ML20216D804
| ML20216D804 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom, Limerick  |
| Issue date: | 07/19/1999 |
| From: | Hutton J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEIN-96-007, NUDOCS 9907300112 | |
| Download: ML20216D804 (2) | |
Text
,
Ctation Support Department a
v PECO NUCLEAR-esco ceer9, comgee, 965 Chesterbrook Boulevard A Unit of PECO Energy wayre. PA 19087-5691 July 19,1999 Docket Nos. 50-277 50-278 50-352 50-353 License Nos. DPR-44 DPR-56 NPF-39 NPF-85 U. S. Nuclear Regulatory Commission Attn: Do::ument Control Desk Washington, DC 20555
Subject:
Summary of Final PECO Nuclear Actions Taken to Resolve Scram Solenoid Pilot Valve issues identified in information Notice 96-07
Reference:
1.
NRC Information Notice 96-07," Slow Five Percent Scram insertion Times Caused by Viton Diaphragms in Scram Solenoid Pilot Valves," January 26, 1996.
2.
Letter, BWR Owners' Group Scram Solenoid Pilot Valve Committee Project Manager to BWR Owners' Group Primary Representatives and to BWR Owners' Group Scram Solenoid Pilot Valve Committee Members,
" Recommendations for Utility Actions for Resolution of the Dual ASCO Scram Solenoid Pilot Valve issue,' February 5,1997.
3.
Letter, BWR Owners' Group Scram Solenoid Pilot Valve Committee Project Manager to BWR Owners' Group Primary Representatives and to BWR i
Owners' Group Scram Solenoid Pilot Valve Committee Members. *NRC Acceptance of SSPV Committee Submittal," April 25,1997.
Dear Sir / Madam:
- Reference 1 alerted Boiling Water Reactor operators to slow five percent scram insertion times associated with fluoroelastomeric (Viton) diaphragms used in scram solenoid pilot valves (SSPVs). At that time, based on the Reference 1 guidance, PECO Nuclear instituted a program of increased frequency scram time testing of control rods with Viton SSPVs in order to gather data and to trend scram times. This data has been evaluated in accordance with the guidance provided in Reference 2. In over two and one-half years of testing, none of the four PECO Nuclear-operated units (Peach Bottom Atomic Power Station Units 2 and 3, Limerick Generating Station Units 1 and 2) has experienced a degradation of Viton SSPV control rod five percent scram insertion time. Additionally, substantial margin to the Technical Specification limit for five percent scram insertion time has consistently been found to exist during the increased frequency testing. Therefore, based on the Reference 3 guidance, PECO Nuclear intends to conclude its program of increased frequency scram time testing of control rods with Viton SSPVs. PECO h
Nuclear will continue to monitor Viton SSPV performance during normally scheduled (120 day
' Technical Specification surveillance) scram time testing.
Very truly yours, ames A. Hutton Director-Licensing 9907300112 990719 PDR ADOCK 05000277
' G PDR
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July 19,1999 Page 2 cc:
H. J. Miller, Administrator, Region I, USNRC A. L. Bunitt, USNRC Senior Resident inspector, LGS A. C. McMurtray, USNRC Senior Resident inspedor, PSAPS c
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