IR 05000255/1989009

Provides Update on Status of Testing,Mods & Design Reviews for Plant Emergency Escape Airlock,As Followup to Util 910729,890630 & 0522 Responses to Proposed NOV in NRC Insp Rept 50-255/89-09,dtd 890421

ML18064A619
Person / Time
Site:	Palisades
Issue date:	02/10/1995
From:	HAAS K M CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9502230233
Download: ML18064A619 (4)

Text

. * * consumers Power POWERING Mli:Hl&AN"S l'RO&RESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 February 10, 1995 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 -LICENSE DPR-20 -PALISADES PLANT -KurtM. Haas Plant Safety and Licensing Director REQUEST FOR RELIEF FROM lOCFR50 APPENDIX J PRESSURE TESTING ON THE EMERGENCY ESCAPE AIRLOCK DOORS The purpose of this letter is to provide an update on the status of testing, modifications, and design reviews for the Palisades emergency escape airlock. This letter is a follow up to CPCo letters dated July 29, 1991, June 30, 1989, and May 22,1989, which provided responses to a proposed Notice Of Violation in NRC Inspection Report 89-009, dated April 21, 1989. As a result of this review, we request that the NRC use the information provided herein as the basis for a request for relief from the pressure testing requirement imposed by 10CFR50, Appendix J, Section III, D.2.(b)(ii)

and (iii) for the emergency escape airlock. These Appendix J sections require pressure testing an airlock after any opening of the airlock. Paragraph (ii) applies to periods when containment integrity is not required and paragraph (iii) applies to periods when containment integrity is require The relief request is necessary due to the emergency escape airlock door design which requires the doors to be opened after full pressure testing or after between the door seals testing. The doors must be opened to remove door holddown clamps and to inspect and adjust the door seals to correct the adverse effects from the door clamping forces. Further details of the inability to test the escape lock per the Appendix J requirements are provided in the CPCo letters dated May 22, 1989 and June 30, 1989, which are also . included as Attachments 1 and 2 to this letter. The CPCo letters were recently reviewed and still contain accurate information pertaining to the design and testing of the emergency escape airlock . 'CJj (/"!! Ai Ip' ;;.,, .! u: Q L:k 950210 05000255 PDR A CMS' ENERGY COMPANY

• 2 An alternative for verification of door seal functionality is to continue with the present successful procedural practice of ensuring proper door seals contact prior to final door closure. This seal performance verification is completed after the removal of the door holddown clamps, following the full pressure airlock test, and just prior to final closure of the airlock doors. The performance of the door seal contact check has led to the successful completion of subsequent semi-annual escape lock full pressure tests since the procedural practice began in 1987. Recent as-found test results are included as Attachment 3. The present methods verify the design function capability of the escape lock door seals and provide proper protection for public health and safety. A major modification to the escape lock would allow Appendix J testing to be completed as presently required, however it would only provide the same level of protection for public health and safety as currently exists. Attachments 1 and 2 also contain further details regarding this successful alternative method. In the most recent letter on this issue, dated July, 29,1991, we informed the NRG that we would perform additional low pressure between the seals testing on the escape lock door seals, and also investigate modifications to the existing emergency escape airlock doors to facilitate between the seals testing. Special Test T-317, "Escape Air Lock Between the Seals Test", was completed on March 20, 1992, to measure seal leak rates at low initial pressures and without the door clamps installe The trial tests were performed at pressures lower than the Palisades Technical Specification test pressure requirements of 10 psig. The test results indicate that meaningful between the seals testing is not possible with the present design of the escape air lock. The annulus between the door seals was pressurized to as low as 2 psig and without the door clamps installed the test pressure dropped off immediatel This indicates that the leak rates for between the seals testing on the emergency escape airlock can not be properly measured or evaluated against meaningful acceptance criteria if the door clamps are not installe Since that time we have also evaluated possible modifications to the escape lock to facilitate between the seals testing. The only viable alternative is the replacement of the air lock doors which has been estimated to cost a minimum of $ 700,000. The cost of performing the modification is not warranted because no increase in plant or public safety would be realize Other minor modifications to the present doors or seals were considered, but no other options would provide adequate performance improvement for between the seals testing. Request for Relief Based on the foregoing discussion, Palisades seeks relief from the 10 CFR 50, Appendix J, Section III, subsection D.2(b)(ii)

and (iii) requirement to perform pressure testing on the emergency escape airlock doors after each door opening. The following alternative approach will be used to provide proper verification of door seals design basis functionality:

• * Per the present requirements, the semi-annual full pressure air lock test will be completed at the proper time intervals and at any plant mode. After successful testing, the doors will be opened as necessary to remove door holddown clamps while preserving containment integrity (if required).

Prior to final closure of each door, the seal contact verification will be completed on the door seals. This seal contact check will replace the pressure test required by Appendix J for this door opening associated with restoration from the test. Any subsequent opening of an escape lock door that is not associated with the restoration activities from a full pressure test will require a full airlock pressure test within the 72-hour time period described in Appendix J. Kurt M. Haas Plant Safety and Licensing Director CC Administrator, Region III, USNRC NRC Resident Inspector

-Palisades Attachment 3

• ATTACHMENT 1 Consumers Power Company Palisades Plant Docket 50-255 CPCO LETTER DATED MAY 22, 1989 REGARDING ESCAPE AIRLOCK TESTING 4 Pages