ML20244E456
| ML20244E456 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 11/19/1986 |
| From: | Lainas G Office of Nuclear Reactor Regulation |
| To: | Adensam E Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20238A944 | List:
|
| References | |
| FOIA-87-438 TAC-63454, NUDOCS 8611240147 | |
| Download: ML20244E456 (2) | |
Text
i 7
NOV 131E l
]
Docket No. 50-410 DISTRIBUTION.
Docket No. 50-410 PSB r/f MEMORANDUM FOR:
Elinor G. Adensam, Director MHaughey BWR Project Directorate No. 3 Division of BWR Licensing l
FROM:
Gus Lainas, Assistant Director Division of BWR Licensing
SUBJECT:
NINE MILE POINT UNIT 2 SEQUENCE CHANGE IN REFURBISHING MSIVS (TAC # 63454)
In Supplement 5 to the SER dated October 1986, we stated that the four main steam isolation valves (MSIVs), with modified seat spring configurations and recoated tungsten carbide balls, used for secondary containment integrity prior to criticality will have deactivated, unmodified actuatcrs. The licensee, in letters dated November 11 and 17, 1936, now proposes to remove the actuators from the MSIVs which are being used to isolate secondary containment, in order to begin modifications to these actuators while secondary containment is still required.
Upon completion of the modifications the actuators will be reinstalled on the valve bodies.
The MSIVs will remain in the closed position during the entire time that the actuators are being removed, modified, and reinstalled. Also, inadvertent ball movement is not expected while the actuators are not in place because of the high seat spring force on the ball and the large torque required to rotate the ball.
The torque needed to rotate the ball is estimated by the licensee to be a minimum of 50,000 in-lb.
We, therefore, have reasonable assurance that the MSIVs will remain in the closed position, thereby maintaining secondary containment integrity during actuator removal, modifications, and reinstallation.
Our SALP is enclosed, e,
Gus Lainas, Assistant Director Division of BWR Licensing
]
Enclosure:
As stated cc:
R. Houston J. Calvo J. Mulhoun FCGN 7-N 8 y
T. Collins
Contact:
ONC F. J. Witt, NRR I
X29440
- SEE PREVIOUS CONCURRE PAGE l
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j SALP INPUT FROM THE PLANT SYSTEMS BRANCH FOR NINE MILE POINT, UNIT 2 TAC #63454
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l l
I A.
Licensing Activites 1.
Management Involvement in Assuring Quality During the review process, there was early evidence of valve problems at another plant. Management involvement should have prevented the issue from occurring, or occurring so late in the licensing process by getting involved early to fix the problem.
Rating:
3 l
2.
Approach to Resolution of Technical Issues from a Safety Standpoint Timely resolution of issues was experienced during conference calls with knowledgeable applicant personnel.
Rating: 2 s.
Responsiveness to NRC Initiatives:
i Applicant provided technically sound and thorough responses and timely resolution of issues.
l Rating:
1 4.
Staffing (Including Management)
Rating:
N/A 5.
Reporting a,nd Analysis of Reportable Events.
Rating: N/A 6.
Training and Qualification Effectiveness.
Rating:
N/A 7.
Overall Rating for Licensing Activity Functional Area.
Rating:
2
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