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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 40963 | 17 August 2004 15:30:00 | 10 CFR 20.2201(a)(1)(ii) 10 CFR 74.11(a) 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | "Report of Missing Special Nuclear Material | This is a non-emergency Event Notification in accordance with 10 CFR 74.11 to inform the NRC of missing special nuclear material of low strategic significance. On July 16, 2004, Pacific Gas, and Electric (PG&E) notified the NRC of a material accountability discrepancy involving a portion of a spent fuel rod used at the Humboldt Bay Power Plant (HBPP) Unit 3 (reference NRC Event Notification 40877). The discrepancy in plant records called into question the location of three approximately 18-inch segments that were cut from a single spent fuel rod in a used fuel assembly (A-49) in 1968. PG&E initiated a comprehensive search of the on-site HBPP spent fuel pool (SFP), a review of plant and nuclear materials shipping records, and interviews with present and former employees and contractors to resolve the material accountability discrepancy and locate the unaccounted for fuel segments. On August 17, 2004, at 08:30 PDT, the HBPP Plant Staff Review Committee (PSRC) reviewed the results of the search of the SFP to-date and concluded that the search of the most likely locations for the unaccounted for fuel segments (storage containers within the SFP) and all easily accessible spaces in the SFP was thorough and complete and that the search had not located the unaccounted for fuel segments in the SFP. The PSRC also reviewed the results to-date of the in-progress review of plant records, interviews, and nuclear material shipping records and concluded that the relevant information obtained did not definitively identify the on-site or off-site location of the unaccounted for fuel segments. Though it remains probable that the unaccounted for fuel segments will ultimately be found in the SFP or shown to have been shipped to a facility licensed to reprocess or store nuclear materials, PG&E is conservatively considering these segments as missing and making this 1-hour non-emergency event notification in accordance with 10 CFR 74.11. PG&E will be issuing a press release later today describing the current status of this issue. PG&E has embarked upon a 'phase II' search of the remaining less-accessible SFP areas and will continue its review of plant records, nuclear materials shipping records (plant and waste repository records), and interviews of plant personnel to definitively locate the missing fuel segments. A supplemental LER will be provided to the NRC when the segments are located or when the phase II search is concluded. No evidence has been uncovered to support the possibility of theft or diversion of the unaccounted for fuel segments. Due to the high radioactivity of the material, to be handled safely, the segments would have to be encased in a heavy shielded container that would have to be moved with special handling equipment designed for this purpose, precluding an abrupt loss. Since plant start-up, HBPP has been equipped with a system of radiation monitors for the refueling building (where the SFP is located) with alarm setpoints that are capable of alerting plant personnel of the movement of highly radioactive material should the fuel segments have been removed from the SFP without being in a shielded container. This could not have occurred casually without plant staff or security personnel observing the movement. Because the three approximately 18-inch segments are not readily identifiable in the SFP, three possible scenarios exist. The highest probability is that the fuel segments are in a SFP area that is not readily accessible, and will be located during a more detailed search of these locations. The second highest probability is that the fuel segments were shipped offsite to an appropriately controlled and restricted facility for either analysis or reprocessing. The least probable location, but not yet capable of being ruled out, is that the fuel segments were inadvertently included in a shipment to a licensed, monitored, and restricted LLRW facility. Since these possible locations are licensed, monitored and restricted radiological control areas, the public health and safety has not been adversely affected. For additional information, refer to licensee event report (LER) 2004-001-00,'Three Missing Fuel Rod Segments,' dated August 16, 2004, and submitted in accordance with 10 CFR 20.2201(b)(2)(ii), (Reference H BL-04-020). NRC personnel at headquarters and in Region IV have been notified of the status of this issue. | ||
| ENS 40877 | 16 July 2004 20:00:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Press Release Will Be Issued at 1300 Pdt on 7/16/04 on the Material Accountability Discrepancy Involving a Portion of a Spent Fuel Rod Used at Humbolt Bay Power Plant Unit 3. | This is a non-emergency Event Notification made in accordance with 10 CFR 50.72(b)(2)(xi) to inform the NRC that a press release will be issued shortly informing the public of a nuclear material accountability discrepancy involving a portion of a spent fuel rod used at Pacific Gas and Electric's (PG&E) Humboldt Bay Power Plant (HBPP) Unit 3. HBPP Unit 3 has been shut down since 1976 and in SAFSTOR since 1988. In the process of reviewing records and verifying the contents of the spent fuel pool (SFP) in preparation for loading materials into dry cask storage, PG&E has identified a discrepancy in plant records that calls into question the location of three segments of a portion of a single spent fuel rod removed from assembly A-49 in 1968. Meeting records produced in 1968 indicate that the segments have been stored in the SFP since 1968. However, 1969 plant shipping records indicate that the entire A-49 assembly was included as part of a larger shipment of several spent fuel assemblies sent for offsite reprocessing in 1969. The 1969 shipping records make no mention that one rod had been removed from the A-49 assembly that was shipped. A more detailed review of records and a complete search of the SFP is underway to establish and verify the location of the three fuel rod segments. Since 2003, PG&E plant personnel have been conducting a complete review of plant records and cataloging the contents of the SFP in preparation for the planned decommissioning of the plant, including the transfer of spent fuel into an onsite Independent Spent Fuel Storage Installation. On June 23, 2004, plant personnel found Onsite Review Committee (OSRC) meeting minutes dated October 2, 1968, that described cutting one fuel rod from fuel assembly A-49 into three 18 inch segments that were placed into a small container (1 -1 /2 inch, schedule 40 pipe) in preparation for shipment to the Battelle Memorial Institute in Columbus, Ohio, for analysis. The meeting minutes further state that the shipment to Battelle was subsequently cancelled and the small container with the three 18-inch fuel rod segments was returned to the SFP, with the specific location in the SFP unidentified. The minutes also state that the remnants of the 84 inch long fuel rod from which the three 18-inch segments were cut were placed in the central storage container within the SFP. On June 25, 2004, after further research, PG&E found shipping records indicating that on August 6, 1969, the entire A-49 fuel assembly was shipped to Nuclear Fuel Services Inc. (NFS) in West Valley, New York, for reprocessing. No mention was made in the shipping record that a rod had been removed from the A-49 fuel assembly. This contradicts the OSRC meeting minutes that indicate one fuel rod from A-49 remains in the SFP. Further review of records did not resolve the discrepancy, so on June 28, 2004, PG&E verbally notified the Nuclear Regulatory Commission, Region IV office of the potential discrepancy in records and the uncertainty regarding the specific location of the fuel rod removed from A-49. On July 7, 2004, PG&E began a physical search of the central storage container in the SFP for the remnant portions of the A-49 rod, as well as the three 18-inch segments. On July 9-11, 2004, PG&E identified what appears to be the remnant portions of the A-49 rod in the central storage container in the SFP as specified in the 1968 OSRC meeting minutes. However, the three 18-inch segments were not found in the central storage container. PG&E is continuing with a thorough search of the remaining storage containers in the SFP as well as other possible areas in the SFP where the three fuel rod segments may be located. The search is a painstaking process performed under tight procedural guidance that could take at least several weeks to complete. NRC inspectors have been onsite during the week of July 12 and are fully aware of the status of these inspections. In addition, PG&E is continuing its review of plant records as well as interviewing plant personnel who were onsite during the 1968-1969 period to find further evidence that may expedite location of the three fuel rod segments. This notification also satisfies the 30-day notification requirement of 10 CFR 20.2201(a)(1)(ii). If ongoing searches fail to confirm the location of the material, a subsequent written report will be made in accordance with 10 CFR 20.2201(b). |