ML20080Q261

Requests That Open Time Limit on 20-inch Containment Purge & Vent Valves Be Extended to 160 H to Allow for Possibility of Operational Problems During Planned Outage & Any Unscheduled Outages Required Prior to 831210 Shutdown

ML20080Q261
Person / Time
Site:	Pilgrim
Issue date:	10/07/1983
From:	Harrington W BOSTON EDISON CO.
To:	Vassallo D Office of Nuclear Reactor Regulation
References
83-248, NUDOCS 8310120330
Download: ML20080Q261 (2)

Text

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BOSTON EOlsON COMPANY B00 BOYLaTON STRErr BOSTON. MAssACHuarns 02199 WILLIAM D. H ARRINGTON ccation viss passessest GC#K LEAR October 7, 1983 BECo 83-248 Mr. Domenic B. Vassallo, Chief Operating Reactors Branch #2 Division of Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D. C. 20555 License No. DPR-35 Docket No. 50-293 Containment Purge and Vent Valve Open Time Limit

Reference:

Letter from W. D. Harrington, Boston Edison, to D. B. Vassallo, NRC, dated July 28, 1983 (BECo 2.83.200)

Dear Sir:

To prepare for the possible replacement of reactor coolant piping at the Pilgrim Nuclear Power Station during Refueling Outage #7, a short planning outage of approximately 3 days is scheduled to begin October 7,1983. During this plan-ning outage, the as-built configuration of reactor coolant piping susceptible to intergranular stress corrosion cracking (IGSCC) will be studied to allow for l the proper planning of a possible piping replacement operation. This planning outage should ultimately reduce the length of Refueling Outage #7, if the re-placement of reactor coolant piping at Pilgrim indeed becomes necessary.

As so ordered by the NRC in the IGSCC Inspection Order Confirming Shutdown, dated August 26, 1983, a visual examination for leakage of the reactor coolant piping shall be performed during this planning outage because the outage is l

anticipated to last 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or more. To perform this visual examination of reactor coolant piping while it is at operating pressure, purging and venting

! of the drywell atmosphere using the 20-inch containment purge and vent valves I will be required to make the drywell habitable while the reactor is still at low power. Low power must be maintained so that the reactor can be kept at i

operating pressure during the visual examination.

In addition to the above, the 20-inch containment purge and vent valves will be required to be opened during startup to inert the drywell after the piping in-spection at a reactor coolant pressure of 600 psi. The use of these valves is required at each plant " .ctup because Technical Specification 3.7.A.5.b )jJpf requires that the drywell be inerted within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of placing the reactor in the Run mode. 7 8310120330 831007 PDR ADOCK 05000293 P PDR

BOSTON EZCON COMPANY Mr. Domenic B. Vassallo, Chief Page 2 As requested by the referenced letter,and subsequently granted by Mr. Ken Eccleston of the NRC in a telephone conversation on July 29, 1983, our commitment to limit the open time of the 20-inch containment purge and vent valves during power opera-tion to 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> per year was increased to 130 hours0.0015 days <br />0.0361 hours <br />2.149471e-4 weeks <br />4.9465e-5 months <br /> per year, for the year 1983 only. At the present, before the start of this planning outage, these valves have been opened a total of 105 hours0.00122 days <br />0.0292 hours <br />1.736111e-4 weeks <br />3.99525e-5 months <br /> during power operation in 1983. The purging and venting operations described above for the scheduled planning outage will re-quire approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of add uional purge and vent valve open time during power operation, if no problems during shutdown or startup are encountered. Thus, the total accumulated purge and vent valve open time after this planning outage is projected to be approximately 129 hours0.00149 days <br />0.0358 hours <br />2.132936e-4 weeks <br />4.90845e-5 months <br />, which is within the current valve open time limit of 130 hours0.0015 days <br />0.0361 hours <br />2.149471e-4 weeks <br />4.9465e-5 months <br /> in 1983.

To allow for the possibility of operational problems that may require exceeding the 130 hour0.0015 days <br />0.0361 hours <br />2.149471e-4 weeks <br />4.9465e-5 months <br /> open time limit during this planning outage and for any unscheduled outages that may be required prior to shutdown for refueling on December 10, 1983, it is requested that.the open time limit on the 20-inch containment purge and vent valves be extended to 160 hours0.00185 days <br />0.0444 hours <br />2.645503e-4 weeks <br />6.088e-5 months <br />, for the year 1983 only. It remains our goal to minimize the time that these valves are open to reduce the possibility that these valves will be required to close during a postulated LOCA event..

Very truly yours,

/4/'h DMV/kc

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