ML20098G557

Submits Supplemental Info in Response to IE Bulletin 84-01, Cracks in BWR Mark I Containment Vent Headers. Program Initiated to Address Concerns of GE SIL 402 & Implementation Schedule

ML20098G557
Person / Time
Site:	Oyster Creek
Issue date:	09/14/1984
From:	Fiedler P GENERAL PUBLIC UTILITIES CORP.
To:	Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
IEB-84-01, IEB-84-1, TAC-54150, NUDOCS 8410050133
Download: ML20098G557 (2)

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

September 14, 1984 Dr. Thomas E. Murley, Administrator Region I U.S. Nuclear Regulatory Comission 631 Park Avenue King of Prussia, PA 19406

Subject:

Oyster Creek Nuclear Generating Station Docket No. 50-219 IE Bulletin 84-01 Supplemental Information Our letter to you dated February 10, 1984 provided a response to the subject Bulletin concerning" Cracks in Boiling Water Reactor Mark I Containment Vent Headers".

In that letter we indicated, based upon inspection results, that cracks in potentially affected piping were not evident at Oyster Creek.

The purpose of this letter is to inform you of the program we have initiated to address the concerns of General Electric Co. (GE) SIL No. 402 and our implementation schedule. Responses to the five (5) recommendations made in I

the GE SIL are as follows:

i 1.

Evaluate Inerting System Design An evaluation of the nitrogen inerting system design has been initiated.

The potential for introducing cold nitrogen gas or liquid into the drywell and wetwell will be investigated. Completion of this evaluation is expected during cycle 10 operation and any modifications identified will be performed during the Cycle 11 refueling outage. We have previously determined that the nitrogen injection port (vacuum breaker line) for the wetwell is offset from the wetwell centerline.

2.

Evaluate Inerting System Operation Difficulty has been experienced with nitrogen inerting system operation in the past. The operational difficulties resulted in the inability to achieve adequate nitrogen gas flow rate for timely inerting immediately prior to power operation on several occasions. During the summer of 1982 system problems were diagnosed and corrective actions implemented which have greatly improved its operation. In addition, additional terms and conditions were included in the purchase order for the nitrogen supply system which is vendor-owned and maintained.

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GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation

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Dr. Thomas E. Murley, Administrator Page 2 R:gisn I x

Tnese include a quarterly inspection and service coordinated and verified by GPU Nuclear personnel. A report of as-found and as-left equipment condition, parts changed and modifications installed during servicing is required. An annual statement of the working condition of the nitrogen supply equipment is also required.

Appropriate temperature limits for nitrogen injection into containment are incorporated in plant procedures. Nitrogen inerting system monitoring instrumentation (temperature, pressure and flow rate) are calibrated and maintained by plant personnel in accordance with plant procedures. These indications are provided in the control room.

3.

Test for Drywell/Wetwell Bypass Leakage A bypass leakage test will be performed prior to startup from the current outage in conjunction with the Integrated Leak Rate Test.

4.

Inspect Nitrogen Injection Line A total of fifty-two (52) out of sixty (60) welds have been inspected from the last isolation valve up to the drywell and wetwell penetrations.

Two of the welds were radiographed while the remainder were inspected ultrasonically. The eight (8) remaining welds were eitner inaccessible or could not be adequately tested t31ng these methoits (these wbre 'one ' inch and smaller socket weld pipe fittings). The inspection results were found acceptable.

5.

Inspect Containment Visual inspection of applicable components in the wetwell has been performed as described in our February 10, 1984 letter.

If you should have any questions regarding the above, plea:e contact the undersigned or Paul F. Czaya at (609)971-4893.

ry truly

urs, 7g A t. J f*.

ster B. Fiedler

'ce President an Director ster Creek PBF/ dam cc: U.S. Nuclear Regulatory Comission Document Control Desk Washington, DC 20555 Mr. Walter A. Paulson, Acting Chief Operating Reactors Branch No. 5 Division of Licensing U.S. Nuclear Regulatory Commission Washington, DC 20555 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked Riverm NJ 08731 u