ML20111B290
| ML20111B290 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 02/13/1985 |
| From: | Hufham J TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NCR-3436, NUDOCS 8503130055 | |
| Download: ML20111B290 (2) | |
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TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 374o1 400 Chestnut Street Tower II BLRD-50-438/84-50 BLRD-50-439/84-46 U.S. Nuclear Regulatcry Commission Region II Attn:
Mr. J. Nelson Grace, Regiomi Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
Dear Mr. Grace:
BELLEFONTE NUCLEAR PLANTS UNITS 1 AND 2 - UNAUTHORIZED SUBSTITUTION UNISTRUr ATTACHFENTS FOR SSDs - BLRD-50-438/84-50, BLRD-50-439/84 FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector P. E. Fredrickson on September 17, 1984 in accordance with 10 CFR 50.55(e) as NCR 3436.
Our first interim report was autmitted on October 12, 1984.
Enclosed is our fimi report.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY e
/
W. Hufh anager Enclosure L censing Regulations Mr. James Taylor, Director (Enclosure) cc:
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 l
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388188uBi88$ge S
An Equal Opportunity Cinployer
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EN(LOSURE -
I BELLEFWTE NUCLEAR PLAlff UNITS 1 AND 2 2
UNAUTHORIZED SUBSTITUTION OF WISTRUT ATIACHIENTS FOR SSDs BLRD-50-438/84-50, BLRD-50-439/84-46 NCR 3436 10 CFR 50.55(e)
FINAL REPORT j-Description of Deficiency i
TVA drawing 3GA0059-00-16 R5 allows the substitution of unistrut attachments for 1/2-inch expansion shell anchors (SSD) in three specific base plate designs. All other substitutions must be approved on a case-by-
. case basis. The Bellefonte (BLN) Construction project has been indiscriminately substituting unistrut attachments for 1/2-inch expansion shell anchors. The problem is limited to BLN drawings and procedures and i
does not apply to earlier plants.
The apparent cause of this deficiency was that the requirement for anchor l
substitution has been revised several times during the project life, consequently causing some confusion. TVA's Office of Construction (OC)
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personnel have been under the false impression that a unistrut attachment was superior to a 1/2-inch expansion shell anchor. This led OC personnel to instruct engineering, inspection, and craf tsmet to accept the substitution.
OC " Seismic Support Installation / Inspection" training program formally endorsed this misconception.
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Safety Implications Since unistrut allowables are less than SSD allowables in the longitudinal direction, some substitutions of unistrut attachments for SSD could rwsult in failure of the attachment under design loads. This could adversely affect j
3 safety-related piping supoorts and, consequently, the safety of operations of the plant.
Corrective Action l
As indicated in our first report on this deficiency, the subject anchor substitutions were referred to TVA's Office of Engineering (OE) for evaluation on a case-by-case basis. This evaluation has been completed for all the anchor substitutions and OE has determined that each of the substituted anchors is acceptable for use as-is.
However, it should be noted that the support designs included in~ the scope of the NCR were ITT-Grinnell i
designs. Due to the design procedure employed by ITT-Grinnell, acceptance of j
the subject anchor substitutions was possible. TVA's current design
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j procedures will not allow anchor substitution in as large a nunber of baseplate configurations as was possible with ITT-Grinnell designs..
Consequently, TVA will revise drawing 30A0059-00-17 by February 17, 1985, to more clearly delineate the baseplate configurations that allow substitutions of unistrut attachments for SSDs.
(Note: This is the same drawing as the one referenced above, except that the ntabering was changed and the drawing revised.) BLN OC personnel have revised the " Seismic Support Installations /
Inspection" training module to alert the affected OC personnel to permissible support substitutions.
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