ML19225A077
| ML19225A077 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 06/27/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Eric Turner HOUSTON LIGHTING & POWER CO. |
| References | |
| NUDOCS 7907180252 | |
| Download: ML19225A077 (1) | |
Text
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9 UNITED STATES
$. 'f,., 7/,7, E ' hl-NUCLEAR REGULATORY COMMISSION E$
REGION IV
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611 RYAN PLAZA DRIVE, SulTE 1000 0,
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AR LINGTON, TEXAS 76012 June 27, 1979 In Reply Refer To:
RIV Docket Nos. 50-498/IE Circular No. 79-11 50-499/IE Circular No. 79-11 11ouston Lighting & Power Company ATTN:
Mr. E. A. Turner, Vice President Power Plant Construction and Technical Services Post Office Box 1700 Houston, Texas 77001 Gentlenen:
The enclosed Circular 79-11, is forwarded to you.for information.
No written response to this Circular is required.
If you require additional information regarding this subject, please contact this office.
Sincerely, Yb Karl V. Seyf ri '
Director
Enclosures:
1.
IE Circular No. 79-11 2.
List of IE Circulars Issued in the Last 12 Fanths
\\
7007180 AM
UNITED STATES NUCLEAR REGULATORY COT!ISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Circular No. 79-11 Date. June 27, 1979 Page 1 of 2 DESIGN / CONSTRUCTION INTERFACE PROBLEM Description of Circumstances:
Apparent inadequate communication between nuclear steam supply system (NSSS),
architect / engineer (A/E) and constructors have resulted in several cases where reactor vessels or the supports have been misoriented. The misorienta-tion problems appear to occur at sites where dual reactor units are being constructed and one primary systet layout is a mirror image of the other.
In 1975 TVA reported a misorientation problem wi'.h the Sequoyah Unit 2 reactor vessel. Westinghouse was the NSSS supplier and TVA provided their own A/E service.
In 1977 the Southern California Edison Company reported a reactor vessel misorientation at San Onofre Unit 2.
Combustion Engineering was the NSSS supplier and Bechtel,provided the A/E service.
In 1979 the Texas Utilities Generating Company reported a reactor vessel support system misorientation at Comanche Peak Unit 2.
Westinghouse supplied the NSSS, Gibbs and Hill was the plant engineer and Brown and Root was the constructor.
Even though there appears to be minimal safety implications associated with the particular misorientation problems mentioned, repetition of the same type of errors suggests breakdowns in the design / construction interface relation-ships that could in turn lead to nore significant safety problems.
Corrective preventive action is recommended fcr the following reasons:
If the interface control system between the NSSS/AE/ Construction is marginal or ineffective as evidenced by the misorientation of reactor vessels and their supports, it is possible that other safety related equipment may also be misoriented and/or mislocated.
In some cases the errors may not be as obvious as a misoriented reactor vessel.
This type of error can and has '-
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i could cause functional and/or s f DUPLICATE DOCUMENT operating parameters.
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" Entire document previously entered In translating NSSS design infc{ into system under:
theA/Emaymakechangestofacj i
plant.
These translations may ANO 79 OM 00 / %
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hh2 No. of pages:
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7906200176
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