ML051100012

RAI, Elimination of Containment Equipment Hatch Closure During Refueling

ML051100012
Person / Time
Site:	Three Mile Island
Issue date:	05/02/2005
From:	Colburn T NRC/NRR/DLPM/LPD1
To:	Crane C AmerGen Energy Co
Colburn T, NRR/DLPM, 415-1402
References
TAC MC4904
Download: ML051100012 (6)

Text

May 2, 2005 Mr. Christopher M. Crane President and Chief Executive Officer AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION (RAI) RE: THREE MILE ISLAND NUCLEAR STATION, UNIT 1 (TMI-1) ELIMINATION OF CONTAINMENT EQUIPMENT HATCH CLOSURE DURING REFUELING (TAC NO. MC4904)

Dear Mr. Crane:

By letter dated October 20, 2004, AmerGen Energy Company, LLC (the licensee), submitted a license amendment request to eliminate the containment equipment hatch closure requirement during fuel loading and refueling operations for TMI-1.

The Nuclear Regulatory Commission staff has determined that it will need the additional information identified in the enclosure to this letter in order to complete its review of the request.

As discussed with and agreed to by your staff, please provide the requested information within 30 days of receipt of this letter. If you have any questions, please contact me at (301) 415-1402.

Sincerely,

/RA/

Timothy G. Colburn, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosure:

RAI cc w/encl: See next page

May 2, 2005 Mr. Christopher M. Crane President and Chief Executive Officer AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION (RAI) RE: THREE MILE ISLAND NUCLEAR STATION, UNIT 1 (TMI-1) ELIMINATION OF CONTAINMENT EQUIPMENT HATCH CLOSURE DURING REFUELING (TAC NO. MC4904)

Dear Mr. Crane:

By letter dated October 20, 2004, AmerGen Energy Company, LLC (the licensee), submitted a license amendment request to eliminate the containment equipment hatch closure requirement during fuel loading and refueling operations for TMI-1.

The Nuclear Regulatory Commission staff has determined that it will need the additional information identified in the enclosure to this letter in order to complete its review of the request.

As discussed with and agreed to by your staff, please provide the requested information within 30 days of receipt of this letter. If you have any questions, please contact me at (301) 415-1402.

Sincerely,

/RA/

Timothy G. Colburn, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosure:

RAI cc w/encl: See next page DISTRIBUTION PUBLIC PDI-1 R/F RLaufer TColburn DLPM/DPR MOBrien BHarvey ADrodz OGC ACRS ABurritt, RGN-I ACCESSION NO.: ML051100012 OFFICE PDI-1\PM PDI-2\LA SPSB\SC(A) PDI-1\SC NAME TColburn MOBrien SLittle for ADrodz RLaufer DATE 4/28/05 04/26/05 04/27/05 4/29/05 OFFICIAL RECORD COPY

REQUEST FOR ADDITIONAL INFORMATION ELIMINATION OF CONTAINMENT EQUIPMENT HATCH CLOSURE REQUIREMENT DURING FUEL MOVEMENT AND REFUELING OPERATIONS THREE MILE ISLAND NUCLEAR STATION, UNIT 1 (TMI-1)

DOCKET NO. 50-289 By letter dated October 20, 2004, AmerGen Energy Company, LLC (AmerGen or the licensee),

requested a license amendment for TMI-1 to allow elimination of the containment equipment hatch closure requirement during fuel movement and refueling operations. The Nuclear Regulatory Commission (NRC) previously issued License Amendment No. 215 for TMI-1 on August 24, 1999, which allowed increases in allowable leakage for applicable portions of the engineered safety features systems located outside containment and clarified the system design requirements for the auxiliary and fuel-handling building ventilation system. License Amendment No. 236 was issued for TMI-1 on October 2, 2001, allowing personnel and emergency air locks to remain open during fuel movement and refueling operations but requiring the licensee to be able to achieve containment closure within 45 minutes following a fuel-handling accident (FHA). The licensees basis for the October 20, 2004, license amendment request is the previously reviewed and approved limiting design basis analysis of the TMI-1 FHA inside the reactor building as documented in Amendment No. 236. The FHA radiological consequence analysis for Amendment No. 236 uses containment-leakage/yard-intake control room atmospheric dispersion factors (/Q values) which were reviewed by the NRC staff during the review of Amendment No. 215. The safety evaluation enclosed with Amendment No. 215 states, in part:

The staff finds the /Q values calculated by the licensee to be acceptable for use in the dose assessment for the Cycle 13 operating cycle. The NRC is attempting to resolve control room issues generically through an industry forum and the staff may reassess the control room /Q values proposed by the licensee in this license amendment request, if needed, based on conclusions drawn from resolution of the control room generic issues.

As part of the ongoing resolution of the control room generic issues, the NRC staff issued Regulatory Guide (RG) 1.194, Atmospheric Relative Concentrations for Control Room Radiological Habitability Assessments at Nuclear Power Plants, in June 2003. This RG describes methods currently acceptable to the NRC staff for determining /Q values for use in control room radiological habitability assessments. The RG states that licensees can continue to use /Q values determined with methodologies previously approved by the NRC staff if these values are appropriate for the application in which they are being used.

The FHA radiological consequence analysis for Amendment No. 236 assumes that the reactor building purge system is in operation. Consequently, any leakage through the personnel and emergency air locks would be from the environment into the reactor building because the purge system would be maintaining the reactor building at a negative pressure. Any FHA activity would be released to the environment through the unit vent without filtration by the reactor

Enclosure building purge air treatment system. If the purge system were to become inoperable, releases could occur through the open personnel and emergency air lock doors (and, if the licensees October 20, 2004, license amendment request were implemented through the open equipment hatch).

1. The FHA radiological consequence analysis for Amendment No. 236 uses /Q values that were derived assuming a diffuse source release from the reactor building; i.e., the activity being released is assumed to be homogeneously distributed throughout the reactor building and leak over the entire reactor building surface. In reality, the releases are likely to occur through the unit vent or through an open personnel, equipment, and/or emergency hatch. Please confirm that the diffuse source control room /Q values used in the Amendment No. 236 dose assessment bound the atmospheric dispersion characteristics for releases from the unit vent, personnel hatch, equipment hatch, and emergency air lock.

2. The FHA radiological consequence analysis for Amendment No. 236 uses /Q values that were derived assuming all infiltration into the control room (both filtered and unfiltered) occurs through the control room yard air intake. Using the results of the tracer gas testing performed on the TMI-1 control room envelope, please confirm that there are no potential unfiltered inleakage pathways during the control room isolation mode that could result in /Q values that are higher that the control room yard air intake

/Q values.

Three Mile Island Nuclear Station, Unit 1 cc:

Site Vice President - Three Mile Island Nuclear Director - Licensing and Regulatory Affairs Station, Unit 1 AmerGen Energy Company, LLC AmerGen Energy Company, LLC 200 Exelon Way, KSA 3-E P. O. Box 480 Kennett Square, PA 19348 Middletown, PA 17057 Rich Janati, Chief Senior Vice President - Nuclear Services Division of Nuclear Safety AmerGen Energy Company, LLC Bureau of Radiation Protection 4300 Winfield Road Department of Environmental Protection Warrenville, IL 60555 Rachel Carson State Office Building P.O. Box 8469 Vice President - Operations, Mid-Atlantic Harrisburg, PA 17105-8469 AmerGen Energy Company, LLC 200 Exelon Way, KSA 3-N Plant Manager - Three Mile Island Nuclear Kennett Square, PA 19348 Station, Unit 1 AmerGen Energy Company, LLC Vice President - Licensing and Regulatory Affairs P. O. Box 480 AmerGen Energy Company, LLC Middletown, PA 17057 4300 Winfield Road Warrenville, IL 60555 Regulatory Assurance Manager - Three Mile Island Nuclear Station, Unit 1 Regional Administrator AmerGen Energy Company, LLC Region I P.O. Box 480 U.S. Nuclear Regulatory Commission Middletown, PA 17057 475 Allendale Road King of Prussia, PA 19406 Peter Eselgroth, Region I U.S. Nuclear Regulatory Commission Chairman 475 Allendale Road Board of County Commissioners King of Prussia, PA 19406 of Dauphin County Dauphin County Courthouse Michael A. Schoppman Harrisburg, PA 17120 Framatome ANP Suite 705 Chairman 1911 North Ft. Myer Drive Board of Supervisors Rosslyn, VA 22209 of Londonderry Township R.D. #1, Geyers Church Road Vice President, General Counsel and Secretary Middletown, PA 17057 AmerGen Energy Company, LLC 2301 Market Street, S23-1 Senior Resident Inspector (TMI-1) Philadelphia, PA 19101 U.S. Nuclear Regulatory Commission P.O. Box 219 Middletown, PA 17057

Three Mile Island Nuclear Station, Unit 1 cc:

Dr. Judith Johnsrud National Energy Committee Sierra Club 433 Orlando Avenue State College, PA 16803 Eric Epstein TMI Alert 4100 Hillsdale Road Harrisburg, PA 17112 Correspondence Control Desk AmerGen Energy Company, LLC P.O. Box 160 Kennett Square, PA 19348 Manager Licensing - Three Mile Island Nuclear Station, Unit 1 Exelon Generation Company, LLC 200 Exelon Way, KSA 3-E Kennett Square, PA 19348 Associate General Counsel AmerGen Energy Company, LLC 4300 Winfield Road Warrenville, IL 60555