HL-4433, Forwards Revs to Relief Requests RR-V-17,RR-V-19,RR-V-20, RR-V-32,RR-V-40 & RR-V-41,providing Addl Info as Discussed in 930901 Telcon Re Second 10-yr Insp Interval IST Program

Forwards Revs to Relief Requests RR-V-17,RR-V-19,RR-V-20, RR-V-32,RR-V-40 & RR-V-41,providing Addl Info as Discussed in 930901 Telcon Re Second 10-yr Insp Interval IST Program

ML20059B407
Person / Time
Site:	Hatch
Issue date:	12/21/1993
From:	Beckham J GEORGIA POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
HL-4433, TAC-M59202, TAC-M59203, TAC-M83192, TAC-M83193, NUDOCS 9401040118
Download: ML20059B407 (16)

Text

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Goorgia Power Company

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• 40 trwerrtsss Contor Parkway Post Office Box 1295 ' ,

Strmingham, Alabama 3s201 Telephone 205 877 7279 L

J. T. Beckham, Jr. Georgia Power Vice Presdent - Nuclear Hatch Project the soutoem electic sptem December 21, 1993 Docket Nos. 50-321 HL-4433 50-366 TAC Nos. M59202, M83192 M59203, M83193 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Edwin I. Hatch Nuclear Plant Second Ten Year Inspection Interval IST Program Safety Evaluation Response Gentlemen:

By letter dated November 17,1992, Georgia Power Company (GPC) provided responses to the 11 remaining anomalies identified in the Nuclear Regulatory Commission (NRC) stafl"s safety evaluation transmitted to GPC by letter dated December 10,1991. These anomalies are currently being evaluated by the NRC staff.

On September 1,1993, a conference call was held between GPC representatives and the appropriate Nuclear Reactor Regulation (NRR) staff to discuss relief requests RR-V-17, RR-V-19, RR-V-20, RR-V-32, RR-V-40, and RR-V-41. The enclosure to this letter provides revisions to these relief requests which provide additional information as discussed in the conference call.

Should you have any questions in this regard, please call this oflice.

Sincerely,

/ y/

1 T. Beckham, Jr. /

- JKB/cr Enclosure 940104o13s 931221 e dj I hDR. ADOCK 050003g3 f

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U.S. ' Nuclear Regulatory Commission Page Two December 21, 1993 cc: Georgia Power Company Mr. H. L. Sumner, Nuclear Plant General Manager .

NORMS US. Nuclear Regulatory Commission. Washington. D.C, Mr. K. Jabbour, Licensing Project Manager - Hatch U.S. Nuclear]Legulatory Commission. Region 11 Mr. S. D. Ebneter, Regional Administrator Mr. L. D. Wert, Senior Resident Inspector - Hatch i

-004433 j

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Enclosure Edwin I. Hatch Nuclear Plant Second Ten Year Inspection Interval .

IST ProgLam Safety Evaluation Respong - ,

d The enclosure provides revisions to six relief requests previously submitted by letter dated.

November 17,1992.

1. Relief Request RR-V-17 Relief Request RR-V-17 requested relief from exercising the Unit 2 residual heat -

removal injection check valves on a quarterly basis to verify forward flow operability.

Relief Request RR-V-17 was revised and submitted on November 17,1992 to provide justification for not partial-stroke exercising both valves during each cold shutdown.

The revision also provided for a full-stroke exercise of both valves each refueling.. L outage. During the conference call, the NRR staff questioned _ how GPC is determining that the valves are fully exercised during shutdown cooling operations - '

every refueling outage.

Relief Request RR-V-17 has been revised to provide additional information.  :

Verification will be accomplished by an external visual determination of the disk position. The valve design incorporates a two piece hinge pin 'which allows for a visual determination of hinge pin rotation. A copy of the revised relief request is attached to the enclosure. ,

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2. Relief Request RR-V-19 Relief Request RR-V-19 has been revised to clarify that the requested relief is applicable only to the Unit 2 high pressure coolant injection system pump room cooler .

outlet check valves. ~ The relief request submitted on- November .17, .1992 was  :

incorrect in that the core spray and residual heat removal pump room coolers were ,

included.' A copy of the revised relief request is attached to the enclosure.

' 3. Relief Request RR-V-20  ;

Relief Request RR-V-20 originally requested relief from_ exercising and switch-to-light  ;

stroke timing several plant sewice water power operated valves and proposed to verify ' -.

proper operation by assigning a maximum stroke time and measuring stroke times by ?  ?

direct observation. Relief Request . RR-V-20 was revised - and submitted on November 17,1992 such that the valves will be stroke timed by observing actual stem movement. During the conference call, the NRR staff questioned the applicability of -

data trending.

i HL-4433 E-1 .l

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Enclosure Second Ten Year Inspection Interval IST Program Safety Evaluation Response Relief Request RR-V-20 has been revised to include comparative trending of stroke time data to monitor for valve degradation. The relief request has also been revised to clarify the actual code requirement for which reliefis being requested and to provide additional information relative to the accuracy of stroke time measurements by.

observation of valve stem movement. A copy of the revised relief request is attached -

to the enclosure.

4. Relief Requ_ests RR-V-32 and RR-V-40 Relief Requests RR-V-32 and RR-V-40 requested relief from measuring the stroke-time of the traversing incore probe (TIP) purge supply valves. The relief requests were revised and submitted on November 17,1992 to propose trending oflocal leak rate testing data to monitor for valve degradation. During the conference call, the NRR staff questioned the adequacy of the proposed method to identify valve degradation.

Relief Requests RR-V-32 and RR-V-40 have been revised to provide additionai' justification supporting the proposed alternative testing. Plant design did not require or incorporate remote' indicating lights for the TIP purge supply valves. The subject valves perform a safety function for containment isolation only, and the FSAR analysis indicates that the associated I;ne is of such a size that even if the valve did not close and the line ruptured, the plant would still comply'with offsite release limits.

Testing to monitor.for degradation does not add any _ additional confidence level or margin of safety. The subject valves are leakrate tested each refueling ~o utage which verifies their ability to close and provide containmen' t isolation. Testing to monitor degradation will require a system modification or the use of specialized testing equipment, .either of which imposes additional burden and hardship on the utility .

without a commensurate confirmation or increase in the level of safety afforded the i public. The proposed alternative testing identified in Relief Requests RR-V-32 and RR-V-40 is appropriate to confirm the subject valves' operability, Copics of the revised relief reguests are attached to the enclosure.

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Enclosure Second Ten Year Inspection Interval i IST Program Safety Evaluation Response  ;

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5. . ReliefReauest RR-V-41 Relief Request RR-V-41 requested relief from full flow exercising the diesel generator. ,

service water outlet check valves quarterly and proposed to perform exercising in . ,

conjunction with diesel generator tests. The relief request was revised and submitted on November '17,1992 to provide the approximate power levels at which the diesels -

are tested and to include a proposal to disassemble, manually exercise, and visually ,

inspect one valve every third refueling outage on a rotating basis. During Lthe ' j conference call, the NRR staff questioned the stated interval and inquired into the  !

service conditions and maintenance history applicable to these valves. l Relief Request RR-V-41 has been revised to provide additional justification for the ,

disassembly and inspection frequency and to clarify the justification for the proposed  ;

alternative testing. A copy of the revised relief request is attached to the enclosure. ,

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RELIEF REQUEST RR-V-17 SYSTEM: RHR VALVE (S): 2 Ell-F050A,B CATEGORY: AC CLASS: 1 FUNCTION: LPCI and Pressure Isolation TEST REQUIREMENT: Verify forward flow operability quarterly or at cold shutdown per IWV-3520.

BASIS FOR RELIEF: The plant and RHR system configuration does not provide for.

full or partial flow exercising during normal operation.  ;

LPCI injection during normal operation is impossible because reactor pressure is significantly greater than LPCI injection pressure. Therefore, full or partial exercising with flow quarterly is impossible.

During the shutdown cooling mode of RHR operation, the normal flow rate is between 7700 and 8200 gpm. At 7700 gpm the flow velocity is approximately 14 fps. Valve vendor information  ;

indicates that a flow velocity of a 10 fps is sufficient to fully open the valve disk if.the valve is in good operating condition. Therefore, normal shutdown cooling flow rates are <

sufficient to fully open the disk of a valve .in good -

operating condition.

Valve design incorporates a two piece (outside hollow cylinder and inside solid cylinder) hinge pin because the valve was initially provided with an operator which was used. t to minimally exercise the valve disk. The operator.is no..

longer utilized for disk exercising, but the'two piece hinge "

pin allows for external visual determination of the disk  :

position by observing the inside hinge pin position.

It is normal plant practice to utilize only one loop of RHR in shutdown cooling for any unscheduled shutdown due to the extra efforts involved in system alignment, flushing, pipe warm-up and swapping of loops. To require both loops of RHR shutdown cooling to be. placed in operation during an -

unplanned shutdown for the sole purpose of exercising each -

check valve seems unwarranted. Therefore, exercising both~

valves at each shutdown'is impractical.

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RR-V-17 (cont.)

ALTERNATE TESTING: At least one of these check valves receives shutdown cooling flow (7700 - 8200 gpm), therefore is at least partially exercised, each cold shutdown. The loop of RHR shutdown cooling placed into service will be alternated for each unplanned shutdown. Therefore, a different valve will be at '

least partially exercised each time shutdown cooling is utilized.

During each refueling outage, both loops of RHR shutdown cooling are utilized in support of normal shutdown and fuel Therefore both valves are exercised handling activities.

during each refueling outage.

In conjunction with RHR shutdown cooling operation each refueling outage, external visual observation of rotation of the' inside hinge pin will be utilized to confirm that the valve disk is fully open. Scribe marks, angular measurements '

or some other positive means will be.used to ensure that the flow actually moves the valve disk to the full open position.

If visual observation does not confirm that the flow has '

fully exercised the valve disk, then appropriate additional actions will be taken (e.g. mechanically exercising the valve perIWV-3522(b) disassemble, exercise and visually inspect, etc.).

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RELIEF REQUEST' RR-V-19 SYSTEM: P' ant Service Water-VALVE (T) co24A&B CATEGUM: t, CLASS: 3 FUNCTION: Provide cooling water flow to HPCI pump' room coolers l!

TEST REQUIREMENT: Verify forward flow operability quarterly or at cold shutdown ,

per IWV-3520.

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BASIS FOR RELIEF: Dur_ing quarterly testing of the HPCI pumps, the associated. l room coolers are placed . in operation,J thereby exercising these valves. However, system _designLdoes not provide for positive verification (flow instrumentation) of.the flow rate -

through each valve. Therefore, . confirmation of full flow exercising quarterly or at cold shutdown:is impossible. .

ALTERNATE TESTING: GPC has implemented a Plant Service Water System Performance Monitoring Program which performs' periodic flow measurements at various' locations throughout the systemi'tol detect potential flow'or component degradation. These measurements are performed prior to each scheduled- refueling ontage in-order that any required -corrective measures. 'can be implemented during the -subsequent' outage. LTemporary ultrasonic flow measuring _ instrument's are utilized to obtain -

the required system flow rates and the architect engineer has provided .the design basis acceptance criteria for each -

location included in the program.

The- ECCS room coolers .-are considered . important pieces L of equipment, and thus Lservice water flow to-- and from each cooler is included in the services water performance-monitoring nrogram.. '

The GPC Service Water Performance Monitoring Program will, be.

utilized prior to each refueling outage to' confirm that these check valves are capable of opening.sufficiently to perform  !

their safety related function. -Trending of the associated  ;

flow measurements will provide data' which is potential.ly; indicative of' check valve degradation.

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RR-V-19 (cont.) l Partial exercising of each check valve is confirmed during quarterly testing of the associated ECCS room coolers. .l Temperature indicators are provided in the system piping H which will provide some. assurance that the check valves are 1 not stuck in the closed position. -  ;

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RELIEF REQUEST RR-V-20 SYSTEM: - Plant Service Water VALVE (S): IP41-F035A&B, IP41-F036A&B, IP41-F037A-D,-IP41-F039A&B, IP41-F340' 2P41-F035A&B, 2P41-F036A&B, 2P41-F037A-D, 2P41-F039A&B, 2P41-F339A&B  :

CATEGORY: B  :

CLASS: 3 FUNCTION: Equipment Cooling Water Supply Valves TEST REQUIREMENT: IWV-3413(a) requires stroke timing of power operated valves from initiation of- actuating signal to the end of. the i actuating cycle. This is commonly referred to as " switch-to- l-light" timing.

BASIS FOR RELIEF: These valves are normally closed, fail open air operated i

. valves which have a safety function _to .open and provide.

cooling water flow to .the associated safety related- -i equipment. System design did not provide indicating lights .

or direct valve control switches. Therefore, " switch-to-  !

light" timing is not possible.

The valves receive an open signal upon initiation of the ,

associated equipment and a close signal upon termination of operation of the associated equipment. .Therefore,:  !

measurement of valve stroke . time can only be performed by i observation of the actual valve stem movement when the-associated equipment is placed into service. -:

These valves have allowable stroke times ranging from 5; :i seconds for the smallest valves to 30 seconds for the largest-valves. IWV-3413(b) requires stroke times to be measured to the nearest second for stroke times of 10 seconds or less and -  !

within 10% of the specified limiting. stroke time for times >

greater than 10 seconds. . Review of past stroke time data and interviews with operations personnel directly involved'with the testing,-indicate-that.the requirements of.IWV-3413(b) are achievable utilizing a digital stop watch and observing-actual valve stem movement from the closed to open. position.  ;

ALTERNATE TESTING: Each valve _ wil.1 be. stroke timed by observing actual valve .

stem movement. Stroke time will be considered to be the time  :

from start to stop of valve stem movement. The requirements of.IWV-3417(a) _will be applied to monitor valve degradation.

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RELIEF REQUEST RR-V-32 SYSTEM: Traversing Incore Probe (TIP)

VALVE: 2C51-F3012 CATEGORY: A CLASS: 2 FUNCTION: Containment Isolation TEST REQUIREMENT: IWV-3413 requires power operated valves be stroke timed quarterly and IVV-3417(b) requires comparison testing.

BASIS FOR RELIEF: The safety . "' of this valve is CLOSED to provide containment isolation which is initiated by a LOCA signal and results in isolation of TIP purge and the TIP probes.

Neither the Technical Specifications or the FSAR have any specific requirements for isolation stroke time for this valve.

This is a normally open, nonmally energized solenoid operated valve which strokes in milliseconds. The valve was not provided with remote indicating lights and its design does not provide for observation of actual stem movement (stem is fully enclosed).

A simple check valve is located upstream of this solenoid-valve which provides. outboard-containment isolation of the penetration. Nitrogen purge is at a steady flow anc. p essure which does not impose any harsh operating conditions on this check valve. Therefore, this upstream check valve provides additional assurance for isolation of the associated penetration.

The purge line is small (3/8") and the FSAR evaluation indicates that even in the event of a TIP dry tube failure and non-isolation of the purge line, the radioactive release .

would remain within-the allowable limits.

Since this valve strokes in milliseconds, it is classified as a rapid acting valve per GL 89-04, Position 6. Therefore,. )

if indicating lights or valve stem movement were observable, i comparison time testing of valves with stroke times of less than or equal to 2 seconds is not required.

Industry history' indicates that solenoid valves either j operate properly or not at all. It has not been established that stroke time testing of solenoid valves provides data ,

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applicable for evaluation of; degradation. The application: y of some type of electronic monitoring would.be on a trial and 1 error basis - since. .no such ' equipment has : been proven to - .j provide useful: test data to date. Considering' the safety .;

function of the- valve (containment oisolation only) and:the'

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redundancy of this function'provided by a simple check valve,-  :!

testing to monitor degradation will not provide a significant increase in assurance _that the. valve is capable of performing. .

its intended function. -i ALTERNATE TESTING: This valve will be exercised closed quarterly. and - e observation that nitrogen flow in the associated tubing'has stopped will be utilized as confirmation 'that ~ the' valve is in the safety related closed position. -i This valve is local leak rate tested (LLRT).at' each refueling - l outage in accordance with 10 CFR-. 50, Appendix J. . LLRT i

- provides assurance that the valve is in the closed position  ;

and thus is capable ~of'.providing its safety function of-containment isolation.- ,

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RELIEF REQUEST RR-V-40 SYSTEM: Traversing Incore Probe (TIP) ,

VALVE: IC51-F3012 CATEGORY: A CLASS: 2 FUNCTION: Containment Isolation TEST REQUIREMENT: IWV-3413 requires power operated valves be stroke timed

. quarterly and IWV-3417(b) requires comparison testing.

BASIS FOR RELIEF: The safety position of this valve is CLOSED to provide , .;

containment isolation which is initiated by a LOCA signal and -

results in isolation of TIP purge and the TIP probes.  !

Neither the Technical Specifications or the FSAR have any specific requirements for isolation stroke time for this -

valve.

This is a normally open, normally energized solenoid operated valve which strokes in milliseconds. The valve was not.- i provided with remote indicating lights and its design does i not provide for observation of actual stem movement.

l A simple check valve is located upstream of this solenoid  !

valve which provides outboard containment isolation of the )

penetration. Nitrogen purge is at a steady flow and pressure l which does not impose any harsh operating conditions on this' i check valve. Therefore, additional assurance is provided for l isolation of the associated penetration. 1 The purge line is small (3/8") and the FSAR evaluation -l indicates that even in the event of a TIP dry tube failure - i and non-isolation of the purge line, the radioactive release  ;

would remain within the allowable limits. i Since this valve strokes in milliseconds, it is classified as a rapid acting valve per GL 89-04, Position 6. Therefore, if indicating lights or valve stem movement were observable, comparison time testing of valves with stroke times of less than or equal to 2 seconds is'not required.

Industry history indicates that'. solenoid valves either.

operate properly or not at all. It has not been established that stroke time testing of solenoid valves provides data applicable for evaluation of degradation. The application of some type of electronic monitoring would be on a trial and Page 1 of 2

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i error.. basis since no suchl equipment has t,een proven ~ to provide useful test data to:date.' Considering the. safetyf ,-

o function of the .. valve (containment - isolation) Jand. the 'j redundancy of thh function provided by a simple check valve,: ,

, testing to monitor degradation will_ not provide a significant increase in assurance thatithe' valve is capable ~of performing its. intended-function.

j ALTERNATE TESTING: The valve will'be exercised closed quarterly, and observation of a decrease in nitrogen pressure in-the. associated tubing: .

will be utilized as confirmation that the valve 'is .in ~ the. >

safety related' closed position.

This valve is local leak rate' tested (LLRT) at each refueling. j outage in accordance' with .10 CFR 50, .. Appendix -J. Ly3T . i provides assurance that the' valve is.in the closed posit 3pn and thus is capable of providing. its safety., function of. i containment' isolation, j l

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RELIEF REQUEST RR-V-41 SYSTEM: Plant Service Water VALVE (S): IP41-F552A&C CATEGORY: C CLASS: 3 FUNCTION: Diesel Generator Cooling Water Discharge Line Check Valves TEST REQUIREMENT: Verify forward flow operability quarterly per IWV-3522(b).

BASIS FOR RELIEF: These normally open check valves are located in the cooling water discharge lines from diesel generators lA and IC.

There are no system design provisions to measure cooling water flow and thus verify forward flow operability.

Each diesel generator is operated for a. minimum of one hour at 1710 - 2000 kW (approx. 60 percent of continuous rated load) during testing once each month. Partial forward flow operability is verified during this test by monitoring diesel generator oil and jacket cooling water temperatures. If sufficient cooling water flow was not provided to the diesel generator, elevated oil and jacket cooling water temperatures would be evident.

Each diesel generator is also operated for a minimum of one hour at 2250 - 2400 kW (approx. 80 percent of continuous rated load) semi-annually. Partial flow operability is again verified during this test by monitoring diesel generator oil and jacket cooling water temperatures.

During each refueling outage (at least once per 18 months).

each diesel generator is operated for a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

During the first two hours of this test, the diesel is loaded to 2: 3000 kW (approx. 105. percent of continuous rated load) and during the remaining 22 hours2.546296e-4 days <br />0.00611 hours <br />3.637566e-5 weeks <br />8.371e-6 months <br /> of this test, the diesel is loaded to 2775 - 2825 kW (approx. 90 percent of continuous ratedload). Diesel generator' oil and jacket cooling water temperatures-are monitored during this test to ensure that sufficient cooling water is provided.

Acceptable operation of the diesel generators during the monthly and semi-annual tests verifies .that the valves are not stuck in the closed position. Acceptable operation of the diesel generators during each refueling outage test Page 1 of 2

RR-V-41 (cont.)

verifies that the check valves have opened sufficiently to perform their design function. The diesel . generator oil and-Jacket cooling water temperatures for each test are trended to ensure no significant changes occur from test to test. .

The Architect Engineer-(AE) performed an evaluation of these .,

valves associated with INPO SOER 86-03 in 1987. This evaluation considered valve type, operating conditions and environment, and past valve maintenance history. The AE recommended periodic disassembly and inspection of the valve internals with at least one of the two valves being inspected every third refueling outage. The AE also recommended that the frequency of inspection .be adjusted depending on inspection results.

ALTERNATE TESTING: Existing monthly and semi-annual diesel surveillance testing will be utilized to prove at least partial check valve exercising. The existing refueling outage frequency diesel testing will be utilized to confirm that the valves will open sufficiently to perform their design safety function.

Additionally, at least one of the two valves will be disassembled, manually exercised and visually inspected every refueling outage on a rotating frequency. ' This disassembly frequency should be adequate to detect any valve degradation in sufficient time to take corrective action and prevent the.

valve from being unable to performing ~its safety function.

Inspection results will be reviewed, and the disassembly frequency will be adjusted if warranted. l-The valves are flanged into the system piping and are completely removed when inspected. The valve is visually inspected and manually full stroke exercised prior to being reinstalled in the pipe line. The valve disassembly is performed prior to the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> diesel surveillance test, thus the safety function of the valve is confirmed after reassembly by monitoring diesel generator cooling during testing. This diesel testing confirms at least partial valve exercising after reinstallation in the system.

Existing diesel generator surveillance testing in conjunction with the periodic disassembly and inspection should confirm the capability of the valves to perform their intended safety function and should identify any degradation concerns prior to the valves becoming inoperable.

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