ML20148F269
| ML20148F269 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 03/22/1988 |
| From: | Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | |
| References | |
| TASK-PICM, TASK-SE SECY-88-086A, SECY-88-86A, NUDOCS 8803280106 | |
| Download: ML20148F269 (4) | |
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POLICY ISSUE SECY-88-86A March 22, 1988 (Commission Meeting)
For:
The Commissioners From:
Victor Stello, Jr.
Executive Director for Operations
Subject:
SUPPLEMENTAL INFORMATION ON REMAINING TECHNICAL ISSUES FOR TENNESSEE VALLEY AUTHORITY SEQUOYAH UNIT 2 RESTART
Purpose:
To provide supplemental information on the status of the remaining issues required to be resolved prior to restart of Sequoyah Unit 2.
Background:
In SECY 88-86, dated March 21, 1988, the staff provided a status report on the resolu-tion of Appendix R allegations and informed the Commission that with the exception of a few issues that TVA had determined needed to be resolved prior to restart, the signi.ficant restart issues had been resolved.
The staff was subsequently requested to describe in more detail the remaining technical issues that TVA needed to resolve prior to restart.
The purpose of this paper is to describe those issues.
Discussion:
On March 21, 1988, the staff was advised by TVA that Sequoyah was having difficulty achieving the necessary temperature on as installed resistance temperature detectors in three sections of piping (loopseals) upstritam of the three primary. system safety valves off of the pressurizer.
The temperature required (about 300*F) is necessary to preclude a potential mass-energy flow problem through the safety valves that could damage down-stream piping if the safety valves were required to actuate during plant operation.
This problem was previously identified by
Contact:
Gary G.
Zech, OSP 492-0796 8803200106 880322 Sh,gg p
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TVA.
TVA attempted to fix the problem by adding heat tape and additional insulation.
TVA believed that as the primary system temperature increased during the current heatup, the necessary temperature on the loopseals would be attained.
It has now been determined, however, that additional heat coils and insulation will be required to achieve the necessary temperature at the loopseals.
TVA is currently develop-ing a workplan to install additional heat coils and insulation.
This work will require moving and replacing the missile shield to allow access to the area where the work will be performed.
We are currently discussing with TVA the Technical Specification require-ments that would apply during this work.
Once the work is begun, preliminary estimates indicate that this work will take between 3 to 4 days.
The staff will have better estimates of the time needed after the scope of the effort has been more accurately defined by TVA.
In addition to the issue discussed above, TVA is completing surveillance requirements on individual rod position indication cali-brations; repair of a DC powered room cooler fan in the turbine driven auxiliary feedpump room; shift training involving rolling of the main turbine and stroking of the main feedpump feedwater regulating valves; and repair of a letdown orifice isolation valve which was indicating in the mid-position.
TVA is also obtaining final sign-offs from the plant staff indicating readiness for entry into Mode 2.
These efforts should be ccmpleted by March 23, 1988.
Recommendation:
The Commission authorize the staff to permit TVA to restart Sequoyah Unit 2 once the issue
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regarding achieving the required temperature on the primary system safety relief valve loopseals is resolved and TVA has completed its preparations for entry ipto Mode 2.
yW g[
tor Stello J
g,, Ekecutive Director for Operations
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4 DISTRIBUTION:
Commissioners OGC (H Street)
OI OIA GPA REGIONAL OFFICES EDO OGC (WF)
puscoq'o, UNITED STATES
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W ASHINGTON, D.C. 20655 E
March 22, 1988 OFFICE OF THE SECRETARY MEMORANDUM FOR:
Be'.sy Shelburne, Chief Public Document Roon Sandy Showman,'
no Chief THRU:
Corresponden F n50 Records ~ Branch FROM:
[('
rew Bates, Chief Operations Branch RELEASE OF SECY-88-86A TO THE PUBLIC
SUBJECT:
in the PDR is an advanced copy of Attached for placement SECY-88-86A "Supplemental Information on Remaining Technical Issues for Tennessee Valley Authority Sequoyah Unit 2 Restart."
This document is being placed in the PDR in conjunction with the Commission's upcoming vote on the authorization to the staff to allow the restart of Sequoyah Unit 2.
Attachments:
As stated DCS - 016 Phillips cc L-_