ML052700285
| ML052700285 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 09/26/2005 |
| From: | Cowan P AmerGen Energy Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 5928-05-20269, BL-03-001 | |
| Download: ML052700285 (4) | |
Text
10 CFR 50.54(f) 5928-05-20269 September 26,2005 US. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Three Mile Island, Unit 1 (TMI Unit 1)
Facility Operating License No. DPR-50 NRC Docket No. 50-289
Subject:
Response To Request For Additional Information -
Bulletin 2003-01, Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors
References:
(1) NRC Bulletin 2003-01, Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors (2) Letter from P. B. Cowan (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, dated August 18, 2005 (3) Email from P. S. Tam (U.S. Nuclear Regulatory Commission) to D. H. Walker (AmerGen Energy Company, LLC), dated September 1 1,2005 This letter provides additional information regarding Three Mile Island (TMI) Unit 1s response to NRC Bulletin 2003-01, Potential Impact of Debris Blockage on Emergency Sump Recirculation at Pressurized-Water Reactors. Specifically, the additional information is provided in response to the Reference (3) email that requested AmerGen Energy Company, LLC provide details on Candidate Operator Action (COA) 6, Inject More Than One RWST (BWST) Volume From a Refilled RWST (BWST) or by Bypassing the RWST (BWST). The COA is defined in Westinghouse Owners Group guidance WCAP-16204, Revision 1, Evaluation of Potential ERG and EPG Changes to Address NRC Bulletin 2003-01 Recommendations, dated March 2004.
TMI-1 has revised its Emergency Procedures to establish Borated Water Storage Tank (BWST) refill upon completion of the Emergency Core Cooling System (ECCS) pump suction switchover to the Reactor Building (RB) sump, and to have the Technical Support Center (TSC) review its written guideline for reinitiating injection from the
U.S. Nuclear Regulatory Commission September 26,2005 Page 2 BWST. Specific direction will be developed based on the conditions of the scenario.
TMI has existing procedures for refilling the BWST from the spent fuel pool and from the condensate storage tanks. If the ECCS sump screen becomes totally blocked, the desired long-term Reactor Coolant System (RCS) injectionkooling mode is for the Low Pressure Injection (LPI) pumps to draw from the BWST. If this cannot be achieved, or until this can be achieved, an alternate injection path can be made available using lower capacity pumps.
The TSC written guideline currently being developed will recommend using a normal Makeup (MU)/RCS fill capability having other transfer pumps draw from one of the reactor coolant bleed tanks and inject through the MU system to the RCS. If RCS pressure is too great to allow adequate injection flow, the TSC written guideline will include the option of using the transfer pumps to supply the MU tank (Volume Control Tank) and then align a High Pressure Injection (HPI) pump to inject into the RCS.
AmerGen intends to include this additional guidance in the written guideline previously committed to per the Reference (2) letter. As a result of the additional scope to the previous commitment, the new commitment date for this action will be October 31, 2005.
There are no new regulatory commitments established by this submittal; however, an existing commitment has been revised and is provided as Enclosure 1. The revised commitment acknowledges that alternate RCS makeup capabilities will be identified in the previously committed TSC written guideline.
If any additional information is needed, please contact Doug Walker at (610) 765-5726.
I declare under penalty of perjury that the foregoing is true and correct.
Very truly yours, Executed On Pamela B. Cowan Director, Licensing and Regulatory Affairs AmerGen Energy Company, LLC
Enclosure:
1 ) List of Additional Commitments cc:
S. J. Collins, USNRC, Administrator, Region I P. S. Tam, USNRC, Senior Project Manager, TMI Unit 1 D. M. Kern, USNRC, Senior Resident Inspector, TMI Unit 1 File No. 05049
ENCLOSURE 1 LIST OF ADDITIONAL COMMITMENTS
SUMMARY
OF EXELON / AMERGEN ~O~MITMENTS THREE MILE ISLAND NUCLEAR STATION, UNIT 1 The following table identifies commitments made in this document by Exelon/AmerGen.
(Any other actions discussed in the submittal represent intended or planned actions.
They are described to the NRC for the NRCs information and are not regulatory commitments.)
COMMITTED COMMITMENT In response to Generic Letter 2003-01, TMI Engineering will develop a TSC written guideline that will cover re-injecting additional inventory following a loss of coolant accident. This will include guidance for injecting more than one BWST volume from a refilled BWST and injecting from alternate water sources.
October 31,2005