ML18057A331

Proposed Tech Spec Pages Re Over Pressure Protection Sys

ML18057A331
Person / Time
Site:	Palisades
Issue date:	07/11/1990
From:	Hoffman D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML18057A330	List: ML18057A329 ML18057A331 ML18057A332
References
NUDOCS 9007170154
Download: ML18057A331 (3)

Text

2 CONSUMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 For the reasons hereinafter set forth, it is requested that the Technical Specifications contained in the Provisional Operating License DPR-20, Docket 50-255, issued to Consumers Power Company on October 16, 1972, for the Palisades Plant be changed as described in Section I below:

I. Changes A. Change Specification 4.1.1, a.4 to read as follows:

"4. Testing in accordance with the Inservice Inspection requirements for Section XI, Subsection !WV, for Category B valves."

II. Discussion Palisades technical specification 4.1.1, a.4 currently requires that each PORV be tested in accordance with the.inservice inspection requirements for category C valves as defined in the 1983 ASME Boiler and Pressure Vessel Code,Section XI. Category C valves are defined in code article IWV-2200, as " ... valves which are self-actuating in response to some system characteristic, such as pressure (relief valves) or flow direction (check valves)." The PORV' s at the Palisades Plant were originally defined as Category C valves based on their function as pressure relief valves and were tested as required by article IWV-3500. However, based on an engineering review of the inservice testing requirements of plant systems, it was determined that the classification of the PORV' s as category C valves was technically incorrect in that they are actuated via an external signal rather than being self-actuating as defined by the ASME code. Based on our evaluation, Consumers Power Company believes that the Palisades PORV's should be classified as category B valves and tested in accordance with the requirements of ASME Boiler and Pressure Vessel Code,Section XI, subsection !WV, paragraph IWV-3400.

Presently, both PORV' s are tested at each refueling outage.

Reclassification of the PORV's as category B valves will result in both valves being tested in accordance with the requirements of ASME Section XI. In addition, each PORV and its associated circuitry will be tested during each refueling outage. This testing schedule is significantly more conservative than the testing currently required by the plant technical specifications.

3 III. Analysis of No Significant Hazards Consideration Consumers Power Company finds that activities associated with this proposed technical specification change involve no significant hazards.

The following evaluation supports that finding.

1. 'Will the proposed change involve a significant increase . in the probability or consequences of an accident previously evaluated.

No. The proposed change affects only the required inservice testing schedule for the PORV's.

Currently, both PORV' s are tested at each refueling outage. The change in ASME category of the PORV's from C to B will result in each PORV being stroked tested using the valve solenoid once each quarter if the Primary Coolant System (PCS) has been placed in cold shutdown and depressurized.

In addition, each PORV and its actuating circuit will be tested during each refueling outage in accordance with Plant surveillance procedure requirements. This testing schedule is more conservative than currently required thus, the probability or consequences of an accident previously evaluated are not increased.

2. 'Will the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated.

No. The proposed change will affect only the testing schedule of the PORV's.

The PORV's are part of the overpressure protection system for the PCS.

The overpressure protection system is designed to protect against overpressure events such as the inadvertent initiation of high pressure safety injection, the starting of a charging pump, or an uncontrolled heatup of the PCS during shutdown cooling. Because testing of the PORV's and their associated circuitry will be done when the PCS is at cold shutdown and depressurized, the safety function of the overpressure protection system is not compromised. In addition, during the testing of the PORV's, alternate vent paths are available to the operator should it be necessary to prevent or relieve a PCS pressure buildup. The paths include the reactor head vent system, the pressurizer manway, or manual actuation of the PORV.

3. 'Will the proposed change involve a significant reduction in the margin of safety.

No. The margin of safety as defined in the basis statements for Plant Technical Specifications and the Palisades Updated Final Safety Analysis Report (UFSAR) will not be reduced.

Testing of the PORV's and their associated circuitry will occur only with the PCS in cold shutdown and dep~essurized. Testing of the PORV's as

4 Category B valves will be performed within the requirements of Technical Specification 3.1.8, "Overpressure Protection Systems" which establishes the minimum operability requirements for the overpressure protection system. In addition, testing of the PORV' s each quarter and each refueling is more conservative than currently required.

IV. Conclusion The Palisades Plant Review Committee has reviewed this Technical Specification Change Request and has determined that this change does not involve an unreviewed safety question and, therefore, involves no significant hazards consideration. This change has been reviewed by the Nuclear Safety Services Department.- A copy of this Technical Specification Change Request has been sent to the State of Michigan official designated to receive such Amendments to the Operating License.

CONSUMERS POWER COMPANY To the best of my knowledge, information and belief, the contents of this Technical Specification Change Request are truthful .and complete.

By David P Hoffman, Vice Nuclear Operations Sworn.and subscribed to before me this _/f_th day of~ 1990.

Elaine E Buehrer, Notary Public Jackson County, Michigan My commission expires October 11, 1993