Nebraska Public Power District
ATTN: Guy R. Horn, Vice President - Nuclear
1414 15th Street
Columbus, Nebraska 68601
SUBJECT: NOTICE OF VIOLATION AND PROPOSED IMPOSITION OF CIVIL PENALTY -$50,000 (NRC Inspection Report Nos. 50-298/96-04 and 50-298/96-08)
Dear Mr. Horn:
This refers to the predecisional enforcement conference held in the NRC's Arlington, Texas office on April 1, 1996, with you and other representatives from the Nebraska Public Power District (NPPD). The conference was conducted to discuss apparent violations of requirements identified during NRC inspections conducted on February 5 through 22, and on February 26 through March 1, 1996, at the Cooper Nuclear Station (Cooper). The NRC inspection reports, which were the subject of the conference, described three apparent violations related to: (1) the improper modification of the main steam tunnel blowout panel sections; (2) the improper modification of the solenoid valves which control the muffler bypass valves associated with each emergency diesel generator; and (3) the inadequate isolation of the control power circuitry for Diesel Generator 2 from the potential effects of a postulated control room fire.
Based on the information developed during the inspection and the information that you provided during the conference, the NRC has determined that violations of NRC requirements occurred. These violations are cited in the enclosed Notice of Violation and Proposed Imposition of Civil Penalty (Notice) and the circumstances surrounding them are described in detail in the subject inspection reports.
The first violation identified in the attached Notice, and the only violation that was assessed a civil penalty, involves a modification to the main steam tunnel blowout panels. These panels operate to relieve pressure in the steam tunnel in the event of a main steam line break and ensure that external forces on primary containment would not cause primary containment to fail. The panels were modified in June 1985 when fiberglass was applied to prevent secondary containment leakage. However, no evaluation had been performed, as required by 10 CFR 50.59, to determine whether this modification constituted an unreviewed safety question.
Subsequent to this issue being identified in November 1995, Cooper's analysis indicated that the fiberglass changed the characteristics of the panels such that a pressure greater than 15 psi would have occurred in the steam tunnel during a postulated main steam line break, which would have exceeded design and licensed safety analysis limits. However, as a result of its recent extensive analysis, Cooper management now believes that the external forces on primary containment would not have caused containment failure. Although Cooper's analysis indicated that the potential consequences of the conditions were minimal, the significance of this violation is based on the fact that NPPD operated Cooper in an unanalyzed condition from approximately July 1985 until November 1995. Therefore, this violation has been categorized in accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions" (Enforcement Policy), NUREG-1600, at Severity Level III.
In accordance with the Enforcement Policy, a base civil penalty in the amount of $50,000 is considered for a Severity Level III violation. Because your facility has been the subject of escalated enforcement actions within the last 2 years, the NRC considered whether credit was warranted for Identification and Corrective Action in accordance with the civil penalty assessment process in Section VI.B.2 of the Enforcement Policy. In evaluating the Identification factor, NRC considered your position at the conference that Cooper had no opportunities to identify the violation. However, in view of the fact that NPPD had modified the panels in the first place and, therefore, should have known of the change, and that an NRC inspector's questioning led to the subsequent identification of the problem, NRC has determined that no credit is warranted for Identification. NRC's evaluation of the information provided at the conference concluded that credit was warranted for the Corrective Action factor. Cooper's corrective actions included removing the fiberglass and restoring the design function of the panels, improving the description of the panels in the updated safety analysis report (USAR), inspecting other blowout panels, beginning a review of a random sample of past maintenance work for unreviewed safety questions and unauthorized modifications, and beginning the development of a high energy line break design criteria document.
Therefore, to emphasize the importance of ensuring that the plant is operated within the confines of the USAR, I have been authorized, after consultation with the Director, Office of Enforcement, to issue the enclosed Notice of Violation and Proposed Imposition of Civil Penalty in the base amount of $50,000.
The second violation identified in the attached Notice, but not assessed a civil penalty, involves Cooper's failure to electrically isolate Diesel Generator 2 control circuitry from the effects of a fire-induced cable fault created by a (postulated) fire in the control room or cable spreading room, in violation of 10 CFR 50, Appendix R, Section III.G. This diesel generator is identified in Cooper's Safe and Alternate Shutdown Analysis Report as the alternate safe-shutdown equipment. As a result of this violation, an electrical fault caused by a postulated control room fire could have prevented the diesel generator from performing its intended function of achieving and maintaining hot shutdown.
During the predecisional enforcement conference, you informed us that the circumstances surrounding the apparent violation of 10 CFR 50, Appendix R, were different from the circumstances reported in Licensee Event Report (LER) 95-20 and from those documented in NRC Inspection Report 50-298/96-08. In July 1994, an engineering review identified this condition (reference LER 94-16), and in August 1994, Cooper modified the wiring to correct the violation. In preparation for the enforcement conference, your staff identified that these corrective actions were effective in correcting the original design deficiency. However, the Appendix R violation recurred in January 1995 as a result of a wiring modification performed in accordance with Design Change 94-302, Revision 0. As a result of this design change, the diesel generator control relays (listed in LER 95-20) were once again vulnerable to a fire in the control room. Accordingly, the potential violation identified in LER 95-20 and NRC Inspection Report 96-08 existed, although caused by a different design modification than specified in the inspection report.
After investigating the circumstances of this violation, Cooper determined that the root cause was attributed to an inadequacy in the design change process. Specifically, Cooper found that the design change process allowed the use of drawings which did not have all pending changes identified.
As a result of the identified Appendix R violation, a condition existed from approximately January 3, 1995 until November 25, 1995, in which a fire-induced electrical fault on the wiring for the indicating lights for Diesel Generator 2 (on Board "C") could have caused Diesel Generator 2 to stop, if running, and would have prevented the diesel generator from starting when required. Therefore, this violation has been categorized in accordance with the Enforcement Policy at Severity Level III.
As discussed above, a base civil penalty in the amount of $50,000 is considered for a Severity Level III violation. Because your facility has been the subject of escalated enforcement actions within the last 2 years, the NRC considered whether credit was warranted for Identification and Corrective Action in accordance with the civil penalty assessment process in Section VI.B.2 of the Enforcement Policy. In evaluating the Identification factor, NRC noted that, in both instances (1994 and 1995), Cooper engineers identified the condition before an event occurred and before being identified by the NRC. Therefore, NRC has determined that credit for the Identification factor was warranted. NRC's evaluation of the information provided at the conference concluded that credit was warranted for the Corrective Action factor. Cooper's corrective actions included isolating the control circuitry, investigating and correcting the existing drawing control program process, evaluating which disciplines were affected by the root cause, evaluating a sample of panel drawings to identify adverse modification interrelationships, training on the changed process, and having Cooper's Quality Assurance organization perform an independent evaluation of drawing control program.
In the civil penalty assessment process, NRC also considered the fact that, except for a 4-month period in 1994, this Appendix R violation has existed at Cooper since 1987. We balanced our concern over this issue with the intent of the enforcement policy to encourage licensees to identify problems before an event occurs and to take corrective actions. Therefore, in accordance with the intent of the enforcement policy, I have been authorized, after consultation with the Director, Office of Enforcement, not to propose a civil penalty for this violation. Significant violations of this nature in the future could, however, result in a civil penalty.
The third and final apparent violation identified in the subject inspection reports involved the improper modification of the solenoid valves which control the muffler bypass valves associated with each emergency diesel generator. This modification was intended to preclude foreign material exclusion entry into the solenoid exhaust. However, it also raised the solenoid exhaust backpressure, which intermittently prevented actuation of the solenoid pilot valve on Diesel Generator 2. Therefore, the Diesel Generator 2 muffler bypass system was inoperable, under certain conditions, for approximately 20 days. (Note: Although the same vulnerability existed on Diesel Generator 1, repeated testing of its muffler bypass system demonstrated that its operability was not affected.)
Based on the information provided during the conference, NRC concluded that although this modification affected operability of Diesel Generator 2 under certain conditions when the muffler bypass line was required, Diesel Generator 1 would have been operable for all design basis events. Therefore, this violation has been categorized in accordance with the Enforcement Policy, NUREG-1600, at Severity Level IV, and is cited in the attached Notice.
In reviewing these three issues, Cooper management expressed their concern, and NRC agreed, that these issues involved significant and broad engineering issues. Cooper management briefly highlighted initiatives to sensitize its workers and engineers to the above specific issues, and to ensure that no other modifications are made to the plant without the required analyses. For example, Cooper management noted that engineers are reviewing all work requests to ensure that they include no inadvertent modifications. Also, a work planning group is overseeing work requests to also ensure that the appropriate authorizations are obtained prior to work. In the meantime, Cooper management is evaluating other steps to improve its processes. Improvements to Cooper's design control processes will be the topic of future management meetings between NRC and Cooper management.
You are required to respond to this letter and should follow the instructions specified in the enclosed Notice when preparing your response. In your response, you should document the specific actions taken and any additional actions you plan to prevent recurrence. After reviewing your response to this Notice, including your proposed corrective actions and the results of future inspections, the NRC will determine whether further NRC enforcement action is necessary to ensure compliance with NRC 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). To the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be placed in the PDR without redaction.
Sincerely, original signed by L. J. Callan Regional Administrator
Notice of Violation and
Proposed Imposition of Civil Penalty
Nebraska Public Power District
ATTN: John R. McPhail, General Counsel
P.O. Box 499
Columbus, Nebraska 68602-0499
Nebraska Public Power District
ATTN: John Mueller, Site Manager
P.O. Box 98
Brownville, Nebraska 68321
Nebraska Public Power District
ATTN: Robert C. Godley, Nuclear
Licensing & Safety Manager
P.O. Box 98
Brownville, Nebraska 68321
ATTN: R. J. Singer, Manager-Nuclear
907 Walnut Street
P.O. Box 657
Des Moines, Iowa 50303
Lincoln Electric System
ATTN: Mr. Ron Stoddard
11th and O Streets
Lincoln, Nebraska 68508
Nebraska Department of Environmental
ATTN: Randolph Wood, Director
P.O. Box 98922
Lincoln, Nebraska 68509-8922
Nemaha County Board of Commissioners
Nemaha County Courthouse
1824 N Street
Auburn, Nebraska 68305
Nebraska Department of Health
ATTN: Cheryl Rogers, LLRW Program Manager
Environmental Protection Section
301 Centennial Mall, South
P.O. Box 95007
Lincoln, Nebraska 68509-5007
Nebraska Department of Health
ATTN: Dr. Mark B. Horton, M.S.P.H. Director
P.O. Box 950070
Lincoln, Nebraska 68509-5007
Department of Natural Resources
ATTN: R. A. Kucera, Department Director
of Intergovernmental Cooperation
P.O. Box 176
Jefferson City, Missouri 65102
Kansas Radiation Control Program Director
Nebraska Public Power District Docket No. 50-298 Cooper Nuclear Station License No. DRP-46 Eas 96-062, 96-094
During NRC inspections conducted from February 5 through February 22, 1996, and from February 26 through March 1, 1996, violations of NRC requirements were identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," NUREG-1600, the Nuclear Regulatory Commission proposes to impose a civil penalty pursuant to Section 234 of the Atomic Energy Act of 1954, as amended (Act), 42 U.S.C. 2282, and 10 CFR 2.205. The particular violations and associated civil penalty are set forth below:
I. Violation Assessed a Civil Penalty
10 CFR 50.59(a)(1) states, in part, that a licensee may make changes in the facility as described in the safety analysis report without prior Commission approval unless the change involves a change in the technical specifications incorporated in the license or an unreviewed safety question. 10 CFR 50.59(b)(1) states in part that the licensee shall maintain records of changes in the facility, to the extent that these changes constitute changes in the facility as described in the safety analysis report, and that these records must include a written safety evaluation which provides the basis for the determination that the change did not involve an unreviewed safety question.
The Updated Safety Analysis Report (USAR) for Cooper Nuclear Station, Section 12.1, and the June 8, 1973, supplement to USAR Amendment 25 state that the steam tunnel blowout panel sections will operate to relieve pressure in the steam tunnel in the event of a main steam line break. The associated safety analysis described in the supplement to Amendment 25 indicates that the steam tunnel door and blowout panels operate to ensure steam tunnel pressure remains below the design and licensed safety analysis limit of 15 psi.
Contrary to the above, between July 1985 and November 1995, the facility was not operated as described in the USAR and a written safety evaluation of the change from the USAR had not been performed to determine whether this change involved an unreviewed safety question. Specifically, the licensee made a change to the facility when fiberglass was applied to the steam tunnel blowout panels in July 1985. In November 1995, the licensee determined that the change had significantly altered the material characteristics of the blowout panels such that, in the event of a steam line break inside the steam tunnel, the peak steam tunnel pressure would have been greater than the analyzed limit of 15 psi, and therefore that the change had resulted in an unreviewed safety question. (01013)
This is a Severity Level III violation (Supplement I).
Civil Penalty - $50,000.
II. Violations Not Assessed a Civil Penalty
A. Title 10 of CFR 50, Appendix R, Section III.G.1., requires that fire protection features be provided for structures, systems, and components important to safe shutdown. These features shall be capable of limiting fire damage so that one train of systems necessary to achieve and maintain hot shutdown conditions from either the control room or emergency control station is free of fire damage.
Contrary to the above, from approximately January 3 to November 25, 1995, fire protection features capable of limiting fire damage so that one train of the systems necessary to achieve and maintain hot shutdown conditions from either the control room or emergency control station would be free of fire damage, were not provided. Specifically, control power circuitry for Diesel Generator 2 (the protected safe shutdown train power supply) was not protected from the effects of a postulated control room fire. A fire in the control room could have rendered the diesel generator unable to perform its safe shutdown function and hot shutdown conditions could not have been maintained. (02013)This is a Severity Level III violation (Supplement I).
B. 10 CFR Part 50, Appendix B, Criterion III, requires, in part, that measures shall be established to assure that applicable regulatory requirements and the design basis as defined in 10 CFR 50.2 are correctly translated into specifications, drawings, procedures, and instructions. In addition, design changes shall be subject to design control measures commensurate with those applied to the original design.
The diesel generator system is required by the Updated Safety Analysis Report (USAR), Section VIII-5.1, to provide alternating current power to shut down the reactor following abnormal operational transients and postulated accidents. USAR Sections I-5.1.5 and 5.1.6 require that the design of the system must include allowances for environmental phenomena, such as tornados and seismic events. The diesel generator muffler bypass subsystem design provides the analyzed exhaust path under seismic and tornado conditions, since the muffler and associated piping are not analyzed for these conditions.
Contrary to the above, as discussed in NRC Inspection Report 50-298/96-04, during the November 1995 refueling outage, design control measures were inadequate in that an unauthorized modification was made to the Diesel Generators 1 and 2 muffler bypass systems, resulting in the muffler bypass system for Diesel Generator 2 being inoperable from December 27, 1995 to January 15, 1996. (03014)This is a Severity Level IV violation (Supplement I).
Pursuant to the provisions of 10 CFR 2.201, the Nebraska Public Power District (Licensee) is hereby required to submit a written statement or explanation to the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, within 30 days of the date of this Notice of Violation and Proposed Imposition of Civil Penalty (Notice). This reply should be clearly marked as a "Reply to a Notice of Violation" and should include for each alleged violation: (1) admission or denial of the alleged violation, (2) the reasons for the violation if admitted, and if denied, the reasons why, (3) the corrective steps that have been taken and the results achieved, (4) the corrective steps that will be taken to avoid further violations, and (5) the date when full compliance will be achieved. If an adequate reply is not received within the time specified in this Notice, an order or a Demand for Information may be issued as why the license should not be modified, suspended, or revoked or why such other action as may be proper should not be taken. Consideration may be given to extending the response time for good cause shown. Under the authority of Section 182 of the Act, 42 U.S.C. 2232, this response shall be submitted under oath or affirmation.
Within the same time as provided for the response required above under 10 CFR 2.201, the Licensee may pay the civil penalty by letter addressed to the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, with a check, draft, money order, or electronic transfer payable to the Treasurer of the United States in the amount of the civil penalty proposed above, or may protest imposition of the civil penalty in whole or in part, by a written answer addressed to the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission. Should the Licensee fail to answer within the time specified, an order imposing the civil penalty will be issued. Should the Licensee elect to file an answer in accordance with 10 CFR 2.205 protesting the civil penalty, in whole or in part, such answer should be clearly marked as an "Answer to a Notice of Violation" and may: (1) deny the violations listed in this Notice, in whole or in part, (2) demonstrate extenuating circumstances, (3) show error in this Notice, or (4) show other reasons why the penalty should not be imposed. In addition to protesting the civil penalty in whole or in part, such answer may request remission or mitigation of the penalty.
In requesting mitigation of the proposed penalty, the factors addressed in Section VI.B.2 of the Enforcement Policy should be addressed. Any written answer in accordance with 10 CFR 2.205 should be set forth separately from the statement or explanation in reply pursuant to 10 CFR 2.201, but may incorporate parts of the 10 CFR 2.201 reply by specific reference (e.g., citing page and paragraph numbers) to avoid repetition. The attention of the Licensee is directed to the other provisions of 10 CFR 2.205, regarding the procedure for imposing a civil penalty.
Upon failure to pay any civil penalty due which subsequently has been determined in accordance with the applicable provisions of 10 CFR 2.205, this matter may be referred to the Attorney General, and the penalty, unless compromised, remitted, or mitigated, may be collected by civil action pursuant to Section 234c of the Act, 42 U.S.C. 2282c.
The response noted above (Reply to Notice of Violation, letter with payment of civil penalty, and Answer to a Notice of Violation) should be addressed to: James Lieberman, Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, One White Flint North, 11555 Rockville Pike, Rockville, MD 20852-2738, with a copy to the Regional Administrator, ATTN: Enforcement Officer, U.S. Nuclear Regulatory Commission, Region IV.
Because your response will be placed in the NRC Public Document Room (PDR), to the extent possible, it should not include any personal privacy, proprietary, or safeguards information so that it can be placed in the PDR without redaction. However, if you find it necessary to include such information, you should clearly indicate the specific information that you desire not to be placed in the PDR, and provide the legal basis to support your request for withholding the information from the public.
Dated at Arlington, Texas,
this 17th day of April 1996