IR 05000293/1997005

Discusses Insp Repts 50-293/97-05,50-293/97-12 & 50-293/97-13 & Forwards Notice of Violation & Proposed Imposition of Civil Penalty in Amount of $165,000

ML20217N535
Person / Time
Site:	Pilgrim
Issue date:	04/27/1998
From:	Miller H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	Olivier L BOSTON EDISON CO.
Shared Package
ML20217N541	List: IR 05000293/1997005 ML20217N597
References
50-293-97-05, 50-293-97-12, 50-293-97-13, 50-293-97-5, EA-97-482, EA-97-525, EA-98-052, EA-98-52, NUDOCS 9805050361
Download: ML20217N535 (7)

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% * * * * * ,8 April 27,1998 EAs97-482; 97-525;98-052 Mr. Leon Vice President - Nuclear Boston Edison Company Pilgrim Nuclear Power Station 600 Rocky Hill Road Plymouth, Massachusetts 02360-5599 SUBJECT: NOTICE OF VIOLATION AND PROPOSED IMPOSITION OF CIVIL PENALTY

- $165,000; AND EXERCISE OF ENFORCEMENT DISCRETION (NRC Inspection Report Nos. 50-293/97-05,97-12 and 97-13)

Dear Mr. Olivier:

This letter refers to the three subject NRC inspections conducted between May 14,1997,and January 6,1998, at the Pilgrim Nuclear Power Station in Plymouth, Massachusetts, the findings of which were discussed with Mr. H. V. Oheim and members of your staff during several exit meetings, the last of which was held on January 30,1998. The first of these inspections examined the corrective actions associated with the findings from a January 1995 self-assessment of the Pilgrim safety-related cooling water systems and other related issues.

The second inspection reviewed various engineering activities, including the replacement and subsequent modification of two 480/120 volt safeguard control transformers. The third inspection was a routine integrated inspection which, in part, reviewed an issue related to the reliability of the salt service water (SSW) pump operation. The inspection reports were sent to you previously on October 21,1997, December 17,1997, and February 6,1998.

On November 21,1997, a predecisional enforcement conference (conference) was conducted with you and members of your staff, to discuss the violations related to the first two inspections, their causes, and your corrective actions. The apparent violations identified in NRC inspection Report 97-12, issued on December 17,1997, related to the 480/120 voit transformers, were discussed at the conference, even though the inspection report had not been issued at the time of that conference. On December 16,1997, Mr. Oheim of your staff informed Mr. Wiggins of my staff that another conference was not needed to further discuss those issues.

Based on the findings of the inspections and information provided during the conference, two Seventy Level lil violations and one Severity Level lli problem (consisting of multiple violations) ,

are being cited and are described in the enclosed Notice of Violation and Proposed Imposition 1 of Civil Penalty (Notice). These violations involved a number of failures to either promptly I identify conditions adverse to quality and/or failures to promptly and effectively correct the conditions once they were identified, contrary to 10 CFR Part 50, Appendix B, Criterion XVI, as well as violations of design control requirements, and 10 CFR 50.59.

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Boston Edison Company 2 The first Severity Level lli violation involved an unreviewed safety question (USO) resulting from a modification involving insulation on recirculation loop piping located in the drywell performed in 1984. The design change involved a USQ in that the probability of a malfunction of the emergency core cooling system (ECCS) pumps (i.e., residual heat removal (RHR) and core spray) was increased due to the potentially higher line pressure losses caused by the collection of insulation debris on the pump suction strainers. To alleviate this, the design change took credit for post-accident containment overpressure to assure adequate ECCS pump net positive suction head (NPSH). Crediting of containment overpressure was inconsistent ,

with the plant licensing basis as described in the Updated Final Safety Analysis Report ]

(UFSAR). However, you failed to recognize that crediting containment overpressure increased the probability of a malfunction of the ECCS pumps, and the safety evaluation performed to support the modification incorrectly concluded that the change did not involve a USO.

Consequently, the change was made without NRC approval. In addition, this issue was not appropriately addressed until January 20,1997 (when you requested NRC review and approval for including containment pressure as a component of NPSH margin in the Pilgrim i

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licensing basis) even though there were prior opportunities to identify and correct the problem, namely: (1) the 1995 service water system operational performance inspection (SWSOPI) self-assessment that identified that the 1984 safety evaluation may have improperly credited containment overpressure in the NPSH calculations; (2) a subsequent safety evaluation completed on March 25,1996 which also incorrectly concluded that the 1984 plant modification did not involve a USO; and (3) the report of an independent review of the containment overpressure issue performed by Yankee Atomic Electric Company in 1996 that concluded that containment overpressure was not credited in the Pilgrim licensing basis.

The second Severity Level 111 violation involves a design deficiency which introduced an unintended trip function in the microprocessors that control the transformers which supply 120 Vac power to safety-related instrument busses. Following an event on April 1,1997 in which the unintended trip function caused a common mode malfunction of two transformers, the safety evaluation performed to support replacement of the microprocessors failed to ,

recognize the existence of a USO. ]

The Severity Level lli problem consisting of seven violations involved cond;tions adverse to quality that were not identified and/or corrected including: (1) operation of the plant with salt service water (SSW) system inlet temperatures higher than designed; (2) a single failure vulnerability in the SSW system design; (3) failure to translate, into procedures, the design requirement to isolate non-essential reactor building closed cooling water (RBCCW) system ;

loads during accident conditions; (4) failure to adequately translate, into procedures, residual l heat removal (RHR) system design flow rates for containment heat removal; (5) deficiencies )

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in emergency diesel generator (EDG) loading calculations and procedures; (6) operation of the EDGs at ambient temperatures higher than the design limit; and (7) inaccuracies in the !

environmental qualification (EO) drywell temperature profile for electric equipment important l to safety.

Several of these adverse conditions resulted from failure to properly translate the design bases of the plant into specifications, procedures, and instr"ctions. For example, the RHR system design flow rate of 5100 gpm used in design basis containment heat transfer and pressure / temperature calculations was not properly translated into procedures in that the flow

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Boston Edison Company 3 rates specified in the system operating procedure were not supported by calculations that considered the effects of instrument accuracy. Specifically, the RHR operating procedure specified a flow range of 4800 to 5100 gpm for containment cooling during accident conditions. There was no analysis to confirm that adequate heat removal would be provided at the lower flow rate specified in the operating procedure, including the effects of instrument error. Similarly, there was no analysis to demonstrate that flows greater than 5100 gpm (which, after considering the effects of instrument error, could occur) would not exceed the design limitations of the RHR heat exchangers.

In some cases, you identified the design deficiency, but failed to take prompt action to correct the deficiency once it was identified. For example, during the service water system operational performance inspection (SWSOPI) self-assessment in 1995, you identified that no procedural guidance existed to isolate the non-essential RBCCW system heat loads during an accident, an action assumed in the licensing bases for the plant. However, at the time of the NRC inspection in 1997, no action had been taken to address the identified deficiency. The NRC is concerned that, although you identified inconsistencies between the safety analyses and plant specifications and procedures, you apparently failed to recognize the significance of the conditions in that prompt action was not taken to correct the discrepancies. You also failed to recognize that some of these conditions resulted in the plant being operated outside of the design basis as evidenced by the fact that the conditions were not reported to the NRC pursuant to 10 CFR 50.72 and 50.73.

Additionally, in some cases, your corrective actions to address the deficiencies after they were identified, were inadequate because you either failed to perform required safety evaluations, or performed safety evaluations that failed to identify unreviewed safety questions (USQs).

In a number of cases, you limited your formal evaluations to operability determinations and often relied upon engineering judgement rather than formal analyses to support your actions.

For example, although you identified as early as July 1994, that a design basis change was needed to support operation of the plant with SSW inlet temperatures above the design limit of 65'F specified in Updated Final Safety Analysis Report (UFSAR), a safety evaluation to support a change to the licensmg basis was not performed until March 1996 even though you operated the plant during the interim with SSW temperatures in excess of 65'F. In the interim, you relied on an operability determination that concluded that the RBCCW system was operable with elevated SSW temperatures, and you used engineering judgement to support the use of " rolling averages" to justify operation of the plant with SSW temperatures above 65'F. When a formal safaty evaluation was performed, the evaluation was inadequate because post-accident containment overpressure was inappropriately credited in ECCS pump NPSH margin calculations contrary to the plant's licensing basis.

The NRC is concerned that the plant was operated outside of the NRC approved licensing bases because of an apparent fundamental misunderstanding of what constitutes a change to the design and licensing bases. While there were no resultant adverse safety consequences in any of these cases, the potential existed that, had a design basis accident occurred, safety-related equipment and systems were not assured of accomplishing their design functions.

Additionally, the failure to identify and/or correct these conditions adverse to quality is of significant regulatory concern because the NRC relies upon licensees to operate the plant within the approved licensing basis and to correctly assess changes to the plant or its operations to assure that unreviewed safety questions do not exist.

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Boston Edison Company 4 The violations represent a failure to take corrective actions to resolve programmatic weaknesses in your design control and safety evaluation processes. The violations associated

' with inappropriately crediting containment overpressure in calculations of ECCS pump NPSH margin, and a design deficiency in the microprocessors that control the transformers which supply 120 Vac power to safety-related instrument busses, are each categorized as separate Severity Level !ll violations in accordance with the " General Statement of Policy and Procedure for NRC Enforcement Actions" (Enforcement Policy), NUREG 1600,in that each involved the creation of a USQ. The remainder of the violations are classified in the aggregate as a Severity Level 111 problem because they represent a failure to implement corrective actions in a number of different areas.

in accordance with the Enforcement Policy, a base civil penalty in the amount of $55,000is

, considered for each Severity Level 111 violation or problem. Since Pilgrim has been the subject of escalated enforcement actions within the last two years,' the NRC considered whether credit was warranted for /dentification and Corrective Action in accordance with the civil penalty assessment process in Section VI.B.2 of the Enforcement Policy for each, Severity Level 111 violation and the Severity Level 111 problem. While you identified some of the technical issues, no credit is warranted for identification because the NRC identified the USQs and your failure to promptly identify and resolve these conditions adverse to quality. Your corrective actions, once you were put on notice by the NRC, included: 1) procedure revisions; 2)

performance of the necessary safety evaluations; 3) broad scope UFSAR and licensing basis documentation reviews; 4) revision of the guidance for evaluating conditions for reportability; and 5) increased management attention to the corrective action process. Since these corrective actions appear comprehensive, credit is warranted for corrective actions.

Therefore, to emphasize the importance of timely identification and comprehensive correction of problems and in recognition of your previous escalated enforcement actions, I have been authonzed, after consultation with the Director, Office of Enforcement, to issue the enclosed Notice of Violation and Proposed imposition of Civil Penalty in the amount of $165,000. This is comprised of a base civil penalty of $55,000 for each Severity Level ill violation and for the Seventy Level til problem in Section I of the Notice. j l

Four separate Severity Level IV violations for failure to make timely notifications and reports  ;

to the NRC in accordance with 10 CFR 50.72 and 10 CFR 50.73 for some of the situations described in Section I of the Notice are described in Section 11.

Additionally, during your follow-up review of EDG loading, conducted as a result of the violations identified during the NRC SWSOPl follow-up inspection, you identified a design deficiency associated with the thermal cverload relay trip settings for the SSW pumps that j could have resulted in an inadvertent trip of the pumps and a loss of all SSW cooling. This I issue was identified as an apparent violation of 10 CFR Part 50, Appendix B, Criterion ill in NRC Inspection Report 97-13. The NRC has determined that the failure to assure that the SSW design bases were correctly translated into the overload trip settings constituted a

e.g., A Notice of Violation without a civil penalty was issued on October 21,1996 for a Severity level HI problein involving a violation of containmant integrity Technical Specification requirements and failure to correct deficiencies in electrical penetrations (EA 96-271).

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Boston Edison Company 5 violation of NRC requirements which could be considered for escalated enforcement and subject to civil penalties. However, after consultation with the Director, Office of Enforcement, I have been authorized to not issue a Notice of Violation and not propose a civil penalty for this issue in accordance with the provisions provided in Section Vll.B.4 of the Enforcement Policy. This decision was made after consideration that: (1) the violation was identified by your staff as part of corrective action for violations that were subject to escalated enforcement action; (2) the violation has a similar root cause as the other design deficiencies for which escalated action is being issued; (3) it does not substantially change the safety significance or the character of the regulatory concern arising from the initial violations; (4)

immediate corrective action was taken to reset the trip setpoints; and (5) you have planned long term corrective actions to address the root cause of the violation. The exercise of discretion acknowledges your effort to perform comprehensive actions to identify and correct similar violations to those for which escalated enforcement action was issued.

You are required to respond to this letter and should follow the instructions specified in the enclosed Notice when preparing your response. Due to the programmatic nature of these violations, the NRC expects that your response will address not only the specific violations cited, but will also include the results of any extent of condition reviews that you have performed in the areas of design control, safety evaluations, and reportability. The NRC will use your response, in part, to determine whether further enforcement action is necessary to ensure compliance with regulatory requirements.

in accordance with 10 CFR 2.790 of the NRC's " Rules of Practice," a copy of this letter, its enclosure, and your response will be placed in the NRC Public Document Room (PDR).

Sincerely, H ert J. Miller Regional Administrator Docket No. 50-293 License No. DPR 35 Enclosure: Notice of Violation and Proposed imposition of Civil Penalty

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Boston Edison Company 6 cc w/enci:

R. Ledgett, Executive Vice President - Operations C. Goddard, Plant Department Manager N. Desmond, Regulatory Relations D. Tarantino, Nuclear Information Manager R. Hallisey, Department of Public Health, Commonwealth of Massachusetts The Honorable Therese Murray The Honorable Joseph Gallitano B. Abbanat, Department of Public Utilities Chairman, Plymouth Board of Selectmen Chairman, Duxbury Board of Selectmen Chairman, Nuclear Matters Committee Plymouth Civil Defense Director P. Gromer, Massachusetts Secretary of Energy Resources J. Miller, Senior issues Manager J. Fleming A. Nogee, MASSPIRG Office of the Commissioner, Massachusetts Department of Environmental Quality Engineering Office of the Attorney General, Commonwealth of Massachusetts T. Rapone, Massachusetts Executive Office of Public Safety Chairman, Citizens Urging Responsible Energy Commonwealth of Massachusetts, SLO Designee I

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Boston Edison Company DISTRIBUTION:

PUBLIC SECY CA LCallan, EDO AThadani, DEDE JLieberman, OE HMiller, RI FDavis, OGC

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SCollins, NRR RZimmerman, NRR Enforcement Coordinators Rl, Ril, Rlli, RIV BBeecher, GPA/PA GCaputo, Ol DBangart, OSP HBell, OlG TMartin, AEOD OE:Chron OE:EA DCS NUDOCS DScrenci, PAO-Ri NSheehan, PAO-RI

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LTremper, OC Nuclear Safety Information Center (NSIC)

NRC Resident inspector - Pilgrim cis0004

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