ML17270A274

Supplemental Information Regarding LaSalle County Station License Amendment Request for Extension of Type a and Type C Containment Leak Rate Test Intervals

ML17270A274
Person / Time
Site:	LaSalle
Issue date:	09/27/2017
From:	Gullott D M Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-17-131
Download: ML17270A274 (5)

Text

Exelon Generation RS-17-131 10 CFR 50.90 September 27, 2017 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374

Subject:

Supplemental Information Regarding LaSalle County Station License Amendment Request for Extension of Type A and Type C Containment Leak Rate Test Intervals

References:

1) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, 11License Amendment Request to Revise Technical Specifications 5.5.13, 1Primary Containment Leakage Rate Testing Program,' for Permanent Extension of Type A and Type C Leak Rate Test Frequencies,11 dated October 26, 2016 (ADAMS Accession No. ML 16300A200) 2) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, 11Supplement to License Amendment Request for Permanent Extension of Type A and Type C Leak Rate Test Frequencies Regarding Hardened Containment Vent System (HCVS) Modifications and Installation of Primary Containment Isolation Valves (PCIVs), 11 dated February 16, 2016 (ADAMS Accession No. ML 17048A255) 3) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, 11Response to Request for Additional Information Regarding LaSalle County Station License Amendment Request for Extension of Type A and Type C Containment Leak Rate Test Intervals (SBPB Branch),11 dated July 17, 2017 (ADAMS Accession No. ML17200C944) 4) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, 11Response to Request for Additional Information Regarding LaSalle County Station License Amendment Request for Extension of Type A and Type C Containment Leak Rate Test Intervals (PRA Branch),11 dated August 8, 2017 (ADAMS Accession No. ML 17220A 168)

September 27, 2017 U.S. Nuclear Regulatory Commission Page2 By a letter to the U.S. Nuclear Regulatory Commission (NRC) dated October 26, 2016, (Reference 1 ), Exelon Generation Company, LLC (EGC) submitted an amendment request for LaSalle County Station (LSCS), Units 1 and 2. The proposed amendment would revise the Technical Specifications {TS) 5.5.13, 11Primary Containment Leakage Rate Testing Program,11 to allow for the permanent extension of the Type A integrated leak rate testing (ILRT) and Type C leak rate testing frequencies. This request was supplemented by EGC letters dated February 16, July 17, and August 8, 2017 (References 2, 3, and 4). As discussed during a conference call with the NRC on September 19, 2017, additional supplemental information is being provided to support the NRC's review of the EGC request submitted on October 26, 2016 (Reference 1) and the supplement submitted July 17, 2017 (Reference 3). The Attachment to this letter provides the supplemental information. EGC has reviewed the information supporting a finding of no significant hazards consideration that was previously provided to the N RC in Attachment 1 of Reference 1 . The supplemental information provided in this submittal does not affect the bases for concluding that the proposed license amendment request does not involve a significant hazards consideration. In accordance with 1 O CFR 50.91, 11Notice for public comment; State consultation," paragraph (b), EGC is notifying the State of Illinois of this application for license amendment by transmitting a copy of this letter and its Attachment to the designated State Official. There are no regulatory commitments contained within this letter. Should you have any questions concerning this letter, please contact Ms. Lisa A. Simpson at (630) 657-2815. I declare under penalty of perjury that the foregoing is true and correct. Executed on the 27th day of September 2017. Respectfully, David M. Gullatt Manager -Licensing Exelon Generation Company, LLC

Attachment:

Supplemental Information cc: NRC Regional Administrator, Region Ill NRC Senior Resident Inspector, LaSalle County Station Illinois Emergency Management Agency -Division of Nuclear Safety ATTACHMENT Supplemental Information By a letter to the U.S. Nuclear Regulatory Commission (NRC) dated October 26, 2016, Exelon Generation Company, LLC (EGC) submitted an amendment request to revise the Technical Specifications (TS) 5.5.13, 11Primary Containment Leakage Rate Testing Program,11 to allow for the permanent extension of the Type A integrated leak rate testing (ILRT) and Type C leak rate testing frequencies for LaSalle County Station (LSCS), Units 1 and 2. This request was supplemented by EGC letters dated February 16, July 17, and August 8, 2017 (References 2, 3, and 4). As discussed during a conference call with the NRC on September 19, 2017, supplemental information is being provided to support the N RC's review of the EGC request submitted on October 26, 2016 (Reference 1) and the supplement submitted July 17, 2017 (Reference 3). This information is provided for the purposes of correction and clarification.

References:

1) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, 11License Amendment Request to Revise Technical Specifications 5.5.13, 'Primary Containment Leakage Rate Testing Program,' for Permanent Extension of Type A and Type C Leak Rate Test Frequencies,11 dated October 26, 2016 (ADAMS Accession No. ML 16300A200) 2) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "Supplement to License Amendment Request for Permanent Extension of Type A and Type C Leak Rate Test Frequencies Regarding Hardened Containment Vent System (HCVS) Modifications and Installation of Primary Containment Isolation Valves (PCIVs), 11 dated February 16, 2016 (ADAMS Accession No. ML 17048A255) 3) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, 11Response to Request for Additional Information Regarding LaSalle County Station License Amendment Request for Extension of Type A and Type C Containment Leak Rate Test Intervals (SBPB Branch)," dated July 17, 2017 (ADAMS Accession No. ML 17200C944) 4) Letter from D. M. Gullatt (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "Response to Request for Additional Information Regarding LaSalle County Station License Amendment Request for Extension of Type A and Type C Containment Leak Rate Test Intervals (PRA Branch),11 dated August 8, 2017 (ADAMS Accession No. ML 17220A 168) 5) Letter from C. Gratton (U.S. Nuclear Regulatory Commission) to M. J. Pacilio (Exelon Nuclear), "LaSalle County Station, Units 1 and 2 -Issuance of Amendments Re: Application of Alternative Source Term (TAC Nos. ME0068 and ME0069, 11 dated September 16, 2016 (ADAMS Accession No. ML 101750625) The N RC is seeking clarification regarding the following items. Page 1 of 3 ATTACHMENT Supplemental Information Tables 3.2.5-1 and 3.2.5-2 of Reference 1 state that the acceptance limit is 0.634 wt.%/day. The EGC Response to SBPB RAl-1 of Reference 3 states that the acceptance criterion is 0.635 wt.%/day.

• The acceptance limit of 0.634 wt.%/day listed in Reference 1 was in error. This was the result of a typographical error in the source document used to support the development of the license amendment request. The correct acceptance limit, which has been validated by EGC staff against past test data, is 0.635 wt.%/day. Therefore, the value included in Reference 3 is correct. The Total Leakage provided in Tables 3.2.5-1 and 3.2.5-2 of Reference 1 vary from the values provided in the EGC Response to SBPB RAl-1 of Reference 3.

• The 1994 and 2008 leakage rates for Unit 1 and 1993 and 2009 leakage rates for Unit 2 provided in the EGC Response to SBPB RAl-1 of Reference 3 are correct. The reason for the discrepancy in the values between Reference 1 and Reference 3 was the use of secondary source test data to develop Reference 1 instead of utilizing the actual test result reports (as was done for Reference 3).

• EGC has subsequently reviewed the test result reports for the first four Type A Unit 1 and first four Type A Unit 2 tests referenced in Tables 3.2.5-1 and 3.2.5-2 of Reference 1. EGC could not validate the eight specific Total Leakage values referenced in Reference 1. Through test report review, EGC has validated satisfactory results (i.e., acceptance criterion met) for seven of the eight Type A tests. The Unit 2 1990 Type A as-found test was found to be greater than the acceptance limit of 0.635 wt. %/day as a result of excessive leakage found at a local leak tested penetration or isolation valve. Corrective actions were taken, with a local leak rate test (LLRT) performed before and after, which resulted in satisfactory as-left total leakage results. Section 3.4.5 of Reference 1 includes a sentence that states. "In accordance with TS 5.5.13, the containment leakage rate, as determined by totaling the leakages of all Type B and Type C LLRTs (exclusive of the main steam lines and personnel access door seals). must be less than or equal to 0.6 La or 384.2 standard cubic ft per hour (SCFH).11

• EGC has confirmed that 0.6 La is equal to 384.2 SCFH based on EGC program procedure LTS-300-4, "Unit 1 (2) Primary Containment Integrated Leak Rate Test (ILRT).11 EGC proposes the following clarification to this sentence (emphasis added): In accordance with TS 5.5.13, the containment leakage rate, as determined by totaling the leakages of all Type Band Type C LLRTs (exclusive of the main steam lines and personnel access door seals), must be less than or equal to 0.6 La, which is equivalent to 384.2 standard cubic ft per hour (SCFH). The leakage acceptance value, La, is equivalent to 640.4 SCFH. Page 2 of 3 ATTACHMENT Supplemental Information

• EGC has validated that Tables 3.4.5-1 and 3.4.5-2 are correct as stated in Reference 1. The percentages shown in Tables 3.4.5-1 and 3.4.5-2 are based on 364.2 SCFH to provide a conservative total with margin.

• The leakage acceptance value, La, changed from 0.635 to 1.0 with the approval of Alternative Source Term (AST) on September 6, 2010 (Reference 5). Page 3 of 3