ML19224D650
| ML19224D650 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 07/02/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Gerstner W ILLINOIS POWER CO. |
| References | |
| NUDOCS 7907130270 | |
| Download: ML19224D650 (1) | |
Text
[s oq'o
~} l C o arc UNITED STATES
! ', 3,, g(',%
NUCLEAR REGULATORY COMMISSION
$.7
'-'//. E REGION lil o,
[
799 ROOSEVELT ROAD
'%s [
GLEN ELLYN ILLINOls 60137 JUL 2 1979 Docket No. 50-461 Docket No. 50-462 Illinois Power Company ATTN:
Mr. W. C. Gerstner Executive Vice President 500 South 27'h Street Decatur, IL 62525 Gentlemen:
The enclosed IE Bulletin No. 79-;4 is forwarded to you for action.
Written responses are required.
If you desire additional information regarding this matter, please contact this office.
Sincerely, C1. _. m bg kamesG.Keppler Director
Enclosure:
IE Bulletin No. 79-14 cc w/ encl:
Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR
.NSIC
/ TIC Mr. Dean Hansell, Office of Assistant Attorney General 369 006
! \\:
7907130M/{
J
/
U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT REGION III July 2, 1979 IE Bulletin No. 79-14 SEISMIC ANALYSES FOR AS-BUILT SAFETY-RELATED PIPING SYSTEMS Description of Circumstances:
Recenty twa issues were identified which can cause seismic analysis of safety-related piping systems to yield nonconservative results.
One issue in"olved d gebcaic summation of loads in some seismic analyses. This was addressed it show cause orders for Beaver Valley, Fitzpatrick, Maine Yankee and Surry.
It was also addressed in IE Bulletin 79-07 which was sent to all power reactor licensees.
The other issue involves the accuracy of the information input for seismic analyses.
In this regard, several potentially unconaervative factors were discovered and subsequently addressed in IE Bulletin 79-02 (pipe supports) and 79-04 (valve weights). During resolution of these concerns, inspection by IE and by licensees of the as-built configuration of several piping systems revealed a number of nonconformances to design documents which could potentially affect the validity of seismic analyses. Nonconformances are identified in Appendix A to this bulletin.
Because apparently significant non-conformances to design documents have occurred in a number of plants, this issue is generic.
The staff has determined, where design specifications and drawings are used to obtain input information for seismic ana l ysis of safety-related piping systems, that it is essential for these documents to reflect as-built con-figurations. Where subsequent use, damage or modifications affect the con-dition or configuration of safety-related piping systems as described in documents from which seismic analysis input information was obtained, the licensee must consider the need to re-evaleste the seismic analyses to con-sider the as-built configuration.
369 007 P
- DUPLICATE DOCUMENT Entire document previously entered into system under:
ANO 7 9 O 7 O h O 'W[
0 No. of pages:
f
_.py 7-
=
r y
g up _ - -___ % mmeesm.
w WM hw+ L '* M*
" ' ' * * ' ' ^