NL-13-0295, Request to Revise the Plant Service Water Pump Well Minimum Water Level Response to Request for Additional Information Regarding Pump Minimum Submergence and Technical Specifications

Request to Revise the Plant Service Water Pump Well Minimum Water Level Response to Request for Additional Information Regarding Pump Minimum Submergence and Technical Specifications

ML13053A493
Person / Time
Site:	Hatch
Issue date:	02/22/2013
From:	Pierce C Southern Co, Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-13-0295, TAC ME9004, TAC ME9005
Download: ML13053A493 (5)

Text

Charles R. Pierce Southern Nuclear Regulatory Affairs Director Operating Company, Inc.

40 Inverness Center Parkway Post Office Box 1295 Birmingham, Alabama 3521]1 Tel 205.992.7872 Fax 205.992.7601 SOUTHERN . \

COMPANY February 22, 2013 Docket 1\1 os. : 50-321 NL-13-0295 50-366 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant Request to Revise the Plant Service Water Pump Well Minimum Water Level Response to Request for Additional Information Regarding Pump Minimum Submergence and Technical Specifications Ladies and Gentlemen:

By letter dated July 5, 2012, Southern Nuclear Operating Company (SNC) requested amendments to the Edwin I. Hatch Nuclear Plant (HNP) Units 1 and 2 Technical Specifications (TS) (TAC NOS ME9004 and ME9005). The proposed amendments would revise the minimum water level referenced in the Units 1 and 2 TS Surveillance Requirement (SR) associated with the Limiting Condition for Operation (LCO) for the plant service water (pSW) system and ultimate heat sink (UHS) (LCO 3.7.2).

By letter dated October 15, 2012, the NRC requested additional information regarding the minimum submergence values for the pumps located in the HNP intake structure and plant service water pump throttling requirements that were formerly in the HNP TS. By letter dated November 13, 2012, SNC provided the response to the information requested.

By letter dated January 28, 2013, the NRC requested additional information regarding operator actions and minimum water levels referenced in applicable drawings. The enclosure provides the response to the NRC request for additional information (RAI).

This letter contains no NRC commitments. If you have any questions, please contact Ken McElroy at (205) 992-7369.

U. S. Nuclear Regulatory Commission NL-13-0295 Page 2 Mr. C. R. Pierce states he is Regulatory Affairs Director of Southern Nuclear Operating Company, is authorized to execute this oath on behalf of Southern Nuclear Operating Company and, to the best of his knowledge and belief, the facts set forth in this letter are true.

Respectfully submitted, C.R. Pierce Regulatory Affairs Director CRP/rmj/lac Sworn 0 and SUbscribetfefore me thiS(~ !J,-J day of c+~

n ~ I") I . . . n ,.

, 2013.

r U rzJVL My commission expires: / /- 0 2 -dO I '3

Enclosure:

1. Response to Request for Additional Information Regarding Pump Minimum Submergence and Technical Specifications cc: Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President & Chief Nuclear Officer Mr. D. R. Madison, Vice President - Hatch Mr. B. L. Ivey, Vice President - Regulatory Affairs Mr. B. J. Adams, Vice President - Fleet Operations RType: CHA02.004 U. S. Nuclear Regulatory Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager - Fleet Mr. E. D. Morris, Senior Resident Inspector - Hatch State of Georgia Mr. J. H. Turner, Environmental Director Protection Division

Edwin I. Hatch Nuclear Plant Request to Revise the Plant Service Water Pump Well Minimum Water Level Response to Request for Additional Information Regarding Pump Minimum Submergence and Technical Specifications Level Enclosure 1 Response to Request for Additional Information Regarding Pump Minimum Submergence and Technical Specifications

Enclosure 1 to NL-13-0295 RAI Response - Regarding Pump Minimum Water Level NRC RAI #1 The minimum water level for the Plant 8ervice Water pumps is stated to be 59.1 feet considering a 4500 gallon per minute (gpm) flow rate. 8NC procedures call for reducing pump flow to not exceed 7000 gpm when level is less than 61.2 feet.

8NC provided no assurance that flow has been reduced to 4500 gpm although it is stated that only 4428 gpm is required for shutdown cooldown. Please clarify.

SNC Response The 7000 gpm limitation is for normal plant operation when the turbine building component heat exchangers are in service. By design, the turbine building P8W isolation valves receive a close signal for a design basis accident (LOCA and/or L08P). With the turbine building isolation valves closed, system hydraulics prevent a P8W pump from exceeding 4500 gpm. Therefore, procedural throttling limitations are not required for design basis accidents.

NRC RAI #2 The minimum water level for the residual heat removal service water (RHR8W) pumps is stated to be 59.8 feet, yet drawings 8-56317 and 8-60315 state the minimum water level is 60.5 feet. Drawing 8-56317 lists a minimum submergence of 35 inches for a flow rate of 4000 gPfTl. Apparently 8NC used 35 inches for a flow rate of 4400 gpm? If so, why is 59.8 feet the minimum water level for the RHR8W pumps considering that the drawings indicate 60.5 feet and the actual flow rate is 4400 versus 4000 gpm?

SNC Response Drawings 8-56317 and 8-60315 are vendor drawings. The drawings provide a minimum water level of 60.5 feet as well as a maximum high water level of 91.3 feet. These values are not licensing or design bases values. The values were placed on the drawings by the vendor and reflect information that was provided in the original pump specifications to indicate minimum and maximum water levels expected in the pump well. These water levels are not related to pump performance. The minimum submergence of 35 inches for a flow rate of 4000 gpm currently provided on drawing 8-56317 represents the minimum submergence for a flow rate of 4000 gpm previously provided by the pump vendor. Due to a requirement to evaluate the pump at a flow rate of 4400 gpm, the vendor was requested to provide the minimum submergence at a flow rate of 4400 gpm. The vendor response stated that a minimum submergence of 34 inches is required at a flow rate of 4400 gpm and a minimum submergence of 31 inches is required at a flow rate of 4000 gpm. 8ince our previous analysis was based on 35 inches, we continued to use 35 inches for consistency and conservatism. An action item has been generated to revise the information on the drawings.

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Pump Minimum Water level water for standby service water pump is 60.0 gpm flow rate and 1.0 foot minimum submergence.

\JH-"'-"T 08 1.0 as the minimum submergence for a water pump is delivering 850 gpm a minimum submergence of 1.0 foot, why is 60.0 service water pumps?

flowrate of Standby Service Water pump is 700 gpm. Due to a requirement to evaluate the pump at a flow rate of 850 gpm, the vendor was

.... "'i;:l'L"'U to the minimum submergence at a flow rate of 850 gpm.

that a minimum submergence of 12 inches is 700 and gpm. An action item has been generated to clarify drawing.

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