ML18047A304
| ML18047A304 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 04/26/1982 |
| From: | Johnson B CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| REF-SSINS-6820 IEB-80-04, IEB-80-4, NUDOCS 8204300419 | |
| Download: ML18047A304 (2) | |
Text
consumers Power company General Offices: 1945 West Parnall Road, Jackson, Ml 49201 * (517) 788-0550 April 26, 1982 Dennis M Crutchfield, Chief Operating Reactors Branch No 5 Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-255 -
LICENSE DPR-20 PALISADES PLANT - RESPONSE TO IE BULLETIN 80-04 ADDITIONAL INFORMATION IE Bulletin 80-04 requested Consumers Power Company to review the containment pressure response following a Main Steam Line Break (MSLB) inside containment to determine the potential for containment overpressurization due to runout flows of the Auxilary Feedwater (AFW), Condensate and Main Feedwater (MFW) pumps.
Consumers Power Company response, dated May 9, 1980, addressed runout flow of the AFW pumps and stated that the runout flows from the conden-sate and.MFW pumps would be addressed in LER 79-041.
NRC letter dated March 8, 1982 requested additional information with regards to condensate and.MFW pump runout flows.
Presented below is a discussion of LER 79-041 and the modification made at Palisades which addresses request identified in the March 8, 1982 NRC letter.
Following a MSLB the.MFW pumps are designed to ramp down in flow in order to minimize the water added to the ruptured steam generator.
However, if offsite power is still available the condensate pumps can continue to pump water through the MFW pumps into the ruptured steam generator.
This was identified as a design deficiency and reported in LER 79-041.
As a result, the control circuitry of the feedwater regulating valves (CV-0701 and CV-0703) and feedwater bypass valves (CV-0734 and CV-0735) was modified so as to close the valves on steam generator low pressure.
Since the regulating valves and the bypass valves are downstream of both the condensate pumps and MFW pumps, this modification assures that flow to the ruptured steam generator will be less than that assumed in the safety analysis.
DMCrutchfield, Chief Palisades Plant Response to IE Bulletin 80-04, Additional Information April 26, 1982 The steam generator low pressure signal used to close the valves is the same as that used to trip the Main Steam Isolation Valves (MSIV's) and thus providing the same 2/4 logic.
Also, the components of the feedwater regulating and bypass valves circuitry are Q-listed thereby assuring they will operate in accident conditions.
Brian D Johnson Senior Licensing Engineer CC Administrator. Region III. USNRC NRC Resident Inspector - Palisades 2