ML101170589
| ML101170589 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 04/27/2010 |
| From: | Price J Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 10-236 | |
| Download: ML101170589 (6) | |
Text
10 CFR 50.55a VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 April 27, 2010 U.S. Nuclear Regulatory Commission Serial No.10-236 Attention: Document Control Desk NL&OS/ETS RO Washington, D.C. 2055!5 Docket Nos. 50-338/339 License Nos. NPF-4/7 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)
NORTH ANNA POWER STATION UNITS 1 AND 2 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FOURTH INTERVAL INSERVICE TESTING PROGRAM PLAN AND PROPOSED ALTE:RNATIVES AND RELIEF REQUESTS In a November 24, 2009 letter (Serial No.09-715), Dominion submitted the Fourth Interval Inservice Testing (1ST) Program Plans for North Anna Power Station Units 1 and 2. Pursuant to 10 CFR 50.55a(f)(4)(ii), the 1ST programs were updated to comply with the ASME Code for Operations and Maintenance of Nuclear Power Plants 2004 Edition. The attachments to that letter included the 1ST Program Plans, which described the programmatic aspects of the 1ST programs, and included the associated proposed alternatives and relief requests for the fourth interval. In an April 6, 2010 e-mail from Dr. V. Sreenivas, the NRC requested additional information to complete the review of the proposed alternatives and relief requests. In a follow-up phone call with the NRC for clarification of the request for additional information, Dominion agreed to revise and resubmit Pump Relief Request P-1 for both North Anna Units 1 and 2.
The fourth 1ST interval will begin on December 15, 2010 and North Anna Units 1 and 2 will begin implementation of the plans on that date. Therefore, Dominion continues to request review and approval of the relief requests by December 1, 2010.
If you have any questions or require additional information, please contact Mr. Thomas Shaub at (804) 273-2763.
RespectfuIly, Commitments made in this letter: None
Attachment:
Response to Request For Additional Information Fourth Interval Inservice Testing REdief Requests
Serial No.10-236 Docket Nos. 50-338/339 Response to RAls 1ST Relief Requests Page 2 of 2 cc: U.S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Avenue, NE Suite 1200 Atlanta, Georgia ~m303-1257 Mr. J. E. Reasor, .lr, Old Dominion Electric Cooperative Innsbrook Corporate Center 4201 Dominion Blvd.
Suite 300 Glen Allen, Virginia 23060 NRC Senior Resident Inspector North Anna Power Station Ms. K. R. Cotton NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 0-8 G9A 11555 Rockville Pike Rockville, Maryland 20852 Dr. V. Sreenivas NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 0-8 G9A 11555 Rockville Pike Rockville, Maryland 20852
Serial No.10-236 Docket Nos. 50-338/339 Response to RAls 1ST Relief Requests Attachment RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FOURTH INTERVAL INSERVICE TESTING RELIEF REQUESTS North Anna Power Station Units 1 and 2 Virginia Electric and Power Company (Dominion)
Serial No.10-236 Response to RAls 1ST Relief Requests Page 1 of 3 REQUEST FOR ADDITIONAL INFORMATION (RAn FOR NORTH ANNA POWER STATIONS (NAPS)
(TAC Nos ME2748, ME2749, ME2753 thru ME2760, ME2763 thru ME2772, and ME2776 thru ME2789)
BACKGROUND By letter dated NovembHr 24, 2009 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML093350600), Virginia Electric and Power Company submitted Fourth Interval Inservice Testing (1ST) Program Relief Requests P-1 thru P-8 for pumps, and V-1 thru V-3 for valves for North Anna Power Station Units 1 and 2. In an April 6, 2010, e-mail from Dr. V. Sreenivas, the NRC requested additional information to complete the review of the proposed 1ST relief requests. The following information is provided to address the NRC concerns/questions.
Response to Request for Additional Information RAI P-1-1:
Pump Relief Request No. P-1, Section 4.0, Reason for Request, first paragraph, second line states "There is at least one pump in each group with at least one vibration reference value (Vr) that is currently less than 0.05 inch per second (ips). Please specify and clarify which pump(s) from each of the pump groups have vibration reference value less than 0.05 ips, because this relief request is only applicable to pumps whose measurecl reference value (Vr) is less than 0.05 ips.
Dominion Response:
As a result of the April 8, 2010 teleconference between representatives of the NRC and Dominion, it is understood that relief will be restricted to only those pumps that have at least one Vr value that is currently below 0.05 ips. Therefore, North Anna Power Station will revise Pump Relief Requests No. P-1 for North Anna Units 1 and 2 to include only the pumps that have Vr value(s) currently below 0.05 ips, and resubmit the relief requests.
RAI P-1-2:
Pump Relief Request l\Jo. P-1, Section 4.0, Reason for Request, third paragraph, second line states "This minimum value will be applied to individual vibration locations for the pumps listed in Table P-1 where the measured reference value is less than 0.05 ips." Please verify and confirm that each pump listed in Table P-1 has at least one reference value less than 0.05 ips.
Serial No.10-236 Response to RAls 1ST Relief Requests Page 2 of 3 Dominion Response:
During the revision of Pump Relief Request No. P-1 for North Anna Units 1 and 2, the measured reference values will be verified and confirmed to be less than 0.05 ips for the pumps listed in the revised relief requests.
RAI P-1-3:
Pump Relief Request No. P-1, Section 4.0, Reason for Request, does not include information on (1) bearing temperature measurement and trending; (2) thermography analysis; and (3) enhanced vibration monitoring, as part of NAPS Predictive Maintenance Program (PdM). Please confirm that the PdM at NAPS, Units 1 and 2 includes information such as bearing temperature trending, thermographic analysis, and enhanced vibration monitoring.
Dominion Response:
References to bearing temperature measurement and trending, and thermography analysis were not included in Pump Relief Request No. P-1 because these monitoring assessments are not performed routinely, but rather are used on a limited basis for diagnostic evaluations. Therefore, it was concluded that the description in Section 4.0, Reason for Request, was more accurately conveyed without crediting these diagnostic activities.
For vibration monitoring, the NAPS PdM program employs techniques used typically for monitoring and analysis of plant rotating equipment. This technology analyzes and trends displacement, veocity, and acceleration vibration patterns to predict the need to correct problems in rotating equipment such as degraded bearings, improper alignments, and out-of-balance or worn components prior to equipment failure. This enhanced vibration monitoring program is applied to the 1ST program pumps.
RAI P-1-4:
Pump Relief Request No. P-1, Section 7.0, Precedents, the last paragraph, states that "Note that Relief Request P-1 applies to all pumps within the group listed in Table P-1.
Pumps 1-CH-P-1B, 1-HV-P-20C and 1-RS-P-3B for NAPS Unit 1, and 2-CH-P-1A, 2-CH-P-1 C, 2-FW-P-3B, 2-HV-P-20C and 2-SI-P-1 B for NAPS Unit 2 do not have a measured reference value below 0.05 ips for a particular vibration location but are included in the relief request scope." Please provide the measured reference values for these pumps.
Serial No.10-236 Response to RAls 1ST Relief Requests Page 3 of 3 Dominion Response:
As discussed in the response to RAI P-1-1 above, Pump Relief Request No. P-1 for North Anna Units 1 and 2 will be revised to list only pumps that have Vr valuers) currently below 0.05 ips.
RAI-P-5-1 :
Pump Relief Request No. P-5, Section 5.0, Proposed Alternative and Bases for Use, second paragraph, first line states "The removal of quarterly flow testing of these pumps has been deemed acceptable per NRC Generic Letter (GL) 89-04, Position 9". Please note that the use of GL. 89-04, Position 9 requires that data (differential pressure and vibration) collected during minimum-flow testing (quarterly) and data from full flow (cold-shutdown or refueling outage) should be trended as required by IWP-6000 (Now it is ISTB-6000). Relief Request P-5 does not discuss trending of the measured data while using GL 89-04, Position 9. Please confirm that the trending of measured data will be performed at NAPS, Units 1 and 2 for P-5 as required by GL 89-04, Position 9.
Dominion Response:
North Anna Power Station will trend the measured data described in Pump Relief Request No. P-5 as required by ISTB-6000.
RAI-P-6-1 :
Pump Relief Request No. P-6, Section 4.0, Reason for Request, ISTB-3300(e)(1), first paragraph, fourth line states that the "The LOCA containment analysis flow rate of 3350 gpm will be used as the pump design flow." In the NAPS, Units 1 and 2 previous (third) 10-year 1ST program, the design flow used for these pumps 1-RS-P-2A12B and 2-RS-P-2A12B was 3640 gpm. Please explain the different design flow values for these pumps.
Dominion Response:
The third interval 1ST program relief request references two flow rates, the design flow rate of 3640 gpm, and the safety analysis flow rate of 3450 gpm. The design flow rate of 3640 gpm is related to the pump capacity. The safety analysis flow rate should be considered the pump desiqn flow rate referenced in the ASME OM Code, Subsection ISTB because this is the flow rate the pump must deliver to satisfy the assumptions made in the safety analysis. The safety analysis minimum flow rate was reduced from 3450 gpm to 3350 gprn because of the increased design basis head losses on the suction side of the pumps as a result of the NRC GSI-191 containment sump strainer modifications. The UFSAR safety analysis was changed to reflect the reduction in the delivered flow requirements for the outside recirculation spray pumps.