ML20107F963

NPDES Noncompliance Notification:On 840828,reactor & Turbine Manually Tripped Due to Max Influx of Fish Blanketing Screen.Caused by Severe Anoxic Conditions.Biofouling Task Force Working to Improve Screen Performance

ML20107F963
Person / Time
Site:	Calvert Cliffs
Issue date:	09/28/1984
From:	Bauereis E BALTIMORE GAS & ELECTRIC CO.
To:
References
NUDOCS 8411070185
Download: ML20107F963 (1)

Text

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i September 28, 1984 TO: Mr. John Veil Office of Environmental Programa FROM: Dr. E. I. Bauereis r

SUBJECT:

Impingement Episode at Calvert Cliffs fiuclear Power Plant According to the NPDES permit (MD0002399) for Calvert Cliffs Nuclear Power Plant under I. Special Conditions, H. Intake Monitoring,

.any impingement episode substantial enough to c%use modification to nlant operations is'a reportable event.

On August 28, 1984 Calvert Cliffs Nuclear Power Plant Unit 1 reactor and turbine were manually tripped. At 9:50 p.m. on August 28, 1934

1. 11 circulating water pump was stopped when 11A and 11B traveling screens

- developed a 40 ineh differential vater level due to a massive influx of fish blanketing the screens. Subsequently, at 9:56 p.m. 12A and 12B screens <

developed a differential vater level of 50 inches resulting in stopping #12 circulating water pump and the resetor was manually tripped. -

Thri Outside Operators Log for August 26, 198h shows severe. anoxic i conditions in the Chesapeake Bay adjacent to the Calvert Cliffs Nuclear Power Plant. In the early afternoon (1 p.m.) when oxygen concentrations should be greater than 5.5 mg/1, the dissolved oxygen measured 1.7 mg/1. The severe anoxic conditions (less than 3 ug/1) at least 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> before the impingement  :

event probably resulted in severely stressed or morbid fish. Under these unusual circumsfances there is little that can be done to prevent the fish kill but the Biofouling Task Force is working to improve the performance of the traveling screens. I Copies of the report by the biologist performing the imping ment sampling and the Outside Operators Log for August 28, 1934 are attached.  ;

If you have any questions regarding .this letter report, please ,

call me at 301/234-6533.

$/) N h & , k /$

Senior Biologist Environmental Programs EIB/rev e4110 185 840928 PDR A K 05000317 i s PDR Attachment cc: Messrs. A. E. Lundvall, Jr G. R. Fuhrman T.Foley,N.R.C.! R. C. L. Olson C. II. Cruse L. B. Russell P. T. Crinigan J. A. Tiernan off

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