ML17059A241
| ML17059A241 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 03/21/1994 |
| From: | Brinkman D Office of Nuclear Reactor Regulation |
| To: | Sylvia B NIAGARA MOHAWK POWER CORP. |
| References | |
| NUDOCS 9403250195 | |
| Download: ML17059A241 (4) | |
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Docket No. 50-220 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, O.C. 20555-000I March 21, 1994 Mr. B. Ralph Sylvia Executive Vice President, Nuclear Niagara Mohawk Power Corporation
- 30) Plainfield Road
- Syracuse, New York 13212
Dear Mr. Sylvia:
SUBJECT:
SHUTDOWN COOLING SYSTEM AND CONTAINMENT SPRAY SYSTEM ISOLATION.
VALVES AT NINE MILE POINT NUCLEAR STATION UNIT NO.
1 The purpose of this letter is to inform you of the NRC staff decisions regarding proposed changes in the methods for sealing the shutdown cooling system and containment spray system isolation valves.
During a meeting with NRC staff members on February 22,
- 1994, members of your staff proposed that rather than installing the previously committed additional valves to provide containment isolation valves with Appendix J testing capabilities for the shutdown cooling system and containment spray system, these systems be permitted to continue utilizing waterseals.
The first portion of the proposal would permit the shutdown cooling system trains to depend upon single valves for isolation during cooldown from approximately 300 'F to 215 'F.
The second portion of the proposal would permit utilization of a waterseal for the containment spray system until the waterseal is lost when the containment spray pumps are deenergized in accordance with the plant's emergency operating procedures (EOPs) after the drywell pressure drops to 3.5 psig during a design basis accident.
As noted in our meeting summary (copy enclosed) for the February 22,
- 1994, meeting, the NRC staff has concluded that the plans proposed by members of your staff are feasible.
However, certain licensing actions will be required to implement the proposed plans.
Therefore, if Niagara Mohawk Power Corporation (NMPC) decides to pursue the proposed change for the shutdown cooling system rather than install the committed additional valves, NMPC will be required to submit a license amendment describing and justifying the proposed change.
This proposed license amendment should be submitted to the NRC for review within 60 days of the date of this letter to permit an orderly review and approval prior to the 1995 refueling outage.
The NRC staff has also concluded that Section III.C.3 of 10 CFR Part 50, Appendix J, requires a continuous waterseal for at least 30 days at a pressure of 1. 10 Pa for valves utilizing a waterseal.
Therefore, since the EOPs currently require deenergization of the containment spray pumps when the drywell pressure decreases to 3.5 psig, NMPC should promptly (within 60 days of the date of this letter) submit a proposed exemption pursuant to 10 CFR
- 50. 12 justifying not providing a continuous water seal for 30 days at 1. 10 Pa.
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Mr. B. Ralph Sylvia March 21, 1994 This exemption is required for the current condition and will be required if NMPC decides to pursue the proposed change in commitment.
Please feel free to contact me on (301) 504-1409 if you have any questions regarding these matters.
Sincerely, 9 ~Jg.d Donald S.
Brinkman, Senior Project Manager Project Directorate I-1'ivision of Reactor Projects - I/II Office of Nuclear Reactor Regulation
Enclosure:
February 22, 1994 Meeting Summary w/o enclosures cc w/enclosure:
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