ML20080Q607

Assesses Operability of Purge & Vent Valves in Light of Concerns Outlined in Ser.Valves Will Be Opened to No More than 30 Degrees & Will Close from 30 Degrees Open Position in Event of DBA-LOCA

ML20080Q607
Person / Time
Site:	Oyster Creek
Issue date:	02/21/1984
From:	Fiedler P GENERAL PUBLIC UTILITIES CORP.
To:	Miraglia F Office of Nuclear Reactor Regulation
Shared Package
ML20080Q609	List: ML20080Q607 ML20080Q617
References
NUDOCS 8402240131
Download: ML20080Q607 (4)

Text

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GPU Nuclear Corporation Nuclear s'o=;388 Forked River, New Jersey 08731-0388 609 971-4000 Writer's Direct Dial Number:

February 21, 1984 Mr. Frank J. Miraglia, Assistant Director for Safety Assessment Division of Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Oyster Creek Nuclear Generating Station Docket No. 50-219 Purge and Vent Valves Your letter dated January 20, 1984 requested responses to two (2) statements pertaining to containment purge and vent valves.

We first response requested was an assessment of the operability of our purge and vent valves in light of the concerns outlined in your Safety Evaluation Report (SER). Our assessment remains as before, the valves in question will be opened to no more than 300 and will close from the 300 open position in the event of a DBA-IDCA.

The SER that was attached to your January 20, 1984 letter is factually incorrect. In section 3.0, Demonstration, the SER refers to two (2) GPUN letters that were sent to the NRC. These letters deal with two (2) different and separate approaches to the purge and vent questions. We January 23, 1979 letter refers to the purge and vent valves presently installed at Oyster Creek, while the January 13, 1983 letter addressed the new, qualified, purge and vent valves that are to be installed during the Cycle 11 refueling outage. Because of this confusion, the evaluation and summary sections of the SER state incorrect conclusions.

Our engineering evaluation, showing that the presently installed purge and vent valves can close against full dynamic blowdown loads from the 300 position, was subnitted to the NRC by a letter dated August 27, 1981. A copy of the evaluation, along with the submittal letter, is attached. Our letter of January 13, 1983 dealt with the new valves that are to be installed during the Cycle 11 outage. That letter stated that a description of the valve qualification program utilized would be provided after the valves are installed. Given the above information, GPUNC believes that our previous assessment of the operability of our purge and vent valves remains valid.

8402240131 840221 d PDR ADOCK 05000219 D P PDR 1

GPU Nuclear Corporahon is a subsidiary of the General Pubhc Utikties Corporahon i

In response to your_second request, GPUNC sees no reason to maintain the purge _and vent valves sealed closed and to verify them to be closed every-31 days. S e requirements quoted in your letter, which were extracted fran SRP section 6.2.4, are inpractical for any plant with an inerted containment to meet. Mark I inerted containment plants must vent and purge during startup and prior to shutdowns. Oyster Creek's Technical Specifications also require that drywell-suppression chamber differential pressure must be maintained within the acceptable operating range except for a maximum four (4) hour pericd during which the required operability testing of the drywell-pressure suppression chamber vacuum breakers is conducted. ' Be four (4) hour maximum could not be met

without using the larger purge and vent valves. As the Technical Specifications ~also mandate that all of the drywell-pressure suppression chamber vacuum breakers be tested each month, this would lead to reducing the differential pressure more than once a month to complete the vacuum breaker tests.

In addition to the above requirements, V-26-16 and V-26-18 are our reactor building to suppression enamber vacuum breaker valves. Your letter incorrect.ly asaumes that the interim requirement to limit the opening of the vent and purge valves to no more than 300, and the final replacement with qualified valves applies to those valves. Bis is an incorrect assunption. The safety function of the vacuum breaker valves is to open and equalize the pressure between th suppression chamber and reactor building so that the containment exterr.a1 design pressure limits

. are not exceeded. Se system'is designed to initiate automatically only when reactor building pressure exceeds the suppression chamber pressure by 0.5 paid. Se operability requirements are identified in our Technical Specifications, section 3.5.A.4 on page 3.5-2, and a copy of the' applicable page is attached for your review.

To sunnarize, we believe maintaining our purge and vent valves closed in accordance with SRP section 6.2.4.II.6.f is inappropriate for any Mark I'inerted containment plant such as Cyster Creek. W e new, qualified valves are to be installed during our Cycle 11 refueling outage. In the interim, we believe that acceptable'information has been submitted which demonstrates our present purge and vent valves, which are limited to 300 opening, will close _in the event of a DBA-IDCA.

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Should you have any other questions, please contact me or Mr. Michael Laggart of my staff at (609)971-4643 or, if you deem it necessary, we would be glad to meet with you to fully discuss the issues.

Very truly yours,

-f Peter B. Fiedler Vice President and Director Oyster Creek PBF:RPJ: dam Attachment sworn to and sucscribed before me this o7/ day of February 1984.

cc: Mr. Dennis M. Crutchfield, Chief g* g Operating Reactors Branch #5 g/ N, Division of Licensing " (//

U.S. Nuclear Regulatory Commission Washington, DC 20555 MICHAEL LACCART NOTARY PUBUC OF Nty jggggy Dr. '1homas E. Murley, Administrator "' b"*'m bres De:emtu 31. H85 Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731

- 3.5-2 s

l. . ,Rese:or 3cildine :: Suoereszien Chamber Yace= 5:eaker S este:

a. Excep: as specified in Specificatien 3.5.A.4.5 bel:g,

ve reactor building :o suppressica cha=ler vacuu.:  ;

breakers in each line shall be operable a: all :i=es when pri=ary cen:ainment integrity is re:iuired. la set poin: of the dif ferential pressure 1:s::u=enta:ien which ac:uates :he air-cperated vacue= breakers shall

o: exceed 0.5 psid. The vacuu: breakers shall =cre frem clesed :e fully open when subjected := a force equivalent of no: greater than 0.5 psid a :1:s en the racuu: b:eaker disc.

b. 7::= :he ti=e that ene of the reactor buildi:g :o suppressien :ha bar vacuu: breakers is =ade c fou:d

o be in perable, the vacuu: hreaker shC1 be isched

lesed a:d rea:::: cpera:ic: is per=issiile enly du-i=g

-he succeedi:3 seven days unless such va::== breaker is ade operable scener, provided tha: :he ;::cedure does ze: vi la:e ;;i=ary centain=en: integri:7

c. If the limits =f Specification 3.5. A.3.a are ex: ended, reac:or shu:ic-m shall be iniziated and the reae:c:

shall be in a cold shutdown conditien vi:hin 1."- he::s.

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%k Pressure Sueeressi:n chamber - D, .: ell vaeue- 3:eakers

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a. nen pri=ary c=n:ainment is required, all su;pressi =

cha=ber - d:f. ell vacuum breakers shall be operable except during :esting and as stated in Specifiest:.:=

3.5.A.4.b and : belev. Suppressics cha:ber - dr- eell vacuu: breakers shall be considered operable if:

(1) The valve is demens::a:ed to epe f::= clcsed :c

- fully c;e= with the applied force a: all .al e positic:s not exceeding that eouiva*.e=: cc 0.f psi ac:ing on the suppressica cha=her face of -J:e valve disk. .

(2) ~he valte disk vill clcse by gravi:7 to vi:hi:

not grea:e: than 0.10 inch of . a=y p:i== o.. the seal se:f ace of :he disk when released after being c;ened by remote or =anual cea=s.

(2) ~~.e pcsi:ica alar = sys:e= vill annu cia:e in :he c:n:::1 ::en if :he valve is cpe.n :::e :han ~.10 inch a: any poi.: along the seal surfcce =f :le disk.

Inentment No. ,'d, K, f

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r Madison Avenue at Punch Bowl Roac Mornstown. New Jersey 07960 (201)455-8200 Augusc 27, 1981 Director, Nuclear Reactor Regulation United States Nuclear Regulatory Commission

- Washington, DC 20535

Dear Sir:

Su b,'ect: OvsTer Creek Nuclear Generating Station Docket No. 50-219 Cycle 10 Refueling / Maintenance Outage The purpcse of this letter is to inform you of our intention to reschedule our Cycle 10 Refueling / Maintenance Outage from November 30, 1931 until tre t*me period of February or March 1982 and to request approval of revised dates for speci f ic regult, tory requirements and com.it ents.

There are several factors which necessitated this change in schedule. Tne scope of the Cycle 10 Refueling / Maintenance Outage is significantly larger than any previous Oyster Creek Outage. The large outage scope has resulted in the need for er extended time period, in which to better' plan, prepare for, and coordiiate all the activities associated w!th the Cycle 10 re:oad. One of tt'e major outage projects, the Core Spray Sparger replacement, involves an axtensive amount of work inside the reactor vessel. Some of the extended planning and coordination ef fort involves training on a reactor vessel mockup. This will prepare the work crews to ef ficiently do the sparger replacement and thereby significally reduce man-hour exposure. Also, a shutdown on November 30,19e1 wilI cause unnecessary economic hardshi'p for the Jersey Centra: Pcwer & Light Company CJCP&L) and its customers since TMI Unit 1 is not expected to achieve full power until after the November 30

- - date. Therefore, JCP&L would be forced to purchase electrical power at -

the PJM interchange rate.

in addition to the general problems associated with properly preparing fer the cutage, there are neveral key pieces of equipment required for 9ccifications to the plant which will not be delivered until after the November 30 date.

1. Since a full core offlo9d is required to install the ca- core sprav spargers, an upgrade to the fuel pool cooling svs'em is being engineered. The motor starters required for this project .ill not be Yu 7 / Y w- -

Jersey Central Power & Ugnt Company s a Member of the General Pubhc Ut& ties Systern

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• d'elivered until February 15, 1982. -

2. All of the equipment requiced _for upgrading the Reactor Protection System (RPS) Instrumentation will not be delivered until approximately April 1982.

3. We are still in the process of designi'ng the modifications to the Scram Discharge Volume (SDV) and do not expect that this project will be ready to support a November 30, 1981 outage.

Due to this change in outage schedule, we are requesting a change in the commitment dates of several regulatory required modifications.

1. By NRC Order dated January 13, 1981, we are required to have completed all major Mark l Containment nodifications by December 30, 1981. We request that this Order be revised to require that these modifications be completed prior to startup from Cycle 10 reload refueling / maintenance outage. We feel that this delay will not pose an undue threat to public health and safety since the Oyster Creek facility has completed alI of the requirements of the short-term Mark l Program and some of the modifications of the long-term program.

2. By. letter dated July 31, 1980, we committed to replace,. by December 1, 1981 the Containment Ventilation and ? urge Valves with ."quallfled" valves. We request that this commitment be revised to require these modifications prior to startup from our Cycle 10 reload refueling / maintenance outage. We feeI this delay is justifled since we are presently folicwing the NRCs interim guidelines for these valves.

-These are normally closed valves; and when opened they are mechanically restricted from opening more than 30'. In addition, attached is our '

engineering evaluation showing that these valves can close against f ulI dynamic blowdown loads from the 30' position.

3. We have committed to complete the following NUREG 0737 Items by January 1, 1982:

1 TEM SHORT TITLE I l .E .4.1 Dedicated Hydrogen Penetrations l l .F.h Accident Monitors ll.K.3.14 1 solation Condenser isolation Signals il.K.2.19 Recirculation loop Interlock II.K.3.25 Recirculation Pump Seals 11.B.2.2 Plant Shielding iI.B.3.2 Post-Accident Sampiing We request th.i the com.nitment date for these items be revised

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to.. require that these items be completed prior to startup from our Cycle 10 reload refueling / maintenance outage.

We feel that the celay of these items" is justified since they all are longer-term TMl Lessons Learned items that can be planned and

. scheduled to coincide with scheculed plant outages. Also, all of the short-term Lessons Learned p l. ant changes have been implemented at the Oyster Creek plant.

NUREG 0737, item I I .E.4.2, Containment isolation, requires that all vent and purge valves be modified to isolate on a high radiation signal. It was our original Intention to use the Containment High Radiation Signal for this parpose and have this completed by the NUREG reguired date of January 1, 1982. After carefully examining this

• requirement, we have concludec that it would not be an appropriate modi fication to the Oyster Creek f acility. This determination is based upon the f act inat the Purge anc Vent Valves at OysterCreek are normally closed during power operation and in the event they were open, they would. Isolate en the cIverse parameters of either low-low reactr water - -

level or high crywell pressure.

It should be noted that we have also requested relief from the United States Environmen'tal Protection agency National Pollutant Discharge Elimination System (NPDES) permit and the New Jersey Department of Environmental Protection NJPDES permits. These p'ermits prohibit scheduled plant shutdowns curing the months of December, January, February, or March. Since several dif ferent agencies are involved, the scheduling of the ref ueling outage is contingent upon

' receipt of relief from all egencies. ,

Your expeditious review of this request would be appreciated.

If you have any further questions, please contact Mr. James Knubei (201 299-2264) of my staff.

Very truly yours, j  :< ('

- - Philip R lark Vice President-Nuclear Jersey Central Power -& Light Company

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