IR 05000413/1996019

Insp Repts 50-413/96-19 & 50-414/96-19 on 961007, 961127, & 970206.Violation Noted.Major Areas inspected:in-office Review of Licensee Describing Changes to CNS UFSAR Re Lack of Circuit Breaker Coordination for 600-Vac

ML20136B600
Person / Time
Site:	Catawba
Issue date:	02/21/1997
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20136B580	List: IR 05000413/1996016 IR 05000413/1996019
References
50-413-96-19, 50-414-96-19, NUDOCS 9703110055
Download: ML20136B600 (4)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION II

Docket Nos:

50-413. 50-414 License Nos:

NPF-35, NPF-52 Report Nos.

50-413/96-19. 50-414/96-19 Licensee:

Duke Power Company Facility:

Catawba Nuclear Station, Units 1 and 2 Location:

422 South Church Street Charlotte, NC 28242 Dates:

October 7, 1996 November 27, 1996 and February 6, 1997 Inspector:

Randy Moore Approved by:

Harold Christensen, Chief Engineering Branch Division of Reactor Safety Enclosure 9703110055 970221 PDR ADOCK 05000413 G

PDR

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EXECUTIVE SUMMARY

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Catawba Nuclear Station. Units 1 & 2 NRC Inspection Report 50-413/96-19. 50-414/96-19 This inspection included an in-office review of the licensee's letter dated December 29, 1994 describing changes to the Catawba Nuclear Station, Units 1 and 2. U) dated Final Safety Analysis Report (UFSAR) with regard to the lack of circuit ]reaker coordination for the 600-Vac essential Motor Control Centers (MCCs) and the 125-Vdc system and the NRC's Office of Nuclear Reactor Regulation's review of the UFSAR changes.

One apparent violation was identified.

Specifically, an unreviewed safety cuestion related to the circuit breaker protection for the 600-VAC essential FCCs and the 125-VDC system was disclosed, but the licensee failed to identify the USQ and failed to seek a license amendment in accordance with 10 CFR 50.59(c).

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Reoort Details III. Enaineerina E8 Miscellaneous Engineering Issues (92902)

E8.1 (Closed) Deviation 50-413.414/92-01-06: Failure to Meet FSAR Commitment to IEEE 308-1974 Related to Electrical Breaker Protection The Electrical Distribution System Functional Inspection identified breaker coordination deficiencies in the 600 Vac Motor Control Centers (MCC) and the 125 Vdc Instrumentation & Control System. These deficiencies were inconsistent with the Final Safety Analysis Report statement that the electrical systems conformed to the requirements of IEEE 308-1974.

The licensee evaluated the condition and concluded that the lack of coordination in these referenced systems provided no significant safety concern and was acceptable.

The licensee concluded that the Updated Final Safety Analysis Report (UFSAR) should be revised to resolve the inconsistent statement.

The licensee submitted a December 29. 1994, change to the UFSAR.

During the 1994 evaluation to support the UFSAR change. an Unreviewed Safety Question (US0) was disclosed. The evaluation found that the lack of circuit breaker coordination for the 600-Vac essential MCCs and the 125-Vdc system increased the probability of a malfunction of equipment important to safety.

10 CFR 50.59(a)(2)(1) defines an incre6se in the probability of occurrence of a malfunction of equipment important to safety as a US0.

In lieu of replacing circuit breakers with devices that were in full coordination as stated in the UFSAR. the licensee revised the UFSAR to reflect the as-built non-coordinated condition of the breaker installations.

On September 17, 1996, the NRC informed the licensee by letter that the 50.59 evaluation conclusion was incorrect in that a US0 did exist.

The NRC has determined that the 1994 evaluation was a de facto 50.59 evaluation from the perspective that the electrical systems in question were being changed from a design commitment status of coordinated to the revised design state of " selected coordination." Although the 50.59 evaluation determined that the increase in equipment failure probability was small based on PRA analysis: 10 CFR 50.59(a)(2)(i) defines any increase in 3robability, regardless of magnitude. as a US0.

Based on the above, t1e original construction design change, which did not incorporate the breaker coordination specified in the UFSAR. was a US0.

In fact. a US0 had existed at Catawba for the entire time period between plant start-up and acceptance of the application for amendments to the UFSAR pursuant to 10 CFR 50.90 on September 21, 1996.

10 CFR 50.59(c) states, in part, that the holder of a license authorizing operation of a utilization facility who desires to make a change in the facility or the procedures as described in the safety analysis report, which involve a U50. shall submit an application for amendment of the license pursuant to 10 CFR 50.9.. --. _. -..

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A USO related to circuit breaker coordination for the 600-Vac essential MCCs and the 125-Vdc system existed in that the equipment failure probability increased, but the licensee failed to identify the issue as a US0 and failed to seek a license amendment.

As described in the cover letter to this report, the NRC has decided to

exercise discretion and refrain from issuing a Notice of. Violation. in this' matter. This issue is identified as EEI 50-413, 414/96-19-01.

~ Failure to Perform Adequate 50.59 Evaluation for Safety Related Breaker Coordination Design, for tracking purposes and is considered closed.

The licensee submitted an. operating licensing amendment to the FSAR'on September 21, 1996.

The NRC accepted the amendment on September 28, 1996.

The amendment clarified the statement regarding conformance to IEEE 308-1974 noting the exceptions on the 600 Vac MCCs and the 125 Vdc Instrumentation & Control systems.

Deviation 50-413.414/92-01-06 is closed based on a revision to the FSAR to resolve the inconsistency related to breaker coordination.

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Manaaement Meetinas X1 Exit Meeting Summary The inspector presented the inspection results to licensee management on November 27, 1996, via telephone with Mr. B. McCollum, Catawba Site Vice President. The following dissenting opinion was provided by management:

Catawba management disagrees that there was a~USQ when the 50.59 was-written'in December 1994. Catawba management further stated that the NRC's determination that a US0 existed was made following the NRC's recent re-interpretation of the applicable FSAR commitment regarding breaker coordination.

Acronyms and Abbreviations IEEE Institute of Electrical and Electronic Engineers MCC Motor Control Centers PRA Probabilistic Risk Assessment VAC

. Volts alternating-current VDC Volts direct-current UFSAR Updated Final Safety Analysis Report US0 Unreviewed Safety Question j