ML20101H532

NPDES Noncompliance Notification:On 920504,crack Discovered on Above Ground Cleanout for Sewage Line Leading from Plant Training Ctr to Plant Sewage Sys Holding Tanks.Caused by Expansion of Sewage Spill Line.Clamps Installed

ML20101H532
Person / Time
Site:	Limerick
Issue date:	06/26/1992
From:	Doering J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Bauer R PENNSYLVANIA, COMMONWEALTH OF
References
NUDOCS 9206300025
Download: ML20101H532 (3)

Text

1 PHILADELPHIA ELECTRIC COMPANY LIMERICK GENER ATING ST ATION P. O. DOX A S AN ATOG A. PENNSYLV ANI A 19464 (215) 327 1200 art. 2000 June 26, 1992

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6.............. .

Mr. Robert Bauer, Jr.

Department of Environmental Resources Bureau of Water Quality Management Suite 6010, Lee Park 555 North Lane Conshohocken, PA 19428

Subject:

Limerick Generating Station; Noncompliance with NPDES Permit ho. PA-0051926; Sewage Line Cleanout Leak Seeping into Possum Hollow Creek

Dear Mr. Bauer:

DESCRIPTION OF THE EVENT On May 4, 1992, at 1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br /> during a routine walkdown of the sanitary sewer system by the facilities engineer, a crack was discovered on an above ground cleanout for the sewage line leading from the Limerick Training Center to the Limerick Generating Station (LGS) sewage system holding tanks. A mist of sewage was spraying from the crack onto the ground in a circular pattern of approximately 5 feet in diameter, within 5 feet of the Pos um Hollow

, Creek. Site Chemistry personnel were then notified of the condition j and performed sampling upstream and downstream of the leaking l cleanout tc determine whether sewage had entered the creek.- Fecal coliform analysis results indicated that sewage was seeping through the soil and surface rock and entering Possum Hollow Creek.

Analysis of the samples indicated that the fecal coliform concentration decreased to below the. background level in the creek at approximately 250 feet downstream of the leaking cleanout prior to reaching the Schuylkill River. This event was a non-compliance of the LGS _ NPDES permit which exceeded effluent limitations g specified in the permit and did not endanger health or the ne environment.

ano NOA 40 The leak was stopped on May 4, 1992, and additional samples were j 08 taken'on May 7, 1992, after it had rained. These results indicated 1 SO that fecal coliform concentration had decreased to less than the gg background at 10 feet downstream of the cleanout.

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@O _D,URATION OF THE NONCOMPLIANCE n

om Since the crack in the above ground cleanout was discovered during a hm sanitary sewer system walkdown, and no prior system walkdowns had /

been performed, the date that the discharge started could not be determined. Therefore, the total seepage ' nto t he creek and the - p

Page 2 duration of the noncompliance could not be determined.: :The sewage line leading.from the Limerick Training Center to LGS was installed in November, 1991. It is believed that the crack occurred during the past winter freezing cycle, possibly in February, 1992.

However, due to the small ground area which was affected by the spray, the low flow from the crack in the cleanout, and the short stretch of the creek affected, the overall effect on the environment was minimal.

CAUSE OF THE NONCOMPLIANCE The cause of the noncompliance was a cracked above ground cleanout resulting from_a failure to consider the environment in whien the-cleanout pipe was installed during design of the system. A portion of the cleanout line at the low point of the sewage piping trom the Training Center was-installed above ground levei without_the use of heat trace. This resulted in expansion of the sewage' filled line during the winter months, resulting in'a cracked pipe,' allowing: .

sewage under pressure to spray out.

CORRECTIVE ACTION The leak was stopped by 1400 hours0.0162 days <br />0.389 hours <br />0.00231 weeks <br />5.327e-4 months <br /> on May 4, 1992, by the installation of packing gland material-and clamps.

PREVENTIOW OF FUTURE OCCURRENCES The following actions were implemented to prevent the recurrencelof a similar event.

1. The above ground cleanouts at the location of'the leak ~and at an additional location about 100 feet south of the led, were re-located below the fiost-line.

2. A thorough walkdown of the sewage system wasiperformed_to verify that there were no similar problems in other locations. No-additional problems were. identified.

Sincerely, b, - rf &

KOS:cah cc: U.S. Nuclear Regulatory Commission Document Control Desk Docket Nos.: 50-352/50-353-Washington, D.C. 20555 I T. T. Martin Administrator, Region-I, USNRC Docket Nos. 50-352/50-353 H i

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r Page 3 T. J. Kenny USNRC Senior Resident Inspector, LGS Docket-Nos. 50-352/50-353 Program Management Section (3WM52)

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

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