ML18058A506
| ML18058A506 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 06/05/1992 |
| From: | Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9206150440 | |
| Download: ML18058A506 (2) | |
Text
consumers Power POW ERIN&
MICHlliAN"S PROliRESS Palisades Nuclear Plant:
27780 Blue Star Memorial Highway, Covert, Ml 49043 June 5, 1992 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 GB Slade General Manager DOCKET 50-255 - LICENSE DPR PALISADES PLANT - CORRECTION TO INFORMATION REGARDING THE DURATION OF THE POWER SUPPLY TO THE CRITICAL FUNCTIONS MONITORING SYSTEM FOLLOWING A LOSS OF OFFSITE POWER In Consumers Power Company's letter dated November 27, 1991, our commitment to provide a diesel-backed power supply to our critical functions monitor (CFMS)
(safety parameter display system) was withdrawn.
In that letter we also stated that the current design of the uninterruptible power supply (UPS) will supply power to the CFMS, and also the emergency response data system (EROS),
for greater than sixty minutes following the loss of offsite power.
We have recently determined that the actual duration capability of the UPS supply to the CFMS is one hour or less.
During the development of the design basis document (DBD) for the uninterruptible power supply (UPS), which was performed as part of the Configuration Control Project, the commitment to provide electrical power to the CFMS from a diesel-backed power supply was discovered.
We also determined that the existing load study did not reflect the loads that had been added to the UPS in recent years. Therefore, an engineering analysis was performed to determine the actual loads and the duration of the UPS supply to these loads.
The engineering analysis concluded that the UPS would supply loads for up to one hour.
This time constraint is different than the "... greater than sixty minutes... " as reported in our November 27, 1991 letter.
We have reviewed our docketed responses pertaining to the CFMS including Generic Letter 81-10 (NUREG 0737), Generic Letter 81-17 (NUREG 0696), Generic Letter 82-33 (Supplement 1 to NUREG 0737) and Generic Letter 89-06, "Task Action Plan Item I.D.2 - Safety Parameter Display System - 10 CFR §50.54(f)"
and find no specific requirement for how long the UPS must supply the CFMS.
Generic Letter 82-33, Supplement 1, Section 4.ld, states that the licensee wi 11 A CMS ENERGY COMPANY
9evel6p procedures "... which describe timely and correct safety status assessment when the SPDS is and is not available... " This statement recognizes that SPDS may become unavailable, even during an accident; however, no limitation regarding the duration of SPDS availability during an accident is established. Therefore, we conclude that our CFMS continues to satisfactorily meet the requirements for SPDS specified in NUREG 0737, Supplement 1.
Palisades has procedures in place which can be used if the CFMS is not available.
In the event that the CFMS is not available, the same data used in the CFMS is retrievable from other data sources backed up with preferred electrical power supplies. Therefore, the loss of the CFMS poses no significant decrease in the protection of the public health and safety.
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Gerald B Slade General Manager CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades