ML20076E551
| ML20076E551 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 08/12/1983 |
| From: | Lempges T NIAGARA MOHAWK POWER CORP. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20076E544 | List: |
| References | |
| NUDOCS 8308240528 | |
| Download: ML20076E551 (3) | |
Text
I M V NIAGARA R UMOHAWK NIAGARA MOHAWK POWER CORPORATION /300 ER;E BOULEVARD WEST, SYEAcuSE, N.Y.13202/ TELEPHONE (315) 474-1511 August 12, 1983 Mr. R. W. Starostecki, Director Division of Project and Resident Programs U.S. Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406 4
Re: Ni,e Mile Point Unit 1 Docket No. 50-220 DPR-63
Dear Mr. Starostecki:
Your letter of July 13, 1983 set forth action items regarding valve operators installed in the containment spray test / alternate torus cooling line. The attachment to this letter provides information relative to the steps taken to implement the required action items.
Very truly yours, T.
pg Vice President Nuclear Generation TEL/MTG:djm Attachment 8308240528 830822 PDR ADOCK 05000220 0
RESPONSE TO CONFIRMATORY ACTION LETTER 83-07 Action Item 1: Remove the air operators from two valves in one containment spray system to restore it to its original configuration, to assure seismic operability of one system, by July 12, 1983.
Response: On July 11, 1983, the air operators on two valves, 80-44 and 80-45, were remoted. At that time, these valves were effectively closed (removal of the air operators resulted in not being able to open the valve).
In addition, strongbacks were installed on these valves to maintain them in the closed position. Since the original handwheels and original shafts were not available, a modifieri configuration was later added to the valves to allow for manual operation.
Prior to installation, an evaluation was performed which showed that the modified configuration would not cause any loads, including seismic, significantly greater than the original manual handwheel configuration. This action essured the seismic operability of their associated containment spray system.
Action Item 2: Perform a seismic analysis of the containment spray test / alternate torus cooling lines affected by the installation of the subject valve operators and install necessary seismic supports prior to reinstallation of the valve operators.
Response,: Seismic calculations on the containment spray test / alternate torus cooling lines containing valves 80-40, 80-44 and 80-45 were performed, by a consultant, in accordance with the criteria outlined in the Niagara Mohawk Final Safety Analysis Report for Nine Mile Point Unit 1.
In addition, preliminary calculations were performed on valves 80-41 and 80-118 by Niagara Mohawk. A final report was prepared by the consultant summarizing both calculations.
This report was reviewed by Niagara Mohawk.
Final calculations on valves 80-41 and 80-118 are currently being compiled. Any significant changes affecting the final report, noted during assembly of the final calculations will be forwarded to your staff.
From the above analyses, it was concluded that the stresses in the containment spray piping and valve bodies due to the combination of normal and seismic loads, and considering the effects of the addition of the valve operators, are within Final Safety Analysis Report allowable limits without additional seismic support.
On this basis, it is our intent to reinstall the valve operators without any n'odification to the piping system, valves or their supports, upon completion of our final calculations.
Action Item 3,:
If the action described in 2 above is not completed by July 19, 1983, the valve operators from the remaining two valves will be removed until that action is complete to assure compliance with Technical Specification Section 3.3.7.
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e Response: On July 12, 1983, the remaining two air operators, one each on valve 80-40 and 80-41, were removed. The same modified configuration was installed on these valves for manual operation as described in our response to Action Item 1.
This action along with the action described in response to Action Item 1 resulted in both the containment spray systems being considered operable. Therefore, compliance to Technical Specification Section 3.3.7 was assured.
Action Item 4: Conduct a review of plant modifications completed from commencement of the 1981 refueling outage to date which involved seismic considerations and assure that the analysis methods used were correct and the Modifications comply with your applicable Safety Analysis. This review will be completed by August 12, 1983.
Response: A record search was initiated for the purpose of identifying modifications which have been completed during and since the 1981 refueling outage. Each modification file is being reviewed to verify completion date.
To date, approximately 140 modifications have been identified as having been completed during the time frame of interest.
Following identification of the appropriate modifications a review will be performed to select those modifications that required seismic considerations.
The selection process will consist of an initial screening of obvious non-seismic modifications. The remaining cpplicable modifications will then be reviewed to determine if seismic analyses should have been performed.
Finally, after modifications which required seismic design have been identified, the modification package will be reviewed to determine that analyses have been completed in accordance with the criteria contained in the Final Safety Analysis Report.
To assure that the review is performed independently, a consultant not previously involved in modifications at Nine Mile Point Unit I will be retained. The specific consultant will De familiar with Nine Mile Point Unit I and the applicable seismic criteria.
In order to complete the modification review program as outlined above, additional time will be required. Our current schedule is for completion of this review program by November 30, 1983. At that time, the results of the program and remedial action, if any, will be provided.
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