ML070650298

Edwin I Hatch Nuclear Plant, Units 1 and 2 (HNP) - Request for Additional Information Alternative Source Term Application

ML070650298
Person / Time
Site:	Hatch
Issue date:	03/15/2007
From:	Martin R NRC/NRR/ADRO/DORL/LPLII-1
To:	Madison D Southern Nuclear Operating Co
Martin R, NRR/DORL, 415-1493
References
TAC MD2934, TAC MD2935
Download: ML070650298 (6)

Text

March 15, 2007 Mr. Dennis R. Madison Vice President - Hatch Edwin I. Hatch Nuclear Plant 11028 Hatch Parkway North Baxley, GA 31513

SUBJECT:

EDWIN I. HATCH NUCLEAR PLANT, UNIT NOS. 1 AND 2 (HNP) - REQUEST FOR ADDITIONAL INFORMATION (RAI) REGARDING ALTERNATE SOURCE TERM APPLICATION (TAC NOS. MD2934 AND MD2935)

Dear Mr. Madison:

By letter to the Nuclear Regulatory Commission dated August 29, 2006, Southern Nuclear Operating Company, Inc., proposed to revise the Edwin I. Hatch Nuclear Plant, Units 1 and 2, licensing and design basis with a full scope implementation of an alternative source term. We have reviewed your application and have identified a need for additional information as set forth in the Enclosure.

We discussed this issue with your staff on March 12, 2007. Your staff indicated that it plans to submit a response to this issue within sixty (60) days of receipt of this letter.

Sincerely,

/RA/

Robert E. Martin, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-321 and 50-366

Enclosure:

RAI cc w/encl: See next page

- ML070650298

• transmitted by memo dated OFFICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRR/SBPB/BC NRR/LPL2-1/BC NAME RMartin MOBrien JSegala by memo EMarinos DATE 03/13/07 03/15 /07 02/22/07*

03/13 /07

REQUEST FOR ADDITIONAL INFORMATION CONCERNING IMPLEMENTATION OF AN ALTERNATIVE SOURCE TERM FOR EDWIN I. HATCH NUCLEAR PLANT, UNIT NO. 1 1.

The "BWROG [Boiling Water Reactor Owners Group] Report for Increasing [Main Steam Isolation Valve] MSIV Leakage Rate Limits and Elimination of Leakage Control Systems," states "Individual licensees should provide a detailed description of the alternate MSIV leakage treatment pathway and the basis for its functional reliability, commensurate with its intended safety-related function. (This includes the requirement to demonstrate that MSIV leakage will be successfully transported to the condenser by demonstrating that other potential release paths can be isolated)."

In the attachment, "Edwin I. Hatch Nuclear Plant Unit 1 Main Steam Isolation Valve Alternate Leakage Treatment [ALT] Path Description and Seismic Evaluation," on page 1, of the above report information is provided to ensure that the ALT pathway boundary is isolated and that the release is via the condenser. When the list of valves that close automatically and those that require operator action to be closed is compared to Figure 1, "Schematic of the Alternate Leakage Treatment (ALT) Path," a path still exists to "CRW" through valves 1N11-F004 and 1N11-F042.

A.

Please define the Acronym "CRW" as it is not defined in the submittal.

B.

Please provide justification for why provisions to isolate the potential release path to "CRW" are not provided.

C.

Please confirm that "Sample Panel 1H21-P204" provides an adequate boundary which can be relied upon in the event of a loss-of-coolant accident, and does not require additional isolation.

2.

To isolate the boundary and ensure potential release paths do not exist, local operator actions are required to close certain valves. Please confirm that operators will be able to access and manipulate these valves when required, in all conditions (e.g. radiological, environmental) during postulated accidents and transients that credit the ALT pathway.

3.

Section 5.1 of the NRC staff's safety evaluation of the "BWROG Report for Increasing MSIV Leakage Rate Limits and Elimination of Leakage Control Systems," states "The licensees should also address the radiological aspects of MSIV leakage treatment following a LOCA, coincident with a loss of offsite power assuming the worst case single active failure. This is a design basis event for which the radiological consequences must be shown to be less than the regulatory limits for offsite and onsite (control room) doses." Please explain how the single failure criterion is satisfied when establishing the ALT flow path and isolation boundaries. Also, confirm that valves and other components that make up the ALT flow path and isolation boundaries will not leak in this mode of operation (such as through valve pistons or hinge pins that rely upon steam pressure for establishing a leak-tight seal), or alternatively explain how any leakage of this nature is accounted for in the onsite and offsite dose analyses to assure conservative results.

Edwin I. Hatch Nuclear Plant, Units 1 & 2 cc:

Laurence Bergen Oglethorpe Power Corporation 2100 E. Exchange Place P.O. Box 1349 Tucker, GA 30085-1349 Mr. R. D. Baker Manager - Licensing Southern Nuclear Operating Company, Inc.

P.O. Box 1295 Birmingham, AL 35201-1295 Resident Inspector Plant Hatch 11030 Hatch Parkway N.

Baxley, GA 31531 Harold Reheis, Director Department of Natural Resources 205 Butler Street, SE., Suite 1252 Atlanta, GA 30334 Steven M. Jackson Senior Engineer - Power Supply Municipal Electric Authority of Georgia 1470 Riveredge Parkway, NW Atlanta, GA 30328-4684 Mr. Reece McAlister Executive Secretary Georgia Public Service Commission 244 Washington St., SW Atlanta, GA 30334 Arthur H. Domby, Esq.

Troutman Sanders Nations Bank Plaza 600 Peachtree St, NE, Suite 5200 Atlanta, GA 30308-2216 Chairman Appling County Commissioners County Courthouse Baxley, GA 31513 Mr. Jeffrey T. Gasser Executive Vice President Southern Nuclear Operating Company, Inc.

P.O. Box 1295 Birmingham, AL 35201-1295 General Manager Edwin I. Hatch Nuclear Plant Southern Nuclear Operating Company, Inc.

U.S. Highway 1 North P.O. Box 2010 Baxley, GA 31515 Mr. K. Rosanski Resident Manager Oglethorpe Power Corporation Edwin I. Hatch Nuclear Plant P.O. Box 2010 Baxley, GA 31515