ML20091R228

Responds to NRC 821220 Request for Addl Info Re Response to IE Bulletin 81-03 on Flow Blockage of Cooling Water by Mussel & Asiatic Clam.Emergency Svc Water Pump & Piping Inspected.No Significant Blockage Detected

ML20091R228
Person / Time
Site:	Oyster Creek
Issue date:	06/08/1984
From:	Fiedler P GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
References
IEB-81-03, IEB-81-3, NUDOCS 8406150040
Download: ML20091R228 (3)

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GPU Nuclear Corporation NggIgf Post Office Box 388 Route 9 South Forked River.New Jersey 08731-0388 609 971-4000 Writer's Direct Dial Number:

June 8, 1984 Director Division of Engineering and Quality Assurance Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Oyster Creek Nuclear Generating Station IE Bulletin No. 81-03 Request for Additional Information On December 23, 1982, GPU Nuclear (GPUN) received your letter dated December 20, 1982, requesting additional information concerning our initial response to IE Bulletin No. 81-03 Plow Blockage of Cooling Water to Safety Components by Corbicula sp. (Asiatic Clam) and Mytilus sp. (Mussel) dated May 29, 1981.

Subsequently, GPUN initiated appropriate action to adequately respond to your request. On August 25, 1983, GPUN submitted a response to item 4a and advised that items 2 and 5e would be addressed in future correspcadence. The following are the " Actions to be taken by Licensees" as described in the bulletin and GPUN's responses to the aforementioned items. @e numbering method is consistent with that used in the bulletin and your December 20, 1982 letter:

2. If it is unknown whether either of these species is present in the local environment or is confirmed that either is present, determine whether fire protection or safety-related systems that directly circulate water from the station s)urce or receiving water body are fouled by clams or mussels or debris consisting of their shells. An acceptable method of confirming the absense of organisms or shell debris consists of opening and visually examining a representative sample of components in potentially affected safety systems and a sample of locations in potentially affected fire protection systems.

The sample shall have included a distribution cf components with supply and return piping of various diameters which exists in the potentially affected systems. m is inspection shall have been conducted since the last clam or mussel spawning season or within the nine month period preceding the date of this bulletin. If the 8406150040 840608 PDR ADOCK 05000219 PDR 0

$s ' g GPU Nuclear Corporation is a subsidiary of the General Public Utikties Corporation I D

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Director:

'Divizion of Engineering and Quality Assurancs

U.S. Nuclear Regulatory Commission Page-2 absence of organisms or shell debris has been confirmed by such an

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inspection or another method which.the-licensee shall describe in the response'(subject to NRC evaluation and acceptance), no further Laction is necessary except for items 4 and 5 of actions applicable to holders of an operating license.

Remym

'As requested, additional inspections were conducted of the'following couponents: Emergency Service Water.(ESW) Pump internals, ESW piping downstream of the.ESW pumps, and ESW piping upstream of the Containment y ' Spray Heat Exchangers (CSHE). In all areas examined there was no significant blockage detected to cause flow reduction. 'me maximum .

Diofouling layer observed was approximately 2 to 3 centimeters thick.

. Additionally, there were no blue mussels (Mytilus edulis) observed in any of the areas: inspected. ;In an effort to better monitor the condition of the.CSHE, pressure-gauges have been installed on the Containment spray Heat Exchanger pass partition plates for the tubeside flow passes. % e gauges provide differential pressure between two passes and also overall

, pressure drop in the CSHE tubeside. Also, flow measurements are taken which will provide an indication of increases'in biofouling.

I 5.e'.~ Provide results and conclusions of chlorination feasibility. study as j they.become available.

, Response As stated in our August 25, 1983 letter,'an evaluation of-the Containment

. Spray Heat Exchanger biofouling was conducted. 21s resulted in a recommendation for consideration for providing an. oxidant injection point immediately before the containment Spray Heat Exchanger.; Upon further E ' consideration of that recomunendation and evaluation of the existing chlorination system it was determined that the existing system, with the

' installation of a new service water booster pump to improve the flow of ,

chlorinated water, is expected to meet the requirement for controlling x biofouling in the Containment Spray Heat Exchanger.

, 30 x

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r Director Divicion of Engineering and Quality Assuranc2 U.S. Nuclear Regulatory Commission Page 3 21s concludes our response to your December 20, 1982 letter, and if you have any further questions or require additional information please do not hesitate to contact Mr. Douglas Moore of our Licensing and Regulatory Affairs Department at (609)971-4630.

Very truly yours, ad ^ S Yan 3 te Fiedler Vice President and Director Oyster Creek PBF:DM: dam cc: Dr. S omas E. Murley, Administrator Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731