ML20042D489
| ML20042D489 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 12/28/1989 |
| From: | Fitzpatrick E GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-89-10, IEB-85-003, IEB-85-3, NUDOCS 9001090196 | |
| Download: ML20042D489 (4) | |
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GPU Nuclear Corporation -
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Q gf Post Office Box 388 ' ~
Route 9 South Forked River,New Jersey 087310388 609 971 4000 -
Writer's Direct Dial Number:
-December 28', 1989 U.S. Nuclear Regulatory Commission Document Control Desk Washington,"DC-20555 i
Dear Sir:
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Subjects Oyster Creek Nuclear Generating Station Docket No. 50-219' Response to Generic Letter 89-10 On June 28, 1989, the U.S. Nuclear Regulatory Commission issued Generic Letter 89-10 " Safety Related Motor-Operated Valve Testing and Surveillance",
containing a six month reporting requirement., The six month report wasLto.
contain each licensee's concurrence or exception to the recommendations'and -
schedules specified in the Generic Letter. Attachment I to this' submittal I
fulfills the six month reporting requirement.
If any f.srther information is required, please contact Mr. John Rogers at.
609-971-4893.
ry truly yours,:
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.E.
Fitzp ick ice Presialent'& Director Oyster Creek EEF/JR/jc (13) cc Mr. William T. Russell, Administrator Region I U.S. Nuclear' Regulatory Commission 475 Allendale Road-g!
King of Prussia, PA 19406 l
Mr. Alexander W. Dromerick U.S. Nuclear Regulatory. Commission Washington, DC 20555 NRC Resident' Inspector Oyater Creek Nuclear Generating Station j
y 9001090196.891228
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{DR ADOCK0500g9 GPU Nuclear Corporation is a subsidiary of the General Pubhc Utilities Co,rdoration
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Response to Generic Letter 89-10 A. Recommendations Generic Letter 89-10 recommends that the licensee develop a program to coordinate the design basis review, baseline testing and periodic retesting-of motor operated valves (MOVs) within safety-related systems. The letter q
also recommends that design basis flow and differential pressure testing be i
performed on as many Movs as practicable.
Full compliance with the i
recommendations of the Generic Letter invclves establishing a program which encompasses several major sections.
In GPUN's initial response to IEB 85-03 GPUN stated that "in 1984 Oyster -
Creek implemented a program which encompasses most of the requirements of action items a,b,c, and-d of IEB 85-03.
The attributes of CPUN's program include:
1.
Investigation of the actual design basis of the torque switch settings; i
2.
Determination of the appropriate torque switch setpoints; 3.
Resetting the torque switches on all applicable valves as required; I
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Issuance of a Maintenance Procedure to control torque switch j
settings on safety-related and containment Isolation Motor Operated i
Valves.*
l The scope of the program described in the IEB 85-03 response included most of the safety related systems; the major exception.being the system boundary function of the recirculation system. The scope of the program for these systems-included those valves which are required to be tested;for operational readiness in accordance with 10CFR50.55a(g) and those valves.
which perform a containment isolation and/or; safety-related function.
GPUN will use the existing Oyster Creek program as the basis for improvements to address the recommendations of Generic Letter 89-10 except as noted below I
Scope:
The scope of the existing program will be expanded to include all MOV's in safety-related piping systema not blocked from advertent operation using our currently accepted practices for prevention of inadvertent operation.
pesian Basis Reviews Only those events within the approved Oyster Creek design basis, as l"
documented in the updated Final Safety Analysis Report, will be considered.
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Page 2 of 3 Determinino Correct Switch Settinos GPUN currently uses analytical methods which determine thrust requirements and design basis conditions.
Several of the factors used 1
in the calculations are currently the subject of NRC and industry group j
evaluations.
These factors include, but are not limited tot valve a
factor, hydraulic effects caused-by piping configurations,, stem j
lubrication allowances and rate of loading of spring packs. Any of these items could potentially require a revision to the methodology H
employed by'GPUN.
Revisions to the existing analytical methodology utilized to determine correct switch settings will be made as appropriate-when these evaluations are finalized.
j Verification of Switch Settinos The Generic Letter recommends methods to initially verify by testing and to periodically reverify that the switches of each Mov are properly set i
thereby ensuring that the MOV can meet its design basis function, the existing Oyster Creek MOV-testing program employs dynamic testing apparatus at static plant conditions to verify proper switch settings.
Revisions to the existing test methodology will be made as appropriate when the industry developed databases indicate that different methodologies will yield more accurate resulta.
The Generic Letter also recommends that_. full flow differential pressure testing be performed for all MOVs in-the program. Where full flow in-situ testing cannot be performed due to plant. constraints, the Generic Letter recommends full flow differential pressure testing be performed on prototype MOVs with documentation sufficient to validate repeatability with the in-situ Movs. As interim measures,,the Generic Letter allows-analytical methods employing conservative extrapolation from lower than full flow differential pressure testing;to be considered until prototype testing is completed. GPUN does not agree that-implementation of these recommendations is prudent at the present timo for the following reasons:
a.
In-situ testing of each MOV under full flow differential j
pressure conditions is Lmpractical from a> plant safety' viewpoint.
Configuring plant systems to worst case design basis I
conditions for proving operability and collecting data by unvalidated techniques is unprecedented. GPUN does not routinely subject the plant to design basis conditions without utilizing techniques accepted by both the nuclear. industry and
-Nuclear Standards Committees. Additionally, the program required to implement this testing is in direct. conflict with existing programs to reduce theinumber of unnecessary challenges-to operators and Engineered Safeguard Systemn.
b.
The alternative methods of full flow differential _ pressure 4
testing allowed by the Generic Letter will require the formulation of testing criteria, systems and databases _not currently developed within the industry.
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Page 3 of 3 c.
The methodology for establishing valve _ similarity in order to provide adequate justification for not differential = pressure testing is not currently developed within the industry..
Defining similarity is key for being'able to provide adequate justification based on test results from other valves,-whether in-plant or prototype.
d.
The orderly formulation of programs or the research required to allow extrapolation of the-full-flow differential pressure-testing values with low pressure test criteria may.take longer than envisioned by the NRC and thus may notLsupport a 5. year time frame for completion of the program.
Existing design margins which conservatively bound valve actuator' sizing factors will be considered acceptable justification for not differential' pressure testing unless-proven otherwise.-
o For the reasons stated above, GPUN proposes to perform-in-situ' full flow differential pressure tests only on those MOVs where this is possible without violating Technical Specifications or placing the' plant systeme11n an unsafe configuration. Other MOVs which cannot meet;such testing-limitations will be in-situ tested under the interim measures described in the Generic Letter. -This program will be implemented to allow sufficient' time for the industry to formulate accurate, repeatable and uniformly l
acceptable testing methods. This will result in.a significantly better program which is more representative of actual system configuration during=
accident conditions. The intent of the Oyster Creek program will be to
'i integrate sound engineering determinations with test results to ensure MOV-operability.
j B. Schedule The Generic Letter recommends completion of. scheduling and program' information within one year of~ June 28, 1989' and that all. baseline. testing be complete within five years or three refueling outages from June 28, 1989. GPUN will implement the schedule for completing.the recommendations within three. refueling outages for Oyster Creek with the exceptions as discussed above.
' l However, industry findings and developments that-alter the' program approach will necessarily cause affected program elements to extend beyond the I
specified time period.. Therefore, if the critical valve variables necessary -
to define valve similarity.and the extrapolation methods for testing.at
. I non-design basis conditions are delayed in development, certain program elements will extend beyond the specified time period.
I JR-LTRS (13-16)-
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