ML20249A420

Submits Response to 980515 RAI Re Licensee Submittal of Relief Request RV-05 for IST Program

ML20249A420
Person / Time
Site:	LaSalle
Issue date:	06/12/1998
From:	Dacimo F COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9806160426
Download: ML20249A420 (4)

Text

- Commonwealth lilimn Company -

.- laSalle Generating Station

• "f*' 2601 Nonh 21M Road .

Marwillen, IL 613419757 Td fil5-357o761 -

June 12,1998 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555_.

Subject:

Submittal of Relief Request RV-05 for the Inservice Test Program LaSalle County Nuclear Power Station, Units 1 and 2 Facility Operating License NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374

References:

1. F. Dacimo letter to U.S. NRC, dated March 4,1998, LaSalle County Nuclear Station

- 2nd Ten-Year Interval Pump and Valve inservice Testing (IST) Program Plan, Revision 2

2. D. M. Skay letter to O. D. Kingsley, dated May 15,1998, transmitting a Request for

, Additional Information - LaSalle County Station Units 1 and 2 (TAC Nos. MA1117 and MA1118)

/

By your letter dated May 15,1998, you requested additional information regarding RV-05. Our response to the additional information is provided below.-

_Q1. Address whether the check valves' in question (1(2)PC001 A, B, C, -

and D) are capacity certified, if a check valve is not capacity certified, it can be classified as a check valve and tested in accordance with OM-10. if a check valve is a' capacity certified valve, then it can be classified as a pressure or vacuum relief device and tested in accordance with OM-1. The valves in . question.are not required to bel 4'(J[$ ' (as . tested a' vacuumin accordance with both OM-10 (as a check valv

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", relief' device). This clarification is provided on page.

4 l

A3-31 of "Summwy of Public Workshops Held in NRC Regions on -

M ' Inspection Procedure 73756, ' inservice Testing of Pumps and '

Valves,' and Answer to Panel Questions on Inservice Testing issues,"

dated July 18,1997.-

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Response

A subsequent review of the function of the subject valves (1(2)PC001 A, B, C, and D, Drywell to-Suppression Pool Vacuum Breaker Valves) have been completed. ' As indicated Reference 1, the subject valves are capacity.

certified, and therefore subject to the requirements of ASME/ ANSI OM, Part 1 ((OM-1),- as a vacuum relief device orily). As stated in your letter, .

since the valves _in question are capacity certified, they are not required to be

- tested in accordance with OM-10 (as a check valve). This is also supported by the clarification provided on page A3-31 of " Summary of Public

' Workshops Held in NRC Regions on 1nspection Procedure 73756, ' Inservice .

Testing of Pumps and Valves,' and Answer to Panel Questions on Inservice i Testing Issues," dated July 18,~ 1997.

Q2. For any valves that are capacity cettified, provide the following information: 1 2.1 in GL 87-09, the NRC stated its position that the structure of the technical specification accounts for entry into an LCO to l perform surveillance testing. If the time allowed for equipment to be out of service is not sufficient to perform a surveillance test, a technical specification change requesting additional out-of-service time to allow for surveillance would be required provided safety is not compromised by the increased out-of-service time. Discuss your reasons for not requesting a technical specification change in this case.

Response

As stated above, there are four vacuum breaker valves which provide redundancy for each Unit. Each of the subject valves are isolatable by means of butterfly valves installed upstream and downstream of each valve and pressure taps have been designed in the piping on both sides of each vacuum breaker. Thus, with only three out of the four vacuum breaker valves available, system availability is not effected up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. With these provisions, the LCO time allotted for this equipment to be out-of-service in Section 4.6.4.1 of the LaSalle County Nuclear Station Technical Specifications is sufficient to perform the required surveillance testing. Therefore, no request for additional out-of-service time is necessary as outlined in Generic Letter 87-09.

2.2 >

Address whether operators can manually manipulate one or -

more valves to restore a system to operate status in the event the system function is required during inservice testing.

Response

In the normal operating configuration the drywell-to-suppression pool vacuum breaker system, four valves (1(2)PC001 A, B, C, and D) are available to perform the required function. Thus, during the event that the system function is required, and with one vacuum breaker valve removed from service for inservice testing, testing will be halted and appropriate

, operator actions can be taken to manipulate the applicable valves to restore the system to an operable status, to ensure system availability is not compromised.

2.3 - Expand the discussion on the impracticality of verifying the vacuum breaker setpoints every six months using the guidelines in Sections 2.4.5 and 3.1 of NUREG-1482.

Response

As stated in Reference 1, we, Comed, identified that Valve Relief Request RV-05 (previously evaluated by the NRC as identified by letter dated December 8,1995) was revised. The previous revision of RV-05 requested relief fnom the exercise test requirements of ASME/ ANSI OM, Part 10 (OM-10) section 4.3.2. It was determined by the NRC that the proposed testing was not a deviation from the Code requirements.

During Revision 2 of the LCNS 2nd Ten-Year Interval Pump and Valve Inservice testing Program Plan, the subject valves were determined to be j capacity certified and therefore subject to the requirements of i ASME/ ANSI OM-1. As a result RV-05 was revised to request relief from the test requirements of Section 1.3.4.3(a) of OM-1.

The following reinforces why it is impractical to verify vacuum breaker set points using pressurized air every 6 months during plant operation. As identified in RV-05, installation of air supply hoses and the pressurization of a large volume of piping, and then blowdown of this air inventory into the nitrogen inerted drywell could require a power reduction due to oxygen concentrations exceeding the required limits as specified in LCNS Technical Specification 3.6.6.2. During refueling outages this technical specification is not required. Although these valves are not physically located in the inerted containment, the potential exists to de-inert the drywell during the performance of set point testing these valves at reactor power.

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Additionally, maintenance history of the subject valves tested at the 18 t

morith Technical Specification frequency indicated no frequent failures of these valves to relieve pressure as designed. Thus, the performance history of these valves to function as a vacuum relief, provides assurance and supports testing these at extended intervals without compromising safety.

Setpoint testing of these valves more frequently causes unnecessary cycling )

of these valves and provides no additionalincrease to safety.

Lastly, the 1995 Edition of ASME/ ANSI Code, Appendix 1, has been revised to increase the frequency of set-point testing pressure or vacuum relief devices from 6 months to 2 years. Therefore, set-point testing at an 18 month interval is consistent with, if not more frequent, than the two year test frequency outlined in section i 1.3.7 of mandatory Appendix I of the 1995 Edition of the ASME/ ANSI Code.

It is requested that the NRC evaluate the additional information provided above to support granting relief of RV-05 by July 1,1998. This will support the timely restart of LaSalle County Station Unit 1. L i

If there are any questions or comments conceming this letter, please refer them to Harold D. Pontious, Jr., Regulatory Assurance Manager, (815) 357-6761, extension 2383.

Respectfully, e_

Fred R. Dacimo Site Vice President LaSalle County Station cc: C. A. Paperiello, Acting NRC Region lll Administrator M. P. Huber, NRC Senior Resident inspector - LaSalle D. M. Skay, Project Manager - NRR - LaSalle C. H. Mathews, IDNS Resident inspector - LaSalle F. Niziolek, Office of Nuclear Facility Safety - lDNS

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