ML20150B420
| ML20150B420 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 03/11/1988 |
| From: | Gridley R TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| NUDOCS 8803160378 | |
| Download: ML20150B420 (4) | |
Text
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TENNESSEE VALLEY AUTHORITY CHATTANOOGA, TENNESSEE 37401 SN 1578 Lookout Place MAR 111988 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Hashington, D.C.
20555 Gentlemen:
In the Matter of
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Docket Nos. 50-259 Tennessee Valley Authority
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50-260
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50-296 BROWNS FERRY NUCLEAR PLANT UNITS 1, 2, AND 3 - NRC INSPECTION REPORT NOS. 50-259/87-20, 50-260/87-20, AND 50-296/87 SUPPLEMENTAL RESPONSE TO DEVIATION This letter is to provide TVA's supplemental response to the letter from G. G. Zech to S. A. White dated July 8, 1987, which transmitted the subject report.
This report cited TVA with one deviation.
In TVA's response letter from J. A. Domer dated August 6, 1987, TVA committed to having the main control room panels modified by February 27, 1988.
TVA has since made progress toward completion of this project by completing our redesign for panel mounting, revising the drawings to show the correct anchorage requirements, and subsequently issuing the drawings to the field for work. Additionally, the workplans have been written, approved, and they are ready for work. The modification work on the panels has been delayed because of a naterial restraint problem.
This will require a change in our date of full compliance to May 6, 1988. provides TVA's description of corrective actions and the new completion date. A list of commitments is provided in enclosure 2.
He do not recognize any other items described herein as commitments.
If you have any questions, please telephone Clark 5. Madden at (205) 729-2049.
Very truly yours, TENNESSEE VALLEY AUTHORITY
[\\\\/
R. Gridl'e, Director
'D Nuclear Licensing and,
Regulatory Affairs Enclosures cc: See page 2 ol 8803160378 880311 PDR ADOCK 05000259
/f DCD An Equal opportunity Employer g
U.S. Nuclear Regulatory Commission g j ggg cc (Enclosure):
Mr. K. P. Barr, Acting Assistant Director for Inspection Programs TVA Projects Division U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NH, Suite 2900 Atlanta, Georgia 30323 Mr. G. G. Zech, Assistant Director for Projects TVA Projects Division U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Mar.yland 20852 Browns Ferry Resident Inspector Browns Ferry Nuclear Plant Route 12, P.O. Box 637 Athens, Alabama 35611
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ENCLOSURE 1 RESPONSE TO NRC INSPECTION REPORT NOS. 50-259/87-20, 50-260/87-20 AND 50-296/87-20 DATED JULY 8, 1987 ITEM Section 7.2.5.2 of the Browns Ferry Plant Final Safety Analysis Report (FSAR) states that the seismic capability of certain safety systems, including control room panels, were demonstrated by vibration testing of the representative assemblies.
The FSAR further states that during testing, the panels were mounted on the shaker table in a manner similar to the service mounting.
Contrary to the above, main control room vertical bench board type control panels and freestanding vertical control panels were found to be mounted in a manner not consistent with the seismic qualification with no similarity analysis to justify the differences. NEDO-10678, "Seismic Qualification of Class 1 Electric Equipment," documents that the panels were to be floor mounted using 5/8 inch bolts in all mounting holes. Mechanical layout drawing 47W605-3 shows the as-constructed mounting details of these panels to be "tack welded at intervals to fasten in place."
1.
Corrective Steps Which Have Been Taken and Results Achieved The anchorage details for the control room panels specified on the mechanical layout drawing 47W605-3 issued on May 1, 1968, did not adequately specify the anchorage details to ensure installation similar to that required by the qualification test.
TVA's engineering procedures now require engineering drawings to clearly specify the anchorage requirements which are documented
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by appropriate engineering evaluations. Also, TVA has since improved the quality inspection program to require a more rigid inspection of the l
anchorage installation and to provide the proper documentation certifying the proper installation.
TVA has performed a seismic review of the main control room vertical bench board panels and freestanding control panels to determine the appropriate mounting arrangement.
Following this analysis, the engineering drawings were revised to reflect the correct anchorage requirements.
2.
Corrective Steps Which Will Be Taken to Avoid Further Deviation The subject panels will be modified to meet the design requirements.
l The design change, together with the modification, will bring the seismic qualification of the subject panels into compliance with FSAR Section 7.2.5.2.
3.
Date of Full Compliance l
May 6, 1988.
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e ENCLOSURE 2 RESPONSE TO NRC INSPECTION REPORT NOS. 50-259/87-20, 50-260/87-20, AND 50-296/87-20 DATED JULY 8, 1987 List of commitments made in enclosure 1.
1.
The engineering drawings have been revised to reflect the correct anchorage requirements.
(Complete) 2.
The modifications of the main control room panels will be completed by May 6, 1988.
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