ML20210H220
| ML20210H220 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 03/18/1986 |
| From: | Gridley R TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8604030010 | |
| Download: ML20210H220 (3) | |
Text
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e TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 374o1 SN 157B Lookout Place c;
March 18, 1986 BLRD-50-438/85-14 S
BLRD-50-439/85-14 p
U.S. Nuclear Regulatory Commission Region II g
Attn:
Dr. J. Nelson Grace, Regioaal Administrator
~4 101 Marietta Street, NU, ',uite 2900 Atlanta, Georgia 30323
Dear Dr. Grt.ce:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - CONTAINMENT ISOLATION BARRIER DEFICIENCY - BLRD-50-438/85-14, BLRD-50-439/85 FINAL REPORT The subject deficiency was initially reported to NRC-OIE Inspector Al Ignatonis on April 22, 1985 in accordance with 10 CFR 50.55(e) as NCR BLN NEB 8503. This was followed by our interim reports submitted on May 20 and September 19, 1985. Enclosed is our final report.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY
. L. Gridley Manager of Licensing Enclosure cc:
Mr. James Taylor, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8604030010 860318 PDR ADOCK 05000438 S
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An Equal Opportunity Employer 2'7
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ENCLOSURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 CONTAINMENT ISOLATION BARRIER DEFICIENCY BLRD-50-438/85-14 AND BLRD-50-439/85-14 1
NCR BLN NEB 8503 10 CFR 50.55(e)
FINAL REPORT Description of Deficiency The design criteria for the containment isolation and leak testing system, N4-NI-D740, requires at least two containment isolation barriers with the following minimum requirements:
containment isolation valves, piping between these valves, and closed systems used as isolation barriers shall be, as a minimum, ANS Safety Class 2.
The drain line and the compressed air line attached to the fuel transfer tube (penetrations X-37 and X-78) each has only one manual isolation valve within the seismic Category I, Safety Class 2 boundaries.
The deficiency was caused by the code boundaries being shown incorrectly for the spent fuel cooling system on the design criteria diagram (38WO654-NM-01),
which resulted in only one qualified valve providing containment isolation.
Since this was the only deficiency found of this nature, it is considered to be an isolated occurrence of an inadequate design for containment isolation and leak testine.
A review of generic implications for this deficiency has determined that other TVA plants are not affected.
Safety Implications Containment integrity could be degraded because of an isolation barrier deficiency (e.g., valve failure or leak or pipe break) that could result in an uncontrolled radiation release potentially exceeding site boundary radio-logical release limits.
Corrective Action TVA design documents have been reviewed and revised to comply with the code and safety requirements. The design of the drain line and the compressed air line on the transfer tube are now in compliance with TVA design criteria document N4-NI-D740 and ANS Safety Class 2 requirements.
Revised design documents were issued under engineering change notice (ECN) 3295 to implement the physical changes to the drain line and compressed air line. Valves will be installed in tat drain line and compressed air line to provide the required double isolation for the containment. Seismic analysis of the piping has been done to verify that the Category I requirements are met.
All corrective action is scheduled to be complete by six months before fuel load of the applicable unit.
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d 1 New TVA procedure, Office of Engineering Procedure (OEP)-10, which delineates the review process, requires and has established a design vcrification procedure that will ensure an adequate design review is performed and documented.
This design review and verification will.<nsure that drawings of this type receive proper review in the future. The Office o.' Engineering personnel have been trained in this OEP (before the June 29, 1985 effective date.) Since this deficiency is considered an isolated occurrence, no additional action to prevent recurrenco is required.
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