ML20094S310
| ML20094S310 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 04/10/1992 |
| From: | Creel G BALTIMORE GAS & ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9204140339 | |
| Download: ML20094S310 (2) | |
Text
a
, BALTIMORE GAS AND ELECTRIC 1650 CAtNEAT CUFFS PARKWAY LUSBY, MARYLAND 20057-4702 Gromot C, CntEL April 10,1992 v.cc p=c sios '
NUC L E A84 t*4E ROY e
(410)WBO-44&B U. S. Nuchar Regulatory Commission Washington, DC 20555 NITENTION:
Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2; Docket Nos. 50 317 & 54318 Response to improper Operation of Emergency Air Lock Notice of Violation
REFERENCE:
(a)
Letter from hir, C. J Cowgill (NRC) to hir. G. C. Creel (BG&E),
Combined Inspection Nos. 50-317/92-02; 50-318?>2-02, dated h1 arch 12,1992 Gentlemen:
In response to Reference (a), Attachment (1)is provided.
Should you have any further questions regarding this matter, we will be pleased to discuss them with you.
Very truly yours,
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GCC/DWht/dwm/ dim /bjd Attachment cc:
D. A. Brune, Esquire J. E. Silberg, Esquire R. A. Capra, NRC D. G. hicDonald, Jr., N RC T. T. Afartin, NRC P. R. Wilson, NRC R. I. hicLean, DNR J. H. Walter, PSC Q \\
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4 ATI'ACIIMENT (Q IMPROPER OPERATION OF EMERGENCY AIR I.OCK NOTICE Ol' VIOLATION 1.
DESCRilrl' ION ANI) CAUSE OF l' VENT We have reviewed this event and concur that it constituted a valid quality problem. As described in LER 91-007, the failure of the personnel involved in this event to verify that pressure had equalized before opening the door was a contributing cause of this event. Our conclusion is that, although operation of the door is within the bounds of our expectations for skill of the craft, the personnelinvolved in this event had not been made sufficiently aware of the need to allow pressure to equalize across the Emergency Air Lock (EAL) door prior to opening it. Instructions posted at the air lock door and adequate awareness training would have provided an extra measure of defense to prevent this event.
Our design barrier to breaches of coa:ainment integrity via the EAL is its i 4terlock mcchanism, which provides door position indication and prevents operation of one door while the other is unlatched. The primary cause of this event was failure of the itterlock.
This problem is being investigated and the mechanism will be repaired.
An additional item discussed in Reference '(a) concerned our not having initiated an investigation into the human factors implications of this event in a timely manner. An Issue Report (IR) was initiated the day of this event and later reviewed by the Issues Assessment Unit. 3n January 9,1992, as part ofits normal reportability review, Compliance determined the event to be reportabic as an LER in accordance with the requirements of 10 CFR 50.73.
Iluman factors considerations are routinely addressed during LER investigations. The failure to direct a human factors investigation had this event not been reportable was documented as a problem in an IR on January 10,1992.
11.
CORRECTIVE STEPS TAKEN AND RSUll!'S AClllEVEI)
We have pvted signs at the interior and exterior doors and inside the air lock for the Unit 1 and 2 EAL and Personnel Air Lock. These signs caution against opening air lock doors rapidly or before pressure across them is equalized ar '
quire contacting the Control Room if pressure does not equalize within 60 seconds (-
- ve indication that the interlock is L:feated and the other door is open). The posti; these signs is controlled by Calvert Cliffs Instruction CCI-308. Additionally, the signs' ntinued presence at each air lock will be verified on a refueling interval basis.
To ensure personnel are aware of the need to exercise caution when operating air locks, we have added a discussion of the details of this and similar industry events to annual General Orientation Training. The training also includes cautions against opening the doors too quickly or with',t pressure equalizing across them.
III.
CORRECI'IVE STEPS WillCil WII.I. lie TAKEN TO AVOID FURTIIER VIOLATIONS The above actions are sufficient to prevent future incidents of this type.
IV.
DATE W1IEN FULL COMPLIANCE Will,llE ACillEVED Full compliance was achieved when the permanent signs were posted at the air locks.
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