|
---|
Category:Letter
MONTHYEARML24169A3302024-06-17017 June 2024 UC Davis MNRC Change in Address of Level 1 Management ML24143A1422024-05-22022 May 2024 University of California-Davis Mcclellan Nuclear Research Center - 2023 Annual Report (Cover Letter) ML24094A0682024-04-0404 April 2024 University of California-Davis Mcclellan - Change of Facility Backup Project Manager IR 05000607/20242012024-03-28028 March 2024 University of California-Davis - U.S. Nuclear Regulatory Commission Routine Inspection Report No. 05000607/2024201 ML24032A1352024-02-0101 February 2024 Examination Confirmation Letter No. 50-607/OL-24-01, University of California-Davis ML23332A7062023-11-27027 November 2023 University of California, Davis Mcclellan Nuclear Research Center (MNRC) License Holder Appointment ML23263A9762023-09-22022 September 2023 Regents of the Ucd Issuance of Amendment No. 10 to Renewed Facility Operating License R-130 ML23262B5202023-09-19019 September 2023 University of California Davis Mcclellan Nuclear Research Center (Mnrc), Docket Number 50-607, License Number R-130, Supplement to License Amendment Request 2023-02 ML23258A2422023-09-15015 September 2023 University of California Davis Mcclellan Nuclear Research Center (Mnrc), Docket Number 50-607, License Number R-130, License Amendment Request 2023-02 ML23222A1872023-08-10010 August 2023 Univ. of California, Davis, 14-Day Written Follow-up to Call Made to the HOO (EM 56643) on July 28th 2023 ML23095A0652023-03-14014 March 2023 American Nuclear Insurers, Notice of Cancellation Rescinded ML23045A0452023-03-0202 March 2023 Regents of the University of California - Issuance of Amendment No. 9 to Renewed Facility Operating License No. R-130 to Amend the Technical Specifications for the University of California - Davis/Mcclellan Nuclear Research Center ML23073A3992023-03-0101 March 2023 University of California Davis Mcclellan Nuclear Research Center (MNRC) License Holder Appointment IR 05000607/20232012023-02-23023 February 2023 University of California - Davis U.S. Nuclear Regulatory Commission Routine Inspection Report 05000607/2023201 ML23045A3202023-02-14014 February 2023 14 Day Notification to Document Control Desk of Event 56331 Made to NRC Operations Center by UC Davis MNRC on February 1st at 1651 Est ML23039A2072023-02-0808 February 2023 University of California Davis Mcclellan Nuclear Research Center (Mnrc), Docket Number 50-607, License Number R-130, License Amendment Request 2023-01 IR 05000607/20222022022-12-28028 December 2022 University of California-Davis - Us Nuclear Regulatory Commission Routine Inspection Report No. 05000607/2022202 ML22214B8292022-11-21021 November 2022 Letter to Ucd with Renewed Facility Operating License ML22213A1622022-10-18018 October 2022 FRN Re UCD-MNRC Environment Assessment ML22213A1692022-10-18018 October 2022 Regents of the University of California - Environmental Assessment and Finding of No Significant Impact Regarding Renewal of Facility Operating License No. R-130 for the University of California - Davis/Mcclellan Nuclear Research Center ML22193A2532022-07-12012 July 2022 Univ. of California-Davis - Summary of the Analysis of Changes Made to the MNRC Emergency Plan Under the Provisions of 10 CFR 50.54q ML22181B0822022-06-30030 June 2022 University of California-Davis/McClellan Nuclear Research Center, Response to NRC Request for Additional Information Letter Dated June 24th, 2022 Regarding License Renewal Application ML22174A2932022-06-28028 June 2022 Regents of the University of California - Report on the Regulatory Audit License Renewal Application for the University of California - Davis/Mcclellan ML22173A2092022-06-24024 June 2022 Regents of the University of California; Request for Additional Information Regarding License Renewal Application for the University of California ML22174A4222022-06-23023 June 2022 Additional Response to NRC Request for Additional Information Letter Dated June 3rd 2022 Regarding License Renewal Application for the University of California-Davis/McClellan Nuclear Research Center ML22173A2022022-06-22022 June 2022 Response to NRC Request for Additional Information Letter Dated June 3rd 2022 Regarding License Renew Al Application for the University of California - Davis/Mcclellan Nuclear Research Center ML22172A1982022-06-21021 June 2022 UC Davis MNRC Submission of Technical Specification in Support of License Renewal Application ML22154A5442022-06-0303 June 2022 Univ. of CA - Davis, MNRC Submittal of Technical Specification in Support of License Renewal Application ML22146A1942022-06-0303 June 2022 Regents of the University of California - RAI Regarding License Renewal Application for the University of California - Davis/Mccellan Nuclear Research Center ML22154A5482022-06-0303 June 2022 University of California - Davis, Submittal of MNRC 2021 Annual Report ML22137A2602022-05-26026 May 2022 University of California - Davis - Closure of Confirmatory Action Letter No. NRR 02 002 on the Site-Specific Compensatory Measures Implementation Plan IR 05000607/20222012022-05-26026 May 2022 University of California-Davis U.S. Nuclear Regulatory Commission Routine Inspection Report No 05000607/2022201 ML23142A3032022-05-22022 May 2022 Univ. of California - Davis, Submittal of MNRC 2022 Annual Report ML22109A1042022-05-0303 May 2022 Regents of the Univ. of CA - Review of the Physical Security Plan in Support of License Renewal Application for the Univ. of CA-Davis/McCellan Nuclear Research Center ML22089A1582022-03-30030 March 2022 UC Davis MNRC Response to NRC Staff Request for Additional Information Regarding Licensing Renewal Application Letter Issued February 8th, 2022 ML22041A3782022-02-28028 February 2022 Regents of the University of California - Determination of Acceptability and Sufficiency for Docketing and Opportunity for Hearing Regarding the License Renewal Application for the University of California - Davis/Mcclellan Nuclear Research ML22038A1402022-02-0808 February 2022 Regents of the University of California - Request for Additional Information Regarding License Renewal Application for the University of California - Davis/Mcclellan Nuclear Research Center ML22026A2862022-02-0202 February 2022 Regents of the University of California - Regulatory Audit Re License Renewal Application for the University of California - Davis/Mcclellan Nuclear Research Center Training, Research, Isotope, General Atomics Nuclear Reactor ML22014A1272022-01-11011 January 2022 50 .54P Submittal of the Ucd/Mnrc Physical Security Plan for University of California, Davis Mcclellan Nuclear Research Center (Ucd/Mnrc), Docket No. 50-607, Facility Operating License No. R-130 the ML21300A3922021-12-23023 December 2021 University of California-Davis U.S. Nuclear Regulatory Commission Routine Inspection Report No. 05000607/2021202 ML21351A3172021-12-17017 December 2021 UC Davis MNRC Response to NRC Staff Request for Additional Information Regarding Licensing Renewal Application Letter Issued November 30th, 2021 IR 05000607/20212022021-12-0606 December 2021 University of California-Davis - Nuclear Regulatory Commission Security Inspection Report No. 05000607/2021202 Cover Letter ML21316A1162021-11-30030 November 2021 Regents of the University of California - Request for Additional Information Regarding License Renewal Application for the University of California-Davis Mccellan Nuclear Research Center ML21252A7572021-10-0505 October 2021 University of California-Davis/MCCLELLAN - Approval of the Revised Nuclear Radiation Center Selection and Training Plan ML21265A5412021-09-22022 September 2021 UC Davis MNRC Cover Letter for Response to Request for Supplemental Information ML21250A3662021-09-14014 September 2021 Regents of the University of California Report on the Regulatory Audit License Renewal Application for the University of California Davis/Mcclellan Nuclear Research Center Triga Nuclear Reactor ML21175A3342021-06-22022 June 2021 Transmittal of University of California, Davis, MNRC 2020 Annual Report IR 05000607/20212012021-05-0707 May 2021 University of California-Davis - U. S. Nuclear Regulatory Commission Routine Inspection Report No. 05000607/2021201 ML21029A1472021-01-25025 January 2021 UC Davis Mcclellan Nuclear Research Center - 50.54P Submittal of the Ucd/Mnrc Physical Security Plan ML20338A2622020-12-10010 December 2020 NRR-106 University of California Davis License Renewal - Regulatory Audit Letter and Plan 2024-06-17
[Table view] Category:Written Event Report (30 or 60 day)
MONTHYEARML23222A1872023-08-10010 August 2023 Univ. of California, Davis, 14-Day Written Follow-up to Call Made to the HOO (EM 56643) on July 28th 2023 ML23045A3202023-02-14014 February 2023 14 Day Notification to Document Control Desk of Event 56331 Made to NRC Operations Center by UC Davis MNRC on February 1st at 1651 Est 2023-08-10
[Table view] |
Text
UNIVERSITY OF CALIFORNIA, DAVIS BERKELEY
- SAN FRANCISCO SANTA BARBARA
- SANTA CRUZ McClellan Nuclear Research Center UNIVERSITY OF CALIFORNIA Davis Davis (916)-614-6200 Tuesday February 14th 2023 Attn: Document Control Desk US Nuclear Regulatory Commission Washington, D.C. 20555-01
Subject:
14 Day Notification to Document Control Desk of Event #56331 Made to NRC Operations Center by UC Davis MNRC on February 1st at 1651 EST.
Summary of Event: During early summer of 2022 MNRC was working with the NRC staff to finalize the technical specification as part of the facilitys relicensing effort. MNRC staff proposed the limits on technical specification section 3.3 item number 4 as the limits set forth in 10 CFR 20 appendix B table 3. This limit was consistent with other similar research reactors and became part of MNRCs technical specifications on 11/21/22 when the new 20-year license was issued.
When proposing this new technical specification limit, MNRC Staff examined historical values for all non-tritium nuclides having half-lives greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. These nuclides are assayed at MNRC via high resolution gamma-ray spectroscopy. For these non-tritium nuclides, MNRC determined that the proposed limits could be satisfied. Separately, MNRC staff looked at the tritium concentration levels that are provided to MNRC via a private non-UC Davis laboratory. The latest result from this private laboratory was reviewed and confirmed MNRC would meet the new tritium limit of 0.01 uCi/ml by having a tritium concentration of approximately 1/40th of this value. Only this single tritium concentration report was checked as historical tritium levels were known to vary little from year to year.
On 1/31/2023 (while the reactor was shut down) it was discovered that the private laboratory results were incorrect and were mistakenly underreported by a factor of 100. As a result, MNRCs primary cooling water tritium concentration was determined to be approximately 2.5 times the new technical specification limit.
The exceeding of this limit was immediately reported to the NRC Operations Center (Event #56331) and reactor operations were suspended. A more extensive data review shows that MNRCs primary water tritium levels, during the past 10 years of 1 MW single-shift operation, were highly consistent ranging from a maximum of 0.026 uCi/ml to a minimum of 0.017 uCi/ml with an average concentration of 0.022 uCi/ml.
There has been no increase in the amount of tritium in MNRCs primary cooling water nor has any primary cooling water been released from the reactor tank since the new technical specification took effect.
Immediate Action: The UC Davis MNRC Director (level 2 management) instructed all licensed reactor operators that the reactor was not to be operated until further notice. Per MNRCs technical specification section 6.7.2 the NRC Operations Center was notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the discovery of having likely operated in violation of a limiting condition for operation from 11/21/22 until 1/30/23. The facilitys NRC program manager, backup program manager, inspector, UC Davis MNRC Nuclear Safety Committee chair,
and UC Davis MNRC license holder (level 1 management) where all notified of the event on 2/1/2023. It was determined that this event had no safety or security consequences and that no additional immediate actions were required by the MNRC staff.
Corrective Action and Event Resolution: As MNRC cannot lower the concentration of tritium in the primary cooling water, MNRC cannot operate under the conditions of technical specification 3.3 item 4. After consultation with NRC and MNRC staff, it was determined that a license amendment request (LAR) was the best option for resuming operation. A LAR was submitted to the NRC on 2/8/2023 and is currently under review. The LAR asks that MNRCs technical specification section 3.3 item number 4 be changed to allow for reactor operation so long as tritium levels in the primary cooling water do not exceed 0.05 uCi/ml. The current technical specifications require tritium concentrations under 0.01 uCi/ml (based on 10 CFR 20 appendix B table 3) in order to operate the reactor. The analysis provided in the LAR provides reasonable assurance that the proposed change does not represent any undue risk to the public or environment.
The event will reach final resolution when the license amendment is issued by the NRC. This event continues to have no adverse effect on safety or security.
Affirmation: I declare under penalty of perjury that the foregoing is true and correct executed on February 14th 2023.
Digitally signed by Wesley frey Wesley frey Date: 2023.02.14 13:13:45
-08'00' Wesley Frey PhD CHP MNRC Facility Director