the valves from the unaffected ^ S/G .should be used to reduce the release to the environment. If a release is made, the Shift Administrative Assistant should calculate a magnitude of release and make the required notifications per,OP 1903.04. 3)- Do not exceed an RCS cooldown rate of 100'F/hr: This'cooldown limit is. based on Tech. Spec. 3.4.9 to ensure thermal gradients are not imposed that-will exceed' stress limits on the reactor vessel.
. - > components.
- 4) Reset the MSIS variable' trip ~setpoints prior to steam pressure decreasing to within 50 PSIA of'
~
the MSIS.setpoint:~ di , WP84989 SECTION VII - 8.0 PAGE 44-k
r - - 7 t 7 ,, An inadvertent MSIS actuation at this time would LI ) ' not be desirable. Resetting MSIS setpoints is accomplished by depressing pushbuttons on PPS inserts on 2C03 or at PPS panels. E) Commence RCS depressurization to ~ 1000 psia while maintaining an RCS margin to saturation > 30*F: Reduction of RCS pressure to below the S/G safety valves setpoint reduces the possibility of releasing. contaminated steam to the environment. RCS margin to saturation must be maintained at > 30'F to prevent RCS voiding.
.s
- 1) Secure pressurizer backup heaters as necessary:-
This serves to reduce heat input to, the pres-surizer.
- 2) Operate pressurizer spray valves as necessary:
The spray valve for the running RCP (2CV-4651 for A; 2CV-4652 for B) may be modulated open to reduce pressure. If a spray valve is not available, the auxiliary spray valve (2CV-4824-2 on 2C09) may be used. i s_- WP84989 SECTION VII - 8.0 PAGE 45
. r _8
- 3) Do not exceed a pressurizer cooldown rate of 200 F/hr:
This step ensures pressurizer thermal stress limits are not exceeded to comply with Tech. Spec. 3.4.9.2.
- 4) Reset SIAS variable trip setpoints prior to RCS pressure decreasing to within 50 psia of the SIAS setpoint:
An inadvertent SIAS actuation at this time would not be desirable. Resetting SIAS setpoints is. ga accomplished by depressing pushbuttons on PFS
%))
inserts on 2CO3 or locally at the PPS panels. GO TO STATEMENT.
- With RCP's available, Step 9 (natural circulation cooldown) may be elimin- *
- ated, thus the operator is directed to Step 10 for isolating affected S/G. *
- 9. IF RCPs cannot be restarted, a natural' circulation cooldown and depressurization to < 500*F.(T g) and ~ 1000 psia can be
~
performed:
/ i V-WP84989 SECTION VII - 8.0 PAGE 46 L
r
./-
In the following steps the operator is guided through a i
\
natural circulation cooldown to < 500 F and depressuriza-tion to ~ 1000 psia (point below lowest S/G safety valve setpoint). CAUTION .
~. THIS. CAUTION STATEMENT ALERTS THE OPERATOR TO THE POSSIBILITY OF . . REACTOR VESSEL HEAD VOID FORMATION WHILE DEPRESSURIZING THE RCS . *-DURING A NATURAL CIRCULATION C00LDOWN. THE DEPRESSURIZATION SHOULD .
- BE LIMITED TO A RATE WHICH ALLOWS PRESSURIZER LEVEL CONTROL TO BE .
. MAINTAINED. .
A) Calculate required shutdown margin for Modes 3, 4 and f, 5 as per OP 2103.15 AND borate RCS as required:
'u j Adequate shutdown margin for Modes 3, 4 and 5 is verified per OP 2103.15, " Reactivity Balance Calcula-h tion". This ensures that the reactor will be main-tained sufficiently subcritical to preclude inadver-tent criticality while cooling'down and when in the cooled down condition per Tech. Spec. 3.1.1.1.
B) Manually operate an EFW pump (preferably 2P7B) to maintain unaffected S/G lat ~ 70%: Unaffected S/G level is maintained at 70% for use as a heat sink for.the RCS. O
-V 'WP84989- SECTION VII - 8.0 FAGE 47
e-C) Hanually operate SDBCS valve (s)'to commence cooldown:
.:v,(~).-
The plant cooldown is performed per OF 2102.10 Section 8.while maintaining RCS pressure low enough to minimize' leakage into the affected S/G, yet high enough to achieve a 30'F margin to saturation.
- 1) IF the main condenser is available, use SDBCS turbine bypass valves (2CV-0303, 2CV-0302, 2CV-0306):
Use of the turbine ~ bypass valves is preferred, so that-radioactive nuclides will be contained within the feed and condensate systems.
~: -
- 2) IF condenser is not available, use atmospheric dump valves" from unaffec'ted S/G:,
"A" S/G "B" S/G 2CV-1001 2CV-1051 2CV-0301 2CV-0305-s f .
o WP84989 SECTION VII - 8.0 PAGE 48 5
4 If equipment failures dictate the use of the t i N' atmospheric dump valves; the valves from the unaffected S/G should be used to reduce the release to the environment. If a release is made, the shift' administrative assistant should calculate a magnitude of release and make the required notifications per OP 1903.04.
- 3) Do not exceed an RCS cooldown rate of 100*F/hr:
This cooldown limit is based on Tech. Spec. 3.4.9 to ensure. thermal gradients are not imposed that will' exceed stress limits on the reactor g_ -vessel components. V
- 4) Reset the MSIS variable trip setpoints prior to steam pressure' decreasing to.within 50 PSIA of the MSIS setpoint:
An inadvertant MSIS actuation at this time would not be desirable. -Resetting MSIS setpoints is accomplished by depressing pushbuttons on PPS inserts on 2CO3 or at the PPS panels. D) Commence RCS depressurization to - 1000 psia while maintaining an RCS margin to saturation > 30*F: WP84989 SECTION VII - 8.0 PAGE 49
Reduction of RCS pressure to below the S/G safety !(,,J-valves setpoint reduces the possibility of releasing contaminated steam to the environment. RCS margin to saturation must be maintained at > 30 F to prevent RCS voiding.
- 1) Manually operate the pressurizer auxiliary spray valve 2CV-4824-2 as necessary:
With no RCPs operating, use of the auxiliary spray valve will be required. a) Do not exceed a pressurizer cooldown rate f'- of 200*F/hr: d-This step ensures that pressurizer. thermal stress limits are not exceeded'in compliance with Tech.= Spec. 3.4.9.2. b) Reset _the SIAS variable trip setpoints prior to RCS pressure decreasing to within
- 50 psi of_the SIAS setpoint:
ub . WP84989- SECTION VII - 8.0 PAGE 50
] ; ' em
1 An inadvertant SIAS actuation at this time
; would not be desirable. Resetting SIAS setpoints is accomplished by depressing pushbuttons on PPS inserts on 2CO3 or locally at the PPS panels.
c) IF the pressurizer and charging water temperature difference is > 200*F, complete . Attachment "A" of OP 2103.05 for each spray cycle: This ensures compliance with Tech. Spec. 5.7.1, component cycle stress limits, by-recording each spray valve cycle, u f~s)
- 2) During depressurization, monitor for reactor
~c vessel head void formation. Indications of-void formation are:
The following guidance is provided for the operator. in regard to reactor vessel head. void formation. The same symptoms exsist and actions are appro-E priate for void formation in the affected S/G i: tubes. Void formation is not desirable as control of RCS pressure is reduced. The below listed indications are based on the shifting of! water
.,~,
(
.WP84989 SECTION VII - 8.0 PAGE 51 ~ ~ ^ ^
,5 . volume in the RCS from the vessel head causing 'S .]' abnormalities in pressurizer. level control and indications.
a) Pressurizer level increases significant1y'
^
greater-than expected while operating auxiliary spray: As RCS pressure is decreased below the saturation pressure for head area temperature, a bubble is being formed in the head area (or. idle S/G tubes). Water displaced by this void fills the pressurizer causing a level increase.
.b) Pressurizer level decreases while operat-ing charging pumps: ,
With charging pumps operating and letdown restricted (in manual) or isolated, RCS pressure will increase. This increase in pressure shifts the' water from the pressurizer to the voided area as actual pressure exceeds the saturation pressure for voided-area temperature.
. ;,~ 'i(_
WP84989 SECTION VII - 8.0 PAGE 52 s u t.
s . s.- c) Letdown ficw unexpectedly greater than
. . .f'N. '\'J charging flow. IF the pressurizer level control sy.' tem is in automatic:
This is an indication of " excess" water in
, the RCS which could be from a void being formed. If pressurizer level is constant this water could be being displaced by a void being formed. ,, 3) If a reactor vessel head void is indicated:
If a void is formed in the reactor vessel head, c4 depressurization continues until pressurizer s_, level reaches Technical Specification upper limits (82%) or RCS subcooling margin decreases
~
to a lower operational limit (30'F). The philo-sophy forothese' actions is that the reduction. of leak flow by depressurization-of the RCS is of primary importance. - Vendor engineering
~
analysis suggests that as long as control is maintained'during formation of the reactor vessel head void, no serious. problems will be caused by allowing the void to form. The following steps provide guidance to the opera e
' WP84989. SECTION VII - 8.0 PAGE 53 I..
s _g tor in maintaining the void in a controlable
- t' condition.
a) Isolate letdown. b) Continue depressurization to ~ 1000 psia OR until pressurizer level indicates 3 82%. c) IF pressurizer level increases to 3 82%: (1) Stop RCS depressurization. (2) Repressurize RCS until pressurizer level stops decreasing. (3) Repeat depressurization and repres-surization until RCS pressure is 73 ~ 1000 psia: V Should either limit be reached (82% pressurizer level or 30 F subcooling), the depressurization is stopped, the RCS repressurized and water volume replaced in the RCS by charging and isolation of' letdown as the vessel head void is collapsed. Depressurization is reinitiated when pressurizer level is returned to nominal levels. This process is repeated until the desired RCS pressure is achieved (1000 psia). 6 By alternating between depressurization and
, pressurization, cooler water is forced into s
k v WP84989 SECTION VII - 8.0 PAGE 54
. A*
i
,s the void to cool down the area, thus eliminating i \# the void.
- 10. When RCS pressure is reduced to ~ 1000 psia and RCS temperature is < 500'F, isolate all flow paths to and from the S/G with the ruptured tube:
Once depressurization to a value below the steam line safety valve setting and cooldown to an acceptable margin to saturation has been accomplished, isolation of the affected S/G is commenced.
'l NOTE l j) _ l This note reminds the operator to isolate the S/G with the highest leakage, l V
l if both S/Gs have indications of tube leakage, and continue RCS heat removall l with the.unisolated S/G. l A) Close or verify closed the following valves on the affected steam generator:
"A" Steam Generator 2CV-1010-1 Main Stm Iso. 2C17 2CV-1040-1 Main Stm Iso Bypass. 2C17 2CV-1000-l' 2P7A Stm Supply 2C17 2CV-1016-1 Blowdown Isol 2C17 2CV-1024-1 MFW Block- 2C17 2CV-1038-2 EFW Block 2C17 2CV-1025-1 EFW Block 2C17 3CV-1037-1 EFW Block 2C16 2CV-1026-2 EFW Block 2C16 3CV-1023-2 MFW Block 2C16 2CV-1001-1 Upstrm Atmos Dump 2CO2 2CV-1015 Blowdown Isol 2CO2 2SV-1152 B/D Sample 2C116 2SV-1151 Steam Space Sample 2C116
(~'} 2SGS-1042 MSIV Trap Iso .w' 2N5-74 Kain Stm. Trap Iso 2NB-43-1 Main Stm. Trap Inlet WP84989 SECTION VII - 8.0 PAGE 55
li 2MS-43-2 Main Stm. Trap Bypass ^ ;Q[^'i , 2MS-2102 upstream Atmos. Dump Trap Iso.
"B" Steam Generator-2CV-1060-2 Main Stm Iso. 2C16 2CV-1090-2 Main Stm Iso Bypass 2C16 2CV-1050-2. 2P7A Stm Supply 2C16 2CV-1073-2 Upstrm Atmos Dump 2C16 2CV-1039-1 EFW Block 2C16 2CV-1076 EFW Block 2C16 2CV-1066-1 Blowdown-Isol 2C17 2CV-1074 MFW Block 2C17 2CV-1036-2 EFW Block 2C17 2CV-1075-1 EFW Block 2C17 2CV-1065 Blowdown Isol. 2C02 .2SV-1162 B/D Sample 2C116 2SV-1161 Steam Space Sample 2C116 2SGS-1045 MSIV Trap 2HS-2102 Upstream Atmos. Dump Trap Iso Valves are listed t'o guide the operator in isolation of only the. affected S/G. The. unaffected S/G should be left lined up to be used for cooldown.
C) B) Maintain an indicated wide range level in the affected'S/G AND maintain steam pressure < RCS pres-sure:
~ ~ &&though the intent of' isolation"is to " bottle up" ~
the -affected S/_G,' a n'd to'use it as a storage tank for ' the additional reactor coolant'that escapes during , the remainder of the plant cooldown and
-depressurization,. total ~ isolation is not always , possible or advisable.
f
'b /N .
k/ '
,WP84989 SECTION VII - 8.0 PAGE 56 c
.,_s Level in the affected S/G should be maintained N# between 30% and 90% on the wide range level indication. A' minimum level of 30% (wide range) should be maintained to provide a means of transferring heat from the isolated S/G to the'RCS.
Forced RCS flow through an isolated S/G will provide adequate heat transfer to maintain the isolated S/G's temperature approximately the same as the operating S/G's temperature, if level is maintained above 30%.
, , With no RCPs running, there will be little or no natural circulation flow through the isolated S/G and its associated loop, leaving these components in a "(~s.[ ~ h'ot stagnant condition. A hot isolated S/G presents V
a problem'when trying to depressurize the RCS. p. 3 Depressurization of the RCS below the isolated S/G's l' saturation temperature could cause voiding in the-e tubes and other portions of the stagnant RCS loop. This would cause the voided portions of the loop to act as'a pressurizer and delay the RCS depressuri-zation to shutdown cooling entry conditions. vn M' A maximum' level;of 90% (wide range) should be maintained to prevent overfilling the isolated S/G-
- /; from the RCS via the tube rupture. S/G overfill presents th'e possibility of. lifting a S/G safety
_,- \ N_] ' A.. WP84989 SECTION VII - 8.0 PAGE 57
'E
F
' 'l . $.
valve, damage to main steam line piping, or ry
% JJ ' valve / component failures.
The affected S/G pressure should be maintained f slightly less than RCS pressure and also below the S/G safety valves lift setpoint. This will minimize
, the . loss of primary ' fluid to the S/G secondary side, J '
minimize potential releases of radiation to the d- . environment, and the loss of RCS inventory. This
~
will also_ preclude secondary fluid from diluting the RCS system.
~- '
i,; Options are given in the following step to control 4-~q r the'affected S/G level, pressure and temperature, is-) /
- :11 ,, "_I_F the condenser is available, steam the
- 1) .
affected S/G by opening the HsIV. bypass valve t
;Q 11' AND using SDBCS turbine bypass valvesi.
ii n,.
'r ?y 3e .This' removes the maximum amount of energy t (pressure).from the S/G.
a pp (p. - 2)) Drain ~the affected S/G;using the blowdown systems. I This will~ reduce level and to some extent pres-V. sure and still retain the contaminated water
//2 within the plant systems.
(j}- 4
'NP84989 SECTIO?! VII - 8.0 PAGE 58 s
MVc :e
rj - . a ~
, j;, 3) IF the condenser is not available, steam the c
affected S/G using the upstream atmospheric dump valve: This is the least desirable of the options avail-able to reduce pressure or level, as it provides a release to atmosphere. a./
- 11. Cooldown and depressurize the RCS to SDC system entry conditions:
With'RCS temperature at < 500' and pressure at - 1000 psi,
-the operator is directed to perform a cooldown using the fj s . unaffected S/G. -It will be necessary to cooldown, ?w):
depressurize and drain the systems below the level of the leak to stop leakage.
.A) Cooldown and depressurize as per OP. 2102.10: .OP 2102.10 " Plant Shutdown and Cooldown" contains detailed' instructions for plant cooldown. Only the unaffected S/G-is used for_cooldown. The affected a .-
S/G will act as an additional heat source increasing , _ theLheat loa'd on-the unaffected S/G. This may limit cooldown rate. NJ '
. , WP84989- SECTION~VII - 8.0 PAGE 59 I
g d v
' ^ -E b: ;.a P,- ~ !! I .. ' N- x B)' Continue to maintain an indicated wide range level-in the affected S/G-AND maintain steam pressure less than_RCS pressure -
,e f ;y The_affected S/G level is maintained should it be _necessary to use it for RCS heat removal and to. ensure it is cooled down. p C) IF -natural circulation cooldown is being performed,
; ~ continue monitoring for reactor vessel head void m .
formations e i . .c ff g, Continuous monitoring for void. formation per step 9.D.2 ' - (,j ':.
~
, , is required. The RCS is highly susceptible to tvoiding
. in this condition. If reactor' vessel head voiding is 4
indicated, step 9.D.3 providesfguidance to collapse t-the void if.it restricts natural circulation flow. k 4 D) IF necessary,= establish radiation control areas, in:
- any affected= regions (i.e., S/U and B/D, dis, turbine . building sumps, etc.): -
T + ju . n ,' This step _ serves to remind the' operator _of radiation N' hazards present in normally clean systems. .These
~
- p. 'should be' treated as contaminated systems.~ Further
'IWP84989 .SECTION VII --8.0 PAGE 60 b'
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" g. .
1 guidance is given in OP 2203.15, which deals with ,
-- , l reducing and controlling contaminated fluid in the-w- - ; turbine building. support systems.
s + 112. ;When-.the RCS is cooled to ~ 120 F'and RCS pressure is i ~
--50 psia, drain the affected S/G AND drain the RCS to the S/G tube maintenance levels The leak through the S/G tube will continue until the plant -is 'depressurized and the RCS is drained below the level of the. leak. This~ step instructs the operator in reduction of RCS' temperature and pressure after shutdown cooling has ~
i
~~
_ been placed in service and to drain below the 1e'ak level. ,(.
'M- * . A) . . Drain;the affected S/G using the blowdown system to ~ . , the S/U and-B/D DI system: ~
The steam generator'is-drained through.the SU/BD DI' [_ ., system.- The DI will remove most radionuclides from
;.. the. waterf thus reducing its activity' level. 'The .
.. ,DI resins may then be handled as radioactive waste.in ( ~
~the regenerative waste' solidification system. It is
,q desirable _at this time to line up floor drains in=this' area from-the turbine building to the auxiliary p , h, ^'
; building.
[ JWP84989 ~ 'SECTION VII.- 8.0 PAGE 61 r . g.
- = .'
n T -B). - When the affected S/G has been drained, collapse the [\.
- g 'h-[? .
pressurizer steam bubble AND drain the RCS to the S/G tube maintenance level as per OP 2103.11: OP 2103.11, Draining the Reactor Coolant System, provides _ guidance.to the operator in draining the RCS. -Once the RCS has been drained below the leak, the leak should stop. s k K):
.J . ^--
I gr- ,
'\~ .
- WP84989 SECTION VII - 8.0 PAGE 62' L.
9.0 STEAM GENERATOR TUBE RUPTURE GREATER THAN CHARGING PUMP CAPACITY
%) .
RECOVERY ACTIONS 9.1 Operational Goals The primary operational goal of the Steam Generator Tube Rupture (SGTR) Greater than Charging Pump Capacity Recovery Tab is to prevent the release of radioactivity to the public and to l minimize the spread of contaminated liquid while placing the plant in a stable condition. This goal is generally achieved by , the performance of the following:
- 1. Verification of safety function controls l-
- 2. Identification of the affected steam generator (S/G)
- 3. Cooldown and depressurization of the RCS to below the lift >
e pressure of the S/G safeties ,' (] 4. Isolation of the affected S/G , v
- 5. Continued cooldown of the RCS to reach shutdown cooling (SDC) conditions.
9.2 Description of SGTR Greater than Charging Pump Capacity , l' Entry into this tab requires the condition that the reactor has
' tripped. - Prior to - the reactor trip, the operator will be performing the steps associated with the "SGTR Within Charging l Pump Capacity" tab. Since placing the plant in Mode 3 does not terminate this accident, this tab directs the operator through cooldown and depressurization and into draining operations.
For the major portions of the above operations, the operator is ' directed to the procedure which covers them. 1 (~') m p.* WP84989 SECTION VII'- 9.0 PAGE 1 h
F I
.f ,) In order to protect the health and safety of the public and to '"'~
minimize contamination of the secondary system, the operator
'should take appropriate measures to control the transfer of radioactivity from the affected S/G. These measures include i isolation of the affected S/G and avoiding the use of main steam safeties or the atmospheric dump valves on the affected i side unless absolutely necessary. This leak differs from the classic LOCA in that the back pressure from the S/G opposes ,
flow, somewhat minimizing the flow rate. However, in a LOCA the leak will either be in containment or isolated on an SIAS i signal, whereas in a SGTR the reactor coolant which has leaked into the S/G can exit containment via the steam lines. t 9'-i Steps should be taken to prevent overfill of the affected S/G
'\ ,] .
throughout this tab, but especially during the time period {-
~during which the RCS pressure is > 1000 psia. Lifting of the ,
9 S/G safety valves or use of the atmospheric dump valves provides , I a direct release path to the environment. Raising S/G pressure to the lift setpoint of the S/G safety ^ valves could be accomplished i in two ways: by RCS heat transferred to the S/G or by RCS leakage into the S/G. _ Reducing RCS temperature below 500 F reduces the possibility of lifting a safety valve, since the saturation pressure of the RCS is below the lift pressure for the lowest set safety valve (1078 psig). The second process has a built-in time delay. The pressure drop across the tube keeps the S/G from seeing high RCS pressure until the S/G fills )
~I')
G sufficiently to drive S/G pressure up.
~ WP84989 SECTION VII - 9.0 PAGE'2 4
o
m;- .
! s 3
s.
. 22 1 'l <
- There are two NRC concerns associated with S/G overfill. The
}.. ~
S/G~ safety valve's are not designed to relieve or " pass" water.
- v. . If'a safety valve: passes water, damage to the valve and its
~ '
seating surface could result in the valve not rescating, thus '
~ ~ .providing a path for uncontrolled release. The second concern h
- is the main steam piping hangers. These hangers are not designed l ifor: the support of water filled piping. Maximizing blowdown
;a.
from the affected S/G combined with' drawing off steam should take care'of.an overfill condition. If, however, an overfill 3y _ s condition'is imminent (S/G' level 2 90%) steps may'be taken to l prevent the S/G from " going solid" and possibly discharging [;'r , ' ~
-water via the steam safeties. One step would be to increase .lthe steaming rate via the turbine bypass valves (not to exceed '
RCS cooldown limits). The increased steaming will affect both . E
~ -S/Gs,'since the main steam piping is' cross connected. If level -
y in the affected S/G is still rising, consideration should be' T-given to' shutting the MSIV on the unaffected S/G. This step ,,
.. - 3 would shift'all steaming to the a'ffected S/G which should lower p' ',
I
'its level. When the operator-has reached an RCS-. temperature'of .< 500*F~and a pressure of ~ 1000 psia, this-tab directs him to-isolate the'affected S/G. The operator should ensure that the unaffected S/G MSIV is'open prior to shutting the affected S/G .MSIV. This will-ensure-that at least one S/G is available for q- >
1 .
, RCS cooldown'.. If both of the S/Gs are found to be leaking, the one with the larger. leak is' treated as the "affected" S/G. 'l <. I
{- i p J - p / ,
' WP84989'.. ~SECTION VII'- 9.0 PAGE 3- .* l a, f . r
-m Achieving the maximum cooldown/depressurization rate is of
(~ ) paramount importance in mitigating the consequences of this
-accident. The leak from a failed tube cannot be isolated.
Minimizing the pressure differential between the affected S/G I and the RCS will help reduce the amount of leakage through the failed tube. However, the need to maintain 2 30'F margin to i saturation should take precedence over the goal of bringing primary pressure to a point slightly above S/G pressure. Continued RCP operat4cn is a topic of concern for the operator I during a SGTR. It is d.esirable to maintain two RCPs operating (one in each loop) during this accident. This gives the operator more control using mairc pressurizer spray to cool down and ' f'] depressurize~the plant and results in the continuous mixing of . v fluid in the reactor vessel head, thus minimizing void formations l in the head. Additionally, forced circulation provides better. mixing in the reactor vessel downcomer/ lower plenum regions , I thereby minimizing pressurized thermal shock concerns. l Maintaining two RCPs running is desirable, Lut not a necessity l in this casualty. If no RCPs are running, a natural circulation cooldown may still be performed. What is a necessity is power to at least one of the ESF busses (2A3/2A4). There will be no RCS makeup capability until power is restored or an emergency makeup pump is installed. Until makeup capability is restored, no cooldown should be performed, because of inventory loss out 1
,7 8 ,]
WP84989. SECTION VII - 9.0 PAGE 4 i
m~ ,. 4 y k
) ~
of theiruptured tube and shrinkage ~due to cooldown. Also there "l): f( q ?. _
^ - Lare no boration capabilities for attaining SDM.
L- . s t
~
Once makeup capability is regained, a cooldown may be commenced. Ifthe. operator [hasregainedatleastoneofthe-ESFbussesbut
.l, has not regained an off-site power source, consideration should i be given to' restoring power to one of the instrument air (IA) ~ ~
compressors _as per the " DEGRADED POWER"= tab. Without IA, an. r !
.RCS cooldown would be difficult in that the operator would have to manually adjust the atmospheric dump valves in order to stay . +
within the cooldown limits. There is also a possibility of a
+ , high radiation, areaI in the vicinity of the atmospheric' dumps.
i When off-site.powertis restored, re-energization of the '
/ i >
components necessary for main condenser operation is an .;.
' s_ 1 1..>. , important step in minimizing'the release via the atmospheric =[
dumps of radioactive or-contaminated st'eam.
. i.
ii fi
- During a. natural circulation cooldown,. voiding may occur in the - reactor vessel head. :During a: rapid natural circul'ation , . cooldown, a bubbleLin the' head will almost certainly be formed.
This tab provides the operator with instructions to secure y;. , depressurization-if pressurizer level increases't'o 2 82%. Repressurizing with the heaters or opening of the reactor j
. vessel head vents are'the-steps provided to shrink or decrease ~
f,
. the bubble so that depressurization-may be reinitiated.
Voiding in the affected S/G's tubes may also occur if no steam
~
1i n; '.-.'
'.-Q) ;
9 WP84989.< SECTION VII - 9.0 PAGE 5
. i.
- u g { d
js~ - is being drawn off the affected S/G. The affected S/G would be
'",1 -
- g. acting as'a hea; source.to the unaffected S/G. The safety functions are verified to ensure that a LOCA is not happening concurrently with this event. If a LOCA is also in progress, i-applicable portions of the "SIAS" tab are performed in conjunction l.
with this tab. j-9.3 Safety Functions Affected The safety functions affected by this accident are RCS , inventory control, RCS pressure control, and possibly RCS heat removal. A SGTR Greater than Charging Pump Capacity will result in the I emptying of the pressurizer. The length of time that it will o qN 'N be empty is dependent upon the size and magnitude of the tube
-L) rupture. With a large rupture, RCS pressure should decrease .
below the shutoff head of- the HPSI pumps allowing them to inject water into the RCS and restoring an indicated level in ,: t-the pressurizer. This action will restore both RCS inventory and_RCS pressure control. ! The RCS heat removal safety function is affected later in this tab when the affected S/G is isolated. As long as the unaffected S/G is capable of removing heat from the RCS, it should not be a problem. If the affected S/G is not cooled down along with the RCS, voiding of the S/G U-tubes could occur . during natural circulation cooldown. 1
- h.
t t
%,)
WP84989 SECTION VII - 9.0 PAGE 6 ( hm
a 73 9.4 Major Parameter Response A) Reactor Power . A reactor shutdown vill be initiated by the insertion of the CEAs'. A rapid decrease in reactor power and a negative startup rate will be observed. This rapid decrease in reactor power will be followed by a steady l decrease in indicated power until the suberitical
. multiplication level is reached.
B) RCS Temperature The RCS temperature remains relatively constant until the i reactor trips. Following the reactor trip, the RCS hot and cold leg temperatures will decrease to approximately
- i the hot standby values, if the RCPs are running. If the l
/~j- /
RCPs are stopped, RCS temperatures are expected to , stabilize near hot zero power values with hot leg I te.nperature greater than cold leg temperature with natural , a circulation flow established. , t C) Pressurizer Pressure and Level This accident will result in the emptying of the pressurizer. I When pressurizer level decreases to less than 29%, both banks l of proportional heaters and the backup heaters that are selected to automatic will b'e de-energized. As the primary system pressure decreases due to the loss of inventory and the heater de-energization, the leakage will decrease due to the reduced differential pressure between the primary and the secondary. If this decrease is enough to reduce i [~l
/
the leak to within the charging pump capacity and depending WP84989 SECTION VII - 9.0 PAGE 7 ;
~ -.+ z - i (w g SL[
- 1 -.
', ., upon the~ amount'of time it takes for RCS pressure to be P-G(v" . . . ' reduced to within the shutoff head of the HPSI pumps, safety tinjection water may or may_ not be injected into the core. If this happen's, . it will take longer to recover both pressurizer level indication and pressurizer heater control.
- l D) . . Steam Generator Pressure Initially, both S/Gs should rise to saturation pressure
(~ 1000 psia):for the RCS hot zero power temperature, and be maintained at that pressure by the SDBCS; system. Eventually, the'affected S/G cculd fill solid and equalize
.l 4
with RCS pressure.
.t .-
- E) . Steam-Generator. Level
>. e, Following the~ reactor trip, the level'in both S/Gs will .[
r shrink to the usual post-trip level. After that, level 6" , .will slowly rise in both S/Gs due to main feedwater (MFW) -
- 4 and emergency _feedwater (EFW), and due to the tube leak'in ,'
q the affected S/G. If'the rupture is,large enough, and' '
,l i:
especially after the affected S/G has been isolated, level
' may increase enough~tc fill the'affected S/G. - - .F) Radiation Detection Instrumentation -
Thf5 instrumentation will provide indications of S/G tube leakage. The' main' condenser offgas radiation monitor would 2
' probably be' the- first . to alarm.. The-S/G sample cooler -radiationmonitorsandthemainsteamlineradiation i monitors would indicate which S/G had the tube leak-2 A
- l. l-
- WP84989.-
'SECTION VII - 9.0. PAGE 8 i
s
+ ' 5 ;j, l .( '?' g L
g,, 9.5' Bases for SGTR Greater than Charging Pump Capacity Recovery Actions t
\'~)
Verify the reactor is shut down: STEP 13 ! This step addresses the safety function of reactivity control by. ensuring that trip signals to selected l sets of reactor trip circuit breakers (TCBs) have l-been received and verification that the reactor is
'shutdcwn. For all emergencies, ensuring the reactor !
is shutdown and maintaining it shutdown, thereby reducing the amount of heat generated in the core, 15 minimizes the consequences of the event. A) Verify appropriate sets of TCBs are opens- '
.(~j x-This addresses the proper operation of the -[
breakers upon receipt of a RPS trip signal or , manual-trip signal and ensures that power to all ,, l-CEAs is interrupted. An appropriate set of TCBs
.is defined as any combinatior. that will de-energize ll i,
both CEA power panels (2C70 and 2C71). [ B) Verify all CEAs are fully inserted: i This step ensures adequate shutdown margin (SDH) ? (Technical Specificaton 3.1.1.1) to ensure that r the reactivity transients associated with i. iO il
" WP84989 SECTION VII - 9.0 PAGE 9 l'
F l postulated accident conditions are within t. f acceptable limits. Calculations (per Procedure [ 2103.05, " Reactivity Balance Calculations"), ensure adequate SDM with one CEA stuck at the i withdrawn position. Therefore, if two or more l CEAs are not inserted after a reactor trip, the j reactivity control safety function is not to be considered satisfied, since a SDM of 5% cannot be immediately assured. GO TO STATEMENT
- This statement directs the operator to perform the " EMERGENCY REACTIVITY * '
- CONTROL" tab in conjunction with this tab when he receives indication that *
'] .
- two or more CEAs have failed to insert. Entry into this tab will provide *
- guidance on options to de-energize TCBs (if necessary) and will direct the * '
- cperator to commence emergency boration to establish adequate shutdown * ,
I
- margin.
******************************************************************************* 9 l
C) Verify reactor power decreasing: l Verification of reactor power decreasing by available instrumentation ensures nuclear characteristics response is as expected, i
'WP84989 SECTION VII - 9.0 PAGE 10 i
b
^
o
'[' ' STEP-2: Verify proper response of.the electrical system: l Verifying proper response of the electrical system ensures that the vital auxiliary power safety function is' maintained. Improper response of the ;
electrical system could affect numerous succeeding l p j -
-safety functions. Electrical power must be present -
to have the instrumentation and controls necessary to
- i satisfy the succeeding safety functions. ;
i
-A) . Verify the turbine is tripped This ensures that the major source of heat
- removal from the RCS has been removed. The turbine trip also initiates electrical system *
()T t,_ - transfers. Failure of the turbine to trip could' challenge several safety functions, such as: reactivity control, vital auxiliary power, RCS. pressure control, and RCS inventory control' An. uncontrolled RCS cooldown, due to the failure of the turbine to trip, could result in ESFAS , actuations (i.e., SIAS, MSIS), and a potential for pressurized thermal shock (PTS) exists.
- t i
l
'"N ! %_-) . WF84989 SECTION VII - 9.0 'PAGE 11 m_. ____._._.._._a_._____
c:-
~ -~s
_l) Verifying all turbine control valves OR all i '. V< i turbine stop valves are closed ensures that steam is secured to the HP turbine thus preventing overcooling of the RCS and
- possible overspeeding of the turbine.
l-
- 2) Verifying all turbine intercept /stop valves I are closed ensures proper turbine trip actuation and prevents a possible turbine ,
overspeed condition. I B) Verify generator output breakers (5130 and 5134) AND exciter field breaker are open on panel _2C01: This step ensures proper electrical isolation of _(~} w-the turbine generator and prevents motori:ing .] the main generator. , P
-i C) Verify that all 6900V, 4160V and 480V buses are -
energized from an operable startup transformer ! This ensures that a proper electrical transfer has beer. made. Failure of the electrical buses to properly transfer may mask indications of safety function status and may affect methods of 4 ( ) -
\ j' WP84989- SECTION VII - 9.0 PAGE 12 i
L
o { , ges4 control. Two particular electrical problems are
!'~I addressed: Degraded Power and Blackout. No . attempt has been made to give guidance on loss of individual buses, except for Step 1) below, since each occurrence will be unique due to the I
load variations on each bus. i
- 1) IF a bus fails to transfer AND there are no bus lockout alarms, one attempt to re-energize that bus should be considered if required I.
loads-are powered from that bus. If a bus lockout alarm is present, determination and correcticn of the cause is required before '
~.{~~ re-energization of the bus. .
s 1 t, l I l l 4 , . f~h
- x. J
~
\ l WP84989 SECTION VII - 9.0 PAGE 13 i t.
L p,4 .*******************************************************************************
)i *' ~GO TO STATEMENT *
- This statement directs the operator to perform the " DEGRADED POWER" tab in *
- conjunction with this tab. The operator should review both tabs during the *
- span of the casualty. He should ensure that any steps out of both tabs *
{
'
- that could mitigate the effects of this compound casualty have been *
'
- performed. With at least one emergency diesel generator supplying one of *
- the 4160 volt ESF busses, RCS inventory should not be a problem. RCP *
- operation is desirable, but not necessary. Regaining the support systems *
-* -for condenser operation is important, because until the condenser is * \'
- restored for normal use the only heat removal path available is the *
- discharge of radioactive steam to the environment via the main steam safety
- n
- valves or the atmospheric dumps. * ,'
r"$ *******************************************************************************
'(s-) I - l.:
ii t.
.s i
f3
.ss/
WP84989 SECTION VII - 9.0 PAGE 14 i I
GO TO STATEMENT *
- This statement directs the operator to perform the " BLACKOUT" tab in *
- conjunction with this tab. The operator should review both tabs during the *
- time period of this dual casualty. Regaining either of the ESF busses *
* (2A3 or 2A4) supplied by one of the emergency diesel generators is of *
- extreme importance in mitigating the effects of this compound casualty. *
- No cooldown should be attempted until power to one of the ESF busses is *
- regained, because no RCS makeup capabilities are available to allow *
- boration for SDM or makeup due to leakage through the ruptured tube and *
- shrinkage due to cooldown. *
)
STEP 3: Verify " permissive" handswitches for atmospheric dump valves are in the "0FF" position: This step ensures that no radioactive steam is released to the environment due to automatic actuation of the atmospheric dump valves.
,A WP84989 SECTION VII - 9.0 PAGE 15
~ --. .. . . . _ _ . _
f (: '~
' ' 4' A -
I-j 'ql .
. STEP 4: - When RCS pressure $ 1766 psia, verify SIAS~ actuation:
y-r j= If RCS pressure decreases to 5 1766 psia, proper
>s . automatic actuation of-SIAS components should be verified. 'If proper actuation has not occurred,
- l. :
-manual actions should be taken to insure proper- ll system operation.
i A) Indicating lamps for SIAS actuated components correspond to the color of the switch name plates: 1:
- 1) Red - Valve open or equipment running. .!
'i
- 2) Green - Valve shut or equipment stopped. F
\- - '
This step ensures proper component alignment for ]t r
-SIAS actuation. .n
!~ p B)- Verify HPSI injection flow'when'RCS pressure
< 1450 psia -1 Two of the three HPSI pumps should have auto i
started (after a 10-second time delay). HPSI pump shutoff head is 1450 psia so once RCS pressure is less than 1450 psia, HPSI flow.should r be noted on the flow meters. , t V
, ~ .
i _) I I
'SECTION VII - 9.0 ~ , WP84989 PAGE 16 j'^! i si
_ , _ . _ . . _ _ _ _ _ __ _ . _ _ _ . _ _..__.____._.._._____.____._m. _ _ _ _ . _ _ _ . _ _ _ _ _ . _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ . _ _ _ _ _ _ _ _ . _ _
. ._ - . - . . ~ . . . - - . - . - . . . _ . . . ~ . . ~ - . -
s t-- . c -- , i f. l C)^ Verify letdown is isolated: w,A Letdown automatically isolates upon receipt of SIAS. This is done to minimize RCS inventory I / loss. l
... l D) Verify. maximum charging flow on 2FIS-4863 on s
Panel 2C09: All three charging pumps receive a start signal i on SIS actuation. Two out of the three should always be aligned for operation. The charging pumps will inject concentrated boric acid from ,' the BAM tanks. They have a 50-second time delay y
-on auto start. i l
i
, e f,
I h.
- \} . .
WF84989 SECTION VII - 9.0 PAGE 17 i
i
/-s g- . . STEP 5: Verify RCS inventory / pressure control c: ' Q) ~
'74 .......................................................................
- CAUTION .
. DO NOT OVERRIDE HPSI COMPONENTS'UNLESS THE RCS MARGIN TO SATURATION .
l
. IS 2 30*F.. . .l . IF THE RCS MARGIN TO SATURATION DECREASE To s 30*F, RE-ESTABLISH . . MAXIMUM HPSI FLOW UNTIL 2 30*F MARGIN TO SATURATION EXISTS: .
l
. THIS CAUTION IS INTENDED TO PREVENT THROTTLING OF HPSI MOVs TO . . MAINTAIN PRESSURIZER LEVEL IF THE RCS IS NOT SUBC00 LED. .
O' .. -: (_/ A) Verify pressurizer level is being restored to [ 2 29% but s 82%: f. Maintaining pressurizer level 2 29% should allow .. I use of the pressurizer heaters while avoiding
-damage due to uncovered heaters. The upper f.
limit of 5 82% is provided to meet the l requirements of Technical Specification 3.4.4. The. bases for this requirement is to ensure that a steam bubble is maintained in the pressurizer to accommodate pressure surges. r-l
. iq ^
r-L) IlP84989 SECTION VII - 9.0 PAGE 18 6
y ..
- ^- _ ,.
, .c m M 4 ~.
L ; /~5 , _
' .1) When pressurizer level is restored to 2 29% !
Vi?s.J . ' but s'C2%:- 4 r 1 8 k .c) Stop/ start charging pumps as necessary. to maintain level. jj UJ sf ';i AND/OR '
+ l 4
b) override and throttle HPSI cold leg h.l injection valves as necessary to maintain levels i As RCS pressure decreases below 1450
. psia, HPSI flow will increase. When '
makeup ~ flow (HPSI and charging) becomes greater than the leakage from the
'(N - ruptured tube, RCS inventory should -Q increase and pressurizer level indication should be regained. Once level is
[ regained, the above steps will allow j the. operator to maintain pressurizer I level between 29% and 82%. B) Stabilize RCS pressure at a value as low as
- possible which allows maintaining the RCS margin j to saturation 2 30*F:
e h
+
1 .
~ .
WPS4989 SECTION VII - 9.0 PAGE 19 i b [
r Maintaining RCS pressure as low as possible will ,
- p. decrease leakage out of the ruptured tube due to a decreased differential pressure between the RCS and the S/Gs.
- 1) IF necessary take manual control of pressurizer heaters:
a) IF pressurizer level decreases to
< 29%, all pressurizer heaters in auto will be de-energized by interlock.
- 1) Restore pressurizer level > 29%.
- 2) Place the pressurizer proportional heater handswitches to "0N" to
) regain control of the proportional heaters.
- 3) Place the pressurizer backup heater handswitches to "0FF" AND back to "AUT0" OR HON" to regain control of the backup heaters:
The above steps inform the operator what happens to the pressurizer heaters when level decreases to < 29% and also how to regain control of the heaters once level > 29% has been regained. i WP84989 SECTION VII - 9.0 PAGE 20 w.
.I jN 2): -IF RCPs are running, take manual control of \ J' ,
pressurizer spray valves as necessary: This is the preferred method for depressuri-zation of the RCS.
- 3) IF RCPs are not running, take manual control of auxiliary spray valve as necessary:
'With RCPs secured / there is no motive force to furnish flow through the normal pressurizer spray. valves (2CV-4651 or 2CV-4652). The charging pumps discharge will have to be used for RCS depressurization via the h.v .
auxiliary spray valve. Shutting of the normal charging valves (2CV-4827-2 and . 2CV-4831-2) will increase the auxiliary spray flow. a) IF the pressurizer and charging water
. temperature difference is 2 200*F, ,
complete Attachment "A" of OP 2103.05 for each spraying cycle l 1
's,_.)
WP84989 SECTION VII - 9.0 PAGE 21 e 1- -
s When using the auxiliary spray valve,
^
a
. finer pressure control may be obtained by throttling 2CV-4651 or 2CV-4652 open and allowing auxiliary spray flow to be diverted back through the normal spray line to the loop. This also will minimize the number of spray nozzle thermal cycles by-eliminating the need to cycle the auxiliary spray valve. If the difference between pressurizer and charging water temperature is > 200'F, as measured by pressurizer, water phase temperature
( )' (2TI-4622) and regenerative heat exchanger to RCS temperature (2TI-4825), then logging of each spray cycle is required to ensure Technical Specifica-tion (5.7.1) is met. r s, I WP84989 SECTION VII - 9.0 PAGE 22
;L: Y
- /m, '
STEP 6:- Verify core heat removal by monitoring the following
- (, f , ,
parameters: This safety function addresses circulating cooling fluid in the preferred state around the core to remove decay heat. Core heat removal is ensured by
- verifying RCPs running (RCS flow), RCS margin to saturation > 30'F ~ (subcooled fluid) and core exit thermocouples (CETs) relationship to Figure 2.
eeeeeeeeeeeeeeeee.eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee...e
* , CAUTION. =
4
'e IF A PRESSURIZER SPRAY VALVE IS INOPERABLE, DO NOT STOP THE RCP e N A e-ASSOCIATED WITH THE OPERABLE SPRAY. VALVE: * - V . e e THISSTATEMENTREMINDSTHEOPERAT0kTOCHECKSPRAYVALVE e =e OPERABILITY BEFORE SECURING ANY RCPs. e eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee s
r A 3 i
.t N
U
'FP84989 SECTION VII - 9.0 PAGE 23 j\ .i. . . . . - , ~ , , - - , 4..---- - - - - . , ,_.,,.w_-.,~.,,- - - - + . - - - . , ,- ~,--+e.---,-- --- ve------ -----n-,v-,---- -
O ".\ .
, s .= 9 e .i
.g ,
>(
[~Ms .A) RCS Flow:
, -QI. , '
m 1)' WITH symptoms of a SGTR, maintain two RCPs +-
.,,; 7 j j' ,
operating (one in each loop) regardless of
- margin to saturation conditions
9.; ,, [ _t i Maintaining two RCPs operating will provide , n .; the operator better control using normal $ip;s.A
- 4. { 14 5-pressurizer spray to cooldown and depressurize
, o c the RCS. It will also provide for a continuous mixing of fluid in the reactor eg[ vessel head and S/G tubes, thus minimizing We, .
T)E void, formation. Np . ,M3 ig 1/ 4
- 2) g pressurizer pressure decreases to AJ,g
'B ' g/ .s 1400 psia secure two RCPs (one in each loop): '1O 1; i .v- ,, ~
This step ensures that two RCPs are secured for any' sizable.depressurization event.
^
p.. < Prior to securing-th'ese two RCPs, the v 3 operator should verify the other two pumps.
, i. .. . sM operable. This.would entail checking RCP ;?? - vi ;5( .
amperage'and AP indication on the selected . $. . . . ,W RCPs to verify.that they are actually ny y ' ^1f, y"' ' circulating fluid in the RCS.
.; : ,x, 1% -
r.
.\ /J- u , v, , z.,
y. n;'N i...WP24989~ - SECTION VII - 9.0 PAGE 24
~ < , _ ). s'~ f Y g:
ig~ygp:;;.. ur u - . , .
;DI ' =
(^;s- .-
- .N
i 7[m: ~ 3) IF the RCPs are not running: n:
^^ =a) Verify RCP, restart criteria satisfied ^ . per. Appendix H, AND ~ b) Attempt to start one RCP in a loop l
with an operable spray valve first. l THEN c) Attempt to start one RCP in the opposite , loop In the above steps, the operator is b I directed to reinstate forced flow with RCPs to enhance core cooling. If only one RCP can be restarted, the one with ; y'~y an-operable spray valve should be .
\/
started to provide. normal spray flow. .l.
~
Flow through the unaffected S/G is 1 ,. -required as a heat sink. Flow through ' t
-the affected S/G is required to
- preclude voiding in-its tubes during a !-
cooldown=and prevent the affected S/G Il
~ ~
from acting as a heat source.due to
.its large volume of heated vater.
s c 1
)
u f O
'k
- /~,.
; n 'SECTION VII - 9.0
, WP84989 PAGE 25 1 - l- ,i
x
,3 4) IF RCPs cannot be started, verify natural t ' ~ '
circulation as follows: Should RCPs not be available, natural i circulation may be utilized for core cooling. Guidance is given in the following steps'to l verify natural circulation has been established. a) Hot leg temperatures (T h) have i stabilized or are slowly decreasing. b) Cold leg temperatures (T ) have c e stabilized or are slowly decreasing l jb' .
. a u-Hot leg temperatures (T } "" "
h '9 temperatures (Tc ) should stabilize and may - slowly decrease. This indicates that the t AT.has increased enough to establish'the , I required-flow to remove the decay heat
- being produced. ' These indications.of T and {
h T are assuming a relatively consta'nt S/G l
. pressure is being maintained. l s
I
.. y A
- WP84989 ~ SECTION'VII - 9.0 PAGE 26 i
s
}s c) ..RCS AT h(T - Tc ) is less than 50'F:
w< e RCS AT (T h. - Tc ) should be less than 50 F. Actual testing and experience have shown that a AT > 50 F is l abnormal and may indicate that natural j circulation flow rate is degraded. d) No abnormal difference between CETs and hot leg RTDs: l No abnormal difference between CETs and hot leg temperatures should f) ~. exist. If CET temperatures increase
- k.J much above T , natural circulation h
flow may be insufficient.
'f 1
e) Continuous demand for EFW flow to f maintain.censtant steam generator level. i l-f) Continuous demand for the operation.of the SDBCS_ valve (s) or S/G safety valves to maintain a constant S/G 8 pressure: I
)-'s . > N ,l: ' ' WP84989 SECTION~VII - 9.0 PAGE 27 t
a
L
'73 If the S/Gs are functioning as a heat \./ '
sink for the RCS, there will be steam flow from at least one location. If steam is released from the S/Gs, feedwater must be added to maintain level. li B) Verify RCS margin to saturation is 2 30'F: The margin to saturation 2 30* ensures the i reactor coolant is maintained subcooled while
. allowing for possible inaccuracies and uncertainties of the margin to saturation ,] } calculators and their inputs. Circulating a subcooled fluid is the preferred method of i I
removing core decay heat. , i 1). IF RCS margin to saturation is s 30'F, monitor core exit-thermocouple's relationship .1 to Figure 2. l
~
- GO TO STATEMENT *
'
- This' statement directs the operator to the " INADEQUATE CORE COOLING" tab.if *
- Laverage CET' temperature is not within the limits of Figure 2.
- I
,r'X ,
A.2
~ WP84989 SECTION VII - 9.0 PAGE 28 .t , _ =.
k 7s . -STEP 7: Verify RCS heat removal capability: k): The removal of heat from the RCS is necessary to
, maintain long-term core heat removal. The following steps are provided to ensure Mai flow is available to the SGs. l A) Verify SG levels are being maintained.
- 1) MFW system operating in " Reactor Trip Override" (RTO).
I
- 2) Two main condensate pumps operating:
The FWCS reacts to a reactor trip by generating '
-l) . an RTO signal. This signal closes both MFW . %.J regulating valves, reduces the remaining MFW l' pump speed to minimum and adjusts MFW bypass valves to maintain ~ 5% flow demand. This 5% ..
I flow demand is ~ 11 to 15% bypass valve position and controller demand output. !
-3) Both heater drain pumps' secured:-
The heater drain pumps are tripped.on an SIAS signal. If not stopped, the operator should secure them.
;--s.
- ..( ,
)~
lWP84989' SECTION *121 - 9.0 PAGE 29
e
,_s . 4) . IF S/G levels decrease below 46.7%, verify 'V proper actuation of EFW system:
This step directs the operator to verify ' the EFW pumps (2P-7A and 2P-7B) start and their associated valves operate to maintain l S/G. level at - 46.7%. The steam driven pump (2P-7A) will start immediately, while , the electric feed pump (2P-78) has a 90-second time delay. I J I'
-l NOTE l [ ' l This note reminds the operator to isolate the S/G with the highest leakage, l ~(~~} -l. if both S/Gs .have indications of tube leakage, and continue RCS heat removall ['
I l with the unisolated S/G. l f.
- B) Isolate feed to and steam supply.to 2P-7A from the affected S/G as.follows: ' l2 1.
In these steps the affected S/G is isolated and used as a-storage tank to contain the leakage from the RCS. If both S/Gs have tube' leaks, the one with the greatest leakage is isolated. o
- ' /~T
(-f WP84989. SECTION VII - 9.0 PAGE 30 it i- 1 _
--,-,2---. - .. - .
7 ts
~ ^. . ,1 1) Close MFW block valves to the affected S/G:
l' "A" S/G "B" S/G k. 2CV-1023-2 (2C16), 2CV-1073-2 (2C16)
--2CV-1024-1 (2C17) 2CV-1074-1 (2C17) ~
i
.2)- 'Close EFW block valves to the affected S/G: . "A" S/G "B" S/G )
i
, 2CV-1037-1 (2C16) 2CV-1039-1 (2C16)
- 2CV-1026-2 (2C16) _2CV-1076-2 (2C16) 2CV-1025-1 (2C17) 2CV-1075-1 (2C17)~
2CV-1038-2 (2C17) 2CV-1036-2 (2C17) .
- 3) Isolate steam to 2P-7A from the affected S/G.
"A" S/G "B" S/_G_
2CV-1000-1 2CV-1050-2 1. i. This step will. assist in minimizing the
- 5 release of radionuclides to the environment.
cf'! lss
- 4) -][F affected S/G level increases after. feed
~
F isolation: . . I-a) Maximize S/G blowdown to maintain ~an indicated. level l
.This step' instructs the operator to l s increase-blowdown from the affected S/G. . t_
t
. ,4 ; ? h ~s . - , ?WP84989- SECTION VII - 9.0 PAGE 31 i
t N. :
e- . b) IF necessary, maximize steaming-rate
~t ~
via turbine bypass valves: An increased steaming rate via the l' . turbine bypass valves will draw off I.
, both S/Gs equally. If an overfill 1:
condition is imminent (2 90%), consideration should be given to , shutting the MSIV on the unaffected S/G to shift all steaming to the
-1 affected S/G, thus lowering level, e
- 5) IF affected S/G level decreases after feed
([]' w-isolation: a)' Isolate blowdown. ~ '
"A" S/G "B" S/G 2CV-1015 2CV-1065 .-
t 2CV-1016-1 2CV-1066-1 b)- . Monitor-S/G level" decrease and do not f. allow it to decrease to s 30% wide. ; j range. indication until SDC operations i ' are established: I ? 4 --
) - -s WP84989 -SECTION VII - 9.0 PAGE 32 I
k bc:
. . - - .3 s.
r-s This step instructs the operator to b, maintain at least 30% wide range indication in the:affected S/G to ensure proper level for natural circulation flow. Maintaining this level will also ensure cooling of the .i metal in the S/G to prevent' tube voiding. ,
- - STEP 8: Verify containment building integrity:
I Containment integrity is verified in order to 6 maintain 1 the containment building as a fission l i(h
< \-./
product boundary.
'1 A) Verify the following containment building .
t parameters: _ ..
,- .l.
This step. directs the operator to verify that' o 4 the' containment building parameters are being. R
-maintained within allowable limits.
D e
=
{u , se et
' WP84989- -SECTION VII - 9.0 PAGE 33 i
o
% 1
i 7 ~i . '1) Verify average containment building pressure Lj is 13 to 16' psia: Average containment building pressure is i' verified to be 13 to 16 psia. This value is obtained by averaging the four safety l channel containment pressure indications on 2C33 (2PI-5601-1, 2PI-5602-2, 2PI-5603-3 and 2PI-5604-4). Verifying containment building pressure normal ensures that there- h i: is no large release of high energy fluid in f
,, -progress inside containment.
i. 2). Verify containment building temperature is
< 140'F: -j i
containment building temperature is verified - , I to be.s 140'F.. This value can be obtained from 2TI-5663 or'2T-5664 on 2C33 or f.
'T-5605-5 or T-5606-6 on the plant or CAPS computer. Verifying containment building temperature normal ensures that there is no .large release of high energy fluid in progress inside containment.
1 1( . WP84989' .SECTION VII -.9.0 PAGE 34 i
2 0: 4
^a j .c o - -3) Verify the following trend recorders on t ,)'
2C33 OR SPDS containment display do not indicate abnormal trends: a) Containment Pressure b) Containment Temperature c) Containment Humidity i e
.The trend recorders for containment pressure, temperature and humidity are monitored for abnormal trends. These recorders are l
2PR-5601-1, 2TR-5660 and 2HR-5660 on 2C33. + The outputs of these recoders may provide the operator with indication of a medium to f' .small primary or secondary fluid leak inside containment. i
?
B) _I_F containment building parameters are -abnormal: This step provides guidance to the operator in. ~l the event that containment building parameters
.l are abnormal. .I
- m g
'.\
WP84989 SECTION VII - 9.0 PAGE 35' i E?
- 1 ?
g 4 , Af 1
' -y- ~y . 1) Reve'ify r SGTR symptoms: ~.k,_/ s This step ensures that the operator did not misanalyze the initiating event. If a leak 4 'to containment atmosphere has-occurred, the . , ' effects on containment parameters may be 'l delayed.
- 2) Reverify RCS pressure and RCS inventory safety functions:
The RCS pressure / inventory safety function is'to1be re-verified. These safety functions l
- are Step 5 of'this procedure. This
} , .
re-verification is an attempt to locate the- -
- (;
cause of the abnormal. containment conditions. ,,
~ .I o
- 3) Monitor:the following parameters: J g.
a) -CAM's radiation ~l A b) Containment area radiation monitors c) . Containment sump level-I' _ The above parameters are indications of a 2LOCA inside containment. An increase in- ' these-parameters.would indicate a LOCA'in-
' conjunction with the SGTR. I- ;,s .
4.. ) y 4 n - WP849C9'- - l-SECTION VII - 9.0 PAGE 36 I b Y4 i
c-- . . , r-
' v. . ,
2
's g qi i
- 4) ~ Verify proper operation of containment Ls -; .
cooling system: N , ,
~ ' a) '2VSF-1A/1B/1C/1D operating:
qq: , All four containment cooling fans auto
/
start on CCAS after a 40-second' time delay.
^
b) Service water outlet valves open u _ (2CV-1519-1 and 2CV-1513-2): These valves'-receive an open signal on l
-~
CCAS. The inlets.(2CV-1511-l'and
}
2CV-15-2) are normally left open but they also receive an open signal on. CCAS. [ c) -Bypass dampers open: Upon1 receipt of CCAS,'the containment
.a cooling fan bypass dampers automatically open. .This' bypasses the normal suction air ducts and chilled water' cooling coils for increased air flow through the SW coils.
SECTION VII
$WP84989. '9.0 PAGE 37 9 N
/,_,)
GO TO STATEMENT *
- This. statement directs the operator to perform applicable portions of SIAS *
- tab _in conjunction with this tab is the operator has indications of a LOCA *
~
L* inside containment.
- GO TO STATEMENT *
- If a natural circulation cooldown is required, the operator is directed to *
- Step 10'of this tab. *
~
(~T STEP 9: IF RCPs are running, commence a RCS cooldown AND Q,1 depressurization to 5 500 F THand ~ 1000 psia: In the following steps, the operator is guided through a cooldown to s 500*F and depressurization to
~
a point below the lowest S/G safety setpoint with forced flow via the RCPs.
,- -s*
h
\_/ ~WP84989 -SECTION VII - 9.0 PAGE 38 o
A
2 e
- . L4 . A') Calculate required SDM for Modes 3, 4 and 5 as As ,]'
per OP_2103.15 AND borate RCS as required:
. This step ensures that the reactor will be maintained subcritical while cooldown is in . . progress.
B) Verify two RCPs operating (one in each loop). A RCP operating each loop will provide normal spray flow for depressurization and heat removal from the affected S/G.
"Ef')) C) Manually operate an EFW pump (preferably 2P-78) %)
to maintain unaffected S/G at - 70%: 2P-7B is regarded as the preferred pump because it is electric driven, while 2P-7A is steam l. _ driven. Manual operation of EFW valves is required to raise.the unaffected S/G'lavel to
- 70% to provide an adequate heat sink for RCS heat removal.
s I h ,$
- x/- ,
WP84989- SECTION VII - 9.0 PAGE 39 I k -
r , . , .
- :1
- s l l
~
l a a t' p .,.# hQ'r < D)l Manually operate'SDBCS valve (s) to commence
, ()f , ~ . .cooldown:
The plant cooldown is' performed per OP 2102.10, I! Section 8, while maintaining RCS pressure low to
- . l;l minimize leakage into the.affected S/G, yet-high 1), ~
enough to achieve a 30'F margin to saturation. t e
- 1) =IF, main condenser is available, use SDBCS turbine bypass valves (2CV-0303, 2CV-0302, 2CV-0306):
s Use of the turbine bypass valves is.
~ 's preferred, so that radioactive nuclides ,
_ , . will be contained within the feed and -
~ . condensate systems.
i
- 2) IF condenser is not available, use :,
' atmospheric dump valves from unaffected ~ -S/G: "A" S/G "B" S/G 2CV-1001- '2CV-1051 ~ '_L- . .
2CV-0301 2CV-0305' [ 'y ' . I { ~,1; ' m 4WP84989' . LSECTION VII - 9.0 PAGE.40
-i
E l t
~
a _-j s If equipment failures dictate use of the t V L./ " atmospheric dump valves, use of valves from unaffected S/G should be used to reduce the release to the environment. If a release is made, the Shift Administrative Assistant
. should calculate a magnitude of rel' ease and make the required notifications per OP 1903.04.
- 3) Do not exceed an RCS cooldown rate of 100*F/hr:
This cooldown limit is based on Technical Specification 3.4.9 to ensure thermal
)
gradients are not imposed that will exceed. stress limits on the reactor vessel components..
- 4) Reset the.MSIS variable trip setpoints.
prior to steam pressure decreasing to within 50 PSIA of the MSIS setpoint: An inadvertent MSIS actuation at this time
- l. -
would not be desirable. Resetting MSIS setpoints is accomplished by depressing pushbuttons on PPS inserts on 2C03 or at ()
%s the PPS panels. + s.
WP84989 SECTION VII - 9.0 PAGE 41
E) Commence RCS depressurization to ~ 1000 psia while maintaining an RCS margin to saturation 2 30 F: Reduction of pressure to below the S/G safety valves setpoint reduces the possibility of releasing contaminated steam to the environment. RCS margin to saturation must be maintained at 2 30 F to prevent RCS voiding.
- 1) Secure pressurizer backup heaters, as necessary:
g~ q~ , This serves to reduce heat input to the pressurizer.
- 2) Operate pressurizer spray valves as necessary:
The spray valve for the running reactor coolant pump (2CV-4651 for A; 2CV-4652 for B) may be modulated open to reduce pressure. If a spray valve is not available, the auxiliary spray valve (2CV-4824-2 on 2C09) may be used. 1 WP84989 SECTION VII - 9.0 PAGE 42
- 3) IF necessary, throttle HPSI injection flow:
^
v Upon commencing depressurization, throttling HPSI flow may be necessary to reduce RCS pressure and minimize the AP between primary and secondary systems. Maintaining a small AP will minimize RCS leakage through the ruptured tube during cooldown.
- 4) IF necessary, stop/ start charging pumps:
This step is provided to minimize the AP between primary and secondary.
- 5) Do not exceed a pressurizer cooldown rate of 200 F/hr:
This step ensures pressurizer thermal stress limits are not exceeded to comply with Technical Specification 3.4.9.2.
- GO TO STATEMENT *
- This statement directs the operator to go to Step 11 of this tab if RCPs *
- are operating. Step 10 may be omitted.
- WP84989 SECTION VII - 9.0 PAGE 43
~~ l STEP 10 IF RCPs cannot be restarted, a natural circulation .V- -cooldown and depressurization to s 500 F (T #"
H
^ , ~ 1000 psia can be performed: * . CAUTION .
- THIS CAUTION STATEM$NT ALERTS THE OPERATOR TO THE POSSIBILITY OF .
. REACTOR-VESSEL HEAD VOID FORMATION WHILE DEPRESSURIZING THE RCS . . DURING A NATURAL CIRCULATION C00LDOWN. THE DEPRESSURIZATION SHOULO .
- BE LIMITED TO A RATE WHICH ALLOWS PRESSURIZER LEVEL CONTROL TO BE .
- MAINTAINED. .
~ (~} A) Calculate required SDM for Modes 3, 4 and 5 as L%J per OP 2103.15 AND borate RCS as required:
This step ensures that the reactor will be maintained suberitical while cooldown is in progress. B) Manually operate an EFW pump (preferably 2P-7B) to maintain unaffected S/G at ~ 70%: 2P-7B is regarded as the preferred pump because
-it is electric driven, while 2P-7A is steam
_(~j v
, WP84989. SECTION VII - 9.0 PAGE 44
/
gr-), driven. Manual operation of EFW valves is u_/- required to raise -the unaffected S/G level .to P
~ 70% to provide an adequate heat sink for RCS ' heat removal. 'C) Manually operate SDBCS valve (s) to commence cooldown:
The plant cooldown is performed per OP 2102.10,
-Section 8, while maintaining RCS pressure low to minimize. leakage into the affected S/G, yet high enough to achieve a 30*F margin to saturation.
L
- 1) IF main condenser is available, use SDBCS
- v(( .
turbine bypass valves (2CV-0303, 2CV-0302, 2CV-0306): Use of thel turbine bypass valves is preferred, so that radioactive nuclides will'be contained within the feed and condensate systems. Y l_/ x '
' WP84989 SECTION VII - 9.0 PAGE 45 L .
T w; , ,. ;_ 'l ,
' ~ " "' ~ , ';;; 1_ t 4.' L. = , yh[ ' =
2)' IF condenser is not available, use
':%); *f~~, . atmospheric dump valves from unaffected S/G: "A" S/G "B" S/G
'; ~ 2CV-1001 2CV-1051' 7,.95 '
%" 2CV-0301 2CV-0305 v, . ~ , If equipment failures dictate use of the w
1 atmospheric dump valves, valves from unaffected S/G should be used to reduce p;. - the release to the environment. If a 4 5 < - y : release is made, the Shift Administrative n ,
' Assistant sh'uld o calculate a magnitude of reie'ase and make the required notifications ~ / per OP 1903.04.-
, _.: Y
.. 3)' .Do not exceed an RCS cooldown rate of 100'F/hr:
This cooldown limit.is based on Technical' Specification 3.4.9 to ensure thermai
~
gradients are not imposed that will exceed stress limits on the reactor vessel
< 7 components.
l 8 r
..m o
A )'. 1
'WP84989- , SECTION VII-- 9.0 PAGE 46 d' .
t
r._ _ ( > p. y. Reset the MSIS variable trip setpoints j j-q . 4) V: prior to steam pressure decreasing to. within 50 PSIA of the MSIS setpoint: An inadvertent MSIS actuation at this' time
. . 'would not be desirable. Resetting MSIS setpoints is accomplished by depressing pushbuttons on PPS inserts on 2CO3 or at =
the PPS panels. D) Commence RCS depressurization to ~ 1000 psia while maintaining an RCS margin to saturation 2 30'F:
- r. . <"s Reduction of pressure to below the S/G safety 4 .
' valves,setpoint. reduces the possibility of releasing contaminated steam to the environment.
- . - RCS margin to saturation must be maintained at s
2 30'F to prevent:RCS-voiding. a <
~
- l. Manually operate the pressurizer auxiliary spray valve, 2CV-4824-2, as necessary:
7 b 1 p i ,{
) d s.s e
, t 4 WP84989~ SECTION VII - 9.0 PAGE 47
~
7-q If more auxiliary spray flow is needed, shut the (' ' ' normal charging isolation valves (2CV-4827-2 and 2CV-4831-2). If less auxiliary spray flow is needed, throttle open the normal pressurizer spray valves (2CV-4651 and 2CV-4652). a) IF the pressurizer and charging water temperature difference is 2 200*F, complete Attachment "A" of OP 2103.05 for each spray cycle: This temperature difference is measured at the pressurizer water phase temperature (2TI-4622) versus the regenerative heat
-' /"'i exchanger to RCS (2TI-4825). Logging of O
each spray cycle is required to ensure
. Technical Specification 5.7.1 is met.
1). IF necessary, throttle HPSI injection flow: Once the operator has commenced depressurization, throttling of HPSI flow may be necessary to reduce RCS s pressure and minimize the amount of reactor coolant that leaks out of the primary into the secondary systems.
- v 1
WP84989 SECTION VII - 9.0 PAGE 48
s
= ,f ,
s . . 12 ) IF necessary stop/ start charging pumps: A_): + The operator will need to cycle charging pumps to provide auxiliary spray as 7 required for depressurization of the primary and to assist in pressurizer level control.
- 3) Do not exceed a pressurizer cooldown
,_ rate of 200 F/hr:
This step ensures that pressurizer thermal stress limits are not exceeded l : ('j - ' to comply with Technical Specification v '. 3.4.9.2.
- 4) During depressurization, monitor for 1
reactor vessel ~ head void formations o The-following guidance-is provided for the operator in regard to reactor vessel head void formation. The same symptoms exist and actions are appropriate for void' formation in the affected steam generator tubes. . Void. 3 WP84989 SECTION VII - 9.0 PAGE 49
. W s
4 3G .
> 4 }/LN formation is not desirable as pressure Af control is reduced. The below listed indications-are based on the shifting yo of water volume in the RCS from the vessel head causing abnormalities in t
pressurizer level control and indications. a) - Indications of void formation are: Pressurizer level increases significantly greater than expected while operating auxiliary spray:
!%-4 As RCS pressure is decreased below the saturation pressure for head area . temperature, a bubble is being formed in.the head area (or idle S/G. tubes).
Water displaced by this void fills the. pressurizer causing a level increase. v.
$1.
S
/
LQ) .
-WP84989- SECTION'VII - 9.0 PAGE 50
. ~
f b) Pressurizer level decreases while a
~ operating charging pumps:
With charging pumps operating and letdown restricted (in manual) or
. isolated, RCS pressure will increase.
This increase.in pressure shifts the water from the pressurizer to the voided
~i area as actual pressure exceeds the r
saturation pressure for voided area temperature. t
- 5) IF a reactor vessel head void is
- - f-~ indicated:
.8 -
F a) Continue depressurization to ~ 1000 psia or until pressurizer level indicates 2 82%: ? The reduction of the leak flow by depressurization of the RCS.is-of primary importance. As long as the bubble does not grow so large as to.
's ' interfere with natural circulation, the ? '
w /;
' WP84989 SECTION VII-- 9.0-. PAGE 51 g y
- 4 u m ;. ' y. ,-~q . operator should continue depressurizing 4../
toward 1000 psia. The 82% pressurizer level depressurization stopping point is the Technical Specification upper
- o. , limit on pressurizer level.
b) IF pressurizer level increases to 2 82%: Sk 1
\
l Stop RCS depressurization: 1)
.s Stop depressurization by either shutting ~
the auxiliary spray valve (2CV-4824-2) or by opening one or both of the
~ ;1(] .' normal spray valves (2CV-4651/2CV-4652).
K r:
?:
- 2) Repressurize RCS until pressurizer s,; _z,, level stops decreasing:
Energize the pressurizer heaters and-leave them energized until level stops decreasing and pressure starts ' increasing.
*\- } _.
_k, s i. t v
' X, / - , WP84989.
yl .SECTION VII - 9.0 PAGE 52 s-
; h t. ?' d
N
+ + ,
jcs ' 3) Repeat depressurization and repressuri-t ,) zation until RCS pressure is ~ 1000 psia: e Continue in the manner described above
, until RCS pressure is reduced to .~ 1000 psia. '4) ;IF necessary, operate reactor vessel ;
head vents: [ If the vessel head bubble cannot be controlled by repressurization,- indicated , by pressurizer level holding constant-
'e and/or. disturbances in' natural circulation 3
flow indication, open the reactor vessel. head vents (2SV-4668-1/2SV-4668-2)-
'and vent the head tofeither_the quench tank via-2SV-4669-1 or to the containment o atmo'iphere via'2SV-4670-2.
4
~ STEP 11: When'RCS pressure is reduced to ~ 1000 ps'ia and RCS . temperature is s 500*F, isolate all' flow paths.to and , v . .
i from.the S/G'with the ruptured tube: 4 4 ., _ f . . w WPB4989 - SECTION VII - 9.0 PAGE 53
+ + -e r 4 e v - - , - - , . , - 4,.w , , , , , . , , _ ,.m.--,..vy, -,w,,,w-y-,4,m.g,,,,.y.,-,,,.%.. , , , .#, wry,,-,,--y-.,.y-- -,--....,.py-,_.,~., , - , ,,.y,,,,
( w w l co-. ' J g. i ,
; \~d - ;l NOTE- l l]IF both S/Gs have indications of tube leakage, this note instructs the -l ~ 'l operator to ' determine Lwhich S/G has the highest-leakage, isolate it, and l l1 continue-heat' removal wiih the-least affected S/G. This will minimize the l J '
Ll' release o'f contaminants. l A) . Verify that the MSIV on the unaffected S/G is open prior to isolating the affected S/G: s, s. t
.If the unaffected S/G MSIV was shut earlier in 'this accident to maximize the steaming rate on the 'affected-S/G, insure it is re-opened prior ~ s dT m to shutting the affected S/G MSIV. This ensures l sy)T ' , s -that at least one S/G is available to be used in cooling down. ~
B) -Close or_ verify closed the.following valves on-
,k _
the'affected S/G: l '
"A" S/G 2CV-1010-1 Main Stm. Iso. 2C17 1
2CV-1040-1 Main Stm. Iso. Bypass 2C17 _, 2CV-1000-1 2P-7A Stm. Supply. 2C17 2CV-1016-1 . Blowdown Iso. 2C17 2CV-1024-1 MFW Block 2C17 90 ' 2CV-1038 EFW Block ,2C17 E ,
-2CV-1025-1 EFW Block 2C17 g~ J3CV-1037-1 EFW Block 2C16 ." ,- '2CV-1026-2 EFW Block- 2C16 s, its a >
!. g y . u -
]WP84989 SECTION VII'- 9.0 PAGE 54 ,e
.. 2CV-1023-2 MFW Block 2C16'
{7-(jf; 2CV-1001 Upstrm. Atmos. Dump 2C02 2CV-1015 Blowdown Iso. 2C02 2SV-1152 Blowdown Sample 2C116 2SV-1151 . Steam Space Sample 2C116 2SGS-1042 MSIV Trap Iso. Main Stm. Trap Iso. 211S - 7 4 - 2MS-43-1 Main Stm. Trap Inlet 2MS-43-2 Main Stm. Trap Inlet 2MS-2102' Upstrm. Atmos. Dump Trap Iso. l 1
"B" S/G ' ~ -2CV-1060-2 Main Stm. Iso. 2C16 2CV-1090-2 Main Stm. Iso. Bypass 2H6 '
2CV-1050-2 2P-7A Stm. Supply 2> ' 2CV-1039-1 EFW Block 2C19 2CV-1076-2 EFW Block 2Ca6 2CV-1073-2 MFW Block 20.6 2CV-1066-1 Blowdown Iso. 2C;7 _l 2CV-1074-1~ MFW Block 2C17 2CV-1036-2 EFW Block 2C17 2CV-1075-1 EFW Block 2C17 2CV-1001 Upstrm. Atmos. Dump 2C02
- 2CV-1065 Blowdown Iso. 2C02 '
j u . 2SV-1162- . Blowdown Sample 2C116 2SV-1161 Steam Space Sample 2C116 , b- 2SGS-1045~ MSIV Trap Iso. 2MS-2102 Upstrm. Atmos. Dump Trap Iso. l i The above mentioned valves will isolate both the water supply to and the steam from either S/G. l C)- Naintain an indicated wide range level in the I affected S/G AND maintain steam pressure s RCS -
, pressures ! 'Although the intent of isolation is to " bottle up" the affected S/G and to use. it as a storage tank for the additional reactor coolant that .
I WP84989 SECTION VII - 9.0 PAGE 55 T- i
7, .; . escapes during' the remainder of the plant cooldown and depressurization, total isolation is not always possible or advisable.
. i, Level in .the affected S/G should be maintained l- .between 30% and 90% on the wide range level j indication.. A minimum level of 30% (vide range) should be maintained to provide a means of 1 transferring heat from the isolated S/G to the RCS. ~ Forced RCS flow through an isolated S/G will provide i
adequate heat transfer to maintain the isolated S/G's temperature approximately the same as the operating S/G's. temperature, if level is maintained above 30%. ' m
- U j With no RCPs running, there will be little or no -
natural circulation flow through the isolated S/G and r its associated loop, leaving these-components in a ,. hot stagnant condition. A. hot isolated S/G presents a problem when trying to depressurize the RCS. Depressurization of the RCS below'the isolated S/G's saturation temperature could cause voiding in the tubes and other portions of the stagnant RCS loop.- This would cause the voided portions -of the loop to act as a pressurizer and delay the RCS depressuri-zation to shutdown cooling entry conditions.. I As
- WP84989 SECTION VII - 9.0 PAGE 56 i
4
~_ l f <
- i. -
A maximum level of 90% (wide range) should be
'"?,o .t ~
maintained to-prevent overfilling the isolated S/G
.~
from'the'RCS via the tube rupture. S/G overfill presents the possibility of lifting a S/G safety I
~~ , valve, damage to main steam line piping, or Il! -valve / component failures. =i The affected S/G pressure should be maintained slightly less than RCS pressure and also below the ~
S/G safety valves lift.setpoint. This will minimize t .. I the loss of primary fluid to.the S/G secondary side, minimize potential releases'of radiation to the i environment, ar.d the loss of-RcS inventory. This ' f/~"p -will also preclude secondary fluid'from diluting the , N# ; LRCS system.
.r-t.
Options are given-in the.following step to centrol p
. the affected S/G level, pressure and temperature. ~
l-
- 1) IF the condenser is available, steam thef l
affected S/G by opening.the MSIV bypass
-valve AND using the SDBCS t'urbine bypass-valves:
I []3 t
- L WP84989 .SECTION VII - 9.0 PAGE 57 i
u -e 3 {.'. s
' W -
y-43= Steaming the affected S/G will prevent
.' ~N,) , . , overfill and reduce S/G pressure. It would also prevent the possibility of S/G tube , +
voiding.
- x:
-- 2). Drain the affected S/G as necessary using
- the blowdown system:
This step provides the operator with an alternate way to maintain S/G level and pressure.
- 3) .IF the condenser is not available, steam-r
[($;' the affected S/G using-the upstream . qj. atmospheric dump valves-
. LIf S/G' level 'nd a pressure are increasing, - 4 use'.of the upstream atmospheric dump valve may be necessary. It will be a release of. , . radionuclides, but it will prevent overfill, and damage to the steam safeties and main steam line piping'and hangers.
4 h ' if . l WP84989 -SECTION VII - 9.0 PAGE 58 , __ ?' s
p , , . .. . _ ..._ . __ _ . _ _ _ . _ _ _ . _ . _ _ . _ _ . . . . _ _ _ _ . . . _ . . _ . - . _ _ . . . _ . _ . _ r s f
~ ..;ty ,
j 0 2
- .: ~
- j;, +
$ji D)- ' Initiate actions of OP 2203.15 to prevent the-Blh'~4 ' ' ' '
-F .,
spread of' contamination: i w . . This procedure provides the operator directions
, on.how to reduce and. control contaminated fluid ~
in the turbine building support systems.
~
w s STEP'12: ~ Cooldown'and depressurize the RCS to SDC entry
- 1 conditions:
, r The.following steps provide instructions on how to - cooldown and depressurize from 500*F, 1000 psia to 300*F, 300 psia for Src entry.
i.1
' A). HPSI system operation may be terminated if all of.the following conditions are mets
- 1) 4RCS is at least 30'F subcooled:
This condition ensures that the reactor e coolant is capable of removing heat from
~ ^
the core
.AND
,u-f { ' - WP84989 _ SECTION VII - 9.0 PAGE 59 f L a f.; h- ,
t
.w .w Pressurizer level is 2 29% but s 82% and 2)
N. ' ' being controlled by automatic or manual operation of the pressurizer level control system: This condition ensures that the RCS leak
~ rate has decreased enough that charging-pump operation can maintain pressurizer-level between 29% and 82% before tenminating HPSI operation.
AND
- 3) At least one S/G is available to remove heat from the RCS:
- /3 9 () -
, This condition ensures that RCS heat removal s .
capability is available prior to terminating HPSI. Lil
~ B) Cooldown-and depressurize per OP 2102.10, Section 8.0:
This procedure provides the operator with the steps required to perform an uncomplicated cooldown. r q. N. ) - s
'WP84989f SECTION VII - 9.0 PAGE 60 L
,,,..+ ' ~
4
- c. ?l l'.
o T I f phf ' ~y-7 ,g .y . C) Co'ntinue to' maintain an indicated wide range L:)a :<. ~ - . . .
.. J ' = ' level in' the affected S/G AND maintain steam - =.,
9 , : pressure less than RCS pressure p<
- The operator should frequently monitor affected-S/G level =and pressure. If. level and/or pressure
~ . start to increase, either steam the S/G via the - SDBCS system or drain via'the. blowdown system.
1 D) .IF_ naturel circulation cooldown is being (, , _ performed, continue monitoring for reactor lg vessel head void formation as per Step 10.D 6: k... .c
.The operator should at this' point review '
p'~,._/ -
~
n- . indications of head void formation as delineated
. ;in Step 10.D.6. 'N- E)- IF necessary,--establish radiation control. areas
, -in -any affected reglons (i.e., S/U and B/D dis,
-turbine building sump areas): ~The operator =should inform Health Physics
- j. y
, personnel. They should' monitor these ~
g? '
~ .potentially adfected areas and install barriers ' ,.~
as necessary.-
~
s - 9
~
WP84989 SECTION VII - 9.0~ PAGE 61. f A,. I'
7--.
~ .
m 6 n-g,,qq STEP 13: When the RCS is' cooled to ~ 120'F and RCS pressure is
? ' L)~ .~ 50 psia,' drain the"affected S/G AND drain the RCS to the S/G tube maintenance level:
A) Drain t'he 'affected S/G using the blowdown system to the S/U and B/D.DI system: To drain "A" S/G, the operator must open 2CV-1015, 2CV-1016, 2SGS-27 and 2SGS-28.
-To drain "B" S/G, the operator must open 2CV-1065, 2CV-1066, 2SGS-29 and 2SGS-30. ' B) - When the affected S/G has been drained, collapse ~
the' pressurizer steam bubble AND drain the RCS cy w .to.the S/G tube maintenance levels as per
; 'u.f OP 2103.11:
Draining of the RCS below-:the S/G tube maintenance level will stop the tube leakage. b r
.\~/ -WP84989 SECTION VII - 9.0 PAGE 62 L
l
h 10.0 INADEQUATE CORE COOLING RECOVERY ACTIONS 10.1 Operational Goals The primary operational goal of the ICC tab is to maintain or replenish the RCS inventory in order to completely cover the i fuel with a liquid or two phase mixture. The core is considered adequately cooled as long as the liquid or two phase mixture i level is maintained above the top of the fuel. A related operational goal is to maintain a heat sink for core decay , heat removal. Loss of available heat sink will develop into a loss of RCS inventory out the RCS safety valves. If corrective l' actions are not taken, this situation could ultimately develop into an ICC condition. , 10.2 Description of Inadequate Core Cooling (ICC) ' In the majority of cases, multiple system failures must occur in order for situations to develop requiring entry into the ! ICC tab. f i Inadequate core cooling occurs when the core is not covered by a liquid or two phase mixture. The ultimate consequences ! of core uncovery is dependent upon the length of time that the l uncovery lasts and the depth that the core is uncovered. Two separate conditions exist for the ICC tab. One entry condition addresses the CETs indicating that a superheat condition exists for the indicated pressure of the RCS. The other entry condition is a complete loss of feed to the S/Gs. This condition, if not corrected, will degrade into an ICC situation. 1 4 WP84989 SECTION VII - 10.0 PAGE 1 i
y s:
'The entry condition based on the CETs indicating a superheated-J ) ' - condition is indicative'of core uncovery. When the rate of core boil off exceeds the rate of.the supply of cooling water, the upper portion of the core becomes uncovered. This will cause i superheated temperatures at the CETs and possibly the hot leg -RTDs (TH. eme gency c re c ng system (ECCS) is funcdonkg normally, the temperatures should return to saturation. For superheat conditions to exist for any appreciable time period, ,
failure of systems capable of removing decay heat has to be sustained. These system failures may range from overridden I components or system misalignments to actual equipment mal-functions. t e f g' Corrective actions for'CETs in Region 2 of Figure 2 stress
?()
reverification and restoration-of maximum cooling flow. This ' should include starting all available charging pumps, removing ', any potential override conditions, maximizing HPSI flows and, , t if possible, LPSI flows. As long as a S/G is available as a
~ -heat sink and RCS inventory can be maintained, sufficient I y
decay heat removal capacity should exist. Opening the ECCS l Svent isolation valves may-be required to depressurize the RCS. This will increase HPSI-flows,-introduce safety injection tanks, and possibly introduce LPSI flows. The ECCS vent path for ANO-2 is equivalent to 5.4 in or .0375 ft.2 . If the ECCS vent isolation valves do not-open, or if the capacity is not suf-
-ficient, opening all high point vent system valves and uniso- )
f}
%/
lating LTOP isolation valves will provide alternate flowpaths.
- WP84989 SECTION VII - 10.0 PAGE 2 4
7j -- -
, cc .The differences in CET temperature. indications and possible
> o 7-q.-
+
L/ clad temperatures are represented in Figure 2. Since CETs r are ' located ~a few. inches above the fuel alignment plate and allowing for possible delayed response times in seeing changes showing up on CET temperature indications, actual clad tem-
~
peratures should be higher than CET readings. If the CET
. temperature indications reach Region 3 of Figure 2, the peak - fuel cladding temperature- may have reached 1100*F. Above this temperatdre there is a potential for cladding rupture.
Also, the zircaloy-water reaction will begin to add a signi-ficant amount of heat to the fuel cladding, thereby greatly increasing the possibility of core structural damage unless - adequate core cooling is restored. b
- (,l:
Entry into the ICC tab due to a complete loss of feed addresses a potential ICC situation if corrective actions are not taken to restore feed. If some form of feed can not be restored, a loss of RCS inventory.through the pressurizer safeties will occur.
~
S/G inventory should last for - 20 minutes.- When they are lost i; as heat lsinkst-the RCS- fluid heats up and expands into the
. pressurizer. RCS pressure increases to the safety valve set-point causing.the loss of RCS inventory. Eventually, the loss of RCS inventory will create an ICC situation. If feed to the -m I(
v- J
~ -WP84989 ,
SECTION VII~- 10.0 PAGE 3 L ___. __ _ _______ _ _ __.-
-v: ._ , 4 J 7;q S/G(s) is restored, then adequate core cooling can be reestab--
^( )
4 lished,. but if primary feed and bleed must be used to ' cool the core, it should be initiated prior to pressurizer safety valve actuation. The longer ECCS. initiation is delayed, the deeper I and longer core uncovery may exist. I
' Direction is provided in a complete loss of feed situation to open ECCS vent isolation valves if S/G feed is not immediately ,
a recoverable and if the loss of. effective S/G heat sink is in-dicated by RCS (T ) > 560*F and increasing. l qws RCS (T ) > 560'F was selected since a value below this should
-be maintained if the S/G safeties are a source of steam removal '
f~} ' from the S/G(s). To allow for possible instrument inaccuracies .
- L,J :
t or conditions of high decay heat loads, the (and increasing ) l
^
s' was added to ensure positive ' indication of loss of S/G as a ,. heat sink. .' t Guidance is also.provided in this tab'for attempts to recover i feed to a S/G. Restoration of feed by. individual systems is listed in preferred sequence, but the goal of the operator t. should be to establish any method possible to feed a S/G prior to having to shift to a primary ' feed and bleed situation. 9 i O~
- \~ !
~WP84989' SECTION VII - 10.0 PAGE 4 Li
-g-EFW is the preferred method due to the fine control afforded
'p the operator as well as his familiarity with this system. If * =
neither EFW train can be restored, the operator should go to the next preferred method of supplying feedwater to the S/Gs. i
- Once some form of feedwater flow is established, the operator should attempt to restore an EFW train (preferably 2P-78) if l manpower and plant conditions allow. The EFW system provides the fine control required to maintain stable hot standby conditions.
I MFW would be the next preferred method since it may be quickly attained and operators are familiar with this method, although. not necessarily in this situation. Again, failures in this ' p) L_. system have occurred in order to be in a complete loss of feed , situation. Recovery of HFW may be established quickly and has .{ 9 the advantage of feeding the S/G(s) regardless of S/G pressure. l . Care should be taken when restoring initial feed rates to the , i S/G(s) due to the potential for feed ring collapse. A disadvantage would be that if MFW is established, maintaining MFW feeding for !
- a long period will be complicated by RCS cooldown and eventual loss of steam pressure to the MFW pump turbine. Eventual use of an EFW or a condensate pump will probably be required.
4 f. The last available method of feeding a S/G will be using condensate pumps. This will require depressurizing the S/G to a value below the high discharge trip.setpoint (753 psig i
'p . for 3 minutes) of a condensate pump.
WP84989 SECTION VII - 10.0 PAGE 5 g __m._____ - _. . _ _ . _ . . - . . . _ _. . . . . - _
e-Depressurizing the S/G may deplete the S/G water inventory to low levels. Care should be taken when restoring initial feeding to the-S/G(s) due to the potential for feed ring collapse and/or thermal shocking the S/G tubes. During the depressuri-zation, MSIS must be reset when required to prevent complete
' I isolation of the S/Gs. SIAS may also be reset if required to l prevent further complication of the casualty.
10.3 Safety Functions Affected Inadequate core cooling can only occur when failures of several I safety functions have occurred. The core heat removal safety function is ultimately concerned with transfer of decay heat i from the fuel to a heat sink. This can be accomplished as l
-w long as the core remains covered by a liquid or two phase mix-ture.
s The normal method of satisfying the RCS heat removal safety . I function is to transfer the core decay heat to the S/G(s). Some accident situations require transferring the core decay ! heat directly to the containment atmosphere. This situation l would require verification of the containment integrity safety function. Each method of heat removal requires the RCS in-ventory safety function be satisfied in order to maintain the Core Covered. WP84989 SECTIO!! VII - 10.0 PAGE 6 i
fi ,' , f-: in(-R; , l The complete loss of feed situation, if not corrected, vill
. -(j ' ~
first. result in a loss of RCS heat removal safety function and then develop into a loss of RCS inventory safety function. If control of these two safety functions is not regained, the * ,, , accident will lead'to a loss-of. core heat removal safety func-1. tion. Alternatives for decay heat removal after a complete 'l
. loss of feed consists of regaining _some method of feed, including S/G depressurization and using condensate pumps, or using a pri- ,
k mary feed and' bleed method. a
.a' l
The primary feed and bleed method consists of actuating SIAS and opening ECCS vent isolation valves. Once these valves are opened, the operator should monitor containment pressure and temperature '
. /) . to verify the containment ~ integrity safety function is maintained.
- % J To prevent core uncovery, and therefore ensure core heat removal, primary feed and bleed should be -initiated prior to the RCS 1
heating up~enough to lift the-RCS safeties. .. I I l s 9 4 i fg. U WP84989 SECTION VII 10.0 PAGE 7 i
( ) 10.4 !!ajor Parameter Response: The parameters and instrumentation discussed in this section t are selected to provide operator information necessary to determine the adequacy or potential inadequacy of core I cooling. Instruments selected for discussion are a small l fraction of the total parameter indications available to the i operator in the control room. At a minimum these instruments should be monitored for indications of ICC and to verify that corrective action functions have been accomplished. Instrument inaccuracies and potentially misleading indications can result in incorrect interpretations of the adequacy of core cooling. Inaccuracies and potential misleading readings are discussed for i some key instruments in relationship to ICC in the following ' es sections. l Core Exit Thermocouples (CETs) ' A) , The CETs are located at the top of each string of self , I powered neutron detectors. These CETs are located a few inches above the fuel alignment plate, which is above the f top of the fuel assemblies. They are located within tubes l which support and shield the instrument string from flow forces in the outlet plenum region. During accidents the CETs can function to temperatures of 1600*F or higher. The temperature of the fluid exiting from the top of the core can provide indication of whether the core is being i adequately cooled. As long as the core is covered by at WP84989 SECTION VII - 10.0 PAGE 8 ;
s least a two-phase mixture, the fluid temperature above the core will remain subcooled or at saturation temperature. If significant core uncovery occurs, the steam will become superheated as it passes the uncovered portion of the fuel i rods. The core exit temperature will continue to rise as more of the core is uncovered. If the two-phase or liquid i level starts to rise, the core exit fluid temperature will start to fall. This temperature will continue to fall until the level in the core is recovered, and the fluid temperature will return to a saturation value or possibly I a subcooled value. Allowances should be made for possible instrument ,'
) inaccuracies when reading CETs. With the RCS at saturation, ,
CET temperature indications should indicate near saturation temperature for the present RCS pressure. Instrument [, inaccuracies may allow indicated temperatures to read on , t either side of actual saturation temperature. If this situation occurs, relative readings and relative changes ! should be used to analyze core conditions. Due to physical l location, possible slow response times, core uncovery may be significant before superheat is indicated on the CETs. Comparisons should always be made with the temperature indicated by the hot leg RTDs if uncovery is suspected. I
~
WP84989 SECTION VII - 10.0 PAGE 9 i L
g7 B) RCS (T g ) Indications The hot leg temperature sensors are RTDs located within wells in the hot leg piping. It is conceivable that i during accident conditions with various flows through these nozzles, that the reading on some of the hot leg l RTDs could be influenced by these flows, which might include charging flow, flow out the surge line, etc. There are four (TH) safety grade channels per loop. These l l have a range of 525'F to 625"F and are environmentally - qualified for design base accident conditions. Other (Tg) instrumentation includes two control channels, one per ', loop, having a range of 100'F to 625'F which may be useful . as a backup indication. i The safety grade channels have a relatively narrow range , e compared to possible variations during severe accidents. If core uncovery occurs, the hot leg may have superheated i steam at temperatures above or below the safety grade l channels range. The hot leg RTD will not sense the lowering of the two-phase level until after the level falls below the top of.the core and superheated steam reaches the RTD locations. Some time delay in the sensor response to the occurrence of core uncovery and steam superheat can be expected as a result of the sensible pipe wall heat. i WP84989 SECTIO!! VII - 10.0 PAGE 10 t
C) RCS (T C
) Indi ations The cold leg temperature sensors are RTDs located within wells in the cold leg pipe downstream of the discharge of the RCPs. There are four (T C) safety grade channels per . loop. These have a range of 465*F to 615*F and are environmentally qualified for design base accident conditions. Other (T g) instrumentation includes four control channels, two readout on meters with a range of 525*F to 625*F, the other two readout on a trend recorder with a range of 0*F to 600*F. These instruments may be useful as backup instrumentation. In a loss of RCS inventory, the RCS temperature can decrease below the S/G secondary side temperature and reverse heat transfer could occur. The heat transferred to the primary side is absorbed by vaporizing the liquid flowing through the S/G U-tubes. As the RCS continues to depressurize, the heat load increases due to the increasing primary to secondary WP84989 SECTIO!! VII - 10.0 PAGE 11
temperature difference. At the same time, if RCS is [
. losing inventory,.then less liquid is entering the S/Gs.
When the heat transfer rate becomes greater than that ' i which can be absorbed by vaporization, the steam starts to ; become superheated. The fluid temperature entering the
, pump suction legs will then increase above the saturation temperature. The steam will lose some or all of the superheat as it passes through the suction leg loop seal.
As the steam flows through the RCP and into the discharge leg,. it will be cooled further by heat transfer with the ' metal components, and possibly by HPSI flows, if operating. Therefore, the fluid temperature in the RCP discharge leg may vary from saturation to superheat to fN subcooled.. Because of the superheating by the S/G, the
) t
' ~ cold leg fluid temperature may exceed the core exit fluid ' temperature. For this to occur the RCS pressure (and t saturation temperature) must be significantly below that of the secondary side. D) Pressurizer Level Response ic Pressurizer level is the most commonly used instrument for evaluating RCS inventory. In accident situations, abnormal plant conditions and possible environmental effects can render the use'of pressurizer level response impractical as a guide for RCS inventory control. For example, upon 7 WP84989 SECTION VII - 10.0 PAGE 12
e ey RCS depressurization, if reactor vessel head voiding occurs,
'~'
then a false high or increasing pressurizer level may occur, r Environmental effects such as reference leg heating can s result in false high readings of pressurizer level. . This
. could result in indicated pressurizer level stabilizing '
near the bottom of the indicating range, but actual level- i i
. could be lower. Thus, a constant, low level indication '
does not necessarily'mean that the actual level is stable near.the bottom of the indicating range. 10.5 Bases for ICC Recovery Actions I 'p
\ ./
i
'*', GO TO STATEMENT * .* If CET indications ~are in Region 2 of Figure 2, then they are indicating *
- in the superheat region based on the current system pressure and tem- *
~
- perature. . This condition is indicative of possible core uncovery. For *
~* this condition to exist for any appreciable time period, multiple system *
- failures, causing the loss of decay heat removal, have to be. sustained.' * .
- This GO. 70 statement directs you to steps for reverification of systems *' ,
- that should be operating to remove decay heat. Also, these steps will *
'* direct opening of ECCS vent isolation valves if adequate cooling cannot * *:be obtained. * -*******************************AA******************************************* ,
. ().i b
" WP84989 SECTION VII - 10.0 PAGE 13
***********************************************************************a**** )
GO TO STATEMENT
- S/G(s) will continue to function as heat sinks for - 20 minutes after a *
- complete loss of feed. In order to ensure adequate core cooling is ob- *
- tained using RCS feed and bleed method, the ECCS vent isolation valves *
- should be opened after the loss of S/G(s) as a heat sink and prior to *
- RCS heating up to RCS safety setpoints. This GO To statement directs *
- opening of ECCS vent isolations if S/Gs are lost as a heat sink and some *
- form of feeding cannot be immediately recovered. RCS parameters of T *
* > 560'F and increasing is used for positive indication of a loss of S/Gs *
- as a heat sink. RCS (T c) > 560*F was selected since a value below this *
- should be maintained if the S/G safeties are a source of steam removal *
- from the S/G(s). To allow for possible instrument inaccuracies or con- *
-s
- ditions of high decay heat loads the ( and increasing ) was added to *
- ensure positive indication of loss of S/G as a heat sink. This Go To *
- Statement is in effect anytime you are performing actions to restore *
- feed to a S/G.
- A***************************************************************************
STEP 1: Verify that no more than two RCPs are running (one in each loop): Forced flow is the preferred condition if 5/G feeding is reestablished. Verifying that no more than two RCPs are running minimizes the heat added by RCPs. Maintaining one RCP in each loop ensures that a forced flow condition exists even
^'
if feed can only be reestablished to one S/G. WP84989 SECTION VII - 10.0 PAGE 14
STEP 2: Attempt to maintain S/G level (s) 1 30% by wide range indication: In order to maintain an operable, functioning heat sink. in a U tube S/G approximately 1/3 of the U-tubes must remain covered. Wide range S/G level indication of
~ 23% corresponds to - 1/3 of the U-tubes being covered.
The goal of this step of maintaining 130% allows for possible instrument inaccuracies and provides a safety margin to maintain a functioning heat sink if recovery of feed is delayed. Recovering some form of feeding the S/G(s) is covered in the following substeps and are listed in order of preference. l Order of preference for restoring feed to a S/G is EFW first, followed by HFW, with attempting to establish condensate flow to a S/G being last. Even after a S/G boils dry, core heat removal can be accomplished if t-feed to a S/G can be re-established. In order to successfully remove decay heat by using a feed and bleed method, the opening of an ECCS vent path and establishing charging and HPSI flows requires initiation shortly after the effective loss of heat sink. WP84989 SECTIO!! VII - 10.0 PAGE 15 L
I 6 v j_ A) Verify that S/G blowdown is isolated:
$~
This should already be completed, but reverifying that S/G blowdown is isolated ensures that as much S/G inventory as possible is maintained. This will ensure an effective heat sink is maintained for as long as possible allowing more time-for operator restoration of feed.
... CAUTION . . -IF'ALL FEEDWATER FLOW TO.THE S/G(S) IS LOST AND LEVEL REMAINS BELOW 40% .
- NARROW RANGE FOR > '15 MINUTES, SUBSEQUENT _ FEEDING SHOULD BE < 150 GPM ' .
UNTIL AN. INCREASE IN LEVEL IS OBSERVED OR UNTIL CONTINUOUS FLOW HAS BEEN.
. MAINTAINED FOR 5 MINUTES. .
THIS' CAUTION IS CONCERNED'WITH POSSIBLE S/G FEED RING COLLAPSE.- .
~
- IF NARROW RANGE LEVEL INDICATION DECREASES BELOW 40%, APPROXIMATE FEED .-
. RING LEVEL, FOR > 15' MINUTES WITH NO FEED FLOW'THEN THE FEED RING MAY . ^ .-BECOME FULL OF STEAM INSTEAD OF LIQUID. RE-ESTABLISHING FEED AT FULL' .
FEED FLOWS COULD CAUSE~ SUFFICIENT WATER HAMMER TO COLLAPSE THE FEED .
. RING.
- d i
?^s . ,o ! ) ' WP84989 SECTION VII - 10.0 PAGE 16
-g. 3 ) J ~ . -s m J.: CAUTION (CONTINUED) .
- ( V
,
- BY' ATTEMPTING TO REESTABLISH FEED FLOW AT < 150 GPM, THIS ALLOWS TIME L
'* FOR VENTING AND/OR COLLAPSING POSSIBLE STEAM VOIDS, THUS MINIMIZING PO- . ..TENTIAL. WATER' HAMMER AFFECTS. ONCE A LEVEL INCREASE.IS OBSERVED OR FEED. ;. FLOW HAS BEEN. ESTABLISHED FOR 5 MINUTES, THEN ANY POSSIBLE STEAM VOIDS . SHOULD BE COLLAPSED. .
V B) Attempt to establish EFW feeding of the S/G(s).
^
- 1) Verify a suction flow path.
'2) Verify a discharge flow path.
- 3) Verify at least one EFW pump running.-
9-'s 4) Verify EFW pump discharge pressure is greater than S/G pressure. Establishment of any form of feeding S/G(s) is aof high priority throughout these steps. Since feeding the S/G with EFW is the preferred method,
.then it is reiterated to attempt to establish 1
EFW flow in this step. If expeditious establish-ment of. EFW is not possible, then continuing on and establishing any form of feeding is desired. 5
,/ h V, , L_WP84989, SECTION VII - 10.0 PAGE 17
~ s. p =M [',
- w. ,
s +t 4
,.< , If manpower and/or plant conditions allow, then V -(.! \
i.'
~~
s , 3 ' continued actions to restore EFW is still de-7; sired 'since this system allows for the fine - control. required to. maintain stable hot standby-conditions and allows controlled transition into plant cooldown: T
- a
- GO TO STATEMENT 2,1;; '
'A *1IF EFW is . reestablished, then direction to Step 5.0 of the Reactor Trip * ,
- Recovery tab is provided here. This will allow a continuing. check of
- ts*
,c, .. *l safety functio'ns'and direct plant operations to establish stable plant *
- ccnditions. *
, -. r -(pas ****************************************************************************
A C) ]f EFW' flow cannot -be' established, attempt to restore MFW flow - In order to reach this point'in_the procedure.
~
y -
. both EFW trains ,have failed and the MFW pump h' as.
1
~
failed to provide feed to the S/G(s). 'The-
- y
.4 i
_n_ >
' N) ,
WP84989- SECTION VII - 10.0 - PAGE 18-w
rv -- :c r i k 7 s establishment of some feed flow is of the highest i V
'+~^~ ' priority at this point. Two categories of HFW system failures and possible corrective actions - are addressed in the following steps. The first ~
deals with the MFW pump running but not supplying feed to the-S/G(s). The second is concerned
- with making available and starting a MFW pump.
y Also included in these steps are some concerns of maintaining MFW flow and eventual concerns with
.a cooldown in this situation.
, ~ e
- 1) IF_a MFW pump is running:
1/~~N N.J . a) _ Verify a discharge flow path is avail-able. b) ))(necessary,_throttleMFWpumprecirc
. -valves ini 2C02 to raise discharge pres-
- sure above"S/G pressure.
c)- (( necessary, take manual control of running MFW pump to increase discharge
,s pressure above S/G pressure. ~ * .- , These-steps address conditions where the ..
c , a _ MFW pumpfis'still running but feed has not been' maintained to the S/Gs. Since g.- . iWP84989 SECTION VII - 10.0 PAGE 19 l
? ,
__m,-,.,,w.. , _ - _ , , - . . . , ,_m - - , , - ~ _ . , . ..,.,.-_,,....,..,,...-.s.-..- .
iii a. protective MFW pump trips have not initi-
!%j i ~
ated, this implies that possible-component malfunctions that are easily correctable have occurred. The above steps verify system availability to deliver feed to the S/G(s) and provides guidelines on some possible failures.
- 2) IF a'HFW p' ump is NOT running:
The MFW pumps may not be running for i several reasons. The pumps may have been secured manually following.the trip'if EFW
- f w[ was running properly at the time. The. pump
\_).
may have automatically tripped due to exceeding a trip setpoint. The following
. steps provide guidance for restarting a HFW pump and verifying S/G feed flow.
a) Verify a suction flow path:
- Low suction pressure or low suction flow trips may occur from misalignments'or
- s. '
-failures in the suction paths to the Mnf pumps. A low suction pressure trip. ~
V;s a occurs at ~ 450 psig while the low suction - flow trip.could occur at < 4000 gpm. ()Y WP'84989 SECTION VII'-'10.0 PAGE'20'
.h _
m_, , . . . _ - g w 4
, J
" 4 4 _ %: s n, g=
.3 w , Q w: ~
} % 4 '3~~ jq 3
.I -Normally the low suction flow trip is ! %* ) -<~
bypassed via handswitches (MFW pump low suction flow bypass 2HS-736 for 2P1A, ,E .c, .
.and 2HS-743 for'2P1B). I; <n 4v '
I
~ ~ " . b)' ' Verify a discharge flow path is available:
s , . li e, . +
' 4. High discharge pressure trips could
- r
, occur if isolation occurs downstream- ^
as of 2EIA and 2ElB feedwater heaters
' 'll and the MFW pump recirc valve (s) do not actuate properly. -This trip occurs p
[: _ "if > 1300 psig is sensedidownstream of the l feedwater heatees 2E1A or-2ElB. p .:
' ' : i:
Verify a' condenser vacuum'of-< 7 psia.. .j
~
4 c)
.is:available - . ,,
o . -
- . 0
^i ~ - 2' fIf condenser vacuum-has degraded.to 7, . f . ~-14" Hga.(~.7.22 psia),-then.the:MFW _}'
b $ ., , ._
,e pump will trip.
4+ . . r m , t 5
. z' .. .
y. i
- n. , - - f
,-F
- E -
'f y*, '
, E. - c , x., -
. SECTION VII - 10.0 WP84989: - .., , PAGE-21. ~ - {'. -..m ^
, d' '
. + -
e y- 4 w . _
., , .. , , .... . . .or . /- . . -n 7 %-4,.._,,,,,,-,.... - - , -,,-..~.,...,<,--_..w-,.n-~..-,e.~--,,,,...-,-,--, .cy-,-.4r--,v-v<,,,w
J -- f3, N-' i /- l NOTE- l
,- -l After a low vacuum trip-on a MFW pump has occurred, resetting of the MFW l ~
- ) pump on 2C02'will allow running the MFW pump even in a degraded vacuum l
-[' condition. - l fl
- l l After: aivacuum trip has occurred, then resetting of the MFW pump removes l 1l that trip from the circuit until vacuum is regained sufficiently to resetl
. ~ lithe trip._ . _ This would allow the running of a HFW pump without vacuum if l ._l;the-operator resets the MFW pump. If vacuum recovers above the trip l l4setpoint, the vacuum trip will be reinstalled into the circuitry and a - l 7l subsequent loss of vacuum will trip the Mai pump. l f- ) -(1) IF a condenser vacuum is NOT L ( .,/ -
available and operation of a MFW pump is needed: 1 (a) , Verify at least one condensate
~ ~
pump is-running.
~
(b) Reset.and start.a MFW pump.
; -If the reason for the loss of the k .
MFW pump was due to a degraded vacuum condition,. consideration-
^
should be given to starting a MFW M
-WP84989' - SECTION VII --10.0 PAGE 22 t
.n
- y. -~> 1 k.
..,s -4 \.
m .
. pump regardless of ' vacuum condi- 1 H,,,,/ ^ 'tions. At this time, the highest priority is establishing some feed ' ' A + ?> 'to a S/G,. thus preventing opening -
of ECCS vent-isolation valves. The
.. above steps give the operator the a
option of starting a MFW pump, i regardless of vacuum conditions.
, LThis is provided since recovery '
of a MFW pump'should be a quicker-and more controllable method of
. feeding'S/G(s)-than attempting to feed with a condensate pump.
hs- E gy d) Verify.at least one condensate pump is 1 runnings- .. e (1)' -Verify discharge pressure of > -500 e
~
psig but <f750 psig. (2) 'IF necessary,. shut MFW pump.recire valves on.2C02.~ us ,- . . I - l(3) IF 'necessary, adjust condensate -
..~ ' pump recire valves on 2C02.. + _
l3_ ' -
. 6 , %. ~ , , ' ff~:[. ~
A_] a' y0784989 -SECTION VII 10.0 PAGE 23
.~ ~
m 7_",C .,
a Due to electrical control schemes, in
~
order to start a MFW pump, at least one condensate pump must be running. Also, the suction pressure to the MEN pump has to be > 450 psig or a trip will occur. Direction is provided to raise condensate pump discharge pressure to > 500 psig to ensure that the low suction pressure trip is not in effect. The condensate pump. will trip if its discharge pressure reaches 753 psig after a 3 minute time
-3 delay. Direction is provided to nain- \ j tain the condensate pump discharge pres-sure to < 750 psig to ensure the con-densate pump is maintained, e) Verify 2HS-0736 (MFW pump 2P1A low flow bypass) AND 2HS-0743 (MFW pump 2PlB low flow bypass) on 2C02 are in the bypass position:
Both low flow bypass switches are normally maintained in the bypass posi-L tion. This step verifies these hand-switches in the bypass position to ensure k
,WP84989 SECTION VII - 10.0 f PAGE 24 l
e
y; j?+. . j .
' ;;+ - '
w 6
.i ,x.- ~
that a potential trip. path-is not in
. i A' ,,,) ~: .^ _
force. A low suction flow of < 4000 gpm
, - +- <
will trip the MFW pump if the.handswitches
. _ , are not-in the bypass position.
1-
- x. .
.f). Verify that NO alarms exist associated with MFW pump lube oil systems. ; , _. (1) 2K03 F-5 (MFW pump turbine 2K2A bearing oil pressure low) +; OR .m - - -(2).. 2K03 F-10 (MFW pump turbine-2K2B s.
g bearing oil pressure low). Q. - O -. .. - , p .
"W ~
The, MFW pump will trip if bearing oil -
. pressure sensed at either the HFW pump or turbine is < 4 psig. By verifying. ~ , 'that no alarms-are in on the MFW pump lube oil system,'-the operator.can be- 'sa'tisfied that the lube oil system is 4 ' -operating prop'erly.
k
+- 'I g c-t,- -Q):^' : .+ > AP84989.- , - SECTION VII - 10.0 PAGE 25' 1 g I $ #
( .
.y . p, ~ ~
i
~ , $ >
g - z
~
- l-'
.. c , ' ;N,Q#i . . v. :-
3). . Attempt'to reset and start a HFW pump, AND -
-'E ='; '- ' - .if; unsuccessful, attempt-to reset and start s .
the other MFW pumps After' verifying MFW pump start criteria are
. . satisfied, attempt ~ to reset and start , - either purnp. If the. selected pump should I f;14: s 4 - .not start, there may be problems in that
- M;;
, W, . - pump's control circuitry. Attempt to reset-
^
and start the remaining pump.
, 4) .
IF MFW feeding of S/G(s) is established: ; s a.a - ef .a) Attempt to establish hot standby con-O y' ditions. b)- . Monitor and attempt to minimize cooldown. - c) IIF(necessary,'resettheMSISvariable-
.cs : trip setpoints.
- x. .. '
y
~ -I . d) Attempt to make EFW pump (2P7B)-avail- ' ' able . ' /i IF necessary to minimize possible ~
e)
'cooldown rates, W
restart all available RCys~ fg r-(1) Verify RCP.res' tart criteria p~er <
# N ,y,s #
- Appendix H are satisfied. ,
y%
- Q ... ..
, "WP849891 ~ SECTION VII I 10'.0 s
4 PAGE 26- i
- ;a. ,
?
y- - j i ( If a MFW pump is returned to service, the -
"r;- + . ~ .immediate concern of providing feedwater to Ac , the S/G(s)'has been-resolved. Running a 'MFW pump will affect the RCS cooldown by drawing steam from the S/Gs and by feeding the S/Gs with cold water. If possible, hot standby conditions should be established.
If necessary, the MSIS variable setpoint
$ should be reset to prevent isolation of the only available feed source. Efforts to regain an EFW pump (preferably 2P-7B) should continue. EFW'has better flow 1 4 control at low feed flow conditions which -gb~N; helps the operator better maintain hot > y/ ~
standby conditions and will afford finer temperature control during a cooldown. Until 2P-7B is regained, consideration
-should be given to restarting available RCPs, as necessary,'to allow pump heat to' help maintain' hot standby conditions.
OP-2103.06 requires RCS T' to be 2 500*F ave
,, before starting the 4th RCP due to core ~ lift considerations.
d yd _ [], ws .. WP84989- ; SECTION VII - 10.0 PAGE 27
+ , a
- r r .:..
t1
;~ . . , s J.- - - 5) IF decay heat levels are inadequate to main-s 1 ' ^~~
tain MFW pump operation: a) Operate the MFW pump as long as it is available. b) IF EFW pump (2P7B) is unavailable AND RMFW pump operation is no longer feasible, shift to feeding S/Gs with condensate pumps. Due to the cooldown' associated with MEW
-pump operation, the steam supply available 'l , to run the pump will be limited.. depending ~
f. on. core power history. . Operating a MFW pump a's long as the decay heat can support it- _ -allows time for EFW restoration attempts. If EFW (2P-7B) remains unavailable, loss-of the MFW driving steam will require feeding'
.the S/G(s)fwith condensate pumps. Since- 'the S/d pressures will be. low when the MFW- ~
pump becomes unavailable, transferring to condensate pump feeding should pose no
.~
major problems. W. ..
. u 9
e
.y -
I .
. SECTION VII -'10.0 IWP84989 PAGE 28 ~
N
-ET D) IF EFW OR MFW flow cannot be established, attempt
- to establish condensate flow to the S/G(s).
This step and the following steps address the i use of the condensate pumps for S/G feed in the event'both MFW and EFW pumps are unavailable. l In order to use the condensate pumps to feed the S/G(s), secon'dary pressure must be reduced below
' the condensate pump trip value (753 psig/3 min).
I Due,to the time taken to reach this point, and~ the amount of inventory loss required to depres:.urize below the condensate pump trip ' e/~s, value, S/G levels may be' extremely low. In' . i..) ^ .l establishing condensate feed,:the operator - should be aware of -the MSIS variable setpoint, . and.take care:to minimize the initial feed rate.
. I ~
- 1) Verify at leastione-condensate pump running. 1
- 2) Take manual. control of valve controllers on' j 2C02 AND close both HFW regulating valves.
3)- Take manual control of valve controllers on s l2C02 AND.close both MFW regulating bypass-
, . valves. ' ~ - 4); Take' manual control of valve controllers-n AND close both MFW pump recirc valves on'. i ~. (",1 ,- , ~2C02.
WP84989 SECTION VII : 10.0 PAGE 29 ; L
- w v
- The set of steps above begin to set up positive .7_
i )~
'~'
control of the feedwater system prior to attempts to feed the S/Gs with condensate pumps. Taking manual control and shutting MFW regulating valves I and MFW regulating bypass valves ensures the valves
' l are closed and minimizes potential ~ overfeeding i situations. Both of the bypass valves.should be approximately 15% open and MFW regulating valves . should be closed, if proper Reacter Trip Override , Actuation has occurred. The MFW pump recirc l'
valves should be shut to assist in raising condensate pump pressure. 61
.5 '/5 -.l- NOTE l.
(-)I l IF alarm on 2K03'A'-2 (2P2A/2P2C condensate pump discharge pressure high,fl 'l-l 753;psig) OR alarm'on 2K03 A-13 (2P2B/2P2D condensate pump discharge l llf pressure high,- 753 psig) is alarmed' for approximately 3 minutes, then a l . I'
'l condensite pump trip will occur. l .g
- 5) Throttle both condensate pump'recirc valves l to raise condensate pump-discharge pressure as high as possible.
l k;; I
;~~. -- <a . .
WP84989- SECTION VII - 10.0 PAGE 30
.i 4 4W ' + ,s 1
s Condensate pump discharge pressure should be l raised as high aus possible in order to es-tablish feed to S/G(s) as soon as possible. In order to establish condensate feed to i; S/G(s), the S/G water inventory may have l been depleted to very low levels. Due to the i possible low S/G(s) water inventory, any delay in establishing condensate feed may require the ECCS vent isolation valves to be opened in order to maintain adequate core l' cooling. The note and step above place emphasis on the high discharge pressure condensate pump trip. An inadvertent trip- ' w of a condensate pump could cauce unnecessary x) confusion and may delay S/G feeding for a l considerable length of time. ,' i 4 i ma- - WP84989 SECTION VII - 10.0 PAGE 31 i
)
CAUTION .
. ENSURE THAT MSIS VARIABLE TRIP SETPOINTS ARE RESET WHILE DEPRESSURIZING . . S/G(S). . i I- . THE RAPID DEPRESSURIZATION OF THE S/G WILL REQUIRE RESETTING OF THE . j . MSIS VARIABLE TRIP SETPOINT TO PREVENT ACTUATION IN ORDER TO ESTABLISH . . CONDENSATE FLOW. THIS IS EMPHASIZED AS A CAUTION SI!!CE AN MSIS . . ACTUATION WILL ISOLATE THE'S/GS AND SECURE THE CONDENSATE PUMPS. .
- RESTORATION OF A FEED PATH AND RESTARTING CONDENSATE PUMPS WILL REQUIRE .
l
. RESETTING THE MSIS SIGNAL. SINCE THE S/G WATER INVENTORY MAY BE VERY . . LOW, ANY DELAY IN ESTABLISHING CONDENSATE FEED SHOULD BE PREVENTED. . .-...................................... i r.
s a CAUTION . I r
. MONITOR RCS PRESSURE AND RESET SIAS VARIABLE TRIP SETPOINTS IF NECES- .
l'
. SARY. .
(
. THE RAPID DEPRESSURIZATION OF THE S/G(S) WILL CAUSE A COOLDOWN OF THE . . RCS. THIS COOLDOWN MAY REQUIRE RESETTING OF THE SIAS VARIABLE TRIP
- l
. SETPOINT. RESETTING OF THE SIAS UNDER THESE CIRCUMSTANCES IS TO PREVENT. . ANY POTENTIAL CONFUSION THAT MAY OCCUR SO THAT NO TIME OR EFFORT IS . . LOST IN ATTEMPTING TO ESTABLISH CONDENSATE FEED.
- I' 7
l x ./
' WP84989 SECTION VII - 10.0 PAGE 32 i
1y ,,
.s . .
L 3. c
. '/ ~2
- 7) .,*-
, [4,3 E6 ). IF the main condenser is available, use
/
M} '_, m SDBCS turbine. bypass valves to depressurize w
.S/G(s) below condensate pump discharge pres- ,n sure: i Y . w ,
I j' SDBCS turbine bypass valves are the pre- [ '_ ferred method of depressurization to ensure that condensate inventory is conserved.
, p , wt i-h #s .u
- 7) E the condenser is NOT avail'ble, a use
~
1
.SDBCS atmospheric dump valves to depres- ~- '
s'urize S/G(s) below condensate pump dis-
.c ' charge pressure: -
3
., ' '_ , 4V -
t , ); , j[ ' .
? iIf SDBCS turbine bypass valves are unavail- - l- ~ .-able or. if capacity is- not stifficient to - , ? , 'providefadequate depressurization, the SDBCS- ' . i -, : atmospheric. dump valves should be used.- .) . q r % E' l' t :: ^
3,
' t v :- a A"b.
n'
, cu ; m . >
- 4. f
;.y '
e? q g
- N:, ,' . _ ,
W , . . #
.p -. , 4 y84989- SECTION VII.- 10.0' 'PAGE 33-
- q. -
x c
~ 'j',, ; s :
s
e _
3:
. , . e . e . . /. e e.. . . e . .-e~. ...................... 'd . .
CAUTION
- WHEN ESTABLISHING CONDENSATE FEED TO THE S/G(S), MINIMIZE CONDENSATE .
. FLOW l RATE TO THE S/G(S) FOR S MINUTES OR UNTIL A S/G LEVEL RISE IS IN- . i . ' DICATED .~ .
- I i
ESTABLISHING CONDENSATE FEED SHOULD BE THE HIGHEST PRIORITY AT THIS .
* . STAGE. MINIMIZING INITIAL CONDENSATE FEED RATES SHOULD BE OF CONCERN .
DUE TO POSSIBLE FEED. RING COLLAPSE. SINCE THERE IS NO DIRECT' METHOD . AVAILABLE TO MONITOR LOW FLOW RATES WHEN ESTABLISHING CONDENSATE FEED, .
- . 1 SUBJECTIVE METHODS SUCH AS MFW REGULATING BYPASS VALVE POSITION WILL .
HAVE.TO BE USED TO ESTIMATE FEED RATES. .
, () - 1 - \_,/ ' .8)' Throttle MFW regulating bypass valves to l-establish flow to S/G(s): 'I t
h
'f I
a l' b v.
;WP84989; SECTION VII - 10.0 PAGE 34 l i 4
t x
- ;. 9) Monitor hotwell levels and makeup from the -/ 't CST as necessary:
s If SDBCS atmospheric dumps are being used, hotwell makeup will be required periodi-
. cally. ****************************n***********************************************
GO TO STATEMENT *
- IF condensate flow to the S/G(s) can be established, go to " Step 7.0 of *
- the Reactor Trip Recovery" tab. *
- This directs.the operator to the reactor trip recovery tab for reveri- *
- fication of safety functions. This will also give directions to place *
. , s;
- the plant in a MODE as directed by plant management.
- V *************************x**************************************************
~
GO TO STATEMENT *
-* If unable to: establish some form of feed to S/G(s), direction is- *
- provided to steps that will open ECCS vent isolation valves and *
- maximize feed and bleed cooling. *
-V, WP84989 SECTION VII - 10.0 PAGE 35 i
v. Y -? >
- +
S , A T
/ ,Ac . ~ STEP'3.0 IF the CET temperature indications are in Region 2 ' Ys., .-
of Figure 2:
,.Ar, . J - 4 CET indications in Region 2 of Figure 2 is indicative i of superheated conditions. This implies that the core , has become uncovered. For superheated conditions to l, - exist for any appreciable time period, failure of systems capable of removing decay heat has to be . , sustained. The corrective actions associated with this step consist of maximizing potential cooling -
l methods and~ attempting to recover RCS inventory. ( A) Maximize all availabe cooling methods:
'?($l N~/ / ' Verify'all available charging pumps are -g . 1) ' running:
t
-t V;SJ Charging pumps may have been placed in " pull to lock" due :to procedural Lcom : ~! .pliances,Letc. CETs. indicating superheat: -
a n
. '6~ imply core uncovery,'and starting all available charging pumps allows replacing RCS inventory even=though'highe'r than 4
{Ei , . normal'RCS pressure may exist. sr
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': WP84989L ~ .SECTION VII - 10.0. PAGE,36
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;_; .2) . Verify two HPSI pumps are running AND ~
attempt to maximize flow Since HPSI pumps may have been placed in i
-" pull to lock" or discharge valves over-ridden and throttled shut, directions are i provided for restoring them to actuated conditions. Also, if a HPSI pump has , -failed, it can be replaced by the swing HPSI puap (2P89C). These actions will I
possibly restore RCS inventory as long as RCS pressure is < 1450 psia. This step also ensures HPSI pumps are running and ' aligned to their actuated positions in the' (-)3
'~'~
event opening ECCS vents becomes necessary, l i:
, . 3) . Verify available LPSI pumps are running ..
i AND attempt to maximize flow: If RCS pressure is < 180 psia, efforts to l restart all available LPSI pumps will help: restore RCS inventory. If RCS pressure is-
> 180 psia, LPSI pumps should still be made - available since opening of ECCS vent iso- -lation valves may become-necessary.
I
<^s 1 ,'\ . .WP84989 SECTION'VII - 10.0 PAGE 37 i_a
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3 4)- ' Verify available S/G(s) are > 30% indicated wide range level:
~
As long as S/G(s) level (s) are > 23% wide I' range, the S/Gs should serve as an
. effective h' eat sink. l The 30% level.is maintained to allow for possible' instrument inaccuracies and to allow for a safety margin to ensure an avail-I able heat sink is maintained.
4
~
- 5) IF necessary,. attempt to establish S/G
. /~ Y- levels as per Step 2 of this tab:
l\_) . t Adequate cooling can be established if l
. sufficient inventory 'is available to cover:
I the core-and if a S/G is available as a heat sink. RIf the core has-been^ covered by the 1 previous steps, maintaining adequate core -[ coolingican be maintained if a S/G heat sink is'available. 1 e 4 k-
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s_ WP84989 SECTION VII - 10.0 PAGE 38 F 1 t N x
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GO TO STATEMENT *
,IF CETs have been restored to Region 1 of Figure 2, go to'"SIAS" tab. * *-
- i
'If corrective actions have returned CET temperature indications to the '* I subcooled region,'then the core level should be recovered. As long as-
- i
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corrective actions can maintain-these conditions, returning to the'SIAS
- tab allows verification of safety functions and establishing stable plant *
*.' conditions ' .
- 1 STEP 4.0~ IF opening of ECCS vent isolation valves is required s
f 'xi i This step is reached if. indications of core uncovery s,/ ' exist,- CETs indicating in Region 2 of Figure 2, ] L .,- or if a complete loss of feed has occurred resulting , in a loss of heat sink, RCS-(T ) > 560 F and increas-ing. Opening the ECCS vent isolation valves,.in conjunction with charging pump (s), HPSI pump (s), and !
.possibly.LPSI pump (s) flow establishes RCS feed and ]
bleed cooling. If the ECCS vent path cannot be~ -- established, opening LTOP isolation valves and opening the reactor vessel and high point vent valves can
' ~
provide alternate f1ow paths.
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ar r WP84989. SECTION VII - 10.0 PAGE 39 i J
ea
., - A). , Verify all RCPs are secured: \
n JI If.the RCPs are not already secured, the operator should secure them prior to opening ECCS vent isolation valves. Opening the ECCS vent path will rapidly depressurize the RCS and make continued operation of RCPs undesirable. B) Manually. initiate SIAS AND ensure that jto components are in an override position. Actuation of SIAS ensures that makeup sources
-are immediately available when RCS pressure 7/~Nr allows actuation. Ma'intaining the core covered 19). ' .is necessary to ensure adequate core cooling ,
so any possible additions to in RCS inventory.is ; desirable. Some SIAS actuated components (i.e. , ' charging pumps, HPSI pumps, HPSI . pump discharge valves) may be_-in an override position.
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They. should be restored to normal actuated posi-tions to ensure maximum feed and bleed.
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- WP84989c SECTION VII - 10.0 PAGE 40
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,. . C) Open ECCS. vent isolation valves on 2C09
< -, 1
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(2CV-4740-2 AND 2CV-4698-1):
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Opening the ECCS vent path provides a 5.4 in2 or 'i
.0375 ft2 opening directly to the quench tank.
L' If this path is opened, the quench tank rupture 1 disc will probably release to the containment building. i s . D) IF both ECCS vent isolation valves do NOT opens u I
- 1) Open LTOP isolation valves (2CV-4730-1,
.g 2CV-4731-2, 2CV-4741-2, 2CV-4740-2) on * ? 2C09
' As/_y , AND 'l-
- 2) Open reactor vessel AND pressurizer high f 1
point vent valves (2SV-4668-1, 2SV-4668-2, ,
~
L- t 2SV-4636-1, 2SV-4636-2,-2SV-4669-1) on 2C336-1 and 2C336-2. l These staps list possible alternate flow paths for establishing RCS feed and bleed. These paths will provide some restrictions if they are used for RCS feed and bleed. The LTOP reliefs' lift at 430 psig,- thus. , 1-supplying a back pressure on the' system and )
;-) .s_I . WP84989 SECTION VII - 10.0 PAGE 41 -,.g I' '. - . ___.__..____________.---_.m.
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1 g,y only allowing effective use of the charging pumps and.HPSI pumps for makeup. If the reactor vessel and pressurizer vent paths are used, they have a 7/32 inch orifice I which will restrict flows to less than a charging pump capacity for each flow path, i
- IF'ECCS vent' isolation valves were opened, go to "SIAS" tab.
- This directs _ the operator to the SIAS tab where verification of safety
- t
- functions can be performed and eventually stable plant conditions can be
- ok established. *
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-WP84989 SECTION VII - 10.0 PAGE 42 i
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