ML20153H044

Confirms Agreement Re Insp Schedule for Recirculating Sys Piping/Supports Per IE Bulletin 79-14 & 850723 Insp Rept 50-219/85-22.Inaccessible Portions of SEP Piping Sys Will Be Reinspected During Oct/Nov 1985 Outage

ML20153H044
Person / Time
Site:	Oyster Creek
Issue date:	10/28/1985
From:	Wilson R GENERAL PUBLIC UTILITIES CORP.
To:	Ebneter S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
IEB-79-14, RFW-0665, RFW-665, NUDOCS 8602280585
Download: ML20153H044 (2)

Text

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100 Interpace Parkway Parsippany, New Jersey 07054 201 263-6500 TELEX 136-482 Writer's Direct Dial Number:

October 23, 1985 RFM - 0665 Mr. Stewart D. Ebneter, Director Division of Reactor Safety U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Subject:

Oyster Creek Nuclear Generating Station Docket No. 50-219 IE Bulletin (IE8) No. 79-14 Reinspection Program The purpose of this letter is to document our recent agreement with Mr. J.

P. Durr of your office concerning the inspection schedule for Recirculation System piping / supports (Understanding (2)(a) of Inspection Report 50-219/85-22). Additional information is also provided for Understandings No.

I and 3 of Inspection Report 50-219/85-22 which was transmitted to us by your letter dated July 23, 1985.

As it was explained in our recent phone conversation with Mr. Durr, Oyster Creek Recirculation System will be decontaminated to conduct Induction Heating Stress Improvement (IHSI) of the piping welds during Cycle 11 refueling outage scheuled to commence in April, 1986. The reduction in radiation exposure by deferring the Recirculation System piping / supports inspection until after the IHSI, is expected to be significant (approximately 18.5 man-rems). This will also enable us to inspect the pipe supports in their "re-assembled" configu-ration following the IHSI during which some supports may be disassembled. On August 29, 1985 Mr. Durr, in his phone conversation with GPUN staff (M.

Laggart), stated that the deferment of the inspection for the remaining Recirculation System lines / supports is acceptable provided that no significant discrepancies were found on the loop hiready inspected. During a plant shutdown in June 1985 one complete loop of the Recirculating System was inspected and no significant discrepancies were found on 21 supports inspected, i The scope of our planned reinspection effort does not include the removal of thermal insulation which obstructs the inspection of support details or prohibits the determination of the location of pipe supports within inspection tolerances. The justification for this exception to the requirements of IEB No. 79-14, Supplement 2, Page 2 of 2 is based on a sample population of 218 uninsulated and insulated but inspectable supports outside the drywell. l Approximately 3 to 5% of these supports were found to have discrepancies which could affect the function of the support. For the supports inspected inside the drywell, for which complete inspection without removal of insulation was possible (5 total), no significant discrepancies were discovered. Based on this sampling we feel removal of insulation at this time is not warranted.

However, as a confirmatory measure, several piping systems inside the drywell 0602200505 051028 DR ADOCK 050 g 9 urU Nuclear is a part of the General Pubhc Uhhties System IE u

. . will have their insulation removed during the April 1986 refueling outage for reasons other than IEB No. 79-14 inspection. At that time the support details which were hidden by the insulation will be inspected to confirm the findings of our original sample. If significant discrepancies exceed the findings of the original sample, then further insulation removal and reinspection would be justified.

GPUN letter dated July 1, 1985 to Mr. J. A. Zwolinski, Operating Reactors Branch No. 5, NRC, transmitted Material Non-conformance Reports (MNCRs),

marked -up support and isometric drawings for Control Rod Drive Return, Liquid Poison, Main Steam, Core Spray, Feedwater and Isolation Condenser System piping which are the six piping systems reviewed under the Systematic Evaluation Program (SEP). The July 1, 1985 letter also reported that our '

independent assessment of the MNCRs for the Control Rod Drive Return and Liquid Poison Systems indicates that the deviations shown in the MNCRs have no effect or only a negligible effect on the results of piping stress analyses that were submitted previously and therefore, it'is concluded that the deviations are acceptable. Our recent assessment of the MNCRs for the remaining systems (i.e., Main Steam, Core Spray, Feedwater and Isolation Condenser Systems) also indicate that the deviations shown in the MNCRs have no effect or only a negligible effect on the results of piping stress analyses that were submitted previously and therefore, it is concluded that the deviations are acceptable. It must be noted, however, that only the accessible portions of the SEP piping systems inside drywell (i.e., Main Steam, Core Spray and Feedwater Systems) were re-inspected during the June 1985 forced-outage. The remaining portions will be re-inspected during the current October / November 1985 outage. The results of the review of the remaining portions will be transmitted to you as they become available.

Very truly yours,

. on Vice President Technical Functions RFW:gpa 2371f/001 cc: Mr. John A. Zwolinski, Chief Operating Reactors Branch No. 5 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D. C. 20555 Administrator U.S. Nuclear Regulatory Commission 631 Park Avenue -

King of Prussia, PA 19406 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, New Jersey 08731 J. Donohew U. S Nuclear Regulatory Commission 7920 Norfolk Avenue Bethesda, Maryland 20014

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