ML18058B740
| ML18058B740 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 03/29/1993 |
| From: | Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-89-04, GL-89-4, NUDOCS 9304050151 | |
| Download: ML18058B740 (4) | |
Text
consumers Power l'DWERINli MICHlliAN'S. l'RDliRESS Palisades Nuclear Plant:
27780 Blue Star M*emorial Highway, *coven, Ml 49043 March 29, 1993 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 GB Slade Gmeral Manager.
DOCKET 50-255 - LICENSE DPR PALISADES PLANT - RESPONSE TO INSPECTION REPORT 92-028, OPEN ITEM 92-028-03 NRC Inspection Report No. 92028, dated January 21, 1993, forwarded the results of the NRC inspection cqnducted from December 7 through 18, 1992.
The areas examin~d d~ring th~ inspection were primarily a review of the Palisades program for inservice testing of pumps and valves established in response to Generic Letter 89-04, and of the effectiveness of the prog~am for monitoring the performance of check valves.
The inspection report i de.nt i fi ed an open item concerning the basis for how the plants fire system provides lake water to the suction of the auxiliary feedwater pumps when other auxiliary feedwater supplies are not available. The requ~sted re~ponse to the open item is attached.
v,Y~ /-i Gerald B s1aae General Manager
- cc: Administrator, Region III, USNRC NRC Resident Inspector - Palisades Attachment 020081 9304050151 930329 PDR ADOCK*o5000255 0
PDR A CM5 ENERGY COMPANY
ATTACHMENT Consumers Power Company
_Palisades Plant Docket 50-255 RESPONSE TO INSPECTION REPORT 92028 OPEN ITEM 92028-03 March 29, 1993 2 Pages
NRC OPEN ITEM The design basis for the use of the fire water system as an
- alternative water supply and its inclusion in the TS [technical specifications] was under evaluation by the licensee.
The TS at Palisades require the fire water and service water systems to be operable and capable of providing water to the suction for the auxiliary feedwater pumps.
The EOP's at Palisades call for the 1
use of the fire water and service water systems for providing water to the steam generators when no other sources are available.
However, the licensee indicated that no credit ~as taken in the design basis for the use of the alternate supplies to mitigate the consequences of an accident.
More significantly, no analysis or testing exists to verify the capability of the fire system to provide water to the AFW system.
The licensee has initiated action to analyze the fire water system supply to the AFW system to ensure that it could be used, however the actual desigrJ basis needed to be evaluated by the licensee.
The evaluation of the design basis and inclusion of.the fire water system in the Pal.isades TS as a backup water supply to the AFW system was considered an unresolved item (50-255192028-03.(DRS)).
- ~ response to this item within 60 days of the receipt of this report was requested by the NRC inspectors.
CPCo RESPONSE
- Inspection report 92028 states that we h~d indicated no credit was taken.
in the d~sign basis for the use of the alterhate supplie~ to mitigate the consequences of an accident.
What was meant by that statement is that none of the FSAR Chapter 14 analyses s~ecifically discussed the need for the fire _water pumps as a back up water source for auxiliary feedwater, to mitigate an accident.
The fire water supply is needed to provide a back up water supply to the auxiliary feedwater pumps to mitjgate the potential damage caused by a tornado.
External events such as tornados are-not discussed as accident initiators in the Palisades FSAR Chapter 14 Safety analysis, although tornado missiles are a basis for plant design described in the FSAR (primarily Chapter 5).
A Configuration Control Project (CCP) which provides a design basis reconstitution for a number of safety.related systems is currently ongoing at Palisades: Through CCP it was identified that no readily available test report or. supporting calculation could be found showing that the fire water system pumps could provide the necessary water flows to the auxiliary feedwater pumps suction. A CCP discrepancy report was issued. The evaluation of the discrepancy report concluded that since the fire water system was the last of 6 alternate supplies to AFW-that
- the operators are directed to consider as a backup to the normal.supply, and s i nee the* fire pump head and capacity are higher than the normal water supply from the condensate storage tank, there was little likelihood of any significant design errors uncovered by this discrepancy.
As a continued follow-up to the design basis documentati-0n discrepancy, a corrective action document was written in 1992 to require that an analysis be completed to document the adequacy of the auxiliary.
- feedwater fl ow from the fire water system as part of the design basis.
A physical test to verify this design function is not practical, as we will not put untreated lake water jnto the steam generators.
2 The ability of the fire water pumps to provide a backup water supply source to the auxiliary feedwater pumps is part of the plant design basis. Credit is taken for the post tornado operability of the pumps to
- provide a source of water to the auxiliary feedwater punips.
The plant technical specifications reflect this design basis by requiring that either a service water pump or a fira system pump be available to
- support this design basis function.
The Palisades design basis *.
reconstitution program was implemented to reconfirm and provide the needed documentation to show that the plant *design basis is easily verifiable.
The lack of documented evidence which shows that the fire system pumps* can provide the required flows to the auxiliary feedwater pumps is one of the discrepancies in the plant design basis documentation which is being evaluated.
- Each fire water pump has a rated c~pacity of 1500 gpm at 313 feet of water (total dynamic head). This rating exceeds the auxiliary feedwater pump flow requi~ements of approximately 350 gpm it a lbw net positive.
suction-head. Also the length -of pipjng connecting the fire water pumps to the AFW system is short so head losses will be minimal.
Therefore, based on engirieering j~dgement we believe that the fire water pumps and interconnecting system can provide the needed water to the auxiliary feedwater pumps suction.
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