ML20112H552
| ML20112H552 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 01/10/1985 |
| From: | Fiedler P GENERAL PUBLIC UTILITIES CORP. |
| To: | Zwolinski J Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8501170192 | |
| Download: ML20112H552 (2) | |
Text
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GPU Nuclear Corporation
. Nuclear
=en=388 Forked River,New Jersey 08731-0388 609 971-4000 Writer's Direct Dial Nurnber:
January 10, 1985 Mr. John A. Zwolinski, Chief Operating Reactors Branch No. 5 Division of Licensing U.S. Nuclear Regulatory Commission Washington, DC 20555
Dear Mr. Zwolinski:
Subject:
Gyster Creek Nuclear Generating Station (0CNGS)
Docket No. 50-219 Nuclear Power Plant Biofouling This transmittal is to acknowledge the receipt of your letter dated October 29, 1984 and to herein provide our response to your request for information. The numbering method is consistent with that used in your October 29, 1984 letter:
1.
Discuss, in detail, the surveillance methods that are being used to detect the presence of Asiatic clams and/or mussels in the plant Wdter supplies, fire protection systems, and systems which provide cooling for safety-related systems.
Response
There are two systems that fall within the category of plant water supplies: 1) the Circulating Water System and 2) the Service Water System.
There are no fonnal surveillance procedures in place for either system. The Fire Protection System utilizes fresh water, therefore, there are no blue mussels present; and the Asiatic clam has not been found in any of the fresh waters in the vicinity of OCNGS. The Emergency Service Water System which provides cooling water for a safety-related system is surveilled by two procedures; l) Containment Spray and Emergency Service Water Operability Test, which is conducted on a monthly basis and 2) Containment Spray and Emergency Service Water Inservice Test, which is conducted on a quarterly basis. These procedures record differential pressure across the baffle plates of the Containment Spray Heat Exchangers. An increase in pressure differential to greater than 8 psid would cause the system to be declared inoperable and would suggest biofouling and/or plugging.
In addition to these two procedures, visual inspections are made on an as needed basis mainly to determine the extent of biofouling and/or plugging and to identify the fouling material.
f 8501170192 850110 f
Oi DRADOCK05000g GPU Nuclear Corporation is a subsidiary of the General Public Util' ties Corporation
i John A. Zwolinski, Chief Page 2 U.S. Nuclear Regulatory Commission 2.
Discuss, in detail, the methods being used to control Asiatic clams and/or mussels in the plant water supplies and systems in question 1.
Discuss the consideration given to systems required to mitigate transients and/or accidents where those systems are not used during normal operation. Discuss the consideration given to protect heat transfer surfaces from clam and/or mussel infestation.
Response
For those systems that are subject to biofouling, chlorination is the primary method of biofouling control. The Circulating Water System is divided into seven (7) streams which cools the six (6) Main Condenser halves and the Turbine Building Closed Cooling Water system.
Each stream is chlorinated for 20 minutes every four hours from March to December. This chlorination scheme could possibly be limited to a l
maximum chlorination time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> per day in accordance with the i
requirements set forth in the USEPA Steam Electric Effluent Guidelines.
The requirement would become effective upon reissuance of the station's NJPDES Permit by the NJ Department of Environmental Protection (NJDEP).
i Currently GPUN has entered into negotiations with the NJDEP to obtain authorization to continue chlorination of the Main Condensers at the present schedule.
In addition, the Main Condensers are generally backwashed on a daily basis. The Service Water and Emergency Service Water systems are chlorinated simultaneously for 1 1/2 hours every four hours from March to December. However, since OCNGS received authorization from the NJDEP in September 1982 to chlorinate the Service Water (SW) and Emergency Service Water (ESW) systems, and due to operational difficulties with the chlorination system, the SW and ESW systems have been chlorinated on an intermittent basis for a total of six months.
It should also be noted that during the time period from September to present the DCNGS conducted a 20 month maintenance and refueling outage during which time the chlorination system was not operated.=
If-you have any questions or comments, please contact Mr. Douglas Moore, Environmental Licensing Engineer at (609)971-4630.
Very truly yours, t.]
i yV Fe P ter'.
f edler Vice President and Director Oyster Creek PBF/DM/ dam cc: Dr. Thonas-E. Murley, Administrator Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 NRC Resident Inspector
~ 0yster Creek Nuclear Generating Station Forked River, NJ 08731
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