ML20210N656

Final Deficiency Rept 85-06 Re Failure of Diesel Generators 1A & 1B to Sustain Adequate Prime During Testing.Initially Reported on 850822.Fuel Oil Sys Modified & Tested

ML20210N656
Person / Time
Site:	Braidwood
Issue date:	09/26/1986
From:	Miosi A COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
85-06, 85-6, NUDOCS 8610060606
Download: ML20210N656 (2)

Text

s b ns 43 c } Commonwealth 72 Wet Adams Stred, Edison

. -,m Chicago. llknois '

- * "' 7 Address Reply to: Post Office Box 767 Chicago, luinois 60690 - 0767 September 26, 1986 Mr. James G. Keppler Regional Administrator Region III U.S. Nuclear Regulatory Commission 799 Roonevelt Road Glen Ellyn, IL 60137

Subject:

Braidwood Station Units 1 and 2 10 CFR 50.55(e) No. 85-06 Final Report Failure of Dienol Generators to Sustain Adequate Prime NRC Docket Nos. 50-456/451

References:

(a) August 22, 1985 A.D. Mioni Letter to J.G. Koppler (b) October 21, 1985 A.D. Miosi Letter to J.G. Keppler

Dear Mr. Keppler:

The above references provided your office with information j relative to a pot.ential deficiency reportable pursuant to 10 CFR 50.55(e) regarding 1A and 1B diesel generator's failure to sustain adequate prime during testing at our Braidwood Stat. ion. This letter '

provides additional information concerning this matter and is considered a final report.

As previously reported, modifications to the fuel oil I

nynt.em were finalized in October 1984. Modifications were completed by March 1985. Preliminary testing, following a shutdown period of 18 days of both 1A and 1B diesel generators indicated the modificat.ionn were able t.o uustain fuel oil prine. However, it was det.ormined that an adequate " proof of design" would be a successful start (under 10 seconds) following a shutdown period of at least 31 days. The diesel generators were required to support other plant testing, so these modifications could not be tested to the 31-day shutdown criteria.at that time.

On August 4, 1986, following a shutdown period of 82 days, diesel generator 1B wan nLarted in under 10 seconds (5.5 seconds).

i This successful start following a shutdown period of 2.5 times greater than the normal maximum shutdown period, verifies the

! adequacy of the design change to the fuel system.

8610060606 860'726

PD9 AUCCK 05000456.

S PDR.

'0 IE 7

l Based on a review of this innue and the modifications made.

Commonwealth Edison has determined this issue not to be reportable pursuant 10 CFR 50.55(e).

Very truly yours, 5

Mf A.D. Miosi Nuclear Licensing Administrator ADM/pav Enclosure cc: NRC Resident Inspector - Braidwood Director of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555 2180K

_ - . - - _ _ . _ _ _ _ _ - . _ - - . . - _ - _ _ . _ . _ . - . _ - _ - . _ . _ . _ . _ _ _ - _ - - . ~_.a