ML20093N152
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ji H. Etherington, Chainen
.jJ B&W Water Reactors Subcomittee.
f ii' SAFE SHUTDOWN BORATION CAPABILITY t-
' { h-p According to the attached letter from Consumers Power Company, it took "an extensive review" of the Midland shutdown boration capability, to 6
discover, on October 1,1979, that the Midland design does-not permit achieving and maintaining a 1%Ak/k shutdown margin with safety grade equipment assuming "a most restrictive condition and the control rod e
jT of highest worth stuck out of the core."
p 33 I suggest that the circumstances surrounding this discovery be re-h viewed by the B&W Water Reactors Subcomittee to especially explore Q
proposed fixes, but also to explore whether a similar extensive re-t:
view should be performed on other B&W reactors.
If you concur, please L-let me know and I will take the necessary steps to arrange a meeting y
of the Subcomittee.
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.,.g' Senior Staff Engineer Ragnwald Muller u
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Attachment:
Consumers Power Company 1tr.
Howe-283-79, of Oct. 31, 1979 s, _
if' cc: ACRS i.
Technical Staff
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s w amaa-5 at PRELIMINARY NOTIFICATION
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May 4, 1979
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-r PRELIMINARY NOTIFICATION OF EVEh7 OR UNUSUAL OCCURRENCE--PNO-79-101 This preliminary notification constitutes EARLY notice _ of_ an event of t *.
POSSIBLE safety or public interest significance. The information presented is as initially received without verification _or_ evaluation I-and is basically all that is known by IE staff on this date.
f1 Facility:
Consumers Power Company; Midland, Units 1 and 2 f'
Midland, Richigan (DN 50-329 and DN 50-330) l' Subj ect:
CUT WIRES AT HIDLAND CONSTRUCTION SITE jy Consumers Power notified the resident inspect.or that approximately 20 electrical wires were apparently cut intentionally in four safety I
and non-safety related panels in the control room at the Midland Q
site.
It appeared the wires were cut using electrical pliers.
In f
addition, glass was found broken in six electrical relay covers.
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The damage was found on the morning of May 3 by a Bechtel electrical
/j' foreman. The control room is not normally manned during the night 7
shift. The licensee is currently reviewing the problem. No significant D
labor disputes have occurred recently.
tY
}y Region III will monitor the licensee's investigation of the matter.
jg Independent investigation by the NRC will be conducted if warranted.
3 No press release is planned by the licensee or the NRC at this time t
The State of Michigan is being notified.
The resident inspector was notified of this problem at 1245 hours0.0144 days <br />0.346 hours <br />0.00206 weeks <br />4.737225e-4 months <br /> on May 3, 1979, by consumers Power Company.
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_C_onta ct : JBHenderson, IE, 27551; GWReinmuth, IE, 27551 Distribution:
Transanitted IT Dt @/I Chairman kendrie Commissioner Bradford S. J. Chilk, SECY Coarissioner Kennedy Consnissioner Ahearne C. C. Kammerer, CA Comar.1:sioner Gilinsky (For Distribution)
Transmitted: MNBB _
P. Bldg J. G. Davis, IE y
L. V. Gossick, EDO E. R. Denton, NRR Region
't H. L. Ornstein, EDO R. C. DeYoung, NRR g
J. J. Fouchard, PA R. J. Mattson, NRR M N. M. Haller, MPA V. Stello, NRR
/(MAIL)
R. G. Ryan, OSP R..S. Boyd, NRR J. J. Cummings, OIA H. K. Shapar, ELD S Bldg R. Minogue, SD S
ev e RES p
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Company Senior Vice hesident Generes offices: 1945 West Pernett need, Jackson, MicNeon 4e201. (s1717se4453 October 31, 1979 Howe-283-79 Mr J G Keppler, Regional Director Office of Inspection and Enforcement US Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 6013T MIDLAND NUCI2AR PIAIFf UNIT NO 1, DOCKET No 50-329 UNIT NO 2, DOCKET NO 50-330 SAFE SHUIDOWN BORATION CAPABILITY In accordance with the requirements of 10 CFR 50 55(e), this letter constitutes an interim report concerninc a potentially unsafe situation originally reported by a telephone call frca B U MarguGlio, CPCo QA-PILC, to R Cook, NRC Resident Inspector, on October 2,~ lW9 On October 1,1W9, Consumers Power Company received written notification from Dabcock ts Wilcox that the present Midland design does not permit achievin5 and maintaining a 1% o k/k shutdown margin with safety grade.
equipment assuming a most restrictive core condition and _the control rod of highest worth stuck out of the core. This report resulted after an extensive review of the Midland shutdown boration espability. At present, several
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design changes, including hardware modifications and changes to boron i
concentration, are under consideration as remedies for this situation.
Another report, either interim or final, will be sent on or before January 29, 1980.
&-- ^Y GR/1r CC: Director of Office of Inspection and Enforcement h[6 9 l
Att: MrVictorStello,IENRC(15)
Director of Office of Management
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Information and Program Control, USERC (1)
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