ML19351A452

NPDES Noncompliance Notification:On 891201,water Overflowed Through Vented Manhole Upstream of Normal Final Discharge Point Into Possum Hollow Creek Approx 100 Yards Upstream from Schuylkill River.Caused by Procedural Deficiency

ML19351A452
Person / Time
Site:	Limerick
Issue date:	12/07/1989
From:	Mccormick M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Bauer R PENNSYLVANIA, COMMONWEALTH OF
References
NUDOCS 8912140420
Download: ML19351A452 (2)

Text

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1 PHILADELPHIA ELECTRIC COMPANY l 23ot MARKET STREET F.O. BOX 8699 PHILADELPHI A. PA.191o1 m i , .. .. .m>

l i

December 7, 1989 1 Mr. Robert Bauer, Jr.

Department of Environmental Resources ,

Bureau of Water Quality Management  !

1875 New Hope Street Norristown, PA 19401

Subject:

Cooling Tower Blowdown M&nhole Overflow to Possum Hollow Creek, Limerick Generating Station, NPDES Permit No. PA-0051926

Dear Mr. Eauer:

On December 1, 1989 at 4:50 p.m. oral notification was given to Mr. Lee Gemmill of the Department of Environmental Resources regarding unpermitted discharge of cooling water to Possum Hollow Creek.

f The overflow condition was a result of high water level in the Unit 2 Cooling Tower. Unit 2 reactor was shut down at 12:30 p.m. on December 1, 1989. Preparations for routine de-icing of the Cooling Tower were started by placing the tower in " winter bypass mode". This procedure involved redirecting cooling water from'the tower raceway directly to the tower basin. This change in-operating mode prevented the evaporation loss of water i normally-experienced in standard cooling tower operation. The l elimination of evaporative loss of water and subsequent increase l' in' Unit 2 cooling tower water level, combined with blowdown from the Unit 1 cooling tower, increased the blowdown rate to create the overflow condition.

At approximately 1:30 p.m. water overflowed through a vented manhole upstream of the normal final discharge point (001). The water entered the Possum Hollow Creek roughly 100 yards upstream from the Schuylkill River. An estimated 11,000 gallons were discharged to Possum Hollow before water level in the cooling tower was returned to normal. While the discharge was not from a permitted-point, a sample of the discharge showed the water to be within NPDES permit limits for outfall 001. The discharge ended at or before 2:30 p.m. with a discharge duration of approximately 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. p3 7 ' '

/- 8912140420 891 PDR- ADOCK 0 354 s PNU

[4'*' Page 2 Converting the cooling tower " winter bypass mode" involves several valve manipulations which take about 30 minutes to complete. It was during this time period that the level in the tower rose above normal operating level.

The cause of this noncompliance was a procedural deficiency.

This occasion was the first time that this procedure was used under two unit operation. The operational procedure will be revised to provide the necessary guidance to ensure that the cooling tower blowdown does not exceed the capacity of the normal discharge line. These actions are designed to prevent reoccurrence and will be completed by December 22, 1989.

Sincerely, P

t:

M. McCormick, Jr.

Plant Manager RSU:kaa  ;

cc: U. S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 Administrator Region I Office of Inspections and Enforcement U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Station Resident NRC Inspector Tom Kenny, M.C. #NRC Program Management Section (3WM52)

Permits Enforcement Branch Water Management Division i Environmental Protection Agency Water Permits Section Region III 841 Chestnut Building Philadelphia, PA 19107 4