ML20038B962

Forwards Responses to TMI Action Items II.D.1 (Relief & Safety valves),II.K.3.24 (Space cooling),II.K.3.28 (Accumulator on Automatic Depressurization Sys Valves) & II.K.2.44 (Anticipated Transients W/Single Failure)

ML20038B962
Person / Time
Site:	Pilgrim
Issue date:	12/03/1981
From:	Morisi A BOSTON EDISON CO.
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
RTR-NUREG-0737, RTR-NUREG-737, TASK-2.D.1, TASK-2.K.3.24, TASK-2.K.3.28, TASK-2.K.3.44, TASK-TM 81-276, NUDOCS 8112090366
Download: ML20038B962 (5)

Text

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BOSTON EDISON C O M PANY GENERAL OFrtCEs 500 BovLaToM ETREET Boston,MassacNum o A. V. M O R151 MANAGER ga g NUCLEAR OPERATIONS SUPPORT DEPARTMENT p , .

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• 3 December 3, 1981

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Q. BECo. Ltr. #81- 276

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Mr. Darrell G. Eisenhut, Director .

Division of Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D. C. 20555 License No. DPR-35 Docket No. 50-293 NUREG 0737 Items II .D.1, II .K.3.24, II .K.3.28, and II .K.3.44

Dear Sir:

Attached, please find Boston Edison Company's response to the subject NUREG items. Should you have any questions or concerns as a result of your review, please do not hesitate to contact us.

Very truly yours, N A h Y $0116l Attachments:

Response to NUREG 0737 item II.D.1 II.K.3.24 II.K.3.28 II.K.3.44 nfb61 e11209'0366 e11203 )

PDR ADOCK 05000293 '

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II.D.1 Performance Testing of Boiling-Water Reactor and

, Pressurized-Water Reactor Relief and Safety Valves.

• Reference 1) Letter from T. Dente (BWR Owners' Group) to D. G.

Eisenhut (NRC), " Transmittal of Valve Operability Test Report from Generic BWR Safety / Relief Valve

. (SRV) Test Program"

2) BEco. Letter #81-199, dated August 20. 1981 Boston Edison Company has reviewed the final test results contained in NEDE-24988-P, " Analysis of Generic SWR Safety / Relief Valve Operability Test Results" (Reference (1)), which we believe adequately demonstrates the operational adequacy of the S/RV's, S/RV discharge piping and supports for Pilgrim Nuclear Power Station for the conditions defined in item II.D.1.

Pilgrim Station employs the Target Rock 2 stage type of S/RV. The applicability of the generic test results has already been demon-strated via Reference 2.

The submittal of NEDE-24988-P and this letter satisfies the October 1,1981 and January 1,1982 submittal requirements of item II.D.1 and completes Boston Edison's efforts on this item.

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II.K.3.24 Confirm Adequacy of Space Cooling for High-Pressure Coolant Injection and Reactor Core Isolation Cooling Systems.

The space cooling for HPCI and RCIC-is derived from pairs of equipment area cooling (EAC) components V-AC-201 A and B and V-AC-202 A and B, respectively. The safety objective of the EAC requires the ability to maintain the local environment of the electrical components of the core standby cooling systems at temperatures within their maximum allowable operating limits. HPCI and RCIC unit coolers are powered from motor control centers (MCC) B18 and B17. Upon loss of offsite 4 power, the MCC's are powered by the diesel generators, which are able

, . to sup91y power for more than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.

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We believe this information adequately addresses the concern of this-NUREG item and plan no further action in this area.

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II.K.3.28 Verify Qualification of Accumulators on Automatic Depressurization System Valves The safety objective of the nuclear system pressure relief system is to prevent overpressurization of the nuclear system. In addition, the automatic depressurization feature reduces the nuclear system pressure so that the low pressure core cooling systems can reflood the core following certain postulated transients or accidents.

The design basis for Pilgrim's ADS accumulators required that they be able to provide 5 operations against atmospheric pressure or 2 against drywell design pressure. Under worse case design accident conditions (small and intermediate pipe breaks inside containment without HPCI) the most extensive mission time for ADS is less than 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and utilizing actual leak rate test data, the accumulators will provide sufficient capacity to actuate the pressure relief systen longer than the required tirre without recharging. The accumulators, associated piping and check valves are seismic category I.

In addition to the above, the pressure relief system could be utilized during the loss of shutdown cooling; however, this is a longer term requirement, on the order of days, and HPCI and/or RCIC are available alternatives for use until shutdown cooling is restored. Under these conditions, the pressure relief system is not required on a long tenn basis.

We believe this response meets the intent of this NUREG item and plan no further action in this area.

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II.K.3.44 Evaluation of-Anticipated Transients with-Single Failure to Verify No Fuel: Failure The following responds to an NRC letter from D. G. Eisenhut to all ~

applicants dated August 7,1981 concerning a request for additional ir. formation on NUREG-0737,. Item II.K.3.44. The letter requests a verification that the assumptions and initial conditions used in the generic analyses for Item II.K.3.44 as referenced in that-letter are-representative for Pilgrim Station.

We have reviewed the analysis assumptions and initial-conditions

_ used for the generic analysis and determined'that they'are repre-i sentative for Pilgrim Station.

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