ML20086F322

Environ RO 77-13:on 770517,total Suspended Solids for Sewage Plant Effluent Exceeded ETS 2.2.2 Limit.Caused by Sys Upset & Greater than Normal Water Input Due to Refueling Outage. Aeration Rate Adjusted

ML20086F322
Person / Time
Site:	Peach Bottom
Issue date:	05/27/1977
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Stello V Office of Nuclear Reactor Regulation
References
RO-77-13, NUDOCS 8312210087
Download: ML20086F322 (2)

Text

O O PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET h

PHILADELPHIA. PA.19101 4'./ NI '. '\

i (2151841-4000 May 27,1977 k[ p '{ 3

\E F1LE COPY.

$,e Mr. Victor Stello, Jr, Director Division of Operation Reactors Office of Nuclear Reactor Regulations U.S. Nuclear Regulatory Commission Washington, DC 20555

SUBJECT:

ENV IRONMENTAL DEVI ATION

Dear Mr. Stello:

The following deviation was reported to Mr. Greenman, Office of Inspection and Enforcement, Region 1, United States Nuclear Regulatory Conmission on May 17, 1977

Reference:

License Number DPR-44/56 Appendix B Environmental Technical Specifications: Section 2.2.3 Report No.: 50-277/278-77-13 Report Date: May 27,1977 Deviation Date: May 17,1977 Facility: Peach Bottom Atomic Power Station Units 2 & 3 R.D. 1, Delta, PA. 17314 Identification of Deviation:

The total suspended solids for the Unit 2 and 3 sewage plant effluent exceeded the Environmental Technical Specification 2.2.2 limit.

Conditions Prior to Deviation:

On May 17,1977 the daily turbidity measurements and normal operating parameters indicated a continuing problem with the total suspended solids in the ef fluent of the Unit 2 and 3 sewage plant.

Several samples have been taken each day during this period of high

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COPY SENT REGION 8312210087 770527 PDR ADOCK 05000277 771550106 S pon

O

' Mr. Victor Stello, Jr.

O 50-277/278-77-13 May 27,' 1977' total suspended solids. The gross range was from a high of 98.2 ppm to a low of 38.8 ppm with the average being 53 9 ppm during the period from May 17 to 23,1977 The average river water total suspended solids during this sample time was 7 05 The high solids problem continues.

Designation of Apparent Cause:

A system upset brought about reduced bacterial action within the activated sludge aeration tank. The resultant sludge did not floc and settle properly. This, coupled with greater than normal water input due to the Unit 2 refueling outage, created the high total suspended solids in the system ef fluent.

Analysis of Deviation:

Because the sewage plant ef fluent is diluted by a f actor of 50,000 with circulating water flow, the suspended solids of the circulat-ing water leaving the discharge canal was not affected. Therefore, the environmental impact was minimal.

Corrective Action:

The cause of the problem was initially thought to be higher flows through the plant, which prompted cleaning of the chlorine contact tank. The degradation of the activated sludge in the aeration tank pointed to problems with the bacterial colonies. The aeration rate has been adjusted in the aeration tank to help the growth of bacteria. The bacteria should recover and form sludge which will floc and settle prope r l y. Design changes that will allow the system to be capable of responding to period of high flow are being investigated. To help establish the cause of the system upset, a consultant has been on site and will supply technical advice on the matter.

Failure Data:

Several previous occurrences.

Very truly yours, o

M. . Cooney Su erintendent Generation Division-Nuclear cc: Mr. J. P. O'Reilly NRC, Reg. Office l

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