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EA-95-238 - Three Mile Island 1 (GPU Nuclear Corp.)EA 95-238 Mr. James Knubel
SUBJECT: NOTICE OF VIOLATION
(NRC INSPECTION REPORT NO. 50-289/95-16)
Dear Mr. Knubel: This refers to the inspection conducted on September 25-29, 1995, at the Three Mile Island, Unit 1 Nuclear Station (TMI) facility and from October 10-11, 1995, at the GPU Nuclear (GPUN) Office in Parsippany, New Jersey. The purpose of the inspection was to determine whether activities authorized by the license were conducted safely and in accordance with NRC requirements. The inspectors also reviewed GPUN's activities in response to a crack and subsequent leak identified in an unisolable section of the reactor coolant system (RCS) drain line on September 9, 1995, while in the process of cooling down for the Cycle 11 refueling outage. While reviewing GPUN's response to past problems with drain lines, the inspectors identified apparent violations of NRC requirements, which were described in the NRC inspection report transmitted with our letter, dated November 7, 1995. On December 18, 1995, a Predecisional Enforcement Conference was conducted with Mr. R. W. Keaten, Vice President Technical Functions, and other members of your staff to discuss the violations, their causes, and your corrective actions. Based on the information developed during the inspection and the information provided during the conference, the NRC has determined that violations of NRC requirements occurred. These violations are cited in the enclosed Notice of Violation (Notice) and the circumstances surrounding them are described in detail in the subject inspection report. The first violation involved GPUN's failure to control adequately a modification to the RCS drain line piping. The modification was developed by GPUN as a result of a drain line analysis performed in 1990. The analysis of the "B" line indicated thermal expansion stresses approximately 4% above the allowables specified in the design code of record (USAS B31.1-1967). GPUN determined that the level of overstress was not sufficient to produce fatigue concerns and concluded that the overstress condition was acceptable. However, GPUN also concluded that the overstress condition was not desirable and developed a modification of the drain line support configurations to make the lines more flexible and reduce the thermal expansion stresses to within code allowable limits. The modification was described in a letter, dated August 27, 1990, from GPUN Headquarters in Parsippany, New Jersey, to the TMI site. However, the modification was never implemented. GPUN could provide no documentation to demonstrate that the modification was ever properly dispositioned. In addition, GPUN's design verification process failed to identify a significant error in the 1990 analysis that resulted in GPUN underestimating the level of overstress in the pipe. GPUN indicated to the NRC, at the predecisional enforcement conference and during subsequent telephone conversations that when the error in the 1990 analysis was corrected, the stresses in the piping were approximately 100% above the code allowable. These failures led to the RCS being returned to service and operated in a degraded condition for the past five years without any additional evaluation, monitoring or inspection, until the support configuration was modified during the October 1995 refueling outage. Based on a revised calculation, performed by GPUN after the leak was identified, TMI implemented the modification that had been developed in 1990. 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 not been the subject of escalated enforcement actions within the last 2 years, the NRC considered whether credit was warranted for Corrective Action in accordance with the civil penalty assessment process in Section VI.B.2 of the Enforcement Policy. Credit for corrective actions is warranted because your corrective actions were both prompt and comprehensive. These actions, which were noted in the inspection report, your presentation at the predecisional enforcement conference, and in Licensee Event Report 95-003-00, dated October 9, 1995, included, but were not limited to: (1) implementation of a modification that satisfies B31.1 Code requirements; (2) documentation of the basis for disposition of analysis producing stresses beyond code specified allowables; (3) counseling of individuals involved in the modification implementation/ disposition; (4) continuing management emphasis on follow-up and close-out recommendations; (5) restricting certain individuals from performing design verifications; (6) performing further evaluation of root cause of calculation and design verification errors; and (7) retraining all engineers on the Design Verification Process during the first quarter of 1996. Therefore, to emphasize the importance of prompt and comprehensive correction of violations, I have been authorized, after consultation with the Director, Office of Enforcement, not to propose a civil penalty in this case. However, significant violations in the future could result in a civil penalty. A second violation occurred when GPUN performed a more refined ASME Section III calculation to disposition the pipe overstressed condition calculated in the 1990 B31.1 analysis. During the service life of the plant, the licensee is required, pursuant to 10 CFR 50.55a(g), to meet the inservice inspection requirements of ASME Section XI. For components or supports that do not meet ASME Section XI acceptance criteria, the licensee must perform a repair or replacement, or perform an evaluation to demonstrate the adequacy of the components or supports. In order to disposition the pipe overstressed condition, GPUN performed a calculation using part of the criteria in ASME Section III, subsection NB-3653.6, "Simplified Elastic-Plastic Discontinuity Analysis." Specifically, GPUN utilized NB-3653.6(c) equation 14, and concluded that the level of overstress would not cause a fatigue concern with the drain line piping. Although use of specific provisions of Section III is allowed for such dispositions, Section III, subsection NCA-1140, states that all related requirements must also be met. In this case, NB-3653.6 specifies several related requirements that must be met. Some examples of related requirements that were not met include NB-3653.6 equations 12 and 13, NB-3653.4, NB-3653.5, and NB-3653.7. In addition, NB-3653.6 provides rules for calculating the parameters used in the equations. GPUN's analysis did not incorporate all the related requirements, and did not follow the rules for calculating the parameters used in equation 14. The analysis performed was inadequate to demonstrate the adequacy of the piping and related supports. As noted previously, GPUN returned the lines to service in the as-found condition and operated from that time with no additional evaluation, monitoring, or inspection until the support configuration was modified in 1995. 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 IV. We further noted that, prior to and after the predecisional enforcement conference, you determined that there were errors in the calculation performed that had a significant impact on the acceptability of the supports involved and the drain line. 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(s), 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. The responses directed by this letter and the enclosed Notice are not subject to the clearance procedures of the Office of Management and Budget as required by the Paperwork Reduction Act of 1980, Pub. L. No. 96.511.
Sincerely,
Thomas T. Martin
Regional Administrator
Docket No. 50-289 Enclosure: Notice of Violation cc w/enclosure:
GPU Nuclear Corporation Docket No. 50-289
Three Mile Island, Unit 1 License No. DPR-50
EA 95-238
During an NRC inspection conducted on September 25-29, 1995 and October 10-11, 1995, violations of NRC requirements were identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," NUREG- 1600, the violations are listed below: A. 10 CFR Part 50, Appendix B, "Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants," Section III, "Design Control," requires, in part, that measures be established for the identification and control of design interfaces and for coordination among participating design organizations. Appendix B also requires, in part, that licensees establish design control measures that provide for verifying or checking the design adequacy. Contrary to the above, from 1990 through at least September 1995, measures were not established for the identification and control of design interfaces and for coordination among participating design organizations as required, nor did the licensee establish design control measures that provided for verifying or checking design adequacy. 1. Specifically, GPUN failed to control adequately a modification to the reactor coolant system (RCS) drain line piping. The modification was developed as a result of a 1990 GPUN structural analysis that demonstrated that the drain line piping was overstressed due to an improper support configuration. The modification was described in a letter, dated August 27, 1990, transmitted from GPUN Headquarters in Parsippany, New Jersey, to the TMI site. However, the modification was not implemented as of September 1995, and GPUN could provide no documentation to demonstrate that the modification was ever properly dispositioned. 2. GPUN's design verification process failed to identify a significant error in the 1990 analysis that resulted in underestimating the level of stress in the pipe. Specifically, the analysis indicated thermal expansion stresses approximately 4% above the allowables specified in the design code of record (USAS B31.1 1967). However, when the analytical error was corrected in 1995, the stresses were approximately 100% above the code allowables. (01013)This is a Severity Level III violation (Supplement I). B. 10 CFR 50.55a, "Codes and Standards," paragraph (g), "Inservice inspection requirements," requires that licensees of nuclear power plants meet applicable criteria in Section XI, Division 1, of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code "Rules for Inservice Inspection of Nuclear Power Plant Components." ASME Section XI requires, in part, that licensees perform inservice examinations of class 1 components, including supports. If the components or supports do not meet the examination acceptance criteria, Section XI requires that the licensee perform a repair or replacement, or perform further evaluation to demonstrate the adequacy of the components or supports. Contrary to the above, in 1988 and 1990, GPUN did not meet the applicable requirements in 10 CFR 50.55a, in that, during the performance of inservice inspection (ISI) examinations of pipe supports on the RCS drain lines, a class 1 component, GPUN identified distorted supports and failed to repair or replace or perform an adequate evaluation to establish the adequacy of the piping and supports. GPUN performed a structural analysis of the drain lines that demonstrated that the configuration of the supports did not allow for adequate pipe thermal expansion. Consequently, stress levels in the drain line piping exceeded the allowable stress values specified in the piping design code of record, USAS B31.1-1967, "Power Piping." GPUN utilized a later code, Section III subsection NB-3653.6, to disposition the overstressed piping. Paragraph NCA-1140 of Section III allows the use of specific provisions of the code but requires that all related requirements be met. The analysis performed by GPUN did not incorporate all related requirements of NB-3653.6 and was inadequate to demonstrate the adequacy of the piping and associated supports. (02014)This is a Severity Level IV violation (Supplement I). Pursuant to the provisions of 10 CFR 2.201, GPU Nuclear Corporation (Licensee) is hereby required to submit a written statement or explanation to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington D.C. 20555 with a copy to the Regional Administrator, Region I, and a copy to the NRC Resident Inspector at the facility that is the subject of this Notice, within 30 days of the date of the letter transmitting this Notice of Violation (Notice). This reply should be clearly marked as a "Reply to a Notice of Violation" and should include for each violation: (1) The reason for the violation, or if contested, the basis for disputing the violation, (2) the corrective steps that have been taken and the results achieved, (3) the corrective steps that will be taken to avoid further violations, and 4) the date when full compliance will be achieved. Your response may reference or include previous docketed correspondence, if the correspondence adequately addresses the required response. If an adequate reply is not received within the time specified in this Notice, an order or Demand for Information may be issued as to why the license should not be modified, suspended, or revoked, or why such other action as may be proper should not be taken. Where good cause is shown, consideration will be given to extending the response time. Under the authority of Section 182 of the Act, 42 U.S.C. 2232, this response shall be submitted under oath or affirmation. 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 King of Prussia, Pennsylvania |
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