ML20076E666
| ML20076E666 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 07/24/1983 |
| From: | Otoole J CONSOLIDATED EDISON CO. OF NEW YORK, INC. |
| To: | Martin T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20076E661 | List: |
| References | |
| NUDOCS 8308240602 | |
| Download: ML20076E666 (2) | |
Text
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e J hn D. O'Toola v<e Pres +nt Consoldated Edison Company of New York, Inc t
4 trying Place New York, NY 10003 Telephone (212) 460-2533 l
July 24, 1983 Re:
Indian Point Unit No. 2 Docket No. 50-247 s
l Mr. Thomas T. Martin, Director Division of Engineering and Technical Programs j
U.
S. Nuclear Regulatory Commiss on Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 i
Dear Mr. Martin:
This re sponds to your letter of June 24, 1983 which requested an explanation of our actions concerning the air balance between the Primary Auxiliary Building (PAB) and the environment.
This subject was designated as " unresolved" in the report of Inspection No. 50-247/83-13 i
transmitted with the June 24 letter.
l To a large extent, concern with the PAB ventilation system arose as a result of observation of flow conditions by the is ector.
He believed l
these conditions indicated outflow due to certain configuratons of open doors in the PAB and Maintenance & Operations (MO) Building.
Con Edison personnel attempted to reproduce these conditions but were unable to observe anything but inflow to the PAB unless, simultaneously, the large MO Building rollup doors, the MO Building /PAB el 98' equipment doors, PAB i
el 98' roof access door and PAB el 98' fan plenum doors were opened.
We believe that the unlikely coincidence of the above door positioning can 4
be precluded in the future with appropriate administrative controls until modifications can be implemented.
i Since early March, 1982, Con Edison had been taking measures to assure proper control of the air balance within the PAB to prevent the spread of contamination.
The charcoal and HEPA filters in the exhaust plenum of the ventilation exhaust system of the PAB were replaced May 27, 1983.
Following this, an increase in PAB exhaust flow was observed at the vent flow recorder, and a decrease in pressure in the PAB relative to the environment was observed.
8308240602 830815 gDRADOCK 05000247 i
Mr. T. Martin July 20, 1983 The ventilation supply system has been examined and the following actions taken to improve air supply:
1.
Outside louvers were repaired and fully opened.
2.
New roughing filters were installed.
3.
An open seam on the inlet plenum of the supply fan was bolted and caulked to prevent recirculation of air.
4.
Inlet control louvers to the supply fan were adjusted to maximize air flow to the fan.
5.
Broken turning vanes in the supply duct, obstructing flow, were removed and will be replaced.
6.
A properly sized air supply register on the 98 foot elevation was installed.
7.
A study and evaluation of temperature and air flow from each cell in the PAB is underway.
With regard to the double doors between the 98 foot elevation of the PAB and the MO Building, which were of particular concern to the inspector, installation of a personnel access door is planned.
This door will be card reader controlled and the double doors will only be opened by special arran9ement.
Sealing strips will be added to the double doors.
Should you or your staff have any questions, please contact us.
I l
Very truly yours,
/
1
.L
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[A ]4 9 l, & 1'bG John D. O' Tool Vice President CC: Mr. Thomas Foley, Senior Resident Inspector U.
S. Nuclear Regulatory Commission Post Office Box 38 Buchanan, New York 10511
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