ML20117G707

NPDES Noncompliance Notification:On 960715,geometric Mean of Fecal Coliform Concentration Exceeded NPDES Permit Limit. Caused by Leaking Seals on Ozone Diffusers.Temporary Adjustments Made to Ozone Gas Flow Balance

ML20117G707
Person / Time
Site:	Limerick
Issue date:	08/23/1996
From:	Boyce R PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Oneil S PENNSYLVANIA, COMMONWEALTH OF
References
NUDOCS 9609050291
Download: ML20117G707 (4)

Text

__ _ _ _ . . __ _ _ _

Robert W.Boyce

• Mant !Wnagw Umerck Generating Station A

7mer" l PECO NUCLEAR esco ce m %

Limerok Generating Station A Unit of PECO Energy PO Box 2300 Sanatoga PA 19464-0920 610 718 2000 ,

j August 23, 1996

- Mr. Steven J. O'Neil, Chief, Operations Section Department of Environmental Resources Bureau of Water Quality Management Suite 6010, Lee Park 555 North Lane Conshohocken, PA. 19428

SUBJECT:

Limerick Generating Station, Bradshaw Reservoir Non-Compliance of NPDES Permit No. PA0052221

Dear Mr. O'Neil:

DESCRIPTION OF THE NON-COMPLIANCE During the month of July 1996, Station personnel reported that the NPDES limit for fecal coliform concentration at the Bradshaw Reservoir pumps discharge into the east branch of the Perkiomen Creek was not met. The permit requires five consecutive grab samples each collected on different days, and the geometric mean of the five samples must be less than or equal to 200 colonies  ;

per 100 al. An Ozone Disinfection' System is utilized for treatment at the Bradshaw Reservoir Water Processing Facility.

On July 15, 1996, the geometric mean of the fecal coliform concentration was calculated to be 469 colonies per 100 ml, 4 thereby exceeding the NPDES permit limit. Grab sampling was conducted 18 of the 31 days in July 1996. On July 29, 1996, the fecal coliform concentration reached a geometric mean of 139 colonies per 100 m1, thereby re-establishing NPDES permit compliance.

CAUSE OF THE NON-COMPLIANCE:

The.cause of this non-compliance was degraded components in the Ozone Disinfection System. Physical inspection and testing of the ozone gas diffusers and associated piping was conducted on August 22, 1996. This revealed that the seals on many of the '

ozone diffusers were. leaking. This hampered the efficient dispersion of ozone gas in the water, which resulted in inadequate disinfection performance. ,

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" August 23, 1996 i

Page Two i

i CORRECTIVE ACTIONS TAKEN:

On August 22, 1996, adjustacnts were made to the ozone gas flow i balance to improve the performance of the system until final repairs to the diffusers can be completed. Diffusers in the final contact chamber, which were severely leaking and causing the most ozone gas to be wasted, were isolated. Flow to the

. remaining diffusers in all three contact chambers was increased

! (i.e., same total system flow).

l l CORRECTIVE ACTIONS TAKEN TO PREVENT RECURRENCE:

?

l Replacement seals for the Ozone Disinfection System are being

procured and a second outage of the system will be performed to replace the seals on all 32 diffusers. A periodic maintenance f task will be developed and implemented to detect indications of j leaks in the ozone gas system piping.

i 1

If you have any questions please do not hesitate.to contact Mr.

James L. Kantner at (610) 718-3400.

Sincerely, c t FDL/DMS e

j

cc: U. S. Nuclear Regulatory Commission Document Control Desk )

Docket Nos. 50-352/353 ,

Washington, D.C. 20555 T. T. Martin Administrator, Region I, USNRC Docket Nos. 50-352/353 N. S. Perry

- USNRC Senior Resident Inspector, LGS Docket Nos. 50-352/353 i

Program Management Section (3WM52)

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

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bcc: W. G. MacFarland -

SMB 1-1 K. S. Kemper -

SSB 2-1

] M. P. Gallagher -

SSB 3-1 2 J. L. Kantner -

SSB 2-4

, F. D. Lear -

SSB 3-1

. D. J. Cesaro -

MO S21-2

) R. M. Matty, Jr. -

MO S21-2 G. A. Hunger, Jr. -

CB 62A-1 1 Commitment Coordinator -

CB 62A-1 PA DEP BRP Inspector -

SSB 2-4

- Correspondence Release Point -

SMB 1-2

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