ML20115F740
| ML20115F740 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 03/19/1984 |
| From: | Root R WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| REF-PT21-84, REF-PT21-85-201-000 GO1-84-0073, GO1-84-73, PT21-85-201, PT21-85-201-000, NUDOCS 8504220013 | |
| Download: ML20115F740 (3) | |
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v Washington Public Power Supply System P.O. Box 968 3000 George Washington Way Richland, Washington 99352 (509)372-5000 5
March 19, 1984 G01-84-0073 E'
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Mr. J.B. Martin
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Nuclear Regulatory Commission M"
Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596
Subject:
NUCLEAR PROJECT 1 DOCKET NO. 50-460 REPORTABLE CONDITION 10CFR50.55(e)
RUSKIN BACKDRAFT DAMPER COUNTERWEIGHT ASSEMBLY
Reference:
Telecon, CR Edwards, Supply System to DP Haist, NRC, same subject, dated March 2,1984 In the above referenced telecon the Supply System informed your office of a reportable condition under 10CFR50.55(e).
The enclosed Attachment A provides a statement of the identified condition and our proposed plan for corrective actions.
This letter is our formal notification of this deficiency as a reportable condition under 10CFR50.55(e). We will provide your office with a status report on the progress of the subject condition prior to restarting construction.
If you have an uestions or desire further information, please advise.
R.W. Root, rec or WNP-1 Prog am RWR:TED: cab Attachment cc: TA Mangelsdorf, BPC-861 V Mani, UE&C-897 Document Control Desk, NRC EC Haren, UE&C-895 FDCC-899 ORM-847 0
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ATTACHMENT A WNP1 DOCKET N0. 50-460
- REPORTABLE CONDITION 10CFR50.55(e)
RUSKIN BACKDRAFT DAMPER COUNTERWEIGHT ARM ASSEMBLY
1.0 BACKGROUND
Ruskin Manufacturing Co. notified its customer University Nuclear Systems, Inc. '(UNSI) of a deficiency in some backdraft damper counterweight assemblies, which in some instances do not meet the specified seismic qualification criteria.
The backdraft damper manufacturer, Ruskin Manufacturing Co., has reported-the design deficiency to the NRC under the guidelines of 10CFR Part 21.
University Nuclear Systems, Inc. the HVAC contractor for the Supply System Nuclear Project No.1 has advised the Supply System of the deficiency, and submitted a seismic report and drawings from
'Ruskin Manufacturing, on February 8, 1984.
2.0 DESCRIPTION
OF THE DEFICIENCY Some counterweight assemblies on backdraft dampers supplied for WNP-1 do not meet the seismic criteria outlined in Section 20A of the 9779-216 HVAC Contract Specification. An analysis indicated that under a postulated seismic event, the arm of some of the counter-weight assemblies could break and the backdraft damper would not remain closed.
3.0 ANALYSIS OF SAFETY IMPLICATION Failure of the counterweight assembly will prevent the damper from remaining closed and will cause one or a combination of the following conditions, depending on the particular physical duct layout:
a) Some air will be bypassing the ductwork distribution system through the redundant air handling unit, thus causing the served area temperature setpoint not to be maintained.
b) Some contaminated air may be discharged into non-contaminated ductwork.
c) The air static pressure balance of an area may be upset causing unwanted air migration patterns from potentially contaminated areas into cleaner areas.
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Attachment A Page 2 4.0 CAUSE OF THE DEFICIENCY Ruskin determined that their previous Seismic Report No.1023 calculations for backdraft dampers models CBS-7 and CBS-8 did not include the counterweight arm assemblies and could result in some backdraft dampers not meeting the requirements of the Supply System HVAC Specification 9779-216, Section 20A.
5.0 STATUS OF THE CORRECTIVE ACTION Ruskin Manufacturing has submitted a recommendation for strengthening the counterweight arm assemblies and a revised Seismic Report for the 27 backdraft dampers affected.
None of these dampers are installed and are segregated in UNSI's warehouse at present.
(Bechtel Non-Conformance Report No. BNCR-216-002).
The Supply System's Architect Engineer, United Engineers and Construc-tors,- Inc, has approved Ruskin's revised Seismic Report and Ruskin's fix recommendation.
The additional counterweight arm stiffeners have been manufactured are are currently at Ruskin's manufacturing plant.
Due to the extended construction delay status at WNP-1, the counter-weight arm stiffener installation will be delayed until construction resumes. As a result, an update of this report will be provided at restart of construction.
6.0 ACTIONS TO PREVENT RECURRENCE Implementation of the above corrective actions will assure that there are no further problems with backdraft damper counterweight assemblies.