ML19220B938
| ML19220B938 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/06/1977 |
| From: | Arnold R Metropolitan Edison Co |
| To: | O'Reilly J NRC Office of Inspection & Enforcement (IE Region I) |
| Shared Package | |
| ML19220B931 | List: |
| References | |
| NUDOCS 7904270677 | |
| Download: ML19220B938 (1) | |
Text
OHC7
[
W w
l,M = % w
.,/=
^
METROPOLITAN EDISON COMPANY sussmuar ceceneszuurucurtunesccspanancs
/
' CST CFFICS BOX 542 REACING, PENNSYLVANIA 19603 TELEPHONE 215 - 929-t601 May 6,1977 cqL c611 Mr. J. P. O'Reilly, Director U. S. Nuclear Regulatory Co dssion Office of Inspection & Enforcenent Regien I 631 Park Avenue King of Prussia, Pennsylvania 19406
Dear Sir:
Three Mile Island Nuclear Station Unit 2 ("DfI-2)
License No. CPPR-66 Docket No. 50-320 Seis=ic I Block Walls
(
April 8, 1977, Mr. L. Narrev of'your office was verbally notified of a situation which Metropolitan Edison Co=pany considered to be reportable to the require =ents of 10 CPR 50.55(e). This letter constitutes the required thirty-day follow-up letter.
Descrirtion As a result of an investigation conducted by the Engineer, it was discovered that certain block walls which had been designated Seis=le I had not been constructed in accordance with approved drawings. Specifically, there is evidence of:
ince=plete filling or total lack of grout in some block cavities, devel rods from the ceiling are rd.ssing, lapping of reinforcing bar is not continuous, and in so=e areas, no re:mming bar was installed.
Since these valls were not classified as being within QA/QC scope, there were no in-process inspections conducted during the installation.
Anal rsis of Safety I=elications The block valls in question vere provided as fire valls around the stairvells and elevators of the Reactor 3u11 ding and the Auxiliary Euilding. They provide no required structural integrity to either structure and were designed as Seis=ic I to prevent their falling onto nearby safety related equipment and possibly da= aging or otherwise rendering the equipment useless. Due to the fact that all safety related equip =ent has physical separation fro = its redundant counterpart, de is highly i= probable thst both safety related redundant co=ponents would be se by having a vall collapse. Therefore, this incident would not have pre-ented the safe shutdown of the unit's reactor. For this reason, there vould have been no effect on the health or safety of the plant staff or the public.
79042706M g4 072
s 2-Mrf 6, 1977 fr. J. P. O'Reilly GQL 0611 Corrective Action A detailed investigation of all Seismic I block valls was conducted by the Construction Manager to determine the full extent of this deficiency.
This investigation has revealed that only the reinforced block walls around the elevators and stairvells in the Reactor Building and Auxiliary Building are in this condition.
The results of this study with attendant sketches deta4Hrg the "as installed" valls has been submitted to the Engineer. This infor=ation is presently being evaluated by the Engineer who vill issue instructions to the field specifying all appropriate remedial actions, if required. These instructions are expected to be issued to the field by May 15, 1977.
Infor=ation and docu=entation associated with this incident will be available at the site for your review.
Very truly yours, I
R. C. Arnold RCA:JES:rk cc: Dr. Ernst Volgenau Office of Inspection & Enforca-a_t U. S. Nuclear Regulatory Co:::=1ssion
'Jashington, D. C. 20555 e
P 84-073