ML20066J523
| ML20066J523 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 01/26/1991 |
| From: | William Cahill, Walker R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-91046, NUDOCS 9102040225 | |
| Download: ML20066J523 (4) | |
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EE Log # TXX-91046 2
File # 10010
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916 TUELECTRIC January 26, 1991
$N"b' 'l$$U V. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.
20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NO. 50-445 WAIVER OF COMPLIANCE FOR INSERVICE TESTING REF:
Thomas E. Murley, NRC Memorandum, Temporary Waivers of Compliance, dated February 22, 1990.
Gentlemen:
In accordance with the guidance provided by the referenced memorandum, TV Electric hereby requests an NRR Waiver of Compliance.
This Waiver will allow continued operation of CPSES Unit I until relief from ASME Section XI cold shutdown full stroke testing of Residual Heat Removal (RHR) pump discharge check valves 1-8730A and 1-8730B can be requested, reviewed, and granted.
TV Electric's request for the applicable ASME Section XI relief will be transmitted to the NRC via separate correspondence no later than the close of business on January 28, 1991. The specific information requested by the referenced memorandum is provided below.
RLQllIREMENT/RE0 VEST SURVEILLANCE-REQUIREMENT 4.0.5(a) requires inservice testing of ASME Code Class 1, 2, and 3 valves in accordance with Section XI of the ASME Boiler and Pressure Vessel Code and applicable Addenda as required by 10CFR50.55a(g),
except where specific written relief has been granted by the Commission.
Contrary to the above, the cold shutdown full stroke tests of the RHR pump discharge check valves 1-8730A and 1-8730B were not performed within the allowed surveillance interval.
Per SURVEILLANCE REQUI'lEMENT 4.0.3, upon discovery of this missed surveillance, these valves must be successfully tested within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, or the system (RHR trains A&B) declared inoperable, placing CPSES Unit 1 into the applicable action statement of Specification 3.0.3 (requiring immediate shutdown). TV Electric requests a Waiver of Complience from SURVEILLANCE REQUIREMENT 4.0.5(a) for the full stroke test of RHR pump discharge check valves 1-8730A and 1-8730B in order to pursue relief from the NRC for ASME Section XI cold shutdown full scroke testing of these valves.
In parallel, TV Electric will determine whether the ability to full stroke test these valves exists during Cold Shutdown.
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.x TXX-91046-Page 2=of 4 CIRCUMSTANCES:
- The capability of RHR pump discharge check valves 1-8730A and 1-8730B to be
-full stroke tested at cold shutdown has not been confirmed. - Flow to the Reactor Coolant System (RCS) is impractical due to insufficient surge volume to accept full-flow injection during cold shutdown.
The capability of the RHR to
--Reactor Water Storage Tank (RWST) return line:to safely pass the flow necessary to demonstrate satisfactory valve performance during cold shutdown _has not been fully. assessed.
The problem with the RHR system injection into the RCS was recognized previously and relief requests were submitted and approved from cold shutdown full stroke testing of the RHR pump suction check valves-(1-8958A and 1-8958B).
'The current relief establishes full stroke exercising of the RHR pump suction check valves (18958A and 1-89588) to be performed at each refueling outage.
~ Due to an oversight, a similar relief request was not submitted for the RHR pump discharge check valves.
Further, the potential for the RHR to RWST return line to serve _as a viable full flow test path was not recognized. Action to determine operability.was initiated as soon as the inconsistency between the tast procedure and the test requirements was discovered.
COMPENSATORY ACTIONi
- Based on the actual flow testing accomplished previously, satisfactory performance of the check valves has been assured. This testing includes:
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Full flow. testing in January 1990 with the reactor vessel head removed and
'in conjunction with Safety-Injection Flow Balancing and full stroke-tests of other check valves in'the system.
2.
Continued quarterly partial stroke testing utilizing flow through the 3/4 inch test header line.
3: Continued documentation of cold shutdown testing of the RHR Pump Discharge
' Check Valves has showr flows achieved through these check 4alves of between 3500 and 4000 gpm.
Tta latest test was done in November 1990.
An evaluation of:the capability of the RHR to RWST return line to serve-as a viable' full flow test path during cold shutdown will be initiated.
If = it can be determined that-the line will safely pass adequate flow for the tests, the valves will be full stroke tested at the next cold shutdown of sufficient duration.
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-TXX 910467 Page 3 of 4-SAFETY SIGNIFICANCE AND POTENTIAL CONSE0VENCES (PRELIMINARY):
Based on the actual flow testing described above, there is a high le' vel of i
assurance that these check valves were stroked to the full open position. The documented flows measured during cold shutdown testing are not significantly below; the required flow value of 4652 gpm (Technical Specification 4.5.2.h3).
Check valve failure to open is a low probability event.
Failure to identify the RHR to RWST line as a potential full. flow te.st path and to obtain a relief request for the full stroke testing of these discharge check l
valves were oversights. TV Electric has no reason to believe there are=any similar instances of misapplication of ASME Section XI relief requests.
TV Electric will review all current Section XI relief requests and provide the results of this review as part of the Licensee Event Report (LER) required by 10CFR50.73.
Relief for the. discharge check valves is fully justified -pending t
further evaluation of the capability of the RHR to RWST return line and therefore'there is no safety significance or potential consequences associated with this proposed request.
DURATION:
The duration of this waiver-is based on the time necessary-.to pursue relief
- from ASME Section XI cold shutdown full stroke testing of.the RHR pump i
discharge check valves 1-8730A and 1-8730B and in no case will extend beyond February 9, 1911.
SIGNIFICANT HAZARDS CONSIDERATION:
Since the relief is being requested for check valves in the same flow 3ath as other check valves whose performance has been determined to be accepta)le, it-is not expected-that this waiver will result in any significant increase in the probability or consequences of an accident previously evaluated.
The waiver 4
would not create the possibility of a new or different kind of-accident from l
any accident previously evaluated. The-waiver does not involve-a reduction in
- a. margin of safety.
ENVIRONMENTAL CONSE0VENCES:
.The request-only involves a revision to plant documentation. These revisions (and their potential cons _equences are limited to the plant and will not result-in any unplanned _ releases that could cause an impact-on the environment.
TXX-91046 Page 4 of 4 CONCLUSION:
This activity has been reviewed and approved by the Statior Operations Review Committee (SORC).
TV Electric requests that the NRC grant this request for an NRR Waiver of Compliance. The waiver is requested for a curation sufficient to allow processing of the relief reonest from ASME Section XI cold shutdown full stroke testing of the RHR pump ditcharge check v Jves and will not extend beyond February 9, 1991. A respense is requested prior to 2:00pm Central Standard Time, January 26, 1991.
Sincerely,
??hk ry]f William J. Cahill, Jr.
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By
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1 Roger' D. Walker Manager of Nuclear Licensing JDS/gj c - Mr. R. D. Martin, Region IV Resident inspectors, CPSES (3)
Mr. J. W. Clifford, NRR
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