ML19343B400

Forwards LER 80-031/01T-0

ML19343B400
Person / Time
Site:	Peach Bottom
Issue date:	12/12/1980
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19343B401	List: ML19343B400 ML19343B402
References
NUDOCS 8012230352
Download: ML19343B400 (3)

Text

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. n E fl PHILADELPHIA ELECTRIC COMPANY

$ .,,, 2301 MARKET STREET i ec n W c:

[,, l P.O. BOX 8699 n '.

rF.. r PHILADELPHI A. PA.19101 k' (21st 84 t-4000 8

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D December 12, 1980 f Mr. 3oyce H. Grier, Director j Office of Inspection and Enforcement Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

SUBJECT:

Licensee dvent Report Narrative Description The following occurrence was reported to Mr. Cowgill,  ;

Region I, Office of Inspection and Enforcement on November 26, '

1980.

Reference:

Docket Number 50-277 Report No.: LER 2-80-31/1T Report Date: December 12, 1980 occurrence Date: November 26, 1980 '

Facility: Peach Bottom Atonic Pouer Station.

. RD F1, Delta, PA 17314 Technical Specification

Reference:

Technical' Specification 3.2.'D.1(a) states in part that, "Except as specified in (b) below,'both steam air ejector off gas system radiation monitors shall be operable during reactor power operation..."

~

Technical Specification 3.2.D.1(c) states in_part that, "Upon the loss of both off gas system radiation. monitors, either temporary monitors shall be used...or initiate an' orderly shutdown." ,

Technical Specification 3.8.C.8 states in part'that-

"...the off gas radiation monitors shall be operable-or~ operating whenever steam pressure is available to the air ejectors."

$ sonaan

?! r . Moyce H. Grier Page ?

Decenber 12, 1980 LER 2-30-31/lT Description of the Event:

At approxinately 6:30 AM on Novesiher 23, 1930, foIlowing a II n i t 2 load reduction, the off nas stack radiation nonitor low flow alarn annunicated in the control roon. Shift personnel pronptly investigated the problem, found water in the off gas radiation monitor sampling systen, and attempted to reestablish full sanple flow. The low sample flow problem was completely resolved by approximately 9 AM November 24, 1980. It was believed by shift supervision that the off nas radiation monitoring systen was operable during the event even though the sample flow was reduced. Subsequent investigation conpleted on

!!ovember 26, 1980, indicates that the off gas radiation monitoring systen was inoperable for periods of time during the event. f Probable Consequences of the Occurrence:

Although relatively minor power level changes were nade during the period of inoperability, off gas values were similar before and after the event. Additionally, weekly off gas grah samples which were analyzed for isotopic conposition indicated no unanticipated change from previous weekly sanples. Other process radiation instrumentation which nonitors for fuel failures (main stean line nonitors) showed no unexpected changes during the event.

The off gas radiation monitors at Peach liotton are used for operator information only. Additionally, off gas fron the condenser is processed through a recombiner into a five-day acidup pipe prior to release. Therefore, there would have been ample opportunity to prevent the release of any high activity gas had such a situa. tion occurred coincident with off gas monitor inoperability.

Cause of the Event:

Due to a power reduction initiated at approximately 10 P!! on November 22, 1980, systen dynamics in off nas processing and sampling systeu t rans f e rred water from the normal collection and drain systen into the sample systen. This resulted in a reduction of off gas sanple flow to the radiation detectors. Our investigation has deternined that a recent nodification to the collection and drain systen conbined with minor pressure variations resulting from the power reduction caused water carryover into the sampling systen. This water reduced sample @

flow and thus rendered the systen inoperable. y N

IQ E

i 11 r . Royce 11 . Grier P .' n e 3

, December 12, 1980 LE tt 2-80-31/IT Corrective Action: ,

The inmediate corrective action was to purge the sampling system of water and reestablish normal sample flow.

Full sanple flow was reestablished the morning of Novenber 24, 1980 as discussed above.

A temporary off gas radiation monitoring system was installed on November 24, to permit special testing.of the permanent monitoring system. The results of the testing performed on November 25 and 26 indicate that the off gas monitoring system had been inoperable for periods of time during the event.

The drain system for the off gas monitor s a m p l i n t; systen will be modified. Until the modification is completed, special operating measures are being taken to avoid a similar occurrence.

Additionally, the tenporary system has been left in service to act as a backup.

Very truly yours, f GfmLCc ,

'i

• !! . J.

j Cooney Supjerintendent Generation Division / Nuclear Attachment cc: Director, NRC - Office of Inspection & Enforcement if r . Nornan II . It a ll e r , NRC - Office of }fanagement &

Program Analysis

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