ML19246B691
| ML19246B691 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 06/27/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Proffitt W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| References | |
| NUDOCS 7907180340 | |
| Download: ML19246B691 (2) | |
Text
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UNITED STATES E'
'r NUCLE AR REGUL ATORY COMMISSION I ' $
REGION 11 b,
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101 M ARIE T T A ST. N A SUIT E 3100 AT L ANT A, Gt.ORGI A 30303 6
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g JUN 2 71979 In Reply Refer To:
RII:JP0 50-339, 50-404 50-405 Virginia Electric and Power Company Attn:
W. L. Proffitt Senior Vice President, Power P. O. Box 26666 Richmond, Virginia 23261 Gentlemen:
The enclosed Circular 79-11, is forwarded to you for information.
No ritten response to this Circular is required.
If you require additional information regarding this subject, please contact this office.
S inc e r e l:,,
4 James P. O'Reilly Director
Enclosures:
1.
IE Circular No. 79-11 2.
List of IE Circulars Issued in the Last 12 Months
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34 054 3to 3 ; u7180
JUN 2 71979 9
Virginia Electric and Power Company cc w/ encl:
k'. R. Ca r twri ght, Station Manager Post Office Box 402 Mineral, Virginia 23117 P. G. Perry Senior Resident Engineer Post Office Box 38 Mineral, Virginia 23117 e
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a UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ESTORLEMENT WASHINGTON, D.C.
20555 June 27, 1979 IE Circular No. 79-11 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 appect to ccur at sites where dual reactor units ere being constructed and one primary syster layout is a mittor image of the o.ther.
In 1975 TVA reported a misorleatation problem with the Sequoyah Unit 2 reactor vessel.
Westingh,use 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 Sar Jnafte Unit 2.
Combustion Eng'oeering was the NSSS supplier and Bechte'. provided the A/E service.
Ir 1979 the Texas Utilities Gt.. rating Company reported a reactor vessel suppot* system misorientation at Comanche Peak Unit 2.
Westinghouse supplied the NSS$ Gibbs and Hill was the plant engineer and Brown and Root was the constrtcc7r.
Even though there appears to be minimal safety implications associated with the particular miserientat ion probleras ment ioned, repetition of the same type of errors suggests breakdowns in the design / construction interface relatien-sh ip s t ha t could in turn lead to more significant safety problems.
Corrective preventive action is recommended for the following reasons:
If the interface control system between the NSSS/AE/Conatruction is marginal or ineffective as evidenced b-1e miso-lentation of reactor vessels and their supports, it is poss..e 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 resuyLin ha rdware_ mod if ic at ion s and could cause functional and/or struc jDUPLICATE DOCUMENT m
q operating parameters.
p d cuent eviotSly entered In translating NSSS design inf onnat g
the A/E may make changes to f acilit u
plant. These translations may als' ANO
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