ML20065M828
| ML20065M828 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 12/05/1990 |
| From: | Morgan W COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9012110222 | |
| Download: ML20065M828 (2) | |
Text
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[A Ctmmenw:alth Edisen 1400 opus Place Downers Grove, Illinois 60516 December 5,1990 r
U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555
Subject:
LaSalle County Station Units 1 and 2 Secondary Containment Leak Rate Test Schedule to support proposed amendment to the Technical Specifications NBG_DAcheihoA513Za_and 50-374
Reference:
(a) W.E. Morgan (CECO) letters to Dr. T.E. Murley-(NRC), dated July 26,1989 and July 9,1990, LaSalle County Station Units 1 and 2-Proposed Amendment to Technical Specifications for Facility Operating License NPF-11 and NPF-18
Dear Sir:
Specification Amendm)ent to allow continued plant operation "or a period of 12 hou Reference (a transmitted Commonwealth Edison's proposed Technical i
l with the Main Steam Tunnel High Ambient Temperature and High Ventilation System Differential Temperature Trips Bypassed.
Currently, performance of the secondary containment leak rate test at LaSalle Station requires a two unit outage. This is due to the ventilation system configuration in the secondary containment which necessitates shutting off cooling alr flow to the unit main steam tunnels (MST's) during the test.- With the MST cooling air flow shut off, the operating unit will trip on MST high temperatures prior to completion of the leak rate test. Normally the secondary containment leak rate test is performed during a scheduled refuel outage to help minimize the impact of a two unit outage on the Commonwealth Edison system. It is the intention of the station to perform the-secondary containment leak rate test during the time window provided by the next Unit 1 refuel outage as shown in the follovfing schedule. Because access to the secondary containment is restricted during the test, it is desirable to com alete the test as early In the outage as possible to minimize impact on other schedulec outage work.
-UNITS 1 AND 2 FOURTH REFUEL OUTAGE AND SECONDARY CONTAINMENT LEAK RATE TEST SCHEDULE 2/16/91 Start of Unit 1 refuel outage.
2/17/91 Earliest date for completion of the secondary. containment leak rate test.
3/21/91
- Secondary containment leak rate test due date.
4/27/91 Latest date for completion of the secondary containment leak rate test.
4/28/91 End of Unit 1 refuel outage.
8/5/91 Secondary containment leak rate test critical due date.
1/1/92 Start of Unit 2 refuel outage, f99?110222 9012o5 p,'3 4 DOCK 05o00373 PDC A0/7 Ip
l
[
, U.S. Nuclet Regulatory Commission December 5,1990 j
Approval of this relief request by the NRC will allow the performance of the test with either one or both units on line and eliminate the need for a two unit outage, if the proposed amendment is approved prior to the Unit.1 refuel outage the test will probably be completed on the second day of the outage, February 17,1991, with Unit 2 on line. If the proposed amendment is not expected to be approved prior to April 28, 1991, the station will plan a dual unit outage and perform the test as early in the outage as possible. If the proposalis expected to be approved after February 17, 1990, but prior to April 28,1991, the stat on will complete the test as soon as the approvalis received with Unit 2 on line. However, it should be noted that the later in the outage the amendment is approved the more difficult it will be to perform the test.
Performance of the secondary containment leak rate test follawjDg the Unit 1 outage will not be considered either with or without approval of the amendment request. Without approval of the amendment request a dual unit outage would be required during the peak summer season. With approval of the amendment the station could theoretically perform the test with both units in operation. However, the station would probably opt to shutdown at least one unit. The test has never been performed wit 1 a unit in operation and it is the station's opinion that it would not be prudent to perform the test for the first time with both units on line. With one unit shutdown the station staff can carefully monitor the operating unit, ensuring that all parameters respond as anticipated to the temperature transients in the MST.
An expeditious review of this amendment is requested to forgo the necessity of a dual unit outage to perform the required surveillance.
Please direct any questions you may have regarding this matter to this Very truly yours, LU wC 4ttyg i.
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W. E. Morgan Nuclear Licensing Administrator
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