ML17059B176
| ML17059B176 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 06/24/1996 |
| From: | Hood D NRC (Affiliation Not Assigned) |
| To: | Sylvia B NIAGARA MOHAWK POWER CORP. |
| References | |
| NUDOCS 9606280169 | |
| Download: ML17059B176 (6) | |
Text
,~~r.
B. Ralph Sylvia Executive Vice PresideI v,
and Chief Nuclear Officer Niagara Mohawk Power Corporation Generation Business Group D-2 300 Erie Boulevard West
- Syracuse, NY 13202 June 24, 1996
SUBJECT:
STAFF REVIEW OF MODIFICATIONS TO REVISION 4 OF THE BOILING WATER REACTOR (BWR)
EMERGENCY PROCEDURE GUIDELINES
Dear Hr. Sylvia:
The NRC staff has issued its safety evaluation (SE) on the recent Boiling Water Reactor Owners Group proposed modifications to the BWR Emergency Procedure Guidelines.
The staff is providing this information to ensure that licensees are aware of the conclusions of the staff's review.
Both the staff and the Advisory Committee for Reactor Safeguards (ACRS) agree that, for BWRs injecting standby liquid control through a standpipe below the core, maintenance of level above top-of-active fuel (TAF) is the superior water control strategy in an anticipated transient without scram (ATWS) event.
The staff recommends a level around TAF +5 feet (1.52 m), or as high as possible while still maintaining the level at least 2 feet (0.61 m) below the feedwater sparger.
Although control at any level between the minimum steam cooling water level and 2 feet below the feedwater sparger was found to be acceptable, both the staff and ACRS urge that a high-water-level control strategy be adopted.
Additional details are provided in the enclosed SE.
You should also note the staff's position on bypassing the Main Steam Isolation Valve (HSIV) high radiation closure interlock during ATWS.
The staff agrees with the BWROG's qualitative arguments that keeping the HSIVs open significantly reduces containment loading and makes level control much simpler.
- However, the acceptability of this change is conditional on a plant-specific evaluation by each licensee to assure that, in the event of gross fuel failures, consideration has been given to such items as equipment accessibility, potential off-site radiological doses, and the appropriate time to manually close the HSIVs.
9606280169 960624 PDR ADQCK 05000220 F
PDR Docket Nos.
50-220 and 50-410 Sincerely, ORIGINAL SIGNED BY:
Darl S.
Hood, Senior Project Manager Project Directorate I-1 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation
Enclosure:
Safety Evaluation cc w/encl:
See next page DISTRIBUTION:
Docket File SVarga SLittle ACRS PUBLIC JZwolinski DHood CCowgill, RGN-I PDI-1 Reading JHi tchel l OGC DOCUMENT NAME:
PIBWROG.LTR To receive a copy of this document, indicate in the box:
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 205M-0001 June 24, 1996 Hr. B. Ralph Sylvia Executive Vice President and Chief Nuclear Officer Niagara Hohawk Power Corporation Generation Business Group D-2 300 Erie Boulevard West
- Syracuse, NY 13202
SUBJECT:
STAFF REVIEW OF HODIFICATIONS TO REVISION 4 OF THE BOILING WATER REACTOR (BWR)
EHERGENCY PROCEDURE GUIDELINES
Dear Hr. Sylvia:
The NRC staff has issued its safety evaluation (SE) on the recent Boiling Water Reactor Owners Group proposed modifications to the BWR Emergency Procedure Guidelines.
The staff is providing this information to ensure that licensees are aware of the conclusions of the staff's review.
Both the staff and the Advisory Committee for Reactor Safeguards (ACRS) agree that, for BWRs injecting standby liquid control through a standpipe below the core, maintenance of level above top-of-active fuel (TAF) is the superior water control strategy in an anticipated transient without scram (ATWS) event.
The staff recommends a level around TAF +5 feet (1.52 m), or as high as possible while still maintaining the level at least 2 feet (0.61 m) below the feedwater sparger.
Although control at any level between the minimum steam cooling water level and 2 feet below the feedwater sparger was, found to be acceptable, both the staff and ACRS urge that a high-water-level control strategy be adopted.
Additional details are provided in the enclosed SE.
You should also note the staff's position on bypassing the Hain Steam Isolation Valve (HSIV) high radiation closure interlock during ATWS.
The staff agrees with the BWROG's qualitative arguments that keeping the HSIVs open significantly reduces containment loading and makes level control much simpler.
However, the acceptability of this change is conditional on a plant-specific evaluation by each licensee to assure that, in the event of gross fuel failures, consideration has been given to such items as equipment accessibility, potential off-site radiological
- doses, and the appropriate time to manually close the HSIVs.
Sincerely,
$)~g/~
Darl S.
Hood, Senior Project Hanager Project Directorate I-1 Division of Reactor Projects I/II Office of Nuclear Reactor Regulation Docket Nos.
50-220 and 50-410
Enclosure:
Safety Evaluation cc w/encl:
See next page
f
B. Ralph Sylvia Niagara Mohawk Power Corporation Nine Mile Point Nuclear Station Unit Nos.
1 and 2
CC:
Mr. Richard B. Abbott Vice President and General Hanager-Nuclear Niagara Hohawk Power Corporation Nine Mile Point Nuclear Station P.O.
Box 63
- Lycoming, NY 13093 Hr. Martin J.
HcCormick, Jr.
Vice President Nuclear Safety Assessment and Support Niagara Mohawk Power Corporation
. Nine Mile Point Nuclear Station P.O.
Box 63
- Lycoming, NY 13093 Ms. Denise J. Wolniak Manager Licensing Niagara Mohawk Power Corporation Nine Mile Point Nuclear Station P.O.
Box 63
- Lycoming, NY 13093 Hr. Kim A. Dahlberg General Manager - Projects Niagara Mohawk Power Corporation Nine Mile Point Nuclear Station P.O.
Box 63
- Lycoming, NY 13093 Hr. Norman L. Rademacher Plant Manager, Unit 1
Nine Mile Point Nuclear Station P.O.
Box 63
- Lycoming, NY 13093 Hr. John T. Conway Plant Manager, Unit 2 Nine Mile Point Nuclear Station P.O.
Box 63
- Lycoming, NY 13093 Regional Administrator, Region I U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Resident Inspector U. S. Nuclear Regulatory Commission P.O.
Box 126
- Lycoming, NY 13093 Charles Donaldson, Esquire Assistant Attorney General New York Department of Law 120 Broadway New York, NY 10271 Hr. Paul D.
Eddy State of New York Department of Public Service Power Division, System Operations 3 Empire State Plaza
- Albany, NY 12223 Hr. Richard H. Kessel Chair and Executive Director State Consumer Protection Board 99 Washington Avenue
- Albany, NY 12210 Hark J. Wetterhahn, Esquire Winston
& Strawn 1400 L Street, NW Washington, DC 20005-3502 Gary D. Wilson, Esquire Niagara Mohawk Power Corporation 300 Erie Boulevard West
- Syracuse, NY 13202 Hr. F. William Valentino, President New York State
- Energy, Research, and Development Authority 2 Rockefeller Plaza
- Albany, NY 12223-1253 Supervisor Town of Scriba Route 8, Box 382
- Oswego, NY 13126 Hr. Richard Goldsmith Syracuse University College of Law E. I. White Hall Campus
- Syracuse, NY 12223 Hr. John V. Vinquist, MATS Inc.
P.O.
Box 63
- Lycoming, NY 13093