ML20024E953

Safety Evaluation Supporting Amend 75 to License DPR-59

ML20024E953
Person / Time
Site:	FitzPatrick
Issue date:	08/26/1983
From:	Office of Nuclear Reactor Regulation
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ML20024E952	List: ML20024E951 ML20024E953
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NUDOCS 8309070478
Download: ML20024E953 (20)

Text

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UNITED STATES 4

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WASHINGTON, D. C. 20555 a

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SAFETY EVALUATION'BY THE OFFICE-0F NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.75 TO FACILITY OPERATING LICENSE NO. DPR-59

_P_0WER AUTHORITY OF THE STATE OF NEW YORK JAMES A. FITZPATRICK NUCLEAR POWER PLANT DOCKET NO. 50-333 I.

Introduction By letter dated July 7,1983, the Power Authority of the State of New York (the licensee) proposed changes to the Technical Specifications for

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Facil'ity Operating License No. DPR-59 for the James A. FitzPatrick Nuclear Power Plant. -These proposed changes. involve:

(1) Revised operating limits as a result of the long-term modifications to the Scram Discharge Volume (SDV);

(2) Removal of license conditions for the continuous monitoring system of SDV water level imposed by the Commission's Order of October 2, i

1980; and for the air dump header imposed by the Commission's Order of Janua' y 9,1981; and r

(3)

Fulfillment of license conditions for implementation of the long-term SDV modifications imposed by the Commission's Order of June 24,1983.

II.

Discussion The first change proposed by the licensee reflects the modifications to the SDV system to improve hydraulic coupling and provide diverse instru-mentation.

These modifications have been undertaken during the refueling outage for Cycle 6 operation to comply with the design and performance criteria described in the staff's December 1,1980 Generic Safety Evaluation Report (Generic SER), "BWR Scram Discharge System". Change (2) above, removes the license conditions for the air dump header instrumentation and continuous water level monitoring because the improved hydraulic j

coupling achieved by the modifications noted in change (1) above.

Change (3) above,. acknowledges that the licensee has-fulfilled the conditions imposed by the Commission's Order of June 24, 1983 by implementing the modificatitns discussed in change (1).

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After a'nalyzid'g events at several operating reactors that involved the SDV system, the staff recommended that SDV systems in all BWRs be modified to assure long-term reliability.

To achieve these objectives, an NRC. task

. force and a subgroup of the BWR Owners Group. convened to develop revised

- SDV system design and safety criteria to be used in establishing acceptable

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SDV system modifications.

Short-term and long-term actions were recommended by the staff in the Generic SER. The staff evaluated the licensee's actions under the short-term phase of the program in a January 29, 1982 license amendment. The January 29, 1982 amendment revised the Technical Specifi-cations by adding surveillance requirements for the vent and drain valves and level switches in' the instrument volume.

The staff also issued Orders which implemented license conditions for an automatic scram function from degraded air supply conditions and for continuous monitoring of SDV water

. levels as interim measures until the long-term modifications for improved hydraulic coupling were implemented.

The long-term program identifies improvements in three' major areas: SDV Instrument Volume (IV) hydraulic coupling, diverse level instrumentation, and system isolation. The Generic SER states the various criteria, the r

technical bases, and an acceptable means.of compliance. This Safety Evaluation summariz s the staff's review of the actions taken by the licensee under the long-term program.

.III.

Evaluation A.

Change (1) - SDV Modifications We have reviewed the licensee's submittal to determine compliance with the 4

design, safety', functional and ope' rational criteria of the Generic SER by evaluating them against the stated acceptance criteria in the Generic SER.

Our evaluation of the licensee's implementation of long-term modifications and associated technical specification changes to improve the SDV reliability at' FitzPatrick is discussed below.

For reference, the numbering system used to evaluate each criterion parallels that of the Generic SER.

4.2.1 Functional Criterion 1 The scram discharge volume shall have sufficient capacity to receive and contain water exhausted by a full reactor scram without adversely affecting control rod drive scram performance, i

Licensee Response As modified, the SDV system p'rovides a controlled near-atmospheric volume for the accumulation of scram discharge water which is released from each control rod Hydraulic Control Unit (HCU) upon initiation of a reactor scram.

There' are 69 HCU's on the east side of the Reactor Building and 68 HCU's on l

the west side.

The near-atmospheric volume available for scram located in the SDV above and near each bank of HCU's provides 3.34 gallons per HCU

_during the worst-case fast-fill event 4

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Each Instrument f.'clume (east and -west)1has fcur -scram level instruments individually 1cennected via.one-inch. diameter lines and root valves.

The scram 1evel specified in. the proposed. Technical. Specifications (accumu-

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.lation of 34.5' gallonsLinLthe-24-inch diameter' Instrument Volume) has been determined utilizing results - from open-channel -flow analysis and RPS system time delay in' the scram l outlet valve ' actuation. -No credit is~ taken for this volume-to accommodate a scram.

Thus, adequate volume for scram,-

under the worstTconditions, exists in:the. modified system.

1 Staff Evaluation LAn-acceptable means of meeting this -criterion is to provide a minimum scram discharge volume:of -3.34 gallons per drivelin accordance with the

. General' Electric letter OER 54, dated March 14,1982,-which we previously found acceptable.'

We have reviewed the licensee's response against the requirements of the'-

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acceptance crite'rion.and-have determined that the licensee has used the sizing criterion of-3.34--gallons per drive.

Based on the data presented.

.above, we conclude that the SOV high water level' scram setpoint of < 34.5-

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-gallons has beenL conservatively selected and provides sufficient margin under worst case conditions. Therefore', the desi gn modi fications ' meet the recuirements and.are acceptable.. Based on-the above, the proposed change Ltc the ' Technical Speci.fications which: sets the. scram setpoint of. j[34.5

' gallons. is acceptable.

4.2.2 Safety Criteria 4.2.2.1 Safety-Criterion 1

No single active failure of aLcompunent or Lservice function shall prevent

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a reactor scram under the most degraded conditions 1that are operationally.

acceptable.

-Licensee Response-4 In regard to the operation under degraded conditions, this project has addressed the occurrence of low air pressure in the CRD control air headers.

i-Operation under degraded control air conditions could result in 'a Scram Discharge Instrument ~ Volume " fast. fill" event.

The hydraulic design incorporated in this.long-ter.m modification addresses this " worst case" si tuation.

In addition, NRC Regulatory Guide 1.53 requires that no credible single.

failure result in the inability of a protective system to perform its intended safety related function. The' Scram Discharge Instrument Volume (SDIV) electrical power and control and instrumentation is designed on a redundant basis.

All wiring, conduit and' cable / raceway runs are physically separated to prevent a: single physical or electrical failure from isolating

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• -c S" *n a reactor scram or on a1 high level signal in the SDIV.

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i dsnt cod:r:1 air lines are routed from the SDIV air dump solenoid valves

sEthe redundant. vent and drain isolation valves. _The SDIV level measuring ir.struments are provided with redundancy'and diversity as described under Sa fetyl Criterion No. 3.

Alsi. Jir. i s response.to Design Criteria Ll.below. the licensea iescrite:

e syste ces'cn si h respect to the worst-case in-flow rates and states

-~;"a: - he~ syster was sized to accommodate such an event.

7ent and drair.

' lows ~ are' not necessary to assure system function.

Staff Evaluation An-acceptable means of complying with!this criterion is to design the system such that partial losses of service function (e.g., degraded control air pressure) as well as. full losses do not adversely affect system functions.

Na have' revie. sed the licensee's response against this acceptar.ce criterion anc aga'ns: the criteria for Design;Cr~iterion 4 We find that the licensee's casign as, described above meets the requirements and is therefcre, acceptable.

t.2.2.2 Safety ~ Criterion 2 N: sir.gle active failure shall prevent uncontrolled loss of reactor coolant.

Licensee Response The.criter, ion establishes the design basis for preventing loss of reactor coolant ldue to a single : failure in' the SDIV system.

It fu'rther states an

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! acceptable way of meeting this criterion is to install two isolation valves in series for uthe vent and drain function.

Two isolation valves are installedJin series. for-the vent.and drain functions to prevent a single failure'of a valve from preventing the isolation of the vent or drain. An uncontrolled loss of reactor coolant due to single isola-t

-tion ' val ve failure-to-close is thus prevented.

Two control air lines are routed.from the scram solenoid valves to the redun-bnt vent and drain' isolation valves.

A single failure-in one control air line will not prevent the other ^ control air line from closing the redundant

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. isolation valves.

The 115 volt a-c scram solenoid valves are backed up by 125 volt d-c. solenoid valves powered from the station battery.

A single failure of one of the 115 volt a-c ' solenoid valves will not, therefore, prevent ~the isolation valves from closing.

Staff Evaluation An acceptable way'of meeting -this criterion is to provide two isolation valves in series in 'all SDV vent. and IV drain lines which are sufficiently independent to avoid failure due:to~. solenoid failures.

This resolution will also correct' the potential for excessive hydrodynamic force generation.

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We have evaluated the licensee's modification against this criterion and have concluded that the licensee har designed the system in accordance with the criterion and is therefore acceptable.

4.2.2.3 Safety Criterion 3 The scram discharge system instrumentation shall be designed to provide redundancy, to operate reliably under all conditions, and shall not be

. adversely affected by hydrodynamic forces or flow characteristics.

Licensee Response Each SDIV is provided with level measuring instrumentation which meets the requirement for redundancy and diversity.

Each SDIV has two float type level switches and two differential pressure type level instruments for actuating a scram on high SDIV level.

Float switches and differential pressure actuated switches are arranged electrically in an "or" gate logic so that a failure of one type of measurement due to a common mode failure

, will not result in the inability to initiate a reactor scram on high SDIV level.

The level switches are arranged in a one-out of two taken twice logic arrangement.

Therefore, the instrumentation on each SDIV meets the single failure criterion.

A Hydraulic Transient Analysis was made to determine the possible impact of hydrodynamic forces in the system.

The effect of the hydrodynamic forces has been incorporated into tNe design of the two types of instrumentation used in this design.

In addition, the impact of flow characteristics has been determined and incorporated into the specification of the instrumenta-tion which may be flow sensitive, i.e., the float-operated level switch.

The level sensors provided for each Trip System are of two diverse types.

The float operated level switch (class lE qualified) is s'milar in operation i

and construction to that which is presently in use. The second type of level sensor is a sealed sensor system with a differential pressure trans-mitter which has operating principles totally different from that employed by the flow-operated level switch. This diverse instrumentation is com-pletely class lE qualified and provides assurance of protection from common.

cause failures due' to float-crushing, etc." Alsd,the possibility of a common cause failure is furthe'r protected against by: (1) the periodic functional testing of level instrumentation as required by Surveillance Criteria 2 of the NRC SER, (2) the operational principal diversity, and (3) the qualification of instruments to IEEE 323 and 344.

The redundant instrumentation is powered from separate and redundant vital 115 VAC electrical busses such that a loss of electrical power.in one bus will not cause an unnecessary scram.

The electrical system is arranged so that Bus "A" powers the "A" system instruments and relays and Bus "B" powers the "B" system instruments and relays.

A failure of either of these busses will cause a half scram.

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Staff Evaluation An acceptable means of complying with t'his criterion and addressing the

. additional staff concerns on common-cause failure of instrumentation is as follows:

- (l)- With respect to~ single failures-(random) provide sufficient

redundancy in the automatic scram level instrumentation to meet the single failure criterion on each instrumented portion of the.SDV; and (2).With. respect to common-cause failures:

.a.

provide additional (or substitute) level-sensing instrumentation for the automatic scram function to include diversity as well as redundancy.

The diversity, should, as a minimum, be achieved by: level sensors that employ different operating principles for measuring the water level; and b.1for the instrumentation delected, demonstrate how common-cause failures, such as.those identified by operating history and those identified in the Foreword to IEEE 379-1977 will be considered.

We have evaluated the licensee's response to this safety criterion and find

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.that sufficient redundancy has been provided to meet the single failure

- criterion.

As stated.in the lice'nsee's response to Safety Criterion 1, redundant components in the scram discharge system assure that failure of a single valve, instrument, or other component will not prevent a reactor scram..In addition, the. licensee's response to Design Criterion 4 (below) states' that each instrumented volume will be equipped with two sets of instrument taps.

As-stated 'in the licensee's response to Safety Criterion

3. both -float-type and differential pressure sensing type level-instruments will be installed thereby providing both redundancy,and diversity.

With respect to common-cadse failures, the licensee has provided for diver-sity by using differential pressure and float-type instrumentation.

The i-pressure-differential switches are not susceptible to the hydrodynamic

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- forces experienced with crushed floats.

Therefore, we find that sufficient diversity' has 'been provided for and that each type of sensor uses different principles "for sensing water. level.

For these types of instruments, the licensee has considered common-cause failures as _ identified by previous operating history and by the Foreword to IEEE 379-1977._ Operating history has shown that floats could be crushed because of hydrodynamic forces. As discussed above, the licensee has installed diverse instrumentation to account for this problem.

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'Too protect the instrument from common-ca'use failures. resulting from the external _ environmental effects, the-Foreword tc IEEE' 379-1977 suggests that system components be designed, qualified and installed to be immune from

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earthquakes and floods, design and manufacturing errors, and operator and maintenance errors.. The licensee has stated that the equipment will meet'IEEE Standards 323.and 344.

Since the licensee will' be installing safety-related equipment, Appendix B of 10. CFR Part uSO, Quality. Assurance Criteria : for Nuclear. Power : Plants and Fuel Reprocessing Plants, requires,

in part, that licensees assure'that manufacturers who provide equipmeat for use in safety-related applications.have design and manufacturing quality assurance programs consistent with Appendix B requirements.

Therefore,

Jthe'use of safety-related equipment in the SDV modifications and the use of qualified maintenance personnel who use approved procedures subject to a quality' assurance program, all meet the intent of the IEEE Foreword and, are-therefore acceptable.

We have reviewed the licensee's proposed changes to the Technical Specifi--

cation Limiting Condition for Operation and surveillance requirements regarding RPS and' rod block instrumentation and find them acceptable because

'they incorporate both the float and differential pressure type instruments.

4.2.2.4 Safety Criterion 4 System operating conditions which are required for scram shall be continuously moni to red.

' Licensee Response The SDIV is measured by redundant.and diverse level instrumentation as described in our response to Safety Criterion 3.

In addition, the control room operator is provided with appropriate annunciators, computer printouts, and status indicating lights.

Staff Evaluation An acceptable means of complying with this criterion is provided under Safety Criterion 3.

Since diverse and redundant instrumentation will be installed, and the licensee's response was found acceptable for Safety Criterion 3, we therefore, find this item is also acceptable.

4~.2.2.5 Safety Criterion' 5 Repair, replacement, adjustment, or surveillance of any system component shall not requi.re the scram function be bypassed.

Licensee Response When a level device is removed. from service, the device will be bypassed.

Float level switches and analog type (differential pressure) switches on

. each Instrument Volume in each channel are combined in a logic "or" gate such that bypassing any one switch will not prevent actuation of the asso-ciated prot'ective channel.

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- Staff Evaluation

- An acceptable way of complying with this criterion is for instrument (or instrument channel) repair or replacement to: implement a half-scram-(one-out of 2) in accordance.with existing Technical Specifications.

We-have evaluated the licensee modifications against this criterion and have determined that the system has been. designed in accordance with' the

• criterion based on the use of a "one-out-of-two taken twice" logic system and is.therefore acceptable.

' 4.2.3 Operational Criteria The techn'ical-basis on page 42 of the~ Generic SER states that these criteria

- are based upon operational convenience and are not directly related to safety given that both the hydraulic coupling between the SDV and IV is sufficient e

to. quickly detect an accumulation of water in the volume and the instrumen--

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. tation available to detect the water is extremely reliable.

For example,.

operational criteria 1 and 2 are meant to prevent inadvertent scrams.

resulting from maintenance and test' operations and to assure that the.

operator _ has enough _information available to permit him to take ccrrective action prior to conditions-which would cause an inadvertent scram.

Simil a rly, operational criterion 4 would facilitate placing the plant back in operation after a scram.

Yet,.these criteria are indirectly, related to safety in that they prevent unnecessary challenges to the safety systems and so should be 4

foll owed.

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4. 2. 3.1 ' Operational Criterion 1 Level instrumentation -shall be designed to be maintained,. tested, or cali-brated during plant operation without causing a scram.

Licensee Response The level instrumentation is designed to be maintained, tested or calib. rated-during plant operation without scram as discussed in the response to. Safety ',

Criterion 5..Each instrument can be tested locally with proper function.

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.of respective relays, alarms and _ computer messages assuring full operational L

readiness.

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ile have reviewed'the licensee's response that the level instrumentation has been_ designed to allow maintenance,_ testing, or calibration during plant c

operations without causing a scram and conclude that the' requirements for-

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.this criterion have ~ been met.

4.2.3.2 Operational Criterion 2 4

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- The system shall include sufficient supervisory instrumentation and alarms to permit surveillance of system operation.

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Licensee P.esocnse Level instrumentation is' provided with control room annunciator alarms and ccmputer printouts to permit control room surveillance by the operators as follows:

1)

Annunciator Inputs

- One common annunciator window for "HIGH LEVEL SDIV SCRAt!" on any one of 8 scram level instruments 4 float switches and 4 differential pressure actuated switches.

- One annunciator window to indicate "SDIV NOT DRAINED".

This window is activated from either one of two slave trip units which are activated by their respective differential pressure transmitters en the attainment of the high level alarm point.

There is one alarm function associated with each of the SDIVs.

.One annunciator window to indicate "HIGH SDIV TRIP BYPASSED" if bypass is selected in shutdown or refueling mode.

2)

Comouter Inputs

- One computer input for each of 8 level instruments - 4 float switenes and 4 differential pressure actuated switches.

Indica-tion is "Hi Level SDV Trip".

- Two computer inputs to indicate " Rod Block Withdrawal".

(One at each SDIV)

- Two computer inputs to indicate water level at " Alarm" condition.

(One at each SDIV) 3)

Status Indicating Lights

- One indicating light for "0 PEN" and.one for " CLOSED" from each SDIV vent andidrain valve.

Open = Red, Closed = Green.

A total of 16 lights is provided, 2 from each of 8 valves.

Staff Evaluation-We have reviewed the licensee's response and find that it meets the criterion and is, therefore, acceptable.

4.2.3.3 Operational Criterion 3 The system shall be designed to minimize the exposure of operating personnel to radiation.

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Licenses Response The piping system is designed to minimize operating personnel exposure to radiation hazards.

To assure minimal exposure of operating personnel tc radiation hazards, the IV.will be designed to accept temporary shielding and the vent line design will incorporate a protected, non-submerged dis-charge.

In addition, hydrolase connections are provided at critical areas of the drain and SDV headers-to permit clean out.

Further, the IV and the drain line are provided with concrete block shielding enclosures.

Staff Evaluation We have reviewed the licensee's response and find it is acceptable because the system has been designed. to minimize radiation exposure to operating personnel.

4. 2. 3.4 Operational Criterion 4 Vent paths shall be provided to assure adequate drainage in preparation for scram reset.

Licensee Response The vent path provides adequate drainage at reset.

The piping design will, assure adequate venting.

There will be a one inch diameter comment vent from both the SDV header and.the instrument volume.

, Staff Evaluation We have reviewed the licensee's response and find that adequate drainage has been provided because of improved hydraulic coupling as discussed in our evaluation of Functional Criterion 1 above and the venting capability described above.

4'. 2. 3. 5 Ooerational Criterion 5 Vent and drain functions shall* not be adversely affected by other system interfaces.

The objective of this requirement is to preclude water backup in the scram instrument volume which could cause spurious scram.

Licensee Response Vent and drains will not be impacted by other system interfaces. The 2-inch diameter drains will be routed independently -to equipment drain headers (four inches) which, in turn, travel to the lower elevation eg'uipment drain sumps to ensure highly reliable drainage.

Since no increase in drain flow is expected and, in fact, is now split two four-inch diameter drain headers, there is no impact on plant drainage system.

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The vents are* provided with non-submerged discharge via a water knockdown chamber in the protected environment of nearly RHR heat exchanger rooms.

This vent discharge arrangement is presently in operation at the facility and there are no operational problems regarding it.

Staff Evaluation We have reviewed the licensee's response and find that the system design is adequate to preclude water-backup and therefore avoids spurious scrats.

4.2.4 Design Criteria 4.2.4.1 Design Criterion 1 The scram discharge headers shall be sized in accordance with GE OER and shall be hydraulically coupled to the instrumented volume (s) in a manner to permit operability of the scram level instrumentation prior to loss of sys tem function.3 Each system shall be analyzed based on a plant-specific maximum inleakage to ensure that the system function is not lost prior to initiation of automatic scram.

Maximum inleakage is the maximum flow rate throug'n the scram discharge line without control rod motion summed over all control rods.

The analysis should show no need for vents and drains.

Licensee Resconse The scram discharge volume (headers, connection from header to instrument volume and available portions of the instrument volume) are sized per GE 0ER-54 for 3.34 gallons per'HCU coincident with the worst case in-flow rate determined from plant-specific open-channel hydraulic analysis.

The worst case in-flow rate of 6.4 gpm per rod was determined from stall flow tests conducted by.the licensee.

The open channel analysis utilized this value, for inleakage rate summed over all the control rods connected to a header.

Vent and drain flows are not necessary to assure system function.

.Sta ff Evaluation We have evaluated the licensee's response and have determined that the licensee has provided an IV which is an integral part of. the SDV for each-of the two SDVs, thus assuring adequate-hydraulic coupling.

The licensee has also designed the _ system in accordance with the approved GE reccmmend-ations and has performed the supporting analyses.

We therefore find that the licensee's response meets this design criterion and is acceptable.

We have also reviewed the licensee's proposed changes to the rod block set-point of < 26.0 gallons and conclude that this setpoint is acceptable.

Leakage beyond this point will automatically result in a reactor scram.

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4.2.4.2 Design Criterion 2 Level instrumentation shall be provided for automatic scram initiation

- while sufficient volume exists in the scram discharge vclume.

Licensee Response Des!gn and analysis procedures have established instrument settings such that automatic scram initiation will occur with. sufficient margin to assure that un adequate scram discharge volume present.

Level _ instrumentation is both redundant and diverse.-

Staff Evaluation Acceptable compliance with Design Criterion 1. is an acceptable means of complying with this design criterion.

Having found the licensee's response to Design Criterion 1 acceptable, we find that this item is also acceptable.

4.2.4:3 Design Criterion 3 Instrumentation ' taps shall be provided on the vertical instrument volume -

and'not on the connected piping.

Licensee Response The design provides two sepa* rate taps directly to the Instrument Volume for each level instrument, not on the connected piping.

Staff Evaluation We have reviewed the licensee's response against this criterion and have determined that the instrumentation taps have been previded on the vertical IV and not on the connected piping.

This-is in accordance with the Generic

- SER criterion a'nd is therefore acceptable.

Ir.' addition, this criterion also requires that the functional tests of the level instrumentation be acceptable.

These functional. tests should be per-.

- formed after each scram for switches using water since there remains concern for residual common-cause failures.

However, the model TS also provide for:

an alternate test frequency when diverse level instrumentation is employed.

Because new diverse instrumentation has been' installed, the ' licensee.has' elected to perform functional testing on a monthly basis rather than after o

each scram.

Based on having installed the design modification in accordance with the Generic SER criteria, we find the licensee's proposed surveillance frequency to be.in accordance with our guidelines 'and is acceptable.

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Desien Criterion 4 The" scram instrumentation shall be capable of detecting water accumulation

- in the instrumented volume (s) assuming a ~ single active failure in the instru-

. mentation system or the plugging of an instrument line.

Licensee Response:

The single failure of level instrumentation is addressed in the licensee's' response to. Functional Criterion No.1.

J All uinstrument taps are connected directly 'to the Scram Discharge Instrument -

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Vol ume.

This reduces or. eliminates the possible accumulation of sediment which could plug the instrument sensing lines.

Functional testing of the instrumentation of each SDIV in accordance with the technical specifications provides an additional level of assurance that plugging of the sensing lines ~will not occur.

The sensing line. instrument isolation valve taps are located on the SDIV at different orientation to prevent a single ~ plugging incident from disabling all instruments. The analog differential pressure transmitter is provided

- with' sensing taps completely independent from the float level switches.

Additionally, the differential pres ~sure type instruments have a filled

. capillary. sensing system which prevents sediment from reaching the instrument sensing mechanism.

' Staff Evaluation L

An acceptable means of meeting this criterion is to satisfy the requirements i

under Safety Criterion 3 and to install the instrumentation in such a manner that no' credible active.or passive failure can significantly impact the ability l

_.of the instrumentation to monitor the SDV'for the presence or accumulation of water.

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. The licensee' has satisfied the requirements of Safety Criterion 3.

In addition, as discussed above, the scram level instruments will be installed such that no credible active or passive' faiiure can significantly affect its ability to detect water.

Since each instrument volume. has two sets of instrument taps, parallel ~ hydraulic circuits exist and therefore plugging 4

of one line or. failure of a single instrument will not prevent scram

.ini tiation.

Therefore, we conclude that the licensee meets the requirements of this criterion.

4.2.4.5 Design Criterion 5 Structural-and component derign shall consider loads and conditions including '

those due to fluid dynamics, thermal expansion, internal pressure, seismic i

. consideration and adverse environment, i;

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-ic-Licensee Resoonse The piping, pipe supports, instrument volume / supports, instruments, conduit and block wall enclosures have considered loads due to fluid dynanics, thermal expansion, internal pressure, seismic consideration and adverse environment, as required.

Staff Evaluation We have reviewed the licensee's response and find that the structural and component design h!ls) considered the loads and conditions required by the criterion and is, therefore, acceptable.

4.2.4.6 Design Criterien 6 The power-operated vent and drain valves shall close under loss of air and/or electric power.

Valve position indication shall be provided in the control room.

Licensee Resoonse All air operated SDIV vent and drain valves are of the air to open/ fail close type.

A loss of control air, control air tubing break or loss of both channels of vital 115 VAC which operate solenoids SV-31 A & B will result in. automatic spring-assisted closure.of the air operated valves.

Each air operated vent and drain isolation valve is provided with a green and red indicating light.on :the main control panel to indicate closed and open position', respectively.

At intermediate positions of the valve, both 1ights will be illuminated.

Staff Evaluation We have evaluated the licensee's requirement and conclude that the requi* ;-

ments of this criterion have been satisfied.

4.2.4.7 Design Criterion 7 Any reductions in the system piping flow path shall be analyzed to assure system reliability and operability under all modes of operation.

Licensee Response No reduction in flow area occurs in the SDV headers or SDV header to IV piping.

The headers are 8 inch diameter along the legs of the "U" and are 10-inch diameter at the cross piece of the "U".

A 10 inch diameter pipe connects each of the headers with its respective instrument volume.

The instrument volumes are 24 inches in diameter.

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Staff-Evaluation This criterion requires.the anal.ysis of piping systems when a reduction in the. available flow area is caused through a. reduction.in ciping diameter

.in the SDV and.SDV to SDV-IV piping.

For lines less -than two-inch inner diameter the staff has. traditionally required that hydraulic line plugging be assumed as a single failure.

Therefore, acceptable system _ function must be ~ demonstrated, given this potential single. failure.

The licensee has addressed _this issue-by stating that there is no reduction in flow area in'the SDV heads or in the SDV header to.IV piping.

Plugging of. a single instrument, vent or drain line is considered a single failure, which_ is addressed in the response to Safety Criterion 1 and Design Criterion 4

We have reviewed the licensee's response to this criterion and to the two other criteria referenced above and conclude that the requirements for this criterion have been met.

4.2.4I8 Desien Criterion 8

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System piping geometry (i.e., pitch, line size, orientation) shall be such l

that the system drains continuously during normal plant operation.

Licensee Response The piping for the SDV headers, the SDV header to IV. piping, the drain and

' the vent piping are.all' sloped at. least.1/8 inch per foot downward thus providing for continuous free draining of the SDV.

Staff Evaluation This criterion. addresses the need to provide a flow path which permits the.

continucus draining of coolant that results from normal rod leakage past the individual scram outlet valves.

It requires a positive downward slope of the SDV and associated drain piping, as well as piping that is free of loop seals and adequate in size, to prevent buildup of water in 'the SDV.

This criterion must be satisfied to ensure the assumptions used in the analyses for system function under Design Criterion 1.

We have reviewed the licensee's response and find that the system has been

-designed such that it continuously drains during normal plant operation.

-Since the requirements to this criterion have been satisfied, the assumptions

.to the system functional analysis used in Design Criterion 1 have been ensured.

'We, therefore, find the licensee's ' response to this criterion acceptable.

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-if-4.2.'.9 Design Criterion 9 Instrumentation shall be provided to aid the operatcr in the detection of wa er a canulation in the instrurented volumes prior to scram initiation.

Licensee Response Annunciators and computer printouts are provided for the operator to determine the occurrence of water accumulation in the SDIV prior to. scram initiation.

Additional information is provided in the licensee's response to Operational Criterion 2.

This design criteria permits the present alarm and rod block withdrawal alarm to meet the requirements for surveillance provided that an acceptable hydraulic coupling exists.

The hydraulic couplin'g of the scram discharge volume and the IV has been addressed in the licensee's response to Functional Criterion 1.

Staff Evaluation The water level alarms notify the operator when water is present in the ins trument volume.

The rod block instrumentation notifies the operator that the water level is continuing to rise and prevents further control rod with-drawal.

The licensee has proposed changes to the TS that will reflect the revised rod block setpoints of the instruments as a result of the modifica-tions for improved hydraulic coupling.

The licensee has addressed hydraulic coupling in the response to

• Design Criteria 1 and 7.

Because we have found the responses to Design Criteria 1 and 7 acceptable, and because the alarm.

rod block instrumentation is adequate, we find that the licensee's response to this criterion is acceptable.

4.2.4.10 Desian Criterion 10 Vent and drain line valves shall be provided to contain the scram discharge water with a single active failure and to minimize operational exposure.

Licensee Response Each drain and vent line is provided with two isolation valves in series and completely independent in operation.

The redundancy provided in the valve control air system by the DC solenoids provides acceptance to single failure criteria.

Additional information was provided by the lic2nsee in its responses to Safety Criterion 2.

Staff Evaluation An acceptable way of meeting this criterion is to provide two isolation valves in series for all SDV vent and IV drain valves.

The licensee stated that the drain and vent lines contain.two air-operated valves in series and discusses them further in its response to Safety Criterion 2.

'We have' reviewed the licensee's. response above and to Safety Criterien 2 and conclude that the requirements 1to this criterion have. been met.

4.2.5. Surveill ance - Cri teria

4. 2. 5.1 Surveillance Criterion 1 Vent and drain valves shall'be periodically tested.

A Surveillance and Test Procedure will cover the periodic ~ testing of. the vent and drain valves via the SOV-29 switch which.is located in the Main

' Control ~ Panel.

This test will record opening and closing times.

Valve closure will be verified to be less than 30 seconds.

Staff Evaluation

-i Existing Technical Specification surveillance requirements call for this type of test on a quarterly basis.

The licensee has proposed to' modify the1 Technical Specificat. ions to reflect the long-term modification; and include the criterion that the testing should -show valve closure in less than ~ 30 seconds.

Based on the above, we find the licensee's proposed TS regarding vent and drain valve testing to be acceptable.

4.2.5.2 Surveillance Criterion 2 Verifying and level. detection instrumentation shall be periodically tested in place.

Licensee Resconse Surveillance and Test Procedure No. F-ISP-66 (Scram Discharge.Vclume High Water Level Instrument Functional Test / Calibration) will be updated to require draining of the instrument via the IV connection following operability testing of each instrument.

In addition, operating procedures will be updated to require comparison of the Scram Discharge System drain rate

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with previous measurements subsequent to scram reset.

The TS-changes proposed by the licensee provide specifications for functional testing for the two RPS. circuits for High Water Level in the Scram Discharge Instrument Volume.

These changes prescribe monthly trip channel functional tests of RPS channel A level instruments' (float switches) and require that channel calibration be performed once per operating cycle using a water column.

Trip channel and alarm functional tests of RPS channel B level instruments (differential pressure-actuated switches) must be performed monthly, and channel calibration must be performed every three months using a standard pressure source.

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. t An acceptable method, to meet this criterion.is to require that the instru-ment chamber is drained after functional tests through the taps off the IV and:that post-scram, a comparison is made to' determine that the response.

time -(time to lower level) is consistent with previous measurements.

The licensee states that the instrument will be drained via the IV connec-tion to assure proper operation.

The lipensee has procedures for a post-scramcomparisonbetweentheresponsetigptopreviousmeasurements. The.

proposed functional ' tests are in accordance with the model TS provided by the staff. Therefore, we have reviewed the licensee's response to this criterion and find it acceptable.

4.2.5.3 ' Surveillance Criterion tio. 3-The operability of the entire system as an integrated whole shall be demonstrated periodically and during each operating cycle, by demonstrating scram. instrument ' response and valve function at pressure and temperature at approximately 50% control-rod density.

Licensee Response An fintegrated system test will be performed during start-up from the current refueling outage.

This test wil1 verit} operability of ~the entire system by demonstrating scram instrument volume response and valve function. This test will be performed at operating temperature and pressure with a control rod' density of approximately fifty percen,t.

In addition, the licensee has proposed surveillance requirements to demon-strate the operability of the integrated system each operating cycle.

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Staff Evaluation.

--A total integrited system test willJdemonstrate that the entire system retains its capability to monitor the accumulation of water-in the SDV and

- to scram the plant when required.

This test checks the spectrum of operation, that system components and instrumentation experience when going from normal l

. to scram conditions. Acceptable compliance is for the licensee to show reasonable. agreement with design analysis and any previous measurement.

The licensee has stated that once a cycle, instrument response and valve function will be demonstrated by scramming the plant from approximately 50%

or less ' control rod. density. The licensee may take credit for any scram

during the operating cycle that is initiated from those conditions. We have also' reviewed the licensee's response and find that the proposed :-

surveillance rcquirements meet the criterion and is therefore acceptable.

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Chance (2)

_ Air Dumo Header and Cortinuous SDV ';ateI Level Monitoring We have reviewed the licehsee's propossd changes to the FitzPatrick license

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that were transmitted in a letter dated July 7,1983.

The proposed changes would remove the conditions to't'he lic'ense' that were implemented by the ~.

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Commission's Order dated January 9,1981.

These conditions required, as an interim measure, for the licensee to provide an automatic scram from degraded air supply conditions until improved hydraulic coupling was incorporated ~

into the system.

As part of the short-term requirements, the Commission issued Orders fo.r1 Modification of License which required licensees to promptly implement certain -

actions to assure the safe operation of BWRs with inadequate SDV-to-IV hydrau-lic coupling.

One of the deficiencies identified in the Generic SER was a failure mode of the control air system, which could conceivably causeEan ;

inability to scram the control rods.

Sustained low pressure in the control air system could result in complete or partial opening of multiple scram outlet valves before the opening of scram inlet valves, thereby causing the SDV to fill rapidly, thus leaving a relatively short time for the operator to take' corrective action before scram capability is lost.

Therefore, as part of the short-term program to provide prompt added protec tion for credible degraded air conditions in BWR control air supply systems, the staff added license conditions that required an automatic system to :be~

operable by April 9,1981.

The automatic system would initiate controlirod insertion by rapidly dumping the control air system header if the air pressure decreased below a prescribed value.

The long-term solution to this problem.

is improved nydraulic coupling.

During the outage prior to operation in Cycle 6, the licensee will modify the SDV system to improve hydraulic coupling.

Hydraulic coupling will assure detection by level instrumentation and thereby >

provide a timely automatic scram, independent of the inleakage rate when the SDV headers fill.

Therefore, we have rev.iewed the licensee's request to remove the interim conditions from the license and find the licensee's proposed changes accept-able because long-term hydraul.ic coupling will be improved between the scram discharge headers and the instrument volume as discussed above.

The Commission had also issued, as an interim action, a Confirmatory Order on October 2,1980, pertaining to the addition of continuous monitoring instrumentation for SDV water level.

The Order confirmed licensee commitments made in accordance with IE Bulletin No. 80-17, " Failure of 76 of 105 Control Rods to Fully Insert During a Scram at a BWR," and its supplements..,The Bulletin and supplements were issued to provide adequate assurance that the licensee could maintain scram capability during operations until an ultimate resolution was achieved by changes in systems design and operating procedures.

That ultimate -resolution was subsequently identified and designated as the SDV long-term modification program.

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• o Because the-l'icensee has-attained this ultimate resolution through its implemencation of the long-term-SDV modifications evaluated and approved -

by us in Secticn A above, we find-that.the licensee's -request to remove

'the interim conditions imposed by the Commission's October 2,zl980 Confirmatory Order is also acceptable.

i; C. : Change (3) - Long Term Modifications We have reviewed the licensee's proposed changes to the FitzPatrick ' license

'that were transmitted in a -letter dated' July 7,1983.

The proposed changes.

would fulfill: the conditions to the license that were imposed'by the 3

Commission's Order dated June 24, 1983.

This Order confismed the licensee's-commitment to. install : permanent Scram-Discharge System =cdifications prior to operation in Cycle 6.

The modifications were to. conform to the criteria developed by the BWR Owners Subgroup and endorsed by our Generic Safety

~ Evaluation on the BWR Scram Discharge System, dated December 1,1980.

Based on cur review and acceptance of the licensee's modifications as described

.in Section' A of this Safety Evaluation, we find the licensee's modifications and cor.re.sponding proposed technical specifications to be in accordance with

- the staff's guidance.' Therefore, we find that the licensee has fulfilled the conditions imposed by the Commission's June 24,<1983 Order.

IV.

Environmental Considerations We have determined that the amendment'does not authorize a change in effluent types or total amounts nor an, increase in power level'and will not result in any 'significant environmental-impact.

Having'made thi's determir'ation, we

.have further c'oncluded that the amendment involves an action which:is insigni 6 ficant from thb ' standpoint.of environmental impact','and pursuant to 10 CFR SectionJ51.5(d)(4) that,an environmental impact statement, or fnegative declaration and-environmental impact appraisal need not be prepared in connection with the

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a issuance of the amendment.

V.

Conclusions We have concluded, based'on the considerations discus' sed above, that: (1) there is reasonable assurance that the health and safety. of the public will.

not be endangered by operation in the proposed manne~, and (2) such activities r

will be. conducted in compliance with the Commission's rigul~ations and the issuance.of this amendment will not be inimical to the common defense and security for to the health and safety of the public.

,s Dated: (August 26,.1983 Princihal Contributor:

J. Hegner 1

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