ML20086F412

Revised RO Re Plant Iodine & Particulate Release Rate Exceeding 4% of Tech Spec 3.8.C.2 Averaged Over Fourth Quarter 1976.Caused by Leaks in Reactor Water Cleanup Sys. Leaks Repaired & Equipment Modified to Reduce Leakage

ML20086F412
Person / Time
Site:	Peach Bottom
Issue date:	12/09/1976
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19289B554	List: ML20086F409 ML20086F412 ML20086F418 ML20086F422 ML20086F470 ML20086F473 ML20086F482
References
NUDOCS 8312270033
Download: ML20086F412 (3)

Text

{{#Wiki_filter:. PHILADELPHIA ELECTRIC COMPANY ", 2 i

                                                                                                    r 2301 M ARKET STREET                                        ]

I PHILADELPHIA. PA.19101 l l tats:8414ooo Deceeber 9,1976 Re Docket ' Noi# 50-277 50-278 Mr. J. P. O'Rei lly Director, Region 1 . Office of Inspection and Enforcement U.S. Nuclear Regulatory Consatssion , 631 Park Avenue , King of Prussia, Pa. 19406 [

SUBJECT:

Unique Report for Plant Iodine and Particulate Release Rate Exceeded F our Percent of Technical Specification 3.8.C.2 Averaged Over the Fourth Calendar Quarter of 1976

Dear Mr. O'Reilly:

This letter is being transmitted in ace.:ordance with the unique reporting requirements specified in Technical Specification 3 8.C.3.b, which states that the Director of Region I should be informed when the 3 release rate exceeds four percent of Technical Specification 3.8.C.2 when averaged over -a calender quarter. Apparent Cause e The sources of the releases of I-131 and particulates during the fourth quarter of 1976 were leaks in the reactor water clean-up , systems (RWCU) . The major isotope was 1-131 with particulates having j half lives greater than eight days conprising only ten percent of the 4 total releases. During the first five weeks of the quarter approximately eight-five percent of activity released was from the Unit 2 reactor and turbine building ventilation systems..with the remainder from the  ; Unit 3 system.  :. Analysis of Occurrence

                                                                   ,                                         c, Most of the primary coolant leakage which contributed to the-                      ,

I releases was from the Unit 2 RWCU regenerative heat exchange head flanges;,,, Two othar incidents have occurred which were significant contributors to  : the release rates. _ The first was a leak on a_ Unit'2 instrument nitrogen 1 l t compressor on Noven6er 10. The second was a normal nuclear system depres-surization associated with a shutdown'of Unit 2 reactor on Noven6er 14. " kk S 0 _

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Mr. J. P. O' Rail y Pcgo 2 Decenber 9. I 976 9 k Corrective Action As notad in the unique Report of Hovember 17, 1976 and the response to Inspection Mos. 50-277/76-35 and 50-278/76-25, in conjunction with repufrs, equipment nodificatiens are being made which will reduce leakage. When a leak was located, repairs were initiated insaediately. Becauso of the recurring nature of the leaks, the Stand-Dy Gas Treatment (SBGT) aystem has been placed in service to process the effluents from the reactor building aqalpment cells during reactor shutdowns. This hes significantly reduced the release rates of todino and partic-u l ate s . In addition to utilization of the SBGT system to reduce the release rates, reactor pressure rate of decay has been reduced to allow increased ef ficiency of the reactor water cleanup system. The RWCd regenerative heat exchanger locks are expected to be stopped by the installation of wolded suels on the flanges. This permanent modification is expected tn be in service on both units prior to July of 1977 The feasibility of adding more charcoal filters to the equipment cell ventilation system is also under study. Very truly yours,

                                                         /

H. . Cooney Su rintendent Generation Division-Nuclear cc: Mr. J. G. Davis, NRC Mr. W. G. Mcdonald, MtC Revisod December 20, 1976 i f

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