United States Nuclear Regulatory Commission - Protecting People and the Environment

NOED-02-1-001 - Calvert Cliffs (Constellation Nuclear)

January 31, 2002

Mr. Charles H. Cruse
Vice President - Constellation Nuclear
Calvert Cliffs Nuclear Power Plant, Inc.
1650 Calvert Cliffs Parkway
Lusby, MD 20657-4702

SUBJECT: NOTICE OF ENFORCEMENT DISCRETION FOR CONSTELLATION NUCLEAR REGARDING CALVERT CLIFFS UNIT 2 [NOED No. 2002-01-01]

By letter dated January 29, 2002, you requested that the NRC exercise discretion to not enforce compliance with the actions required by Technical Specification (TS) 3.8.1, "A.C. Sources - Operating," for Calvert Cliffs Unit 2. Your letter documented information previously discussed with the NRC in a telephone conference at 10:00 p.m., on January 26, 2002. The principal NRC staff members who participated in that telephone conference included:

NRC Region I Staff
- Hubert Miller, Regional Administrator
- A. Randolph Blough, Director, Division of Reactor Projects (DRP)
- Richard Crlenjak, Deputy Director, Division of Reactor Safety (DRS)
- Michele Evans, Branch Chief, DRP Branch 1
- James Trapp, Senior Reactor Analyst
- David Beaulieu, Senior Resident Inspector

NRC Headquarters Staff
- Elinor Adensam, Director - PD-I, Division of Licensing Project Management (DLPM)
- Joel Munday, Section Chief, PD-I
- Donna Skay, Calvert Cliffs Project Manager, DLPM
- Peter Wilson, Senior Reactor Analyst, Probabilistic Safety Assessment Branch
- Om Chopra, Senior Electrical Engineer, Electrical and Instrumentation and Control Branch

You stated that on January 27, 2002, at 3:00 a.m., Calvert Cliffs Unit 2 would not be in compliance with TS 3.8.1 due to the inoperability of the No. 2A emergency diesel generator (EDG) and thus would be required to enter the hot shutdown condition by 9:00 a.m., on January 27, 2002. You requested that a Notice of Enforcement Discretion (NOED) be issued pursuant to the NRC's policy regarding exercise of discretion for an operating facility, set out in Section VII.C, of the "General Statement of Policy and Procedures for NRC Enforcement Actions" (Enforcement Policy), NUREG-1600, and be effective for 6 days, ending at 3:00 a.m., on February 2, 2002. This letter documents our telephone conversation at 10:00 p.m., on January 26, 2002, during which we orally issued this NOED. We understand that the condition causing the need for this NOED was corrected by you and thus you exited from TS 3.8.1 and from this NOED on January 31, 2002, at 2:30 p.m.

Your staff requested this NOED following problems identified during a biennial inspection of the 2A EDG. Specifically, unexpected wear was noted on the flexible drive gear which drives the auxiliary pumps necessary for diesel generator operation. A root cause investigation pointed to an apparent problem with the lube oil drive gear bearing that caused this gear to improperly mesh with the flexible drive assembly, generating excessive wear. You indicated that the other EDGs onsite had been recently tested successfully. The 1B EDG was inspected for similar wear and this worn condition was not found. We understand that your staff was planning to inspect the 2B EDG once the 2A EDG was returned to service. The other two onsite EDGs are of a different design and thus are unaffected by this problem. A new flexible drive gear was being installed; however, installation of this gear required substantial disassembly of the diesel engine, engine reassembly, and post maintenance testing -- work that could not be completed in the existing Allowed Outage Time (AOT).

Your staff requested this NOED after consideration of the safety significance and potential consequences of such an action. Your staff concluded that remaining at power for an additional six-day period while completing the repairs to the 2A EDG would not result in an undue risk to the health and safety of the public. That conclusion was based on risk insights that qualitatively indicated no net increase in radiological risk as a result of having this EDG out of service for up to six additional days, as well as your confidence that the ongoing repairs to the EDG would be effective and would be completed within this discretionary period. Your staff's conclusion that this NOED was safety and risk neutral was, in part, based on a number of compensatory, risk management measures implemented while the 2A EDG was out-of-service.

As compensatory measures during the period of the NOED, your staff committed to: (1) postpone any elective maintenance on the 2B EDG, (2) suspend any discretionary maintenance or testing on any Unit 2 safety-related equipment or the offsite power system, (3) ensure that all four offsite power circuits were available, even though only two were required to be operable by TSs, (4) shut down Unit 2 if threatened by severe weather with the potential to interrupt offsite power during the time the NOED was in effect, (5) train and station a dedicated operator to utilize the non-safety-related 5,400 kW 0C EDG to power either Unit 2 vital bus in the event of a loss of offsite power, as well as to cross-connect key motor control centers to provide power to necessary equipment, and (6) assign an operator to control the auxiliary feedwater flow control valves in the event that flow control was lost following a loss of offsite power.

The NRC's basis for this discretion considered: (1) the availability and recent satisfactory testing of the four other EDGs onsite; (2) the availability of all offsite electrical sources; (3) the absence of adverse weather or generation shortages that would impact the reliability of these power supplies; (4) the comprehensive list of compensatory actions undertaken to ensure that the extended LCO did not result in a net increase in radiological risk; (5) indications that your repairs to the 2A EDG would be successfully implemented during the discretionary period, and (6) the fact that the apparent root cause had been identified and that no failure mechanisms common to the EDGs were identified.

Based on the above considerations, the staff concluded that Criterion B.2.1.1.a and the applicable criteria in Section C.4 to NRC Manual Chapter 9900, "Technical Guidance, Operation - Notices of Enforcement Discretion" were met. Criterion B.2.1.1.a states that for an operating plant, the NOED is intended to avoid unnecessary transients as a result of compliance with the license condition and, thus, minimize potential safety consequences and operational risks.

On the basis of the staff's evaluation of your request, we concluded that issuance of this NOED is consistent with the Enforcement Policy and staff guidance, and has no adverse impact on public health and safety. Therefore, it is our intention to exercise discretion not to enforce compliance with TS 3.8.1 for the six day period starting at 3:00 a.m., on January 27, 2002, and ending at 3:00 a.m., on February 2, 2002.

As stated in the Enforcement Policy, action will be taken, to the extent that violations were involved, for the root causes that led to the noncompliance for which this NOED was requested.

Sincerely,
/RA/
A. Randolph Blough, Director
Division of Reactor Projects

Enclosure: NOED Request from Calvert Cliffs Nuclear Power Plant, Inc. dated January 29, 2002

Docket No. 50-318
License No. DPR-69
NOED No. 2002-01-01

cc w/encl:
M. Geckle, Director, Nuclear Regulatory Matters (CCNPPI)
R. McLean, Administrator, Nuclear Evaluations
J. Walter, Engineering Division, Public Service Commission of Maryland
K. Burger, Esquire, Maryland People's Counsel
R. Ochs, Maryland Safe Energy Coalition
J. Petro, Constellation Power Source
State of Maryland (2)

 

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