ML19260C023
| ML19260C023 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 12/10/1979 |
| From: | Counsil W, Fee W CONNECTICUT YANKEE ATOMIC POWER CO. |
| To: | Harold Denton, Ziemann D Office of Nuclear Reactor Regulation |
| References | |
| TASK-06-04, TASK-6-4, TASK-RR NUDOCS 7912180248 | |
| Download: ML19260C023 (2) | |
Text
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] CONNECTICUT YANKEE ATOMIC POWER COMPANY 3
BERLIN. C O N N E CTIC U T P
O. SOM 270 H ARTFORD. CONNECTICUT OS'Ot Ta L a smosa s 203-666 6911 December 10, 1979 Docket No. 50-213 Director of Nuclear' Reactor Regulation Attn:
Mr. D. L. Zieman.,, Chief Operating Reactors Branch #2 U. S. Nuclear Regulatory Commdssion Washington, D. C.
20555
References:
(1)
W. G. Counsil lette* to D. L. Ziemann dated January 3,1979.
(2)
D. L. Zicmann letter to W. G. Counsil dated October 23, 1979.
Gentlemen:
Haddam Neck Plant Containment Purging During Normal Operation Your letter of October 23, 1979 identified several generic concerns related to containment purging. After review of our previous correspondence (Reference (1)),
the Staff concluded that further information and an interim commitment was needed from Connecticut Yankee Atomic Power Company (CYAPCO), on one of these items of concern. This letter responds to that iten which is defined as Interim Position 2.b, in your October 23, 1979 letter (Ref erence (2)), i.e., Containment Ventila-tion 1 solation Signals.
Interim Position 2.b requires that CYAPCO, " maintain the containment purge and vent isolation valves closed whenever the reactor is not in the cold shutdown or refueling mode until such time as we can show that: modifications, as necessary, have been made to segregate the containment ventilation isolation signals to ensure that, as a minimum, at least one of the automatic safety injection actuation signals is uninhibited and operable to initiate valve closure when any other isolation signal may be blocked, reset, or overridden".
As acknowledged in Reference (2), Technical Specifications prohibit purging with the 42-inch purge valves unless the plant is in cold shutdown or refueling.
These valves are manually operated. However, venting during operation can be accomplished with the air particulate monitoring line.
1613 042 24F 7912180 C
Venting during operation, through the air particulate monitoring line, requires use of only one vent path and one containment penetration. This penetration is automatically isolated by either of two valves, external to the containment, which are commanded closed by an isolation signal.
Power supplies to these valves ' originate from redundant safeguards power sources.
Isolation signals to the valves (presently from liigh Containment Pressure and by January 1,1980, from SIAS also) cannot be overridden or blocked either at the respective control switches or by overriding the trip signal at any other containment isolation valve. Attempted resetting of the isolation system signal, subsequent to automatic closure of the vent valves, would not cause the valves to move to a non-safe position regardless of their position prior to the actuation signal.
In conjunction with the automatic isolation detailed above, station procedures contain the requirement to close two additional valves in the line from the vent path to the stack upon receipt of a high radiation alarm.
A sample of the vented air is also passed through the containment air monitor and subsequently back to the containment via a separate penetratien which is isolated by two check valves.
This is in addition to the stack monitor which monitors the activity of the vented gases prior to reaching the atmosphere.
CYAPCO does not, therefore, have any potential to block or override vent valve automatic closure operations prior to or while the valves are open.
Consequently, CYAPC0 has concluded that the objectives of the Staff require-ment detailed in Interim Position 2.b of Reference (2) have been fulfilled.
Very truly yours, CONNECTICUT YANKEE ATOMIC POWER COMPANY o
W. G. Cod 6sil Vice President By:
W. F. Fee Vice President 1613 043