ML061720084

Response to NRC Request for Additional Information Regarding Technical Specification Changes to Revise Reactor Coolant Leakage Detection System Instrumentation

ML061720084
Person / Time
Site:	Pilgrim
Issue date:	06/14/2006
From:	Balduzzi M Entergy Nuclear Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2.06.053, TAC MC7255
Download: ML061720084 (4)

Text

AEt

'Entergy Entergy Nuclear Operations, Inc.

Pilgrim Nuclear Power Station 600 Rocky Hill Road Plymouth, MA 02360 Michael A. Balduzzi June 14, 2006 Site Vice President U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

Entergy Nuclear Operations, Inc.

Pilgrim Nuclear Power Station Docket 50-293 License No. DPR-35 Response to NRC Request for Additional Information Regarding Technical Specification Changes to Revise Reactor Coolant Leakage Detection System Instrumentation (TAC No. MC7255)

REFERENCE:

1. NRC Letter, 1.06.071, NRC Request for Additional Information Regarding Technical Specification Changes to Revise Reactor Coolant Leakage Detection System Instrumentation (TAC No.

MC7255), dated May 18, 2006.

LETTER NUMBER: 2.06.053

Dear Sir or Madam:

By Reference 1, the NRC requested additional information regarding proposed Technical Specification changes to revise reactor coolant leakage detection system instrumentation.

Entergy has evaluated the request and the response is provided in Attachment 1.

This letter contains no commitments.

Ifyou have any questions or require additional information, please contact Mr. Bryan Ford, Licensing Manager, at (508) 830-8403.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on the __day of T ,t. 2006.

Sincerely, Michael A. Balduzzi ERS/dm

Attachment:

1. Entergy Response to NRC Request for Additional Information Regarding Technical Specification Changes to Revise Reactor Coolant Leakage Detection System Instrumentation. (2 pages)

Entergy Nuclear Operations, Inc Letter Number 2.06.053 Pilgrim Nuclear Station Page 2 cc: Mr. James Shea, Project Manager Mr. Robert Walker, Director Plant Licensing Branch I-1 Massachusetts Department of Public Division of Operator Reactor Licensing Health Office of Nuclear Reactor Regulation Radiation Control Program U.S. Nuclear Regulatory Commission 90 Washington Street, 2 nd Floor One White Flint North O-8C2 Dorchester, MA 02121 11555 Rockville Pike Rockville, MD 20852 Regional Administrator, Region 1 Ms Cristine McCombs, Director U.S. Nuclear Regulator Commission Mass. Emergency Management Agency 475 Allendale Road 400 Worcester Road King of Prussia, PA 19406 Framingham, MA 01702 Senior Resident Inspector Pilgrim Nuclear Power Station to Letter 2.06.053 Page I of 2 Entergy Response to NRC Request for Additional Information Regarding Technical Specification Changes to Revise Reactor Coolant Leakage Detection System Instrumentation Pilgrim Leakage Detection Instrumentation Requirements &Actions NRC RAI I The proposedPilgrim TechnicalSpecification (TS) changes to the reactorcoolant system (RCS) leakage detection instrumentationwould remove the operability requirements of the drywell equipment drain sump from TS 3.6.C.2.a.1 and TS 3.6.C.2.b.1. Please explain how the total leakage limits as specified in TS 3.6.C.1.a.3 would be verified during plant operation.

Enterciv Response Pilgrim will continue to verify that total leakage is within limits using the same methods as currently used. This change seeks to remove the operability requirements for the drywell equipment drain sump from Technical Specifications. The drywell equipment drain sump associated pumps and instrumentation will continue to be used in conjunction with the drywell floor drain sump associated pumps and instrumentation to verify total leakage is within limits during plant operation.

NRC RAI 2 The proposedrevised Pilgrim TSs allow for an outage time of 30 days for the drywell floor drain sump. Please explain how TS 4.6.C.1 would verify the requirements of TS 3.6.C.1.a while the drywell floor drainsump is inoperable.

Entergy Response Pilgrim will use manual leak rate determination methods consistent with position (3) described in NRC Generic Letter (GL) 88-01, Supplement 1. GL 88-01 Supplement 1 provides the staff position concerning an acceptable allowed out of service time for the drywell floor drain sump. Position (3) discusses that leakage can be determined by measuring the differences in sump level during the 30 day period when the drain sump monitoring system is inoperable. This method is valid for Pilgrim because sump volume is known and has installed instrumentation that can be used to determine sump level for use in calculating leakage rates. In fact, at very low leakage rates, indicative of a well maintained RCS, this is in effect the method that must be used for determining leakage rates because even with the sump operable, there can be insufficient liquid in the floor drain sump to operate the pumps every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

Attachment 1 to Letter 2.06.053 Page 2 of 2 Entergy Response to NRC Request for Additional Information Regarding Technical Specification Changes to Revise Reactor Coolant Leakage Detection System Instrumentation RCS Proposed Leakaqe Actions The NRC Standard Technical Specifications(STS) Surveillance Requirement (SR) 3.4.4.1 states the following, "Verify RCS unidentifiedand total LEAKAGE and unidentified LEAKAGE increase are within limits [every 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />s]." The proposed Pilgrim SR 4.6.C.1 consists of the following statement, "Demonstratedrywell leakage is within the limits specified in 3.6.C. 1 at least once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />." It is not clear to the staff that the proposed Pilgrim SR is consistent with the STS.

NRC RAI 3 Provide clarificationon how the proposedPilgrim SR 4.6.C.1 is equivalent to STS SR 3.4.4.1.

Entergy Response Although the wording of SR 3.6.C.1 in Pilgrim's Custom Technical Specifications is different in this case than the corresponding wording of STS SR 3.4.4.1, comparison reveals that the two SRs are equivalent. While the STS SR 3.4.4.1 identifies by name each type of leakage to be verified, Pilgrim SR 4.6.C.1 explicitly calls out "the limits specified in 3.6.C.1" which are the same as those called out in STS SR 3.4.4.1 by name.

Inthis regard the two SRs are equivalent, although they are expressed differently.

NRC RAI 4 With the dry well sump monitoringsystem inoperable,how canyou demonstrate that totalleakage and the unidentifiedleakage increaseare within the TS specified limits?

Enterqgy Response As discussed in the response to RAI#2 above, Pilgrim will use manual leak rate determination methods consistent with position (3) described in NRC Generic Letter (GL) 88-01, Supplement 1. GL 88-01 Supplement 1 provides the staff position concerning an acceptable allowed out of service time for the drywell floor drain sump. Position (3) discusses that leakage can be determined by measuring the differences in sump level during the 30 day period when the drain sump monitoring system is inoperable. This method is valid for Pilgrim because sump volume is known and has installed instrumentation that can be used to determine sump level for use in calculating leakage rates. Infact, at very low leakage rates, indicative of a well maintained RCS, this is in effect the method that must be used for determining leakage rates because even with the sump operable, there can be insufficient liquid in the floor drain sump to operate the pumps every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.