ML14163A482

Response to Request for Additional Information Regarding License Amendment Request to Change Emergency Core Cooling Systems Surveillance Requirements

ML14163A482
Person / Time
Site:	Columbia
Issue date:	05/29/2014
From:	Javorik A Energy Northwest
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
G02-14-088
Download: ML14163A482 (4)

Text

Alex L. Javorik ENERGY Columbia Generating Station P.O. Box 968, PE04 NORTHWEST Richland, WA 99352-0968 Ph. 509.377.8555 I F. 509.377.4150 aljavork@ energy-northwest.com MAY 2 9 2014 G02-14-088 10 CFR 50.90 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

COLUMBIA GENERATING STATION, DOCKET NO. 50-397 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO CHANGE EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS

Reference:

1. Letter, G02-13-151, dated October 31, 2013, AL Javorik (Energy Northwest) to NRC, "License Amendment Request for Change to Emergency Core Cooling Systems Surveillance Requirements"

2. Letter, dated April 29, 2014, CF Lyon (NRC) to ME Reddemann (Energy Northwest), "Columbia Generating Station - Request for Additional Information Related to License Amendment Request for Change to Emergency Core Cooling Systems Surveillance p Requirements (TAC No. MF3055)"

Dear Sir or Madam:

By Reference 1, Energy Northwest requested approval of a license amendment request to revise Technical Specification (TS) Surveillance Requirements 3.5.1.4 and 3.5.2.5.

Via Reference 2, the Nuclear Regulatory Commission (NRC) requested additional information. Attachment 1 provides the response to the requested information.

This letter and its attachments contain no regulatory commitments. If there are any questions or if additional information is needed, please contact Ms. L. L. Williams, Licensing Supervisor, at 509-377-8148.

I declare under penalty of perjury that te and correct.

Executed .ý- V,- I t A. L. Javorik Vice President, Engineering P~4iZL

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO CHANGE EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS Page 2 of 2

Attachment:

As stated cc: NRC RIV Regional Administrator, NRC NRR Project Manager NRC Senior .Resident Inspector/988C JO Luce - ESFEC (email)

RR Cowley - WDOH (email)

MA Jones - BPA/1.399 (email)

-4 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO CHANGE EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS Attachment 1 Page 1 of 2 NRC ReoUost:

1. NEDO-33813, Revision 2, "Technical Specification Change Support for RHR/LPCI and LPCS Flow Rate Long-Term LOCA [Loss-of-Coolant Accident]

Containment Response and ECCS [Emergency Core Cooling System]/Non-LOCA Evaluations," September 2013 (ADAMS Accession No. ML13316A010),

Section 4.1.7, Refueling Operations and Spent Fuel Pool Cooling Assessment, states that refueling operations and spent fuel pool cooling may be affected if there is a reduction in the RHR heat exchanger heat removal capacity as a result of RHR/LPCI and LPCS flow rate reduction. NEDO-33813, Revision 2 also indicates that these evaluations were not included with the report, and that the assessments would be made by Energy Northwest outside of this report.

Please provide the assessments for refueling operations and spent fuel pool cooling to determine acceptability.

Energy Northwest Resmone:

Three situations describe Columbia Generating Station's (Columbia's) refueling and spent fuel pool cooling operations: 1) the use of shutdown cooling for heat removal from the reactor core during refueling, 2) the use of the Fuel Pool Cooling (FPC) system during normal reactor operations and refueling outages to cool the spent fuel pool, and

3) the use of the Residual Heat Removal (RHR) system to provide supplemental cooling during a full core offload. A discussion of the impact of the flow rate reduction for RHR on each situation is provided below. There is no impact from the flow rate reduction for the Low Pressure Core Spray (LPCS) system since it does not support refueling operations and spent fuel pool cooling.

1. NEDO-33813 Sections 4.1.5 and 4.1.6 provide an evaluation of the impact of the change on the shutdown cooling and alternate shutdown cooling modes of operation of RHR. These evaluations are directly applicable during refueling operations while using shutdown cooling for decay heat removal of the reactor core given Columbia's configuration.

2, During normal reactor operation (non-outage) and refueling operations not involving a full core off load, the FPC system is designed to remove decay heat released from the stored spent fuel elements and maintain a specified fuel pool water temperature and water level. The RHR system is not credited for supplemental cooling of the spent fuel pool other than for a full core offload to the pool.

3. During refueling, in the event of a full core offload, additional heat removal capacity is available from the B loop of the RHR system. To provide

RESPONSE TO. REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO CHANGE EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS Page 2 of 2 supplemental cooling to the spent fuel pool, the RHR flow is throttled to 5400-5600 gpm during system realignment and then is further limited to less than or equal to 3000 gpm during the FPC Assist mode. Since these flow rates are less than the new lower Technical Specification flow rate of 7200 gpm, the relaxed RHR flow rate has no adverse effect on the supplemental cooling to the spent fuel pool.