ML21050A251

Submittal of Annual Operating Report for the University of Missouri-Columbia Research Reactor as Required by MURR Technical Specification 6.6.e

ML21050A251
Person / Time
Site:	University of Missouri-Columbia
Issue date:	02/19/2021
From:	Meffert B, Robertson J Univ of Missouri
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML21050A251 (37)

Text

mu niversity of Missouri Research Reactor Center 1513 Research Park Drive Columbia, MO 65211 PHONE 573-882-4211 WEB murr.missouri .edu February 19, 2021 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001

REFERENCE:

Docket 50-186 University of Missouri-Columbia Research Reactor Renewed Facility Operating License No. R-103

SUBJECT:

Submittal of annual operating report for the University of Missouri-Columbia Research Reactor as required by MURR Technical Specification 6.6.e Enclosed is a copy of the 2020 Reactor Operations Annual Report for the University of Missouri-Columbia Research Reactor (MURR). This document is being submitted to the U.S. Nuclear Regulatory Commission in accordance with the MURR Technical Specification 6.6.e.

If you have any questions regarding the contents of this report, please contact Bruce Meffert at MeffertB@missouri.edu or by calling (573) 882-5118.

ENDORSEMENT:

Sincerely, Reviewed and Approved, Reactor Manager Reactor Facility Director BAM/jlm Enclosure cc: Mr. Craig Bassett, U.S. NRC Mr. Geoffrey Wertz, U.S. NRC

UNIVERSITY OF MISSOURI-COLUMBIA RESEARCH REACTOR REACTOR OPERATIONS ANNUAL REPORT January 1, 2020 through December 31, 2020

UNIVERSITY OF MISSOURI-COLUMBIA RESEARCH REACTOR REACTOR OPERATIONS ANNUAL REPORT January 1, 2020 through December 31, 2020 Compiled by the Staff of MURR Submitted by:

Reviewed and approved by:

Reactor Facility Director

UNIVERSITY OF MISSOURI-COLUMBIA RESEARCH REACTOR REACTOR OPERATIONS ANNUAL REPORT January 1, 2020 through December 31, 2020 INTRODUCTION The University of Missouri Research Reactor (MURR) is a multi-disciplinary research and education facility providing a broad range of analytical, materials science, and irradiation services to the research community and the commercial sector. Scientific programs include research in archaeometry, epidemiology, materials science, plant science, nuclear medicine, radiation effects, radioisotope studies, targeted radiotherapy, and nuclear engineering; as well as research techniques including neutron activation analysis, neutron scattering, and gamma-ray imaging. The heart of this facility is a pressurized, graphite and beryllium reflected, open pool-type, light water moderated and cooled, heterogeneous reactor designed for operation at a maximum steady-state power level of 10 Megawatts thermal

- the highest-powered university-operated research reactor in the United States.

The Reactor Operations Annual Report presents a summary of reactor operating experience for calendar year 2020.

Included within this report are changes to MURR Reactor Operations and Reactor Health Physics procedures, revisions to the Safety Analysis Report (SAR), facility modifications, new tests and experiments, reactor physics activities, and environmental and health physics data.

This report is being submitted to the U.S. Nuclear Regulatory Commission (NRC) to meet the administrative requirements of MURR Technical Specification 6.6.e.

ACKNOWLEDGMENTS The success of MURR and its scientific programs is due to the dedication and hard work of many individuals and organizations. Included within this group are: the University of Missouri (MU) administration; the governing officials of the State of Missouri; the Missouri State Highway Patrol (MSHP); the City of Columbia Police Department (CPD);

the University of Missouri Police Department (MUPD); the Federal Bureau of Investigation (FBI); our regulators; those who have provided funding, including the Department of Energy (DOE), the National Nuclear Security Administration (NNSA), the National Science Foundation (NSF), and the NRC; Argonne National Laboratory (ANL);

Idaho National Laboratory (INL); Sandia National Laboratories (SNL); the researchers; the students; the Columbia Fire Department (CFD); the MU Campus Facilities organization; the Nuclear Energy Institute (NEI); members of the National Organization of Test, Research and Training Reactors (TRTR); and many others who have made, and will continue to make, key contributions to our overall success. To these individuals and organizations, the staff of MURR wishes to extend its fondest appreciation.

Some of the major facility projects that were supported by Reactor Operations during this past calendar year included:

(1) replacement of the drive motor for primary coolant system pump P-501A; (2) replacement of the resin regeneration system with a resin handling system; (3) addition of the ability to response check select primary and pool coolant temperature channels prior to reactor startup; (4) replacement of the detectors and cabling for nuclear instrumentation signal processor nos. 1 and 2; (5) replacement of several process instrumentation incandescent valve and pump status indicators with light emitting diodes; (6) replacement of the regulating blade drive mechanism with a new and improved design; (7) installation of borated shielding plugs in the thermal column; (8) installation of underwater i

lighting in the reactor pool; (9) completion of a Type B radioactive waste shipment; (10) installation of additional isolation valves in the pneumatic tube system; (11) replacement of graphite reflector elements 5A and 5B; (12) replacement of the regulating blade offset mechanism; (13) replacement of the transmitter for primary coolant heat exchanger inlet resistance temperature detector channel TE-901B; and (14) replacement of emergency pool fill valve EPF-1.

The facility continues to actively collaborate with the NNSA Office of Material Management and Minimization (M3)

Reactor Conversion Program and five other U.S. high-performance research and test reactor facilities, including one critical facility, that use highly enriched uranium (HEU) fuel to find a suitable low-enriched uranium (LEU) fuel replacement. Although each one of the five high-performance reactors is responsible for its own feasibility and safety studies, regulatory interactions, fuel procurement, and conversion, there are common interests and activities among all five reactors that will benefit from a coordinated, working-group effort. This past year, work was focused on (1) the compatibility of LEU fuel stored in HEU fuel locations - both in- and ex-pool - specifically analyzing criticality, capacity and planning, structural integrity, dose rates, and natural convection cooling; and (2) the low power physics startup test plan, which includes startup tests and analyses that predict the results of those startup tests and acceptance criteria for comparison of measurements to predicated or expected values.

Reactor Operations management also wishes to commend one individual who received his Reactor Operator certification from the NRC. This individual participated in a rigorous training program of classroom seminars, self-study, and on-the-job training. The results of this training are confident, well-versed, decisive individuals capable of performing the duties of licensed staff during normal and abnormal situations.

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TABLE OF CONTENTS Section Title Pages I. Reactor Operations Summary ............................................................................................... I-1 through 6 II. MURR Procedures ...............................................................................................................II-1 through 7 A. Changes to Reactor Operations Procedures B. Changes to Emergency Plan Implementing Procedures C. Changes to Radiological Control, Byproduct Material Shipping, and Preparation of Byproduct Material for Shipping Procedures III. Revisions to the Safety Analysis Report ............................................................................ III-1 through 2 IV. Plant and System Modifications ......................................................................................... IV-1 through 5 V. New Tests and Experiments ................................................................................................................. V-1 VI. Special Nuclear Material and Reactor Physics Activities .................................................................. VI-1 VII. Radioactive Effluent.......................................................................................................... VII-1 through 2 Table 1 - Sanitary Sewer Effluent Table 2 - Stack Effluent VIII. Environmental Monitoring and Health Physics Surveys ................................................. VIII-1 through 6 Table 1 - Summary of Environmental Set 97 - Spring 2020 Table 2 - Summary of Environmental Set 98 - Fall 2020 Table 3 - Environmental TLD Summary Table 4 - Number of Facility Radiation and Contamination Surveys IX. Summary of Radiation Exposure to Facility Staff, Experimenters, and Visitors ............................... IX-1 iii

SECTION I REACTOR OPERATIONS

SUMMARY

January 1, 2020 through December 31, 2020 The following table and discussion summarize reactor operations during calendar year 2020.

Full Power Full Power Month Full Power Hours Megawatt Days

(% of total time) (% of scheduled*)

January 667.84 278.40 89.8 100.5 February 625.81 260.99 89.9 100.7 March 667.21 278.12 89.7 100.4 April 643.23 268.13 89.3 100.1 May 679.22 283.08 91.3 102.2 June 638.07 265.93 88.6 99.3 July 679.32 283.17 91.3 102.3 August 652.53 272.00 87.7 98.2 September 659.05 274.67 91.5 102.5 October 673.43 280.68 90.5 101.4 November 633.32 263.96 88.0 98.5 December 677.66 282.52 91.1 102.0 Total for the Year 7,896.69 3,291.65 89.90 100.69 MURR is scheduled to average at least 150 hours0.00174 days <br />0.0417 hours <br />2.480159e-4 weeks <br />5.7075e-5 months <br /> of full power operation per week. Total time is the number of hours in the month or year listed.

JANUARY 2020 The reactor operated continuously in January with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, and one unscheduled/unplanned power reduction.

On January 27, with the reactor operating at a power level of 5 MW during a reactor startup, a manual reactor shut down was performed in accordance with operating procedure OP-RO-220, Reactor Shutdown or Power Reduction, due to a higher-than-normal indication from the pool coolant heat exchanger outlet resistance temperature detector (RTD). Further investigation revealed that temperature channel TE-901D was indicating 6 °F higher than its associated pool coolant heat exchanger outlet thermocouple indication. The transmitter for temperature channel TE-901D was replaced, and compliance procedure CP-8C, Pool Coolant System RTDs 901C/D, was completed satisfactorily as post-maintenance testing. Permission to restart the reactor was obtained from the Reactor Manager, and the reactor was returned to 10 MW operation.

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Major maintenance items for the month included: loading new de-ionizing bed W and placing it on pool coolant system service; replacing the drive motor for primary coolant system pump P-501A; and completing Modification Record 19-01, Addendum 1, Replacement of Regeneration System with Resin Handling System.

FEBRUARY 2020 The reactor operated continuously in February with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, two shutdowns for physics measurements, and two unscheduled/unplanned power reductions.

On February 22, with the reactor operating at 10 MW in the automatic control mode, a Channel 4, 5, or 6 Hi Power Rod Run-In was automatically initiated and then subsequently reset to investigate the cause. While reviewing the nuclear instrumentation power range monitor (PRM) and intermediate range monitor (IRM) chart recorders, the Lead Senior Reactor Operator (LSRO) noticed some erratic behavior displayed on signal processor no. 1 (SP-1) PRM-4, IRM-2, and source range monitor chart recorders. Due to this erratic behavior, the LSRO determined SP-1 was not functioning properly and immediately initiated a manual reactor scram. All immediate and subsequent actions of reactor emergency procedure REP-5, Nuclear Instrument Failure, were completed. Investigation revealed that SP-1 fission chamber detector cable may have been touching the fission chamber drywell, which could potentially cause the erratic signal behavior of SP-1. The cable was adjusted to ensure it was not touching the drywell. Permission to restart the reactor was obtained from the Acting Reactor Manager, and the reactor was returned to 10 MW operation.

Later that day on February 22, with the reactor operating at 10 MW in the automatic control mode, a Channel 4, 5, or 6 Hi Power Scram was automatically initiated. All immediate and subsequent actions of reactor emergency procedure REP-2, Reactor Scram, were completed. Investigation revealed that SP-1 fission chamber or its associated cable had failed, and both the detector and cable were replaced. Post-maintenance testing following fission chamber and cable replacement was completed satisfactorily. Permission to restart the reactor was obtained from the Acting Reactor Manager, and the reactor was returned to 10 MW operation.

Major maintenance items for the month included: replacing wiring between a terminal board and the transmitter for pool coolant system temperature channel TE-901D; completing Modification Record 01-04, Addendum 13, Addition of a Single Point Calibration Reference to the Reactor Inlet and Outlet Temperature Channels (TE 901A/B) and to the Pool Coolant Heat Exchanger Inlet and Outlet Temperature Channels (TE 901C/D); performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-200, Measurement of Differential Worth of a Shim Blade, RTP-11(D); replacing nuclear instrumentation SP-1 fission chamber and cabling; replacing graphite reflector element 5B; and performing two reactivity worth measurements in accordance with reactor physics procedure RP-RO-201, Measurement of Reactivity Worth of Flux Trap Loadings or Individual Samples, RTP-17(B).

MARCH 2020 The reactor operated continuously in March with the following exceptions: five shutdowns for scheduled maintenance and/or refueling, and one shutdown for physics measurement. There were no unscheduled/unplanned power reductions.

Major maintenance items for the month included: loading new de-ionizing bed P and placing it on pool coolant system service; upgrading several process instrumentation valve and pump status indicators in the instrument cabinet from incandescent bulbs to light emitting diodes; and performing a reactivity worth measurement in accordance with I-2

reactor physics procedure RP-RO-201, Measurement of Reactivity Worth of Flux Trap Loadings or Individual Samples, RTP-17(B).

APRIL 2020 The reactor operated continuously in April with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, and two unscheduled/unplanned power reductions.

On April 8, with the reactor operating at 10 MW in the automatic control mode, a manual reactor scram was initiated upon discovery that the regulating blade drive mechanism was not operating. All immediate and subsequent actions of reactor emergency procedures REP-2, Reactor Scram, and REP-7, Rod Position Indication System Failure, were completed. The regulating blade drive mechanism was removed and transferred to the Instrumentation Support Shop for further inspection and troubleshooting. Examination revealed a broken pin inside the regulating blade drive mechanism gearbox, which holds the drive gear to the gearbox output shaft. Therefore, the regulating blade drive mechanism motor could operate, but no corresponding movement of the regulating blade occurred because the gear was spinning freely on the gearbox output shaft. After replacing the regulating blade drive mechanism gearbox and placing the rod position indication (RPI) encoder drive chain back on its associated sprockets, the RPI encoder drive chain alignment and tension were adjusted. The Regulating Blade Operation And Rod Run-In Function Test portion of form FM-57, Long Form Startup Checksheet, was completed satisfactorily as a pre-startup final test of proper operation of the regulating blade drive mechanism and its geared rotary limit switch assembly. In accordance with Technical Specification (TS) 6.6.c, permission to restart the reactor was obtained from the Reactor Facility Director, and the reactor was returned to 10 MW operation. Failure of the regulating blade and the regulating blade 10%

withdrawn rod run-in function during reactor operation resulted in deviations from TSs 3.2.a and 3.2.f.8, and Licensee Event Report No. 20-01 was submitted to the NRC on April 20, 2020.

On April 9, with the reactor operating at 10 MW in the automatic control mode, a manual reactor scram was initiated upon discovery that the geared rotary limit switch assembly was not moving with corresponding regulating blade drive mechanism movement. All immediate and subsequent actions of reactor emergency procedure REP-2, Reactor Scram, were completed. Initial investigation revealed that the upper RPI encoder sprocket, which drives the rotary limit switch slave sprocket, was not moving when its drive shaft was rotating. Further examination revealed that the two setscrews that couple the upper RPI encoder sprocket to the RPI encoder drive shaft were not tightened onto the two flat surfaces of the encoder drive shaft. The as-found positions of the setscrews indicated the setscrews were tightened against the rounded portion of the RPI encoder drive shaft, and not the flat surfaces, during recovery from LER 20-01 the previous day. The rotary shaft drive force must have overcome the setscrews friction and allowed slippage between the sprocket setscrews and the rounded portion of the shaft. After replacing the RPI encoder drive shaft, all regulating blade drive mechanism setscrews were verified to be on the drive shaft flat surfaces, had thread lock applied, and were checked tight. The Regulating Blade Operation And Rod Run-In Function Test portion of form FM-57, Long Form Startup Checksheet, was completed satisfactorily as a pre-startup final test of proper operation of the regulating blade drive mechanism and its geared rotary limit switch assembly. In accordance with TS 6.6.c, permission to restart the reactor was obtained from the Reactor Facility Director, and the reactor was returned to 10 MW operation. Failure of the regulating blade 10% withdrawn rod run-in function during reactor operation resulted in a deviation from TS 3.2.f.8, and Licensee Event Report No. 20-02 was submitted to the NRC on April 20, 2020.

Major maintenance items for the month included: completing Modification Record 18-03, Fabrication of a New Control Rod Drive Mechanism for the Regulating Rod; replacing the regulating blade drive mechanism; replacing the high-voltage power supply for nuclear instrumentation SP-1; performing a chemical cleaning of the secondary coolant side of primary coolant heat exchanger HX-503A; and performing a reactivity worth measurement in I-3

accordance with reactor physics procedure RP-RO-200, Measurement of Differential Worth of a Shim Blade, RTP-11(D).

MAY 2020 The reactor operated continuously in May with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, and one shutdown for physics measurement. There were no unscheduled/unplanned power reductions.

Major maintenance items for the month included: completing the biennial change-out of control blade B offset mechanism; performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-200, Measurement of Differential Worth of a Shim Blade, RTP-11(D); performing a chemical cleaning of the secondary coolant side of primary coolant heat exchanger HX-503B; and performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-201, Measurement of Reactivity Worth of Flux Trap Loadings or Individual Samples, RTP-17(B).

JUNE 2020 The reactor operated continuously in June with the following exceptions: five shutdowns for scheduled maintenance and/or refueling. There were no unscheduled/unplanned power reductions. An NRC inspector conducted a routine scheduled inspection of the Radiation Protection and Shipping Programs.

Major maintenance items for the month included: replacing the pool coolant demineralizer system inlet filters; performing a chemical cleaning of the secondary coolant side of pool coolant heat exchanger HX-521; placing borated shielding plugs in the thermal column beam to reduce the number of thermal neutrons interacting with air and producing argon-41; shearing radioactive waste in the reactor pool in preparation for the August 2020 Type B radioactive waste shipment; and upgrading select K-relay sockets.

JULY 2020 The reactor operated continuously in July with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, and one unscheduled/unplanned power reduction. An NRC license examiner administered one reactor operator licensing examination.

On July 7, with the reactor operating at 10 MW in the automatic control mode, an automatic reactor scram was initiated. All immediate and subsequent actions of reactor emergency procedure REP-2, Reactor Scram, were completed. Initial investigation revealed a loss of electrical power to all process instrumentation. Further troubleshooting revealed that a section of wire leading from uninterruptible power supply (UPS) distribution panel no.

2 (UPS-2) breaker no. 9 to connection point NN1 had failed. The wire was replaced, and post-maintenance testing following replacement included verifying the current reading downstream of UPS-2 breaker no. 9, and proper operation of process instrumentation. Permission to restart the reactor was obtained from the LSRO, and the reactor was returned to 10 MW operation.

Major maintenance items for the month included: replacing pneumatic tube system isolation valve PT-1; and installing underwater lighting in the reactor pool.

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AUGUST 2020 The reactor operated continuously in August with the following exceptions: five shutdowns for scheduled maintenance and/or refueling, and one unscheduled/unplanned power reduction.

On August 4, with the reactor operating at 10 MW in the manual control mode, a manual reactor scram was initiated after a Rod Not In Contact rod run-in was received due to shim control blade C anvil disengaging from its electromagnet during an outward shimming evolution. All immediate and subsequent actions of reactor emergency procedure REP-2, Reactor Scram, were completed. The control rod drive mechanism (CRDM) was removed, and the anvil was verified to be centered in the upper housing. The anvil and CRDM electromagnet were both cleaned, and nothing obvious was visually seen in the reactor pool that would have impeded the travel of the CRDM. Post-maintenance testing included two 2-inch control blade pulls. Permission to restart the reactor was obtained from the Reactor Manager, and the reactor was returned to 10 MW operation.

Major maintenance items for the month included: conducting a Type B radioactive waste shipment, which removed a significant number of items from the reactor pool and other waste storage areas in the facility; loading new de-ionizing bed G and placing it on pool coolant system service; completing Modification Record 20-01, Installation of Additional Isolation Valves to the Pneumatic Tube System; replacing nuclear instrumentation signal processor no. 2 fission chamber and cabling; completing the annual facility emergency preparedness drill; performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-200, Measurement of Differential Worth of a Shim Blade, RTP-11(D); and performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-202, Measurement of Reactivity Worth of Movable Samples, RTP-6.

SEPTEMBER 2020 The reactor operated continuously in September with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, and three shutdowns for physics measurements. There were no unscheduled/unplanned power reductions.

Major maintenance items for the month included: replacing the pool coolant demineralizer system inlet filters; replacing graphite reflector element 5A; completing Modification Record 86-01, Addendum 5, Replacement of Graphite Reflector Elements in Reflector Tank Positions 5A and 5B; performing a reactivity worth measurement in accordance with reactor test procedure RTP-5, Procedure for Regulating Blade Calibration by Positive Period Method; and performing three reactivity worth measurements in accordance with reactor physics procedure RP-RO-201, Measurement of Reactivity Worth of Flux Trap Loadings or Individual Samples, RTP-17(B).

OCTOBER 2020 The reactor operated continuously in October with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, and one unscheduled/unplanned power reduction.

On October 22, with the reactor operating at 10 MW in the automatic control mode, an automatic reactor scram was initiated due to a momentary loss of normal electrical power. All immediate and subsequent actions of reactor emergency procedures REP-2, Reactor Scram, and REP-11, Momentary Loss of Normal Electrical Power, were completed. The loss of electrical power was verified to be a fault at the University of Missouri power plant causing a power plant breaker to trip. Permission to restart the reactor was obtained from the LSRO, and the reactor was returned to 10 MW operation.

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Major maintenance items for the month included: replacing the pool coolant demineralizer system inlet filters; replacing the regulating blade offset mechanism; replacing signal wires for the pool coolant heat exchanger inlet and outlet thermocouples; and performing a reactivity worth measurement in accordance with reactor test procedure RTP-5, Procedure for Regulating Blade Calibration by Positive Period Method.

NOVEMBER 2020 The reactor operated continuously in November with the following exceptions: five shutdowns for scheduled maintenance and/or refueling. There were no unscheduled/unplanned power reductions. An NRC inspector conducted a routine scheduled inspection of Reactor Operations and Emergency Preparedness.

Major maintenance items for the month included: replacing the transmitter for primary coolant heat exchanger inlet resistance temperature detector channel TE-901B; replacing emergency pool fill valve EPF-1; completing the biennial change-out of control blade D offset mechanism; replacing the pool coolant demineralizer system inlet filters; performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-200, Measurement of Differential Worth of a Shim Blade, RTP-11(D); and completing Modification Record 72-02, Addendum 1, Drain Collection System Level Sensing and Control Upgrade-Phase 2.

DECEMBER 2020 The reactor operated continuously in December with the following exceptions: four shutdowns for scheduled maintenance and/or refueling, one shutdown for physics measurement, and two unscheduled/unplanned power reductions.

On December 7, with the reactor operating at 10 MW in the manual control mode during a reactor startup, a manual reactor shut down was performed in accordance with operating procedure OP-RO-220, Reactor Shutdown or Power Reduction, to investigate why the regulating blade auto shim switch failed to place the reactor in the automatic control mode. Corrective actions included burnishing the applicable contacts in the auto control circuit and satisfactory completion of compliance procedure CP-47, Auto Control Prohibit Channel Calibration. Permission to restart the reactor was obtained from the Reactor Manager, and the reactor was returned to 10 MW operation.

On December 24, with the reactor operating at 10 MW in the automatic control mode, a manual reactor shut down was performed in accordance with operating procedure OP-RO-220, Reactor Shutdown or Power Reduction, to investigate a significant decrease in anti-siphon system pressure. Investigation revealed that the cause of the pressure decrease was air leaking past anti-siphon system isolation valve V543B. Valve V543B was subsequently repositioned to maintain pressure. Permission to restart the reactor was obtained from the LSRO, and the reactor was returned to 10 MW operation.

Major maintenance items for the month included: performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-201, Measurement of Reactivity Worth of Flux Trap Loadings or Individual Samples, RTP-17(B); loading new de-ionizing bed W and placing it on pool coolant system service; and performing a reactivity worth measurement in accordance with reactor physics procedure RP-RO-200, Measurement of Differential Worth of a Shim Blade, RTP-11(D).

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SECTION II MURR PROCEDURES January 1, 2020 through December 31, 2020 As required by administrative MURR Technical Specification (TS) 6.6.e(5), this section of the Reactor Operations Annual Report includes a summary of procedure changes. These procedure changes were reviewed by the Reactor Manager or Reactor Health Physics Manager, as applicable, and others to assure compliance with the requirements of 10 CFR 50.59. These procedure changes were also reviewed by the Reactor Safety Procedure Review Subcommittee and/or the Isotope Use Procedure Review Subcommittee of the Reactor Advisory Committee to meet the requirements of TS 6.2.a(2).

A. CHANGES TO REACTOR OPERATIONS PROCEDURES As required by the MURR TS, the Reactor Manager reviewed the Reactor Operations procedures and found them to be adequate for the safe and reliable operation of the facility.

There were 49 revisions issued to the Reactor Operations procedures, forms, and material specification sheets.

Additionally, one new procedure and two new material specification sheets were issued, while one operator aid was obsoleted. The majority of these revisions were strictly format or editorial in nature. The following is a list of the new, revised, and obsoleted procedures, forms, material specification sheets, and operator aids:

Number Name Rev Rev Date Notes AP-RO-110 Conduct of Operations 28 03/05/20 Minor Editorial AP-RO-110 Conduct of Operations 29 08/21/20 Minor Editorial AP-RO-130 Crane Operation 10 05/01/20 Minor Editorial AP-RR-003 10 CFR 50.59 Evaluations 14 07/21/20 Minor Editorial Fingerprint-Based Criminal History Record AP-RR-008 Checks Program for Granting Unescorted Access 5 06/24/20 Minor Editorial and Access to Safeguards Information Fingerprint-Based Criminal History Record AP-RR-008 Checks Program for Granting Unescorted Access 6 10/07/20 Minor Editorial and Access to Safeguards Information AP-RR-010 Facility Access Criteria 23 06/24/20 Minor Editorial AP-RR-011 Facility Access Process 23 09/02/20 Minor Editorial AP-RR-014 On-Site Fingerprinting Program 2 07/21/20 Minor Editorial AP-RR-014 On-Site Fingerprinting Program 3 10/07/20 Minor Editorial Access Authorization Program for Irradiated AP-RR-033 4 06/24/20 Minor Editorial Reactor Fuel in Transit Access Authorization Program for Irradiated AP-RR-033 5 07/21/20 Minor Editorial Reactor Fuel in Transit Access Authorization Program for Irradiated AP-RR-033 6 10/07/20 Minor Editorial Reactor Fuel in Transit FM-15 10 CFR 50.59 Qualified Reviewers List 25 07/21/20 Minor Editorial FM-18 Deviation from Procedure Report 12 09/18/20 Minor Editorial FM-22 Containment Combination Request Form 11 06/24/20 Minor Editorial FM-43 Nuclear and Process Data Sheet 29 05/01/20 Minor Editorial II-1

Number Name Rev Rev Date Notes FM-43 Nuclear and Process Data Sheet 30 08/18/20 Minor Editorial Deviation from Facility Controlled Procedure FM-47 8 11/12/20 Minor Editorial Report FM-56 Reactor Routine Patrol 27 09/18/20 Minor Editorial FM-57 Long Form Startup Checksheet 33 08/18/20 Minor Editorial FM-57 Long Form Startup Checksheet 34 11/11/20 Minor Editorial Customer Sample Pre-Encapsulation Evaluation FM-66 10 11/11/20 Minor Editorial Worksheet Personal History Questionnaire (PHQ) and Self-FM-90 11 04/30/20 Minor Editorial Disclosure MURR Irradiations Encapsulation Evaluation FM-127 6 11/11/20 Minor Editorial Worksheet FM-140 MURR Access Inactivation Form 7 03/04/20 Minor Editorial Authorization to Conduct Background FM-200 5 03/04/20 Minor Editorial Investigation for Unescorted Access to MURR GS-RA-015 MURR Lifting and Rigging Operation 0 01/08/20 New Procedure IRR-PSO-100 Scheduling Flux Trap Tubes 11 10/07/20 Minor Editorial IRR-PSO-101 Cleaning of Sample Cans 13 03/11/20 Minor Editorial IRR-PSO-106 Target Material Control Checks 13 01/24/20 Minor Editorial Manufacturing Quartz Vials and Encapsulating IRR-PSO-109 7 10/28/20 Minor Editorial Targets in Quartz IRR-PSO-110 Target Encapsulation 15 09/18/20 Minor Editorial IRR-PSO-111 Customer Sample Pre-Encapsulation Evaluation 11 10/28/20 Minor Editorial MS-F-002 Camfil Filter Housing (180 x 168) 1 10/07/20 Minor Editorial MS-F-013 Type IV Carbon Adsorber (12x12x16) 0 10/28/20 New Document MS-F-014 I-131 Small Annular Adsorber O-Ring 0 12/10/20 New Document OA-27 Regulating Blade Drive Tower 0 07/20/20 Obsolete OP-RO-100 Main Air System 14 09/18/20 Full Review OP-RO-210 Reactor Startup - Normal 23 07/20/20 Minor Editorial OP-RO-211 Reactor Startup - Hot 19 07/20/20 Minor Editorial OP-RO-220 Reactor Shutdown or Power Reduction 14 07/29/20 Minor Editorial OP-RO-250 In-Pool Fuel Handling 23 08/18/20 Minor Editorial OP-RO-410 Primary Coolant System 18 01/24/20 Minor Editorial OP-RO-461 Pool Coolant System - One Pump Operation 19 05/01/20 Minor Editorial OP-RO-480 Secondary Coolant System 25 03/05/20 Minor Editorial OP-RO-520 Emergency Power Generator 18 10/08/20 Minor Editorial OP-RO-530 Demineralized Water Supply System 21 08/21/20 Minor Editorial OP-RO-555 Fire Protection System 18 03/05/20 Minor Editorial RM-RO-400 Waste Tank System Filter Replacement 11 06/17/20 Minor Editorial RM-RO-470 Sulfuric Acid System 16 10/29/20 Minor Editorial RP-RO-100 Fuel Movement 15 07/29/20 Minor Editorial SM-RO-011 Beryllium Reflector Replacement 8 08/03/20 Minor Editorial II-2

B. CHANGES TO EMERGENCY PLAN IMPLEMENTING PROCEDURES As required by the MURR TS, the Reactor Manager reviewed the Emergency Plan implementing procedures and found them to be adequate for the safe and reliable operation of the facility.

There were 26 revisions issued to the Emergency Plan implementing procedures, forms, and operator aids. All of these revisions were strictly format or editorial in nature. The following is a list of the revised procedures, forms, and operator aids:

Number Name Rev Rev Date Notes EP-RO-001 Definitions 6 09/30/20 Minor Editorial EP-RO-002 Emergency Responsibilities 8 03/04/20 Minor Editorial EP-RO-002 Emergency Responsibilities 9 09/30/20 Minor Editorial EP-RO-003 Emergency Preparedness Training 6 09/30/20 Minor Editorial EP-RO-004 Fire 9 09/30/20 Minor Editorial EP-RO-006 Radiological Emergency 11 09/30/20 Minor Editorial EP-RO-007 Severe Natural Phenomenon 8 09/30/20 Minor Editorial EP-RO-010 Alert 4 09/30/20 Minor Editorial EP-RO-011 Site Area Emergency 4 09/30/20 Minor Editorial EP-RO-012 Reactor Isolation 5 09/30/20 Minor Editorial EP-RO-013 Facility Evacuation 12 09/30/20 Minor Editorial Emergency Planning Zone and Site Area EP-RO-014 11 09/30/20 Minor Editorial Evacuations EP-RO-015 Emergency Notifications 20 09/30/20 Minor Editorial EP-RO-017 Emergency Air Sampling 11 09/30/20 Minor Editorial FM-104 Emergency Call List 41 03/04/20 Minor Editorial FM-104 Emergency Call List 42 09/30/20 Minor Editorial FM-105 Initial/Follow-Up Emergency Message 4 09/30/20 Minor Editorial FM-106 Log of Personnel Released from Site 4 09/30/20 Minor Editorial FM-114 Security Flowchart 4 09/30/20 Minor Editorial FM-115 Plant Conditions Flowchart 4 09/30/20 Minor Editorial FM-116 Classification Flowchart 4 09/30/20 Minor Editorial FM-117 Reactor Isolation Flowchart 4 09/30/20 Minor Editorial FM-118 Evacuation Flowchart 6 09/30/20 Minor Editorial OA-9 Combined Emergency Flowcharts 7 09/30/20 Minor Editorial OA-10 Fire Extinguisher Locations and Types 16 09/30/20 Minor Editorial OA-20 Emergency Equipment 27 09/30/20 Minor Editorial II-3

C. CHANGES TO RADIOLOGICAL CONTROL, BYPRODUCT MATERIAL SHIPPING, AND PREPARATION OF BYPRODUCT MATERIAL FOR SHIPPING PROCEDURES As required by the MURR TS, the Reactor Health Physics Manager reviewed the radiological control procedures and the procedures for the preparation for shipping and shipping of byproduct materials.

There were 76 revisions issued to the radiological control, byproduct materials shipping, and preparation for shipping byproduct material procedures, forms, material specification sheets, operator aids, and plans. Additionally, eight new procedures and one new form were issued, while 14 procedures were obsoleted. The majority of these revisions were strictly format or editorial in nature. The following is a list of the new, revised, and obsoleted procedures, forms, material specification sheets, operator aids, and plans:

Number Name Rev Rev Date Notes Pneumatic Tube Irradiation and Measurement of ACG-NAA-212 9 07/15/20 Minor Editorial High Purity Materials ACG-NAA-1725 Analyzing Platinum in Silicone 8 07/15/20 Minor Editorial AP-HP-117 MURR Initial Radiation Worker Training Program 17 12/09/20 Minor Editorial AP-HP-122 Materials License Project Review 14 10/07/20 Minor Editorial AP-HP-124 Ordering and Assigning Dosimetry 3 03/11/20 Minor Editorial AP-HP-129 Hot Cell HC-01 Control 19 10/28/20 Minor Editorial Access Authorization Program for Category 1 AP-RR-013 and/or Category 2 Quantities of Radioactive 5 07/15/20 Minor Editorial Material Access Authorization Program for Category 1 AP-RR-013 and/or Category 2 Quantities of Radioactive 6 10/08/20 Minor Editorial Material 10 CFR 21 Reporting of Defects and AP-RR-034 0 04/30/20 New Procedure Noncompliance Administrative Procedure - Radioactive Material AP-SH-001 13 07/07/20 Minor Editorial Shipping Packaging Radioactive Material for a Limited BP-SH-010 10 10/07/20 Minor Editorial Quantity Shipment Radioactive Material Shipment Package BP-SH-052 20 08/10/20 Minor Editorial Documentation and Labeling Radioactive Material Shipment Package BP-SH-052 21 10/07/20 Minor Editorial Documentation and Labeling Packaging of Type A Radioactive Material Using BP-SH-145 4 08/10/20 Minor Editorial USA DOT 7A F-458 Packaging of Type B Radioactive Material Using BPB-SH-025 6 12/03/20 Obsolete USA/0562/B(U)-96 (BEATRICE)

Packaging of Type B Radioactive Material Using BPB-SH-028 USA/9337/B(U)-96 (SAFKEG-LS) and 10 12/14/20 Minor Editorial USA/9338/B(U)-96 (SAFKEG-HS)

Receipt Inspection of New SAFKEG LS/HS Type BPB-SH-030 5 02/28/20 Minor Editorial B Byproduct Material Shipping Packages FM-26 MURR Radiation Worker Training Quiz 17 12/09/20 Minor Editorial FM-29 Dosimetry Request Packet 12 08/09/20 Minor Editorial Control Checksheet for Documentation and FM-52 22 10/07/20 Minor Editorial Labeling of Radioactive Material Shipment FM-62 Radiation Instrument Certificate of Calibration 10 05/20/20 Minor Editorial Lutetium Chloride Radiation Protection Data FM-79 13 10/07/20 Minor Editorial Sheet B II-4

Number Name Rev Rev Date Notes FM-80 Materials License Project Review Report 9 10/07/20 Minor Editorial Control Checksheet for Packaging of Type A FM-99 Radioactive Material Using USA DOT 7A MURR 13 10/28/20 Minor Editorial Model 1500 Control Checksheet for Packaging of Type A FM-99 Radioactive Material Using USA DOT 7A MURR 14 11/24/20 Minor Editorial Model 1500 Control Checksheet for Packaging Type A FM-107 13 10/07/20 Minor Editorial Radioactive Material in an Overpack FM-131 Dissolution of Gadolinium Datasheet 3 07/07/20 Minor Editorial FM-137 Type B Qualified Shipper List 30 06/10/20 Minor Editorial FM-137 Type B Qualified Shipper List 31 07/27/20 Minor Editorial FM-137 Type B Qualified Shipper List 32 12/22/20 Minor Editorial Control Checksheet for Packaging of Type A FM-145 4 08/10/20 Minor Editorial Radioactive Material Using USA DOT 7A F-458 Control Checksheet for Packaging of Type A FM-147 6 06/10/20 Minor Editorial Radioactive Material Using Tracerco LS-15 Control Checksheet for Packaging of Type A FM-147 7 08/10/20 Minor Editorial Radioactive Material Using Tracerco LS-15 Control Checksheet for Type B USA/0697/B(U)-

FM-157 12 10/07/20 Minor Editorial 96 (F-458 Series) Radioactive Material Package Control Checksheet for Health Physics Review of FM-159 13 10/07/20 Minor Editorial Radioactive Material Shipment Documentation Control Checksheet for Type B Radioactive FM-163 Material Using USA/9337/B(U)-96 (SAFKEG- 13 12/14/20 Minor Editorial LS) and USA/9338/B(U)-96 (SAFKEG-HS)

FM-165 Mo-99 Radiation Protection Data Sheet A 5 06/02/20 Minor Editorial Control Checksheet for Receipt Inspection of FM-175 4 10/07/20 Minor Editorial Customer Owned Type B Shipping Package Control Checksheet for Receipt Inspection of FM-177 4 12/14/20 Minor Editorial SAFKEG LS and HS Type B Shipping Package Control Checksheet for Documentation and FM-179 Labeling of Excepted (Limited) Quantity 4 10/07/20 Minor Editorial Radioactive Material Shipment Control Checksheet for Documentation and FM-194 Labeling of Radioactive Material Shipment 2 10/07/20 Minor Editorial Packaged in an Overpack FM-196 cMo-99 Radiation Protection Data Sheet A 0 06/02/20 New Form Control Checksheet for Receipt Inspection of FM-202 1 07/07/20 Minor Editorial SAFKEG HS Model No. 3987 Type B Inserts IC-HP-300 Calibration - Radiation Survey Instruments 10 05/20/20 Minor Editorial Mirion PING209L Stack Monitor - Flow IC-HP-306 0 10/28/20 New Procedure Calibration Calibration - Mirion PING209L Stack Monitor -

IC-HP-307 0 10/28/20 New Procedure Gas Channel Calibration - Mirion PING209L Stack Monitor IC-HP-308 0 09/18/20 New Procedure Iodine Channel Calibration - Mirion PING209L Stack Monitor IC-HP-309 0 09/28/20 New Procedure Particulate Channel Calibration - Lab Impex Smart MCA Continuous IC-HP-346 8 03/10/20 Minor Editorial Air Monitor IC-HP-353 Calibration - Lab Impex Monitor - DP2001 5 03/10/20 Minor Editorial II-5

Number Name Rev Rev Date Notes Calibration - Eberline/Thermo Model AMS-4 IC-HP-362 Continuous Air Monitor: Radial Or In-Line 4 08/09/20 Minor Editorial Sampling Head IC-HP-363 Eberline BC-4 Beta Swipe Counter - Calibration 2 08/04/20 Obsolete IC-HP-366 Eberline Model PM-7 Portal Monitor Calibration 1 10/07/20 Obsolete IC-HP-367 Calibration - I-131 Bioassay Detection System 5 05/20/20 Minor Editorial IC-HP-367 Calibration - I-131 Bioassay Detection System 6 08/09/20 Minor Editorial Calibration - Hi-Q Portable Air Sampler - Model IC-HP-370 0 08/04/20 Obsolete CF-993B MS-B-057 Keg Closure Nut for SAFKEG HS Model 3977A 4 12/14/20 Minor Editorial MS-B-064 Keg Closure Stud for SAFKEG HS Model 3977A 5 11/10/20 Minor Editorial MS-B-069 Loctite 270 or Loctite 263 3 06/10/20 Minor Editorial Control Checksheet for Changing P-Tube Pre-OA-25 4 11/11/20 Minor Editorial Filters NRC 749 Manual License Verification Report for OA-26 3 11/10/20 Minor Editorial Category 2 Materials OP-HP-220 Tritium Bioassay 13 08/09/20 Minor Editorial OP-HP-228 Performing Iodine 131 Bioassay Measurements 8 10/07/20 Minor Editorial OP-HP-236 Respirator Selection, Issuance, and Wearing 4 05/20/20 Minor Editorial OP-HP-300 Receipt of Radioactive Material 13 06/18/20 Minor Editorial OP-HP-306 Health Physics Daily Facility Checks 12 06/18/20 Minor Editorial OP-HP-350 Eberline Model PING 1A - Filter Change 10 07/07/20 Minor Editorial Operation of the Hot Cell (HC-09) Interim Storage OP-HP-500 4 10/07/20 Minor Editorial Silo Preparing and Submitting a Radioactive Sample PRC-RRD-001 8 01/08/20 Minor Editorial for Packaging PRC-RRD-103 Remote Quartz Vial Washing 7 03/11/20 Minor Editorial PRC-RRD-106 Separation of Dy/Ho 166 3 10/08/20 Obsolete PRC-RRD-214 LN1 Carrier-Free Lu-177 Process 8 10/08/20 Obsolete PRC-RRD-217 Dissolving Lu-177 5 06/18/20 Minor Editorial PRC-RRD-218 Lu-177 Distribution 11 06/18/20 Minor Editorial PRC-RRD-312 Gum Arabic Formation of Au Nanoparticles 2 10/15/20 Obsolete PRC-RRD-313 Au Dissolution 8 06/18/20 Minor Editorial PRC-RRD-317 Ce-Oxide Dissolution 3 10/08/20 Obsolete PRC-RRD-318 Dissolution of Copper Nitrate 3 10/08/20 Obsolete PRC-RRD-319 Cd-115/In-115m Processing 2 10/08/20 Obsolete PRC-RRD-414 Dissolution of Gadolinium Nitrate 8 07/07/20 Minor Editorial PRC-RRD-421 Dissolving Re-186 8 01/08/20 Minor Editorial PRC-RRD-422 Preparing 153Sm EDTMP From Lyophilized Kits 2 10/08/20 Obsolete PRC-RRD-423 Quality Control Testing of 153Sm EDTMP 4 10/08/20 Obsolete Sodium Iodide Spectral Qualitative Analysis for QA-SH-002 Excepted, Type A, and Type B Radioactive 10 10/07/20 Obsolete Material Shipments QA-SH-003 Release of NorthStar Mo-99 Product Vessels 0 10/07/20 Obsolete QAB-SH-002 Procurement of Type B Packages 8 05/28/20 Minor Editorial QAB-SH-003 Material Control for Type B Shipping Program 10 07/07/20 Minor Editorial Training for Type B Shipment Leak Test QAB-SH-008 5 02/28/20 Minor Editorial Performers II-6

Number Name Rev Rev Date Notes Procurement of Parts and Services for Type B QAB-SH-010 0 05/28/20 New Procedure Packages RCP-PSO-020 Selenium-75 Process 4 10/28/20 Full Review RCP-PSO-025 Selenium-75 Distribution 0 08/09/20 New Procedure RP-HP-135 Room 114 Entry - Self Monitored 11 06/18/20 Minor Editorial SV-HP-119 Property Release 14 06/18/20 Minor Editorial Building Exhaust Stack Effluent - Ar-41 SV-HP-121 10 05/20/20 Minor Editorial Monitoring TSP-02 Transportation Security Plan 11 11/16/20 Minor Editorial WM-SH-105 Radioactive Waste Processing 15 07/07/20 Minor Editorial WM-SH-115 Iodine I-131 Waste Handling 6 02/28/20 Minor Editorial WM-SH-115 Iodine I-131 Waste Handling 7 11/24/20 Minor Editorial Removal of Waste from Hot Cell HC-11A Using WM-SH-116 0 01/24/20 New Procedure Shielded Container II-7

SECTION III REVISIONS TO THE SAFETY ANALYSIS REPORT January 1, 2020 through December 31, 2020 On August 31, 2006, MURR submitted a request to the NRC to renew Amended Facility Operating License No. R-103 for another twenty years of operation, at which time MURR also provided its proposed Safety Analysis Report (SAR). On January 4, 2017, the NRC issued Renewed Facility Operating License No. R-103.

From 2017 through 2020, a significant amount of effort was spent by MURR staff to update the August 31, 2006, SAR with all of the facility changes and modifications that had occurred between 2006 and 2017, and with applicable information from the hundreds of MURR responses to NRC Requests for Additional Information during the relicensing process.

During calendar year 2020, modifications or changes to the facility occurred that required the following revisions to the SAR, as submitted to the NRC in 2006 for relicensing. The following changes have been reviewed, in accordance with 10 CFR 50.59, by licensed staff and members of the Reactor Safety Subcommittee; determined not to involve a change to the MURR Technical Specifications; and approved by the Reactor Manager.

CHAPTER 7 - INSTRUMENTATION AND CONTROL Section 7.3.1, Figure 7.4 (pages 7-17/18)

Update with Print No. 138, Sheet 1 of 1, Annunciator Control 10 MW., Rev. 53 dated 06/24/20 Section 7.6.2.2, Figure 7.7 (pages 7-39/40) (as revised by the 2019 Reactor Operations Annual Report)

Update with Print No. 41, Sheet 2 of 4, 10MW Process Instrumentation Control & Interlock (Temperature Inst.),

Rev. 29 dated 06/24/20 CHAPTER 10 - EXPERIMENTAL FACILITIES AND UTILIZATION Section 10.3.4.2, last paragraph (page 10-17)

Add statements to read: The p-tube system also has isolation valves that can be closed to prevent the continuous flow of air and subsequent 41Ar production from the system. Isolation of the system can only be performed after all p-tube irradiations are complete, and the system is not required. The isolation valves are administratively controlled and will normally only be re-opened after the reactor is shut down and sufficient decay time has elapsed for the removal of 41 Ar.

CHAPTER 11 - RADIATION PROTECTION PROGRAM AND WASTE MANAGEMENT Section 11.1.1.1.1, Table 11-1, first row, last column (page 11-3)

Revise to read: 3.72 x 10-4 1.46 x 10-3a III-1

Section 11.1.1.1.1, Table 11-1 (page 11-3)

Add beneath table to read: a Does not account for additional 41Ar reduction when part of the system is isolated.

Section 11.1.5.2, last bullet (pages 11-50/51)

Add statements to read: Additionally, isolation valves in the system can be closed and the system made unavailable to prevent continuous air flow and the subsequent thermal neutron interaction with additional 40Ar. The isolation valves are administratively controlled and will normally only be reopened after the reactor is shut down and sufficient decay time has elapsed for the removal of 41Ar.

III-2

SECTION IV PLANT AND SYSTEM MODIFICATIONS January 1, 2020 through December 31, 2020 For each facility modification described below, MURR has on file the safety screen or evaluation, as well as the documentation of review, performed pursuant to 10 CFR 50.59.

MODIFICATION RECORD 19-01, ADDENDUM 1 Replacement of Regeneration System with Resin Handling System This addendum to Modification Record 19-01, Replacement of Primary and Pool Coolant System Demineralizer Tanks, documents the removal of the resin regeneration system and installation of a new resin handling system consisting of two 150-gallon poly tanks for dumping and drying resin, as well as an educator to load new resin. This system is plumbed to allow spent resin to be dumped directly from the storage tank or resin columns to the poly tanks and educt new resin directly into the resin columns or storage tank. New supply lines for compressed air, facility demineralized water, and liquid radioactive drains have been installed to support this modification.

MODIFICATION RECORD 01-04, ADDENDUM 13 Addition of a Single Point Calibration Reference to the Reactor Inlet and Outlet Temperature Channels (TE 901A/B) and to the Pool Coolant Heat Exchanger Inlet and Outlet Temperature Channels (TE 901C/D)

This addendum to Modification Record 01-04, Replacement of the General Electric Measurement and Control (GE/MAC) Process Instrumentation MV/I Transmitters, Differential Temperature Summers, Square Root Converters, and Dual Alarm Units, documents the addition of toggle switches to both the reactor and pool coolant heat exchanger inlet and outlet temperature channels. Resistance temperature detector (RTD) instrument channels TE-901A and TE-901B share one toggle switch, while TE-901C and TE-901D share another. Both switches can be placed in either the OPERATE or TEST position. The TEST position is used to response check the RTD transmitter and provide indication of proper operation and calibration prior to reactor startup.

MODIFICATION RECORD 18-03 Fabrication of a New Control Rod Drive Mechanism for the Regulating Rod This modification record documents the new design and installation of a control rod drive mechanism for the regulating rod - referred to as the regulating rod (blade) drive mechanism (RRDM). Prior to installation of the new RRDM, the previous RRDM had been in operation for nearly 54 years and, since 1974, there have been 25 licensee event reports submitted to the NRC that have been attributed to various failures of the RRDM during reactor operation.

In addition to not having a direct replacement RRDM available, various control functions on the RRDM were extremely antiquated, such as the drive chains and geared rotary limit switches, with much more robust, dependable and newer technology replacement parts now available that should significantly increase the reliability of the RRDM.

Therefore, instead of fabricating a new RRDM as currently designed, certain RRDM functions have been redesigned using these newer technology replacement parts. A second RRDM has been fabricated as an available spare.

IV-1

MODIFICATION RECORD 20-01 Installation of Additional Isolation Valves to the Pneumatic Tube System This modification record documents the installation of additional isolation valves just above the pneumatic tube (p-tube) solenoid cabinet - one in each of the lines leading to and from Labs 216 and 218, and in each of the lines leading to and from the active p-tube irradiation positions. Prior to installation of these isolation valves, the p-tube system, even when secured, provided a continuous flow path for air in order to prevent the accumulation of Ar-41 in the termini and subsequent significant release when the system is started while the reactor is in operation. As a result, the system design resulted in the largest production term for Ar-41 due to the high volume of air that is irradiated by a high neutron flux at the tubes termini, which are located in the graphite reflector region, whether the system was or was not in operation. Now, when air flow through the p-tube system is secured, the new isolation valves are closed, which prevent air from flowing through the system, thus reducing the amount of Ar-41 released through the exhaust stack during reactor operation. Re-opening of the isolation valves is a planned activity, normally performed after the reactor is shut down and appropriate decay time has been achieved.

MODIFICATION RECORD 86-01, ADDENDUM 5 Replacement of Graphite Reflector Elements in Reflector Tank Positions 5A and 5B This addendum to Modification Record 86-01, Reflector Graphite Element 5A and 5B Replacement, documents the replacement of the two reflector elements in positions 5A and 5B with reflector elements configured to better meet the future needs of MURR customers. These replacement elements are constructed each with three 1-inch diameter sample irradiation positions located along the inner radius of the element, closest to the reactor core. This configuration maximizes the neutron flux available to the samples.

MODIFICATION RECORD 72-02, ADDENDUM 1 DCS Level Sensing & Control Upgrade-Phase 2 This addendum to Modification Record 72-02, Primary/Pool Drain Collection System, documents enhancements to the drain collection system (DCS) and its control panel. As originally designed, the DCS and its control panel serve to collect and re-use tritiated water from pool and primary coolant systems sources and as a means for the movement of pool water via gravity drain and manual pumping between the pool coolant system and demineralized storage tank T-301. From a functionality standpoint, the system remains the same. Control of the system is now provided by a programmable logic controller (PLC) unit mounted on the reactor control room instrument panel with additional interlocks added for system safety and configuration control. Operation of DCS pump P-536 is now driven by the position of DCS pump discharge valve 565A. This is a system protective feature to prevent operation of the pump without the discharge valve open. Configuration control interlocks have been added to the operation of valves 565B, 515H, and 524. Inadvertent operation of these valves could result in an unintended change in reactor pool level. To prevent this, a two-second time delay has been added to each of their switches on the updated PLC. Lastly, the power supply for the DCS panel will be transferred from uninterruptible power supply (UPS) distribution panel no. 2 (UPS-

2) breaker no. 9 to LP-21 breaker no. 36 to reduce the loading on the UPS panels by removing non-safety systems wherever possible.

IV-2

MODIFICATION REDORDS 12-01 & 19 LETTER TO FILE (February 12, 2020)

Addition of Fuses to Supply Side of Process Instrument Low Voltage Power Supplies (LVPS) 2PS4 and 2PS7 This letter to Modification Record 12-01, Replace PT-944A/B with Rosemount Transmitters, and Modification Record 19-05, Replacement of DPS-930 Transmitter and Indication, documents the addition of fuses to the supply side of 2PS4 and 2PS7, which were the two remaining LVPS with no method of securing power to them without opening the main supply breaker at the UPS panel. The fuses provide additional overcurrent protection and another means of securing power as an alternative to securing power at the UPS breaker.

MODIFICATION RECORD 14-01, ADDENDUM 1 - LETTER TO FILE (April 21, 2020)

HC-11 Light Fixture Replacement This letter to Modification Record 14-01, Addendum 1, Construction of Usable Laboratory Spaces within the Expanded MURR Industrial Building, documents the replacement of light fixtures within hot cell HC-11 for better illumination of the working space.

MODIFICATION RECORD 01 LETTER TO FILE (June 4, 2020)

Upgrading Relay Sockets for Eight (8) K Relays This letter to Modification Record 01-11, Replace K Relay Sockets with an Improved Design, documents the replacement of eight additional relay sockets to the same enhanced design as those replaced in 2002. The relay positions replaced were K1-K6, K11, and K15. The enhanced relay sockets perform their function in the same manner as those previously installed but will better facilitate removal and replacement during compliance procedures.

MODIFICATION RECORD 18 LETTER TO FILE (August 14, 2020)

Replacement of CRDM Magnet Lead This letter to Modification Record 18-02, Fabrication of a New Control Rod Drive Mechanism, documents the replacement of the control rod drive mechanism (CRDM) electromagnet lead with a smaller diameter version. The original version of this coiled lead has demonstrated some issues with bunching up inside the guide tube and causing the electromagnet to tilt, ultimately resulting in the electromagnet disengaging from the anvil. The primary benefit of the new lead was the reduced thickness and coil diameter which prevented the bunching issue experienced with the previous lead. However, this new, thinner lead failed bench testing because it would pinch in the gap between the guide tube and electromagnet.

MODIFICATION RECORD 18 LETTER TO FILE (August 14, 2020)

Addition of Adjustment Slot in Regulating Blade Drive Mechanism Motor This letter to Modification Record 18-03, Fabrication of a New Control Rod Drive Mechanism for the Regulating Rod, documents the addition of an adjustment slot in the motor of the RRDM, which allows manual movement of the motor. This is needed to make fine adjustments to the RRDM position when coupling the RRDM to the regulating blade pull rod. The original RRDM design had exposed gears and chains, which could be manually turned to position IV-3

the RRDM up and down to mate up with the drive tube. The new design does not have any exposed rotational parts for manual adjustments. The motor end-cover now has a hole drilled through the center, and the motor shaft end, which extends out approximately 1/2-inch, has a slot cut through its center.

MODIFICATION RECORD 88 LETTER TO FILE (September 7, 2020)

Modifications to the Emergency Power Generator Remote Alarm Panel This letter to Modification Record 88-06, Emergency Electrical Power Upgrade (Replacing Emergency Generator and Automatic Transfer Switch), documents the replacement of the emergency power generator alarm panel. The new panel face removed the non-functional alarm lamps that were not operational with original installation and alarms obsoleted by Modification Record 88-06, Addendum 2.

MODIFICATION RECORD 19 LETTER TO FILE (October 7, 2020)

Room 111 Demolition This letter to Modification Record 19-02, Modification to the Laboratory Building Configuration, documents the demolition of Rooms 111 and 111A in the basement of the laboratory building. The walls to Rooms 111 and 111A were demolished, thus allowing this space to become part of the overall basement area, which frees it up for future use. The scope of this letter includes removal of evacuation and paging, fire protection, electrical, compressed air, domestic cold water, and radioactive exhaust services to the room.

MODIFICATION RECORD 18 LETTER TO FILE (October 9, 2020)

CRDM Enhancements Identified During Refurbishment This letter to Modification Record 18-02, Fabrication of a New Control Rod Drive Mechanism, documents additional enhancements to the CRDMs as they are being systematically refurbished. These enhancements include an updated ball nut; updated CRDM electromagnet lead of a different design than described in the letter to file dated August 14; the addition of polytetrafluoroethylene bushings according to the original prints; and mounting points for the wiring harness.

MODIFICATION RECORD 90-01, ADDENDUM 1 - LETTER TO FILE (October 21, 2020)

Removal of One (1) Evacuation Strobe Light in Room 111 This letter to Modification Record 90-01, Evac Horn, documents the removal of the evacuation strobe from Room 111. Room 111 was demolished and no longer required this strobe.

MODIFICATION RECORD 85 LETTER TO FILE (October 22, 2020)

Regulating Blade As Built Updates This letter to Modification Record 85-08, Reg Rod Offset, documents the as-built print updates for the new regulating blade offset mechanism, which was installed in fall 2020.

IV-4

MODIFICATION RECORD 14-01, ADDENDUM 1 - LETTER TO FILE (November 9, 2020)

HC-11A/B/C In-Cell Filter Replacements This letter to Modification Record 14-01, Addendum 1, Construction of Usable Laboratory Spaces within the Expanded MURR Industrial Building, documents the replacement of hot cell HC-11A/B/C in-cell ventilation exhaust filters with various filters other than the original stainless-steel housing filters loaded with charcoal. More importantly, this letter documents that MURR is not considering any HC-11 in-cell filter meeting the requirements of Technical Specification 3.10.d.

IV-5

SECTION V NEW TESTS AND EXPERIMENTS January 1, 2020 through December 31, 2020 The following new and amended tests or experiments were approved during calendar year 2020 under a Reactor Utilization Request (RUR):

RUR 458 Molybdenum Metal in Zircaloy Encapsulation This RUR authorizes the irradiation of up to 365 grams of natural molybdenum metal in the graphite reflector region of the reactor for use in medical diagnostic applications.

RUR 425, AS AMENDED Enriched Gadolinium Nitrate This RUR amendment authorizes the decrease in the gadolinium target mass from 5.0 mg to 2.0 mg and stipulated an increase in Gd-160 enrichment to greater than 98%.

In addition, MURR continued to participate in molybdenum-99 research and development, and production activities by performing test and production irradiations and target processing using various methodologies. The majority of the 2020 research and development efforts were focused on improving the efficiency of molybdenum production using enriched molybdenum targets instead of natural molybdenum targets.

Each of these tests or experiments has a written safety evaluation on file and a 10 CFR 50.59 Screen, if applicable, to assure that the test or experiment is safe and within the limits of MURR Technical Specifications. The safety evaluations have been reviewed by the Reactor Manager, Reactor Health Physics Manager, Assistant Reactor Manager-Physics, and the Reactor Safety Subcommittee, as applicable.

V-1

SECTION VI SPECIAL NUCLEAR MATERIAL AND REACTOR PHYSICS ACTIVITIES January 1, 2020 through December 31, 2020 INSPECTIONS The NRC conducted one routine inspection reviewing special nuclear material (SNM) activities during calendar year 2020. All records and activities were found to be in compliance with NRC rules and regulations. No violations were noted.

REACTOR CHARACTERISTICS MEASUREMENTS Fifty-eight refueling evolutions were completed in 2020. Reactor core excess reactivity verifications were performed for each refueling. The largest measured excess reactivity was 3.89%. MURR Technical Specification (TS) 3.1.a requires reactor core excess reactivity above reference core condition to be less than 9.8%.

REACTIVITY MEASUREMENTS Differential blade-worth measurements of six shim control blades were performed either following a planned replacement of a control blade or to ensure compliance with TS 4.2.g.

Two differential blade-worth measurements of the regulating blade were performed. One measurement was taken before and one measurement was taken after a planned replacement of the regulating blade and its associated offset mechanism.

Two reactivity measurements were performed to estimate the change in core total reactivity due to the sequential replacement of two graphite reflector elements that contained a significant amount of thermal neutron-absorbing material with two graphite reflector elements that do not significantly absorb thermal neutrons.

Four reactivity measurements were performed to estimate the total reactivity worth of the center test hole removable experiment sample canister, in addition to all samples loaded in the center test hole region of the reactor.

One reactivity measurement was performed to estimate the worth of a small diameter center test hole sample holder loaded with a mixture of samples.

One reactivity measurement was performed to estimate the worth of a large diameter center test hole sample containing an enriched molybdenum target.

VI-1

SECTION VII RADIOACTIVE EFFLUENT January 1, 2020 through December 31, 2020 TABLE 1 SANITARY SEWER EFFLUENT Descending Order of Activity Released for Nuclide Totals > 1.000E-02 mCi Nuclide Activity (mCi)

H-3 1.49E+02 S-35 6.96E+00 Co-60 5.98E+00 Lu-177 4.94E+00 Zn-65 1.97E+00 In-115m 4.08E-01 Cr-51 3.71E-01 Sc-46 2.73E-01 Fe-59 2.66E-01 Lu-177m 2.36E-01 Cd-115 1.45E-01 Tc-99m 9.18E-02 Ca-45 5.92E-02 Na-24 5.12E-02 Re-186 5.09E-02 Mo-99 4.53E-02 Be-7 4.10E-02 Mn-54 2.44E-02 Co-58 1.52E-02 Total H-3 1.49E+02 Total Other 2.19E+01 Sanitary sewer effluents are in compliance with 10 CFR 20.2003, Disposal by Release into Sanitary Sewerage.

VII-1

TABLE 2 STACK EFFLUENT Ordered by % Technical Specification Limit Average Concentration Total Release Isotope TS Limit Multiplier  % TS

(µCi/ml) (µCi)

Ar-41 2.64E-06 1.23E+09 350 75.4580 I-131 3.50E-12 1.63E+03 1 1.7517 C-14* 2.40E-11 1.12E+04 1 0.8000 Xe-131m 4.15E-07 1.93E+08 350 0.0592 H-3 2.03E-08 9.47E+06 350 0.0581 Os-191 3.99E-14 1.86E+01 1 0.0020 Hg-203 5.99E-15 2.79E+00 1 0.0006 Br-82 2.57E-12 1.20E+03 350 0.0001 C-14 activity is calculated based on the ratio of argon to nitrogen in the air and the (n, p) reaction cross sections for the activation of N-14 to C-14.

Isotopes observed at < 0.0001% Technical Specification (TS) limit are not listed.

Stack Flow Rate = ~30,000 cfm Stack effluent releases are in compliance with University of Missouri-Columbia Research Reactor, Renewed Facility Operating License No. R-103 TS.

VII-2

SECTION VIII ENVIRONMENTAL MONITORING AND HEALTH PHYSICS SURVEYS January 1, 2020 through December 31, 2020 Environmental samples are collected two times per year at eight locations and analyzed for radioactivity. Soil and vegetation samples are also taken at each location. Water samples are taken at three locations while subsurface soil samples are taken at six locations each period. Analytical results are shown in Tables 1 and 2.

Table 3 lists the radiation doses recorded by the environmental monitors deployed around MURR in 2020. All doses fluctuate around background except monitor numbers 4, 8, and 9. These monitors are located near a loading dock area where packages containing radioactive material are loaded or traversed prior to being placed on transport vehicles.

The doses recorded by these monitors are considered to be the result of exposure to packages in transit. The environmental monitoring program confirms that minimal environmental impact exists from the operation of the MURR facility.

The number of radiation and contamination surveys performed each month is provided in Table 4.

TABLE 1

SUMMARY

OF ENVIRONMENTAL SET 97 - SPRING 2020 Detection Limits*

Matrix Alpha I Beta I Gamma Tritium Vegetation 0.43 pCi/g 7.12 pCi/g 1.15 pCi/g 5.96 pCi/mL Soil 0.68 pCi/g 3.36 pCi/g 0.52 pCi/g N/A Water 0.00 pCi/g 2.54 pCi/g 174.80 pCi/L 6.48 pCi/mL Subsurface Soil 0.00 pCi/g 2.47 pCi/g 0.48 pCi/g N/A Activity Levels - Vegetation Alpha Beta Gamma Tritium Sample (pCi/g) I (pCi/g) I (pCi/g) (pCi/mL) 1V97 <MDA 34.72 <MDA <MDA 2V97 <MDA 37.21 <MDA <MDA 3V97 <MDA 25.10 <MDA <MDA 4V97 <MDA 33.65 <MDA <MDA 5V97 <MDA 28.31 <MDA <MDA 6V97 <MDA 62.49 <MDA <MDA 7V97 <MDA 40.42 <MDA <MDA 10V97 <MDA 38.99 <MDA <MDA VIII-1

TABLE 1 (Contd)

SUMMARY

OF ENVIRONMENTAL SET 97 - SPRING 2020 Activity Levels - Soil Alpha Beta Gamma Sample (pCi/g) (pCi/g) (pCi/g) 1S97 1.18 21.81 3.39 2S97 0.74 22.88 4.28 3S97 0.88 19.67 2.77 4S97 <MDA 24.30 3.97 5S97 <MDA 25.91 3.97 6S97 1.18 13.62 2.51 7S97 <MDA 12.55 2.96 10S97 <MDA 18.07 4.46 Activity Levels - Water Alpha Beta Gamma Tritium Sample (pCi/g) (pCi/g) (pCi/g) (pCi/mL) 4W97 0.17 6.71 200.65 <MDA 6W97 0.64 7.72 <MDA <MDA 10W97 0.08 12.67 <MDA <MDA Activity Levels - Subsurface Soil Alpha Beta Gamma Sample (pCi/g) (pCi/g) (pCi/g)

E97 1.04 23.94 4.19 S97 1.04 22.88 3.86 SW97 1.48 22.17 4.35 W97 0.74 23.23 3.95 N97 1.19 24.65 4.18 NE97 0.44 27.84 3.91 Gamma and tritium analyses are based on wet weights while alpha and beta are based on dry weights. HPGe spectral analyses were performed on any sample with a gamma activity greater than minimum detectable activity (MDA).

VIII-2

TABLE 2

SUMMARY

OF ENVIRONMENTAL SET 98 - FALL 2020 Detection Limits*

Matrix Alpha Beta Gamma Tritium Vegetation 1.38 pCi/g 16.40 pCi/g 1.20 pCi/g 6.65 pCi/ml Soil 0.69 pCi/g 7.85 pCi/g 0.53 pCi/g N/A Water 0.99 pCi/g 10.68 pCi/g 180.49 pCi/L 6.44 pCi/ml Subsurface Soil 0.38 pCi/g 2.36 pCi/g 0.56 pCi/g N/A Activity Levels - Vegetation Alpha Beta Gamma Tritium Sample (pCi/g) (pCi/g) (pCi/g) (pCi/mL) 1V98 <MDA 53.19 1.45 <MDA 2V98 <MDA 20.62 <MDA <MDA 3V98 <MDA <MDA <MDA <MDA 4V98 <MDA 39.44 <MDA <MDA 5V98 <MDA 30.75 <MDA <MDA 6V98 <MDA 24.96 <MDA <MDA 7V98 <MDA 23.16 <MDA <MDA 10V98 <MDA 27.86 <MDA <MDA Activity Levels - Soil Alpha Beta Gamma Sample (pCi/g) (pCi/g) (pCi/g) 1S98 <MDA 20.44 2.61 2S98 <MDA 20.80 2.86 3S98 <MDA 17.19 2.57 4S98 1.19 19.72 3.33 5S98 1.04 18.99 3.20 6S98 <MDA 15.20 3.27 7S98 <MDA 21.89 2.91 10S98 <MDA 22.97 3.64 VIII-3

TABLE 2 (Contd)

SUMMARY

OF ENVIRONMENTAL SET 98 - FALL 2020 Activity Levels - Water Alpha Beta Gamma Tritium Sample (pCi/g) (pCi/g) (pCi/g) (pCi/mL) 4W98 <MDA <MDA <MDA <MDA 6W98 <MDA 17.25 <MDA <MDA 10W98 <MDA <MDA <MDA <MDA Activity Levels - Subsurface Soil Alpha Beta Gamma Sample (pCi/g) (pCi/g) (pCi/g)

E98 <MDA 22.43 5.32 S98 0.74 25.57 4.74 SW98 <MDA 24.09 4.85 W98 <MDA 23.72 4.46 N98 1.78 21.88 4.31 NE98 <MDA 22.06 4.71 Gamma and tritium analyses are based on wet weights while alpha and beta are based on dry weights. HPGe spectral analyses were performed on any sample with a gamma activity greater than MDA.

VIII-4

TABLE 3 ENVIRONMENTAL TLD

SUMMARY

Badge Direction from Meters from 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter Total Number MURR MURR Stack (net mrem) (net mrem) (net mrem) (net mrem) (net mrem) 0* Control N/A 38 36 25 35 134 1* Control N/A 36 32 26 26 120 2* Control N/A 38 34 24 32 128 3 W 30 -5 -3 -4 -4 -16 4 SW 59 30 17 18 11 76 5 ENE 110 -6 -7 -9 -2 -24 6 NNE 84 0 -1 0 5 4 7 ENE 55 -3 -3 -3 -2 -11 8 SW 32 11 21 15 35 82 9 SSE 27 22 20 11 23 76 10 NE 139 -6 -7 -3 -5 -21 11 N 135 -8 -8 -7 -5 -28 12 NE 284 -2 -1 1 3 1 13 NNE 305 -7 -6 -3 -6 -22 14 S 168 -4 -3 -4 0 -11 15 SSE 74 -5 -4 -4 -3 -16 16 SE 113 -4 -7 -5 -1 -17 17 E 299 -8 -10 -5 -6 -29 18 NE 453 -9 -6 -5 -4 -24 19 NE 673 -10 -11 -9 -8 -38 20 NE 893 -12 -11 -8 -10 -41 21 SSE 239 -2 -5 -1 0 -8 22 SE 158 -10 -10 -9 -9 -38 23 NW 89 0 -1 -1 3 1 24 SSW 308 -4 -4 -2 0 -10 25 SSW 435 -9 -3 -1 -1 -14 26 SSW 365 -8 -6 -4 -2 -20 27 SW 170 -11 -10 -9 -5 -35 28 NW 229 -3 -5 -3 1 -10 29 NW 260 -6 -3 -4 -2 -15 30 N 335 -9 -10 -7 -7 -33 31 NNE 677 -4 -4 -4 1 -11 32 NW 760 -4 -1 -1 1 -5 33 ESE 578 -10 -9 -7 -9 -35 34 ENE 596 -10 -12 -9 -9 -40 35 SSE 477 Missing 0 -18 Missing -18 36 SE 446 -7 -5 -2 -4 -18 37 NE 732 -11 -11 -7 -10 -39 38 NW 487 -2 -3 0 -1 -6 39 W 528 -6 -5 -3 -4 -18 40 N 503 -7 -10 -5 -4 -26 41 NE 161 -8 -6 -5 -6 -25 42 In Building N/A 5 5 6 6 22 43 In Building N/A -3 -1 -1 0 -5 44 SW 102 -1 -5 -4 -2 -12 45 SE 94 -1 1 -4 9 5 46 SE 105 -3 -2 1 1 -3 The control monitors are approximately 50 miles SE of MURR, and gross values are shown.

VIII-5

TABLE 4 NUMBER OF FACILITY RADIATION AND CONTAMINATION SURVEYS Receipt of Surface Radiation Month Radiation Air Samples** Radioactive Contamination* Work Permits Materials January 102 102 37 16 9 February 109 109 33 13 7 March 92 92 28 8 6 April 71 71 2 13 4 May 109 109 36 15 1 June 120 120 39 19 3 July 95 95 43 22 2 August 94 94 31 21 3 September 105 105 41 20 2 October 108 108 40 16 7 November 102 102 34 15 1 December 103 103 35 13 1 TOTAL 1,210 1,210 399 191 46 In addition, general building contamination surveys are conducted each normal working day.

Air samples include stack Ar-41, containment Ar-41, sump entries, and hot cell entries.

Miscellaneous Note During calendar year 2020, MURR shipped 1,788 cubic feet of low-level radioactive waste containing 183,523 mCi of activity. The increase in activity compared to previous years is representative of removing waste stored in areas in the facility and the reactor pool. This radioactive waste shipment contained an additional 36 cubic feet and 113,950 mCi.

VIII-6

SECTION IX

SUMMARY

OF RADIATION EXPOSURE TO FACILITY STAFF, EXPERIMENTERS, AND VISITORS January 1, 2020 through December 31, 2020 Total Personnel Dose (mrem) by Dosimetry Group AC/PRD BCS DO FOE HC HP IRR NA NS NSP OPS QA RES RP SH SIL TEE WC Total January 111 3 2 108 301 285 0 12 54 78 1248 72 41 16 25 70 22 0 2,448 February 120 1 5 91 99 97 0 4 17 114 784 32 19 19 28 25 12 0 1,467 March 129 0 0 96 198 177 0 0 14 146 1351 78 48 18 53 9 2 4 2,323 April 167 0 1 103 126 304 0 6 26 122 713 100 91 7 32 11 7 0 1,816 May 259 7 0 90 128 406 7 4 30 460 842 61 12 24 139 22 16 TR 2,507 June 246 7 0 223 168 417 1 73 132 129 1480 121 55 61 61 0 5 TR 3,179 July 95 1 7 40 97 477 0 68 48 80 1500 94 25 12 17 OB 0 TR 2,561 August 43 0 1 2 23 33 0 0 0 6 179 25 4 6 16 OB 3 TR 341 September 223 4 3 85 162 335 0 6 53 111 1068 99 49 21 35 OB 22 TR 2,276 October 161 15 17 90 118 204 4 27 73 242 1010 84 51 38 47 OB 16 TR 2,197 November 169 8 46 209 131 156 0 1 56 106 1025 43 32 2 41 OB 2 TR 2,027 December 172 30 6 16 104 400 6 50 11 102 869 20 7 13 26 OB 25 TR 1,857 IX-1 Total for Year 1,895 76 88 1,153 1,655 3,291 18 251 514 1,696 12,069 829 434 237 520 137 132 4 24,999 Monthly Average 158 6 7 96 138 274 2 21 43 141 1,006 69 36 20 43 11 11 0 2,083 Highest WB 338 112 17 215 448 894 11 16 182 318 731 180 143 82 98 99 39 4 (annual)

High Extremity 5,567 267 NM 222 1,538 1,888 46 295 21 3,401 1,893 6,914 2,887 354 978 86 43 0 (annual)

AC/PRD-Analytical Chemistry/Production HP-Health Physics OPS-Operations SH-Shipping BCS-Business & Central Services IRR-Irradiations QA-Quality Assurance SIL-Silicon DO-Director's Office NA-Neutron Activation RES-Research TEE-Trace Elemental Epidemiology FOE-Shops & Support NS-Neutron Scattering RP-Radiopharmaceutical WC-Work Control HC-Hot Cell NSP-NorthStar Partners WB-Whole Body NM-Not Monitored OB-Obsolete TR-Transfer to New Group Analysis of personnel exposure levels indicates that exposures are significantly below the limits of 10 CFR 20.1201 and are generally maintained ALARA.

No significant personnel exposures occurred during this monitoring year.

WC and SIL group members were removed or moved into different groups and will not be reported as groups going forward.

Dosimetry services are provided by Mirion Technologies (except self-reading dosimetry).

Due to the COVID-19 pandemic, dosimetry services scheduling experienced interruptions from January through August. This caused dosimetry wear periods to be uneven from month-to-month. For example, August 2020 dosimeters were only issued to personnel for eight days making August dose appear extremely low. The scheduling services were consistent again starting in September.