ML20128B704
| ML20128B704 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 06/25/1985 |
| From: | Linder F DAIRYLAND POWER COOPERATIVE |
| To: | Zwolinski J Office of Nuclear Reactor Regulation |
| References | |
| TASK-2.E.4.2, TASK-TM LAC-10968, NUDOCS 8507030322 | |
| Download: ML20128B704 (2) | |
Text
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D DA/RYLAND h
COOPERAT/VE
- P.O. BOX 817 2615 EAST AV SOUTH. LA CROSSE. WISCONSIN 54601 (608) 788 4 000 June 25, 1985 In reply, please refer to LAC-10968 DOCKET NO. 50-409 Director of Nuclear Reactor Regulation Attn:
Mr. John Zwolinski Operating Branch #5 Division of Operating Reactors U. S. Nuclear Regulatory Commission Washington, DC 20555
SUBJECT:
DAIRYLAND POWER COOPERATIVE LA CRSSE BOILING WATER REACTOR (LACBWR)
P"
[0NAL OPERATING LICENSE NO. DPR-45 EM II.E.4.2.6 (L
aINMENT ISOLATION) OPERABLE VALVES
REFERENCES:
(1) NRC Letter, Zwolinski to Linder, dated January 15, 1985.
(2) DPC Letter, Linder to Zwolinski, LAC-10598, dated February 27, 1985.
Dear Mr. Zwolinski:
Reference 1 contained the NRC Safety Evaluation on the operability of the 4-inch vent header isolation valves.
It requested information and proposed Technical Specifications on the vent header internal valve closure time.
Reference 2 provided the requested information and stated that since LACBWR Technical Specifications already require surveillance testing of the valve and measurement of its closure time, an additional specification establishing a time limit was not necessary. The procedure implementing the required surveillance test has been modified to specify the closure time limit. Also, if a dynamic test is successfully conducted demonstrating valve closure at 52 psig, the closure time limit would not be needed. Therefore, it would not be efficient to change the Technical Specifications.
The NRC has asked (telecon, Dudley (NRC) and Goodman (DPC), May 16, 1985) whether a dynamic test of the vent header internal valve will be conducted at the completion of the next scheduled Integrated Leak Rate Test (ILRT). At this time, DPC plans to attempt to perform a dynamic test of the vent header valves following the next ILRT.
If a dynamic test is not conducted, DPC will propose a Technical Specification which establishes a closure time limit for
'the vent header internal valve.
Two items covered in Reference 1 are in need of clarification. First, the WPl.6.8 1 8507030322 950625 y
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Mr. Jchn Zwolinzki, Chief June 25, 1985 Operating Branch #5 LAC-10968 manufacturer of the vent header external valve, 55-25-004, is Black, Sivalls and Bryson, Inc.
The other item deals with the procedural requirements covering closure of the vent header external valve. The major primary leak procedure and the alarm response procedure for high Containment Building activity require the vent I
header external valve to be closed. The procedures do not stipulate only when I-the pressure in containment is less' than 40 psig. The reason for this is
.two-fold.
First, the containment pressure is predicted to be above 40 psig for only a short period of time. Therefore, the disadvantages of further complicating the procedures by the addition of the stipulation outweigh any advantage. It is highly unlikely that the operators would be turning the valve control switch during that short period of time (from 6-20 seconds following a recirculation line break). Secondly, it is known that the valve can close under flow conditions when the containment pressure is 40 psig. It is not known whether it will close at higher containment pressure. Therefore, even if.the pressure is above 40 psig, an attempt should be made to close the valve and terminate the release. For both of these reasons, the major primary leak procedure requires the operator to close the vent header external valve without specifying a containment pressure range for conduct of that step.
If there are any questions, please contact us.
Yours truly, D IRYLAND POWER COOPERATIVE Wf
$6 E
ank Linder, General Manager FL:LSG:sks cc: Jamec G. Keppler, Region III NRC Recident Inspector Richard Dudley, LACBWR Project Manager l
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