ML18054A774

Responds to Violation Noted in Insp Rept 50-255/89-09. Corrective Actions:Tech Spec Surveillance Test SO-4B, Escape Airlock Penetration, Temporarily Revised to Perform Reduced Pressure Test Between Seals

ML18054A774
Person / Time
Site:	Palisades
Issue date:	05/22/1989
From:	Berry K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 8906010201
Download: ML18054A774 (4)

Text

• • lllllCHlliAN'S PROliRESS consumern Power PllWERINli Kenneth W Berry Director Nuclear Licensing General Offices: 1945 West Parnall Road, Jackson, Ml 49201 * (517) 788-1636 May 22, 1989 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -

RESPONSE TO NOTICE OF VIOLATION PRESENTED IN IE INSPECTION REPORT 89009 NRC Inspection Report 50-255/89-009 dated April 21, 1989 transmitted one notice of violation and requested Consumers Power Company provide a written response. The requested response follows:

Notice Of Violation (255(89009-01)

• As a result of the inspection conducted on March 14 through April 10, 1989,

. and in accordance with the General Policy and Procedures of NRC Enforcement Actions (10CFR Part 2, Appendix C), the following violation was identified:

10CFR Part SO, Appendix J, III.D.2.(b) (iii) states that airlocks opened during periods when containment integrity is required by the Plant's Technical Specifications shall be tested within three days after being opened. For airlock doors having testable seals, testing the seals fulfills the three day test requirements.

Contrary to the above, the licensee failed to do a between the seal test of the escape airlock door within three days after the door was used on March 2, 1989.

Reason For Violation In the event of an .accident resulting in containment high pressure, the escape lock penetration is a potential path for the release of radioactive effluent.

This penetration is routinely tested at design pressure to demonstrate that resulting leakage is within allowable operating limits.

The escape lock design consists of an airlock barrel enclosed by two isolation doors. Each door seats against double gaskets (compression seals). Testing is accomplished by pressurizing the entire airlock volume .

• I

• .:;;*o.so 1o*-=*o 1 F_. *_,*DR OC0589-0022-NL02 A~5t~.* r

?9Q522 (J.5<J(J()2!5!~i F'DC -

Nuclear Regulatory Commission 2 Paiisades Nuclear Plant Response to IR 89-009 May 22, 1989 10CFR50 Appendix J requires testing the escape lock to assure continued integrity of the sealing surface following any opening of escape lock doors.

Testing at containment design pressure must be performed at intervals not to exceed six months. 10CFR50 Appendix J requires that Type "B" tests such as the excape lock penetration shall have a duration of not less than 15 minutes each. This test is accomplished by Technical Specification (TS) Surveillance Test S0-4B, "Escape Airlock Penetration". To perform the test, strongbacks are installed within the airlock for the inner door. The airlock test is an eight hour test with a one hour stabilization period prior to taking data.

The test duration of eight hours has resulted in relatively good data for past' tests and provides a good representation of the actual leak rate.

10CFR50, Appendix J also requires that testing be performed within three days after an airlock door has been opened during periods when containment integrity is required. This testing may be accomplished by the full Type "B" airlock test or by testing the seals for airlock doors designed to accommodate this testing. This test shall be performed at containment design pressure, unless specified differently within the Plant TS.

Palisades' escape lock is configured to allow testing between the seals, however, the door locking pins do not provide uniform closure force thus the strongbacks must be installed for all testing. The escape lock vendor has reviewed the design and determined the compression seal airlock at Palisades would not be leak-tight without use of strongbacks at. reduced pressures. The airlock was not originally designed for testing between the seals without test clamps in place.

Past TS surveillance testing has shown that testing with strongbacks in place at containment design pressure causes the seals to take a set. After strongback removal, the doors must be opened and the seals "fluffed" to obtain the sealing surface which was present prior to testing. TS Surveillance Test S0-4B recognizes the need for this post test restoration and considers this step to be part of the test. S0-4B also recognizes the need to verify proper door to seal contact after seal fluffing. This is accomplished by a visual verification of door to seal contact to verify 100 percent seating of both seals on each door and by, during periods above cold shutdown a qualitative leakage test by soap bubble application at the sealing joint.

The allowance to open an airlock door for post test restoration without further testing was believed to be acceptable, based on an August 13, 1982 conversation between Consumers Power and the NRC Proj.ect Manager for Palisades.

The conversation recognized the need for the outer door to be opened after completion of the full airlock test to remove the strongbacks installed on the inner door and resulted in agreement that this may be done without further testing.

OC0589-0022-NL02

• Nu~lear Regulatory Commission Palisades Nuclear Plant Response to IR 89~009 3

May 22, 1989 In summary, Palisades escape lock is not designed for between the seals tests without strongbacks as allowed by 10CFR50, Appendix J. Therefore, after performance of the full escapelock test the outer door must be opened to access the inner door strongbacks for removal, and both doors must be opened for post test seal restoration. Based on a past conversation with NRG, and the fact that the S0-4B results have dramatically improved since instituting post-test seal restoration in 1986, the intent of 10CFR5Q,, Appendix J is believed to have been met. Therefore, failure to meet 10CFR50, Appendix J, III.D.2.(b) (iii) as presently interpreted by the NRG, is attributed to misinterpretation of the section of Appendix J.

Corrective Actions Taken And Results Achieved To verify statements presented by the airlock vendor and Consumers Power engineering personnel's understanding of the escape lock's ability to meet a between the seals test, S0-4B was temporarily revised to perform a reduced pressure test between the seals without strongback installation. On May 10, 1989 this test was performed. During testing, the inner and outer door seals began leaking at 10 psig and 11 psig respectively when initially pressurized.

Both doors decayed in pressure approximately one second after pressurizing to 15 psig with the outer door dropping to one psig and the inner door dropping to six psig. After verifying that a~rlock design would not accommodate partial pressure between the seals testing without strongbacks, a partial S0-4B was satisfactorily performed to verify escape lock integrity in accordance

~ith TS. Since this had been a confirmatory test, no credit against TS was taken for this test in regard to the required six month frequency. The next required S0-4B is scheduled to occur before October 12, 1989.

Based on successful S0-4B test results since the institution of seal restora-tion in 1986 and the prohibitive costs of escape lock modifications, a modification to the escape lock has been determined to be imprudent.

Corrective Actions To Be Taken To Avoid Further Non-Compliance Consumers Power will provide documentation that past seal resoration is part of TS Surveillance Procedure S0-4B, as necessitated by airlock design.

Additionally, Consumers Power will provide written documentation which delineates the equivalency of the seal contact check to a reduced pressure between the seals test.

OC0589-0022-NL02

Nuclear Regulatory Commission 4 Palisades Nuclear Plant

• Response to IR 89-009 May 22, 1989 Date When Full Compliance Will .Be Achieved Full compliance will be achieved when NRC acceptance of Consumers Power's position is attained or when an exemption to 10CFRSO Appendix J III.D.2.(b)

(iii) is granted. Documentation of Consumers Power's position will be submitted by June 30, 1989.

Kenneth W Berry Director, Nuclear Licensing CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades

• OC0589-0022-NL02