ML20154D650
| ML20154D650 | |
| Person / Time | |
|---|---|
| Issue date: | 06/28/1995 |
| From: | Lyon W NRC (Affiliation Not Assigned) |
| To: | Rosalyn Jones NRC (Affiliation Not Assigned) |
| References | |
| TAC-M54946, NUDOCS 9810070284 | |
| Download: ML20154D650 (22) | |
Text
9
, AA CEGO i p & UNITED STATES g j NUCLEAR REGULATORY COMMISSION o C WASHINGTON, D.C. 2055M)001
- June 28, 1995 MEMORANDUM T0: Robert C. Jones, Chief Reactor Systems Branch Division of Systems Safety and Analysis FROM: Warren C. Lyon, Sr. Reactor Systems <-
PWR Reactor Systems Section Reactor Systems Branch .
Division of Systems Safety and Analy is
SUBJECT:
RESOLUTION OF ISSUES IDENTIFIED IN THE 1983 SAFETY EVALUATION OF THE B&W ABNORMAL TRANSIENT OPERATING GUIDELINES (AT0G), (TAC NO. M54946)
REFERENCE:
- 1. Eisenhut, Darrell G., " Safety Evaluation of ' Abnormal Transient Operating Guidelines', (Generic Letter 83-31)," Letter from Director, NRC Division of Licensing to all operating reactor licensees, applicants for an operating license and holders of construction permits for Babcock & Wilcox pressurized water reactors, September 19, 1983.
The Reference Generic Letter (GL) addressed each AT0G step with respect to findings and issues, an' approach that led to similar or identical issues in i various parts of the reference review. Consequently, we consolidated the i issues as follows to facilitate review of the B&W emergency procedures i guidelines:
(1) entry into EPGs (E0Ps)
(2) reactor coolant system (RCS) inventory measurement (3) reactor coolant pump (RCP) operation (4) loss of AC power (5) containment (6) anticipated transient without scram (ATWS)
(7) pressurized thermal shock (PTS)
(8) cooldown and interfacing with other procedures (9) high pressure injection (HPI) cooling (10) SG control (11) degraded core l (12) RCS inventory / pressure '
(13) analyses (14) miscellaneous
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Further review identified additional issues:
(15). non-hot /non-pressurized NSSS conditions
-(16) containment (17) LOCA outside. containment !
.(18) severe-accidents
- ' (19) ' loss of AC power The disposition /binning of each of the AT0G issues is shown in the attachment.
Attachment:
As noted cc: PDR E. Weiss i
T-r
. 1 l
l i
l Table A1. Issues Identified in GL 83-31 i
s Table Column Item GL 83-31 GL 83-31 section where the issue or finding appears.
ID Item identification number or letter (s) used for cross-reference within Table A1. Numbers are those used in EG&G-Idaho evaluations (Ref.1). Lower case letters refer to items that EG&G did not identify.
Description Description of issue or finding.
Disposition Placement in one of the bins defined on the previous page is indicated by a B followed by the bin number (B1 - B19).
Duplicate and similar items are consolidated by closing selected issues and covering the material in another issue.
1 In each case, the issue that remains active is identified by
, using numbers or lower case letters from the ID column.
In some cases, GL 83-31 required that additional information be provided or that certain analyses or tests be performed.
Such issues are closed on the basis that the information was obtained if no further requirements applied. Each of these J 4
dispositions is identified in this column.
In some cases, disposition is identified by the forthcoming SER.
I GL 83-31 ID Description Disposition Section l 1.1 a E0Ps cover operator acticns for any Closed. Covered by i condition that potentially jeopardizes 48(seeIDcolumn).
fuel cladding, RCS pressure boundary, I or containment. l 1.1 b E0Ps bring plant to where non-emergency Bl. See also 48. I procedures apply, to cold shutdown or ;
to controlled stable condition which
. minimizes releases and which operators
- can maintain until suppcrt personnel plan future operation.
, If while in above a condition occurs that potentially jeopardizes fuel cladding, RCS pressure boundary, or containment, then E0Ps are used to cope 4
with condition.
1.1 c EPGs provide technical basis for E0P Broad requirement preparation and describe major operator addressed by TBD.
actions. Closed by GL 83-31.
4 I
GL 83-31 ID Description Disposition Section 1.3 d AT0G is responsive to requirements but AT0G obsolete.
is not fully developed, does not cover Adequacy of TBD to be all events and needs. assessed throughout SER.
1.3 1 Provide interim anticipated transient Closed. See B6.
without scram (ATWS) coverage before implementation.
1.3 la Provide interim NC coverage before Closed by Ref. 2. i implementation. i 1.3 2 Implement in accordance with NUREG-0737 Implemented. Closed.
(Ref. 3).
I 1.3 3 Upgrade in longer term to provide more B1, To be addressed comprehensive coverage of emergency in SER Section 2.2.
conditions.
3.1 e AT0G approach is sound and AT0G No action required.
provides acceptable approach.
3.2 f Entry and initial actions are No action required. !
acceptable for development and implementation.
3.2 4 Broaden entry criteria. B1 3.2 4a Provide interface information for other Bl. See also 38, 40, plant procedures. 40a, related analyses in 59 - 73 and 87.
3.2 4b Include inventory and vessel level B2 i nstrun.or,tation.
3.3 g Initial verifications are sufficient No action required. ;
for implementation. )
3.3 5 RCP trip criteria are to be based on GL Criteria accepted 1 83-10e response. following GL 83-10e !
review. Closed. :
3.3 6 Address LOOP. Include perturbations B4 which require operator attention, which may mislead operator.
3.3 7a Address loss of AC power including 6, 54, 69, 72 l elimination of unnecessary loads, actions to control RCS inventory; perturbations when power restored.
3.3 7b Include RCP restart phenomena in loss Closed. Contaii.ed in ,
of AC power. lla, 11b I 3.3 8 Consider radiatica and associated B5. See also 45.
isolation actions involving containment.
3.3 9 Provide additional ATWS guidance prior Closed. See B6.
to implementation.
1 l
l GL 83-31 ID Description Disposition Section 3.3 9a Address ATWS concerns identified in Closed. See B6.
Commission rulemaking, by generic requirements resulting from Salem event.
3.4 h Section IIIA, Loss of SCM, is No action required, acceptable for development and implementation.
3.4 10 PTS. Address RCS conditions outside Closed. Contained in l the desired region. 95. l 3.4 10a Address revisions due to USI A-49. Closed. Contained in ,
item ad. Related to :
- 95. !
3.4 11a Address RCP restart with steam in upper B3 head, mixing with subcooled water and resulting transient. Include RCP restart condition specification, pressurizer inventory needs to avoid l SCM loss, thermal / hydraulic behavior in '
upper head, induced head stress.
3.4 11b Consider upper head void and its B3, B13 treatment, including while remainder of RCS never loses SCM.
3.4 12 Consider loss of SCM during cooldown Closed. Section (GL 83-31 Section 3.9) . 3.3.2, above, provides followup.
3.5 i Section IIIB, Lack of Heat Transfer, is No action required. l acceptable for development and implementation.
3.5 13 Cover restrictions for HPI initiation, B9, 34 differences for number of HPI trains.
3.5 14 Cover PORV availability and high point B9 vents with HPI cooling.
3.5 15 Cover elimination of steam from the RCS Bil before extreme ICC conditions.
?.5 16 Demonstrate usefulness of RCP bump. B3 1.5 16a Items pertinent to RCP operation (3.2) 3.2 is a typo and apply to lack of heat transfer (3.5) should be 3.4.
and should be considered. Closed, lla applies.
3.5 16b Items pertinent to voiding (GL 83-31 Closed. 11b applies.
Section 3.4) apply to lack of heat transfer (3.5) and should be considered.
~.
GL 83-31 ID Description Disposition Section 3.5 16c Items pertinent to cooldown (GL 83-31 Closed. No ATOG Section 3.9.6) apply to lack of heat items remain, transfer (3.5) and should be (additional TBD items considered. identified in the SER) 3.6 j Actions to terminate overcooling No action required, transients (excessive heat transfer) are acceptable for development and implementation.
3.6 17a Items pertinent to RCP operation (3.3) Only remaining item are applicable to overcooling (3.6) and is RCP restart with should be addressed. overcooling. Covered by lla.
3.6 m Items pertinent to voiding (3.4) are Closed. No applicable to overcooling (3.6) and additional AT0G items should be addressed. remain.
3.6 n Items pertinent to cooldown (3.9.6) are Closed. No applicable to overcooling (3.6) and additional AT0G items ,
should be addressed. remain. :
3.6 17 Address overfill that results in water B10. See also 25.
in the steam lines due to excessive heat transfer conditions. Include <
those items discussed in SGTR (3.7) as I applicable to overcooling (3.6). !
3.6 18 Address blowdown of both SGs. B10. I 3.6 19 Review AT0G for applicability with an B10 l inactive SG and increased likelihood of I RCS voiding in that SG's tubes during )
NC.
3.7 o AT0G treatment of SGTR is acceptable No action required.
for implementation. j 3.7 20 Conduct analysis and improve guidance B10 for termination of RCS to SG leak prior )
to reaching cold shutdown conditions.
3.7 21 Conduct analysis and provide guidance B10 for alternates to steaming the faulted SG for purposes of heat removal and for SG level control.
3.7 22 Cover multiple ruptures in one SG. B10 3.7 23 Cover single and multiple ruptures in B10 both SGs.
3.7 24 Analyze and provide alternate methods 812 for control of RCS pressure, including inoperative PORVs and no pressurizer
. spray.
I
GL 83-31 ID Description Disposition Section 3.7 25 Analyze and provide guidance for B10 overfill of SGs and water in the steam lines during SGTR.
3.7 26 Include items pertinent to RCP B10. 11a applies operation (3.3) in treatment of SGTR except for SGTR.
(3.7).
3.7 26a Include items pertinent to voiding B10. 11b applies (3.4) in treatment of SGTR (3.7). except for SGTR.
3.7 26b Include items pertinent to cooldown B10.
(3.9.6) in treatment of SGTR (3.7).
3.8 p ICC guidance is acceptable for No Action required.
implementation.
3.8 27 Use RV level / inventory instruments. 82 3.8 28 Provide analyses as discussed in 3.13 59 - 73 when the topics are applicable to ICC.
3.8 29 Provide post-core damage guidance for 96. See also 39.
ICC conditions, including minimization of releases for SGTR and use of steam release for control of the plant.
3.8 30 Comments regarding RCP operation (3.2) Section 3.2 should be are applicable in providing ICC 3.4. Closed on the guidance. basis that RCP analyses are unnecessary for ICC operation.
3.8 30a Comments regarding voiding (3.4) are Closed. No applicable in providing ICC guidance. additional items remain that are not addressed in other items.
3.8 30b Comments regarding cooldown (3.9.6) are 39 applicable in providing ICC guidance.
3.9.1 q The post large LOCA cooldown approach No action required.
is acceptable.
3.9.1 31 Additional treatment of containment is Closed. Covered by needed for large LOCA as discussed in 41 - 45a.
3.10.
3.9.1 31a Other longer term containment needs for Closed. Covered by large LOCA are identified in 3.9.6. 38 and 39.
3.9.2 r The normal cooldown approach is No action required.
acceptable.
3.9.3 s The cooldown with RCS saturated No action required.
approach is acceptable.
GL 83-31 ID Description Disposition Section 3.9.4 t The cooldown with HPI cooling approach No action required.
is acceptable for development and implementation.
3.9.4 32 SG and RCS temperature distribution, Closed. Analyses flow effects and tube stress should be completed (59 - 73).
investigated for HPI cooling with dry Items 34b, 34c, 40, SGs. 40a, and 40b apply.
3.9.4 33 As discussed in 3.4, PTS may require Closed. Covered by changes with respect to 95.
pressure / temperature control while in HPI cooling.
3.9.4 34 Address critical restrictions 89 associated with manual initiation of HPI cooling, particularly when HPI is degraded or a PORV is inoperative.
3.9.4 34a Address potential conditions where HPI Closed as a special cooling is ineffective. case of 34; to be ,
covered there. l 3.9.4 34b Investigate system behavior to support Closed. Covered in item 32 of 3.9.4. 32.
3.9.4 34c Determine behavior with availability of Closed. Covered in I two, one, or no HPI pumps. expanded 34.
l 3.9.4 34d Determine if different operator Closed. Covered in I guidance is needed for two, one, or no expanded 34.
HPI pumps.
3.9.4 35 Clarify operation of the DHR system for Closed. Covered in I saturated RCS conditions. If such 89.
operation is intended then address voiding due to potential inadequate pump suction head. If such operation is not intended, then clarify wording.
3.9.5 u Subcooled cooldown procedures are No action required.
acceptable /or development and implementation.
3.9.5 36 Show that the pressure control method B12 is feasible and does not result in prohibitively large pressure swings.
3.9.6 37 Prior to implementation, cover RCS Closed since items voiding phenamena which could lead to were covered prior to interruption of NC during small break implementation and 74 LOCAs. Describe the phenomena, covers same material.
potential conditions where interruption of NC and/or heat transfer may occur, indications the operator can expect if it happens, and the likelihood of occurrence. Provide operator guidance.
GL 83-31 ID Description Disposition Section 3.9.6 38 Review cooldown procedures and Closed. AT0G-supplement as necessary. Consider specific and AT0G is entry. paths and potential cross-no longer used. See i transfers. For example, CP-105 is also 4a. '
referenced under conditions when the RCS may not be solid. During a LOCA, one can get into a closed loop involving CP-102, CP-103, and CP-105 in which cooldown is not permitted.
3.9.6 39 Cover degraded core during cooldown. B11. Also related to 29.
3.9.6 40 Consider items pertinent to RCP The correct section operation (3.2) during cooldown. . is 3.4, not 3.2. B3 and lla apply.
3.9.6 40a Consider items pertinent to NC (3.4) 88. See also 74.
during cooldown.' ,
3.9.6 40b Consider: items pertinent to RCS voiding B8. See also 11b and (3.4) during cooldown. 12.
3.10 41 Address instructions to reduce B5 containment hydrogen concentration and/or preserve containment integrity by venting. ,
3.10 42 Address reactivation of the containment B5 spray system with respect to influence on hydrogen flammability and flame propagation.
3.10 43 Justify selection of hydrogan B5 ;
concentrations for control actions with
- respect to instrumentation accuracy, uniformity of mixing, and accuracy with ,
which limits that affect behavior are i known. i 3.10 44 Include or reference instructions for B5 hydrogen recombiners.
3.10 45 Consider guidelines for operator action B5 l to manually initiate containment i isolation during an accident.
3.10 45a Consider guidelines for operator action B5 to preserve containment cooling capability in light of the potential for inadvertent isolation or to reinstate cooling following automatic or operator-initiated action.
GL 83-31 ID Description Disposition Section 3.10 46 Consider guidelines for operator action B3 to preserve RCr, cooling capability in light of the potential for inadvertent isolation or IG reinstate cooling following automatic or operator-initiated action.
3.11 v Initiating events such as natural No action required.
phenomena are adequately treated.
3.11 47 Extend AT0G to cover conditions other 4 than reactor trip and power operation.
3.11 48 Cover any NSSS condition that 81 jeopardizes or potentially jeopardizes an identified barrier to release of radioactive material.
3.11 48a Coverage can be provided in non- E0P Guidance for which no procedures when appropriate if action is required.
interfacing information is in E0P. Applicable to 4 and 12.
3.12 49 Consider multiple SG tube ruptures. B10 3.12 50 Provide instructions for alternate B10 (See, for feedwater sources (3.5 - Loss of heat example, Item 6 in transfer and 3.9 - cooldown). Section 3.4.10.1, above) 3.12 51 Provide guidance for failure of high B11. Related to 55 pressure RCS makeup systems as part of and 70.
efforts dis assed 7 in 3.8.
3.12 51a Provide guidance for failure of high 70.
pressure RCS makeup systems as part of efforts discussed in 3.13.
3.12 52 Provide discussion of pheromena and B6. See also ag and operator response on ATWS anu develop ah.
additional operator guidance.
3.12 w Provide guidance for achieving core B6 subtriticality via all means to insert control rods or to increase RCS boron concentration.
3.12 x Provide ATWS updating immediately as 9, 9a discussed in 3.3.
3.12 53 Operator error is adequately covered No action required.
since errors will be manifested as symptoms and will be treated accordingly.
GL 83-31 ID Description Disposition Section
, 3.12 54 Provide instructions for total loss of B4 AC power. Cover maintenance of a stable hot shutdown condition, plant cooldown, and depressurization.
Consider the presence of other accident i conditions such as LOCA and loss of RCP ,
seals. Provide battery and inventory l conservation measures to maximize the time available for AC power !
restoration. Provide whatever additional changes are needed as a result of generic issue USI A-44 ,
guidance. '
3.12 55 Provide alternate instructions to use BIO, 24 of pressurizer spray or the PORV for RCS depressurization. Address SGTR aspects (3.7) and HPI cooling.
3.12 56 AT0G part II discusses actions if sump B14 recirculation flow is blocked and cannot replace lost coolant. Such actions will be successful only if the RCS has no significant leaks below the DHR system suction elevation. Expand upon this, including the general topic of use of the LPI system to maintain RCS inventory, and provide operator guidelines.
3.12 57 Secondary pressure control is based on B10 turbine bypass and atmospheric dump valve operation. Provide other backup means to dump steam and to control the SG secondary pressure.
, 3.12 58 Expand the AT0G part II information as 41 - 45a outlined in 3.10 and provide guidance ,
to cover multiple failures in containment control systems.
3.13 59 Provide analyses as needed to indicate B13 which system parameters can be used to guide operator actions.
3.13 60 Provide analyses as needed to 813 demonstrate the feasibility of a recovery technique for some well
~
defined accidents.
3.13 61 Provide analyses as needed to optimize 60, 62 steps which have potentially adverse side effects such as increased loads on equipment and increased releases.
i 4
GL 83-31 ID Description- Disposition Section
.3.13 62 Provide analyses as needed to select 813 the best recovery paths.
3.13. 63 A sample listing of events that have No action required. '
been analyzed is provided in GL 83-31.
.3.13 64 Evaluate all calculations and assure 810 and B13. See they have.been extended far enough in also 60. ,
time to cover all significant portions '
of transients. Cover such items as cyclic repressurization of the RCS during small break LOCAs, establish time to cooldown during a SGTR, and show that operator actions are effective in establishing cooldown in a reasonable time with a reasonable ;
impact on the environment.
3.13 65 Verify the codes used to calculate NSSS B13. See also 60.
behavior by comparison to experimental systems data. Continue to provide adequate thermal / hydraulic quantitative data applicable to B&W systems.
Provide particular attention to unique i aspects of the design such as the hot leg and SG configurations.
3.13 66 Cover transients where known or B13 !
suspected unusual behavior is of concern. Include upper head voiding, j other RCS voiding, oscillatory flow ;
behavior in RCS, oscillatory pressure l behavior, and long term cooldown (as ;
identified in item 64). Examine ;
reasonableness of calculated behavior and assumptions.
3.13 67 Expand treatment of multiple failures 20 - 25, B13 l 4..
end provide' calculational support for SG tube rupture recovery involving ruptures larger than a single double-ended opening. _
3.13 68 Expand treatment of multiple failures B3, B11, B13 and provide calculational support for the NSSS response to RCP restart in a partly steam-filled system, particularly with respect to system pressure, void distribution, thermal stress, and CFT behavior. Include consideration of ICC conditions.
6 GL 83-31 ID Description Disposition Section 3.13 69 Expand treatment of multiple failures 34, 60, 68 and provide calculational support for recovery from a total loss of feedwater. Include restrictions for establishment of HPI cooling relative to SG secondary side emptying, pressure control of the secondary side (blowdown vs. attempts to maintain high pressure as long as possible), HPI capability, availability of electrical power, and SG tube stresses caused by differential thermal expansion resulting from HPI cooling. Provide emphasis on NSSS response when guidelines are applied, with evaluation of guidance effectiveness when confronted with various equipment failures and the influence of operator error.
3.13 70 Expand treatment of multiple failures Addressed in numerous and provide calculational support for above issues as well possible recovery methods from a small as such bins as B3, break LOCA with total loss of HPI. B8, B12, B13.
3.13 71 Expand treatment of multiple failures 70 and provide calculational support for means to reestablish primary to secondary heat transfer after hot leg voiding, including use of RCPs if not covered in item 67.
3.13 72 Expand treatment of multiple failures 84 and provide calculational support for NSSS behavior after a total loss of AC power and response to operator actions involving this topic. Provide additional operator guidance.
3.13 73 Expand treatment of multiple failures 70 and provide calculational support for long term recovery from small break LOCAs, including potential pressure and i temperature oscillations and their treatment following AT0G instructions.
3.14 74 Incorporate the results of 59 - 73 inte Addressed in numerous ATOG Part II as appropriate to provide .above issues. See the operator with an enhanced ,also B13.
understanding of HSSS response under various conditions. Emphasize RCS voiding and NC behavior, including conditions and phenomena leading to and resulting from loss of NC. ,
, i
- GL 83-31 ID Description Disposition 3 Section 3.14 . 75 Provideinterim item 74 coverage prior Closed by Ref. 2.
j to. implementation. Accomplished before implementation.
[
U 4 y ATOG represents a significant No action required.
- improvement.over current emergency
- operating procedures. Implementation
! of AT0G at operating reactors will :
'; provide a greater assurance of i'
operational rafety.
! 4 r Continue to improve and maintain AT0G. Accomplished during ,
' 1983-1994. See SER f for continuation discussion.
!, :4.1 76 AT0G is acceptable for development and Closed by Ref. 2.
- implementation of procedures when Extension was
- t. extended to provide additional ATWS and provided before NC guidance. implementation. ,
i' 4.1 77 ATOG extension as identified in 76 is Duplicates items that reqaired prior to implementation. See have been closed as ,
additional information of 3.3, 3.9.6, discussed above.
[ and 3.14.
- 4.2. 78 Address multiple failures, particularly Item 78 is separated ;
i with respect to SGTR. Provide guidance into components and i L for overfilled SG, for alternate RCS each is discussed :
i depressurization guidance ( articularly below. Note most SG -
- for PORV and spray failures , for issues are addressed j multiple tube ruptures in one and in in B10.
- both SGs, for better control of RCS-SG i- secondary fluid transfer, for improved
- long-term depressurization, for better
- control of environmental releases, and for alternate control of SG level.
B10, 17 and 25b See 4.2 78a Provide guidance for an overfilled SG
, with water in the steam lines due to . also 49 - 75.
L multiple failures.
F 4.2- 78b Provide alternate RCS depressurization B10, 24b See also
- guidance for multiple failure 18, 55, 49 - 75.
[ conditions including PORV and spray
- a failures. l i 4.2 ,
78c- Expand multiple tube rupture treatment B10, 22b and 23b See
- in one and in both SGs for multiple also 49 - 75.
- failures.
4.2 78d Provide batter control of RCS-SG B10, 20b See also 49
]
secondary fluid transfer. - 75.
4.2 7Be Provide improved long--term B10, 18 and 49 See
- depressurization, also 75
- - * , -,.a s v - --, , m. ..y.- e - - , . ..g-, 'rsm
, , _ ,-~ --wn-.
GL 83-31 ID Description Disposition Section 4.2 78f Provide better control of environmental B5, BIO, B14, B16, releases. B17, and B18. 21b closely related. 49
- 75 related.
4.2 78g Provide alternate control for SG level. B10, 17 and 25b.
4.2 79 Provide technical background and EPGs B5, B16. See also 8, for containment. 41 - 46, and 58 for examples.
4.2 80 Provide technical thermal / hydraulic B13. Provided in background, partict?arly for RCS voids; many sections of TBD extend to cover phenomena which impact and reviewed as part or potentially impact operation. of those sections.
Provide a credible quantitative basis. 81 - 85a are parts of 80.
4.2 81 Provide a quantitative basis and treat- B13, 80 ment of RCS voids, including the upper head.
4.2 82 Provide a quantitative basis and' treat- B13, 80 ment of plant response to depressurization via the PORV. Cover loss of NC followed by RCS repressurization and associated behavior.
4.2 83 Provide a quantitative basis and treat- 810, B13, 80.
ment of plant behavior during various Closely related to aspects of SGTR, including response to GL 83-31 Section 37 operator actions. items.
4.2 84 Provide a quantitative basis and treat- 813, 80 ment of long term response with particular attention to phenomena of interest expected beyond the time range provided by the present analyses.
4.2 85 Provide a quantitative basis and treat- 89, B13, 80. See ment of timing of HPI, particularly if also 34.
delayed and/or degraded.
4.2 85a Item 80 may need integral system data Integral data were to confirm calculated results. See obtained and also 78 and 86 - 98 where pertinent considered during TBD investigations may be needed. preparation. See, for example, Ref. 4.
4.2 86 See 3.2, 3.9.4, 3.9.6, and 3.13 for 87 - 89 plant cooldown and interfacing with non-emergency procedures.
GL 83-31 ID Description Disposition Section 4.2 86a Transfers between instruction paths in Obsolete since ATOG -
, cooldown EPGs should be reviewed to no longer used. I assure that internal loops without Problem does not exits and transfers into inappropriate recur in TBD.
or incorrect paths do not occur.
4.2 87 (Plantcooldownandinterfacingwith 4b non-emergency procedures. See 3.2, 3.9.4,3.9.6,and3.13,above.)
Interfacing to non-emergency procedures should be broadened and the means of transferring from those procedures to and from ATOG appropriately defined.
Operator error in procedure selection and in transferring should be addressed.
4.2 88 (Plantcooldownandinterfacingwith 32 non-emergency procedures. See 3.2, 3.9.4, 3.9.6, and 3.13.) HPI cooling effects on SG tube integrity should be evaluated.
4.2 89 (Plantcooldownandinterfacingwith B8. See also 4, 40, non-emergency procedures. See 3.2, 40a, 40b, and 59 -
. 3.9.4,3.9.6,and3.13.) Operation of 73.
the DHR system with the RCS saturated should be evaluated.
! 4.2 90 ATOG should be extended to cover 47 conditions other than reactor trip and power operation.
4.2 90a Provide coverage for any NSSS condition 48 that jeopardizes or potentially jeopardizes an identified barrier to release of radioactive material. (3.2, 3.11) 4.2 91 An acceptable alternate to 48a incorporation of items in ATOG is to provide a definition of the coverage in other plant procedures, interfacing information in the AT0G, and discussion of the rationale for locating the material in procedures other than AT0G with respect to coverage of conditions which occur at other than power operation. (3.2,3.11) 9 1
)
GL 83-31 ID Description Disposition
- Section 4.2 92 Perturbation of. instrument displays, B4. 6, 54, 69, and i
handling of unnecessary loaA, 72.
conservation of inventory, o tions to be taken upon power recovery, and plant cooldown/depressurization should be addressed- for loss of AC power. (3.3, 3.12,3.13) i 4.2 93 Aspects:of loss of AC power that are 6, 54, 69, 72, and 92 subject to. resolution of A-44.should be addressed following completion of A-44.
(3.3,3.12,3.13) i 4.2 94 Further actions to control ATWS which ag and ah !
utilize existing plant equipment should be considered and_ additional coverage
- and guidance for treatment of expected l phenomena should be provided. (3.3,
- . 3.12) 4.2 95 PTS guidance should be provided for the B7 l'
case where pressure / temperature limits, typified by Figure. 3, have been exceeded. (3.4,:3.9.4) j 4.2. 96 Post-ICC conditions with core damage B11, B18. Note also l should be covered consistent with 29.
l knowledge regarding degraded cores.
] Some aspects such as control of the plant with SGTR conditions can be covered now. (3.7,3.8) 4.2 97 Review of RCP. operation with respect to 5, 7b, lla, 16, k, trip, restart, and operation has not 26, 28, 30, 40, 46, 54, 68, and 71. See been completed due to publication of F GL 83-10e. also 97a. GL 83-10 review is complete.
I 4.2 97a There is a need for information B3. See also'16, regarding RCP operation when the RCS is 16a, k, 26, 28, 30, not in a subcooled condition. (3.3, 40,59 - 62, and 64 -
3.5,3.6,3.7,3.8,3.9.6,3.13) 73.
4.2 98 Guidelines which utilize the RCS 27 inventory . instrumentation should be 4
provided. (3.8) 4.2 99 ATOG Part I Section II Step 8.0 TBD Step 12 bases instructs the verification of "No ES provide the Alarms" when executing " Vital System clarification.
Status Verification" after a reactor trip. This statement should be clari-fied.to read "No ES Alarms or Conditions That-Require an ES Alarm."
GL 83-31 ID Description Disposition Section 4.2 100 AT0G Part I Section IIIB Step 6.1 TBD provides instructs that, for a " Lack of Heat appropriate guidance Transfer" with " lack of feed water in IIIB Step 3 and either subcooled or saturated," EFW to III.C Step 6 with both SGs should be initiated, but does reference to control not recognize that one SG may have been SG level, previously isolated. This condition should be addressed in AT0G.
4.2 101 AT0G Part I Section IIID Steps 11.5, B10. Note SG control 11.8, and 17.1 cover TBV use. ATOG has been completely should provide additional guidance for written in TBD and determining TBV availability and for order of preference cases when TBVs are not available. of TBVs is now clear.
4.2 102 AT0G Part I Section IIID Step 10 uses B14 the word "when" in its instruction.
AT0G must clarify if, by this instruction, it is intended to wait until the condition is achieved or if execution of subsequent steps is to be continued.
4.2 103 AT0G should justify the use of PORV B8 operation in Part I Section CP-102 Step 4.3 for depressurization in preference to use of an auxiliary pressurizer spray (for plants equipped with high pressure spray capability).
4.2 104 With regard to the guideline tests to Specific to AT0G and be used by the operator to verify NC does not recur in and heat transfer, AT0G should address TBD.
apparent inconsistencies (Part I Section CP-103 Step 4.2 vs. Section CP-104 Step 10.1).
4.2 105 AT0G should resolve the inconsistency Specific to ATOG and between Part I and Part II Table 3 in does not recur in selection of parameters to govern SG TBD.
inventory control decisions.
4.2 106 AT0G Part II Table 46 has omitted all TBD coverage of containment parameters except pressure containment differs as key indicators. ATOG should provide significantly from additional guidance to reflect the ATOG. See also B5 other parameters. and 816.
4.2 107 Analyses should be provided or B13, 34, 69. Note referenced to support the HPI AT0G Part II is performance discussion in ATOG Part II obsolete.
Chapter D page 99. (The referenced item is time from full power operation when decay heat is matched by one or by two HPI pumps.)
J GL 83-31 ID Description Disposition Section 4.2 108 AT0G Part II ICC discussion (page 116) 29,39,abd96. Note states that "special cooldown AT0G section is precautions-need to be followed to obsolete.
contain contaminants." The need for i these special precautions should be '
identified in the applicable locations in AT0G Part I as requiring plant specific evaluation and additions.
4.2 109 The method for reactor building AT0G Part II is '
temperature monitoring _ identified in obsolete, i AT0G Part 11 Section 3.5 page 220 should be justified as representative !
and its use explained. l 4.2 110 The AT0G Part II page 267 discussion of Condenser is plant- i loss of "Offsite Power /RC Pumps Not speci fic. AT0G Part ;
Running" should provide additional II is obsolete. l guidance on the capability and operation of the condenser.
4.2 111 AT0G Part II Appendix E page E-9 Obsolete l instructs that seal injection or CCW !
must be restored to RCPs within 60 l seconds or the RCPs must be tripped.
This requirement should be justified with regard to its adequacy for the hardware involved and the capability of the operator to execute the required actions.
4.2 112 AT0G Part II Appendix F introduces the Term no longer used.
term " boiling pot mode" which should be clarified to be consistent with the remainder of ATOG.
4.2 113 AT0G Part II Appendix F uses terms B14 "very rapidly" and " slow" . These terms do not reflect a mutually consistent time frame and should be quantified.
4 4.2' 114 ATOG Part II Table F-3 indicates that B11. Note ATOG Part !
superheated conditions can be expected II is no longer used.
l for up to 10 minutes after a large '
break LOCA and that ICC need not be entered. Justification. for the 10 minutes should be provided and further discussion should be submitted to
- address why this instruction will not ;
i lead to procedures calling for either a premature or late entry into ICC. )
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GL 83-31 ID Description Disposition
. Section 4.2 115 AT0G Part I Section IIIA Step 6.0 has AT0G no longer used. l been revised to instruct the operator See SER Section 3.3.5 to enter the ICC section if superheat for applicability to is indicated by.incore thermocouples TBD and disposition. '
(replacing coincidence indication by I
- the incore thermocouples and hot leg. i RTDs). Clarification, revision and/or '
justification should be provided for j
^
other AT0G sections (including III, I items 4.1 and 4.2, CP-103, item 8.0, l and Figure IIIA) in which indications ;
utilized for ICC are not consistent 1 with revised Part I Section IIIA step 'l 6.0. -
4.2 .116 Figures A-7, C-3, D-9, and E-4, revised Figures are no longer per the discussion in the March 14, used. l 1983 letter, Attachment A, should be :
provided to confirm resolution of l associated clarification / consistency ;
items. 1
.4.2 aa The examples cited in most cases are Addressed by the intended only to clarify the concern, staff during the and are not intended to identify all review reported 4 instances where the concern occurs in herein.
AT0G. As part of the resolution of these items, the B&W Owners Group should assure that all instances have been addressed.
4.3 ab The EPG approach is symptom oriented. Staff conclusion for It provides an adequate mitigative which no action is strategy that is independent of early needed. ;
event diagnosis. '
Staff conclusion for 4.3- ac AT0G provides sufficient guidance that it can be' translated into acceptable which no action is ,
E0Ps using the process identified in needed.
ad Address any revisions necessary due to B7 i NRC review under USI A-49.
The following items are-defined in a staff communication (Ref. 2) regarding
- followup to GL 83-31 (Ref. 5):
- af We require that AT0G be revised to B6 address any additional considerations identified by the pending Commission rulemaking on ATWS.
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GL 83-31 ID Description Disposition Section ag Letdown is indicated whenever ATWS 86 exists. This is acceptable when there is adequate SCM. It should be justified for a saturated RCS at high pressure, such as when code valves are open with RCS inventory being lost due to boiloff.
ah Letdown during ATWS should be examined B6 further, considering such items as temperature coefficient as a function of time in life, RCS injection rate, boron transport, power generation rate, core voiding, core overheating, and overall inventory behavior. Special circumstances such as no feedwater, no safety injection, no charging, and loss of natural circulation should be considered.
ai Opening the PORV may not rectify a loss 14, 34, 34a, 82, 83, of NC when there is a void in the candy 88, 89, B12, B13 cane. The rationale for this instruction should be reexamined and justified in the longer term, or the instructions should be modified. The justification should address : (1) propriety of the instruction for scenarios in which safety injection and charging are not operating, (2) interaction of this guidance with prior instruction to bump pumps (which have the potential to restore NC if feedwater is available), and (3) necessity for use of the RCS feed-and-bleed cooling mode while feedwater is available (producing complications of water in containment and switchover to recirculation cooling).
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REFERENCES
- 1. Ward, L. W., " Draft Technical Evaluation Report on Resolution of AT0G SER Items - LWW-26-88," Letter to Harold Polk, Project Manager, NRC from Idaho National Engineering Laboratory, August 30, 1988.
- 2. Crutchfield, Dennis M., " Abnormal Transient Operating Guidelines (TMI Action Item I.C.1)," Letter from Chief, Operating Reactors Branch #5, NRC to Daniel D. Whitney, Chairman, Operator Support Subcommittee, B&W Owners Group, December 14, 1983.
- 3. " Clarification of TMI Action Plan Requirements," NRC, NUREG-0737, November 1980; NUREG-0737 Supplement No. 1, January 1983.
- 4. " Technical Advisory Group Investigation of Once Through Steam Generator Thermal Hydraulic Experimental Data Requirements,", B&W BAW-2079, March 1989.
- 5. Eisenhut, Darrell G., " Safety Evaluation of ' Abnormal Transient Operating Guidelines', (Generic Letter 83-31)," Letter from Director, NRC Division of Licensing to all operating reactor licensees, applicants for an operating license and holders of construction permits for Babcock
& Wilcox pressurized water reactors, September 19, 1983.
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