05000255/FIN-2015013-03
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Finding | |
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Title | Failure to perform the surveillance test within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or perform a risk evaluation to complete the surveillance at a later date |
Description | On June 25, 2012, the U.S. Nuclear Regulatory Commissions Office of Investigations initiated an investigation to determine whether personnel at the Palisades Nuclear Power Plant (Palisades) deliberately failed to provide complete and accurate information to the NRC regarding a safety injection and refueling water storage tank (SIRWT) leak. The investigation was completed on March 10, 2015. On May 18, 2011, Condition Report (CR) PLP201102491 was initiated when leakage from the ceiling in the Palisades main control room was identified following heavy rains in the area. Chemistry analysis of this leakage revealed several radioactive isotopes including Cobalt58, a short-lived isotope found in the primary coolant. After repairs were made to the auxiliary building roof, leakage into the control room stopped and did not recur. The Palisades auxiliary building contains the main control room with the catacombs directly above it, and the SIRWT is located on the auxiliary building roof directly above catacombs. On May 27, 2011, a robotic visual inspection was performed in the catacombs above the control room and below the SIRWT to look for the source of the leakage. This inspection identified boric acid deposits on the catacombs ceiling and floor, and on piping components. On June 2, 2011, a direct visual inspection (VT2) was performed in the catacombs that identified two active leaks: one from the catacombs ceiling and one from a 3-inch SIRWT piping flange in the catacombs. Condition Report PLP201102738 was initiated for the active flange leak on the 3-inch SIRWT piping flange. The flange bolting material was carbon steel, which is susceptible to boric acid corrosion. In accordance with procedure EM0920, Boric Acid Corrosion Control Program, a boric acid evaluation was required to determine the current and future integrity of the bolts. However, the VT2 data sheet did not contain information on the material condition of the flange bolting. The CR documented a minor (less than one drop per minute) flange leak on the 3-inch piping flange, but did not identify any through-wall leakage or component wastage. It stated that no degraded or nonconforming condition existed per procedure ENOP104, Operability Determination Process, and T58 (SIRWT) remained operable. Condition Report PLP201102740 was written for the active leak from the catacombs ceiling. The operability determination for this CR was copied directly from CR PLP201102738, which was written to document leakage from the 3-inch piping flange, a separate and different condition. The operability determination did not address the actual CR condition, which was a leak from the ceiling; and therefore, possibly the SIRWT. On June 8, 2011, a Kepner-Tregoe (KT) team was formed to investigate and identify potential and most likely leakage source. Leakage collection and analysis of the catacombs ceiling leak took place on almost a daily basis since the initial catacombs inspection. However, the analysis results of the leakage varied throughout the collection timeframe. The team could not identify the source of the leakage with 100% certainty. On June 13, 2011, a contracted engineering firm, Structural Integrity Associates (SIA), was requested to propose a contract to evaluate a potential SIRWT leak. On June 16, 2011, CR PLP201103021 was written to document that (RT71M) for SIRWT and associated piping Code pressure surveillance test had not been conducted at the frequency required by the Code. The operability statement stated that the RT71M surveillance was required by Technical Specifications (TSs), but incorrectly stated that the surveillance had been completed on June 2, 2011, thereby meeting the surveillance requirements. On June 30, 2011, the engineering Code program supervisor issued an e-mail stating that if short-lived radioisotopes were identified in leakage samples, the probability of the SIRWT being the leak source was "essentially 100%." Short-lived isotopes had been identified in samples throughout the sampling timeframe; they were first identified in the May 20, 2011, sample. On July 27, 2011, the KT team was disbanded. On August 2, 2011, an industry chemistry consultant was contacted to independently analyze the leakage data. On September 16, the consultant sent an e-mail to the chemistry manager stating that the SIRWT was the likely source of the leakage. On September 19, 2011, in an e-mail response to questions regarding his conclusions, the consultant replied that there is never 100% certainty in any evaluation of this type. However, the SIRWT isotopic analysis matched up much better than any of the other possible sources. On September 25, 2011, the chemistry manager e-mailed the former K-T team managers and stated that, although 100% certainty could not be assured, the source of the leakage was the SIRWT. On December 5, 2011, Structural Integrity Associates Calculation 1100772.301 requested on June 13, 2011, was approved by Palisades. On February 15, 2012, a draft operability determination using the SIA calculation was developed by Engineering as a contingency. On February 16, 2012, CR PLP201201091 was generated by Operations to perform an operability evaluation on the SIRWT, since it was the suspected source of the catacombs leakage. When correlating the tritium levels in the SIRWT to the catacombs in-leakage tritium levels, the correlation was sufficient to suspect SIRWT leakage. The CRs operability determination concluded that the SIRWT was operable, using the engineering contingency evaluation developed the previous day. Repairs to the SIRWT were completed during the March 2012 refueling outage; however, after the outage, additional leakage was identified from the SIRWT and monitored using the leakage acceptance criteria developed in the previous SIA calculation. Leakage progressively worsened until July 2012 when the plant was shut down to conduct additional repairs. The tank floor was replaced during the 2013 fall Refueling Outage. Based on the evidence gathered in the OI investigation, it appears that four individuals willfully violated NRC requirements by failing to follow site corrective action procedures, when it became known to the individuals that the leakage was most likely originating from the SIRWT. Specifically, these inactions caused the licensee to be in apparent willful violation of Title 10 of the Code of Federal Regulations, Part 50, Appendix B, Criterion V, for their failure to follow procedure ENLI102, Corrective Action Process. Two other apparent violations were also identified. The first was the failure to follow procedure ENOP104, Operability Determination Process. Specifically, the licensee failed to perform an adequate operability determination on an active leak from the catacombs ceiling and again on an active leak from a SIRWT piping flange. The second apparent violation was for the licensees failure to meet the requirement of TS surveillance requirement Section SR 3.0.3. Specifically, when the licensee identified surveillance procedure RT71M, the surveillance to conduct ASME inservice pressure tests of the SIRWT and associated piping, had not been performed within its required schedule, the licensee failed to perform the test within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or perform a risk evaluation to complete the surveillance at a later date. |
Site: | Palisades |
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Report | IR 05000255/2015013 Section 4OA5 |
Date counted | Mar 31, 2015 (2015Q1) |
Type: | AV: |
cornerstone | Mitigating Systems |
Identified by: | NRC identified |
Inspection Procedure: | |
Inspectors (proximate) | P Louden |
INPO aspect | |
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Finding - Palisades - IR 05000255/2015013 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Palisades) @ 2015Q1
Self-Identified List (Palisades)
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