ML21228A132

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2021 Annual Report for the Wsu Nuclear Science Center
ML21228A132
Person / Time
Site: Washington State University
Issue date: 08/16/2021
From: Hines C
Washington State Univ
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML21228A132 (16)


Text

August 16, 2021 Document Control Desk U.S. Nuclear Regulatory Commission Washington DC, 20555

Reference:

Washington State University Modified TRIGA Reactor License No. R-76; Docket No.50-027

Subject:

2021 Annual Report for the WSU Nuclear Science Center The annual report for the WSU reactor facility is hereby submitted. The report covers the operating period from July 1, 2020 through June 30, 2021.

Respectfully Submitted, C. Corey Hines Director Enclosure cc: Hillary Bennett, Reactor Supervisor, Nuclear Science Center WA Department of Health, Office of Radiation Protection

2021 ANNUAL OPERATIONS REPORT WASHINGTON STATE UNIVERSITY TRIGA REACTOR FACILITY LICENSE R-76 FOR THE REPORTING PERIOD JULY 1, 2020 TO JUNE 30, 2021 NUCLEAR SCIENCE CENTER l Washington State University, Pullman, WA

2021 Annual Report TABLE OF CONTENTS

1. NARRATIVE

SUMMARY

OF OPERATION FOR FISCAL YEAR 2021 ................ 2

2. ENERGY AND CUMULATIVE OUTPUT ............................................................... 2
3. EMERGENCY SHUTDOWNS AND INADVERTENT SCRAMS ........................... 4
4. MAJOR MAINTENANCE ....................................................................................... 4
5. CHANGES, TESTS, AND EXPERIMENTS PERFORMED UNDER 10 CFR 50.59 CRITERIA.............................................................................................................. 5
6. RADIOACTIVE EFFLUENT DISCHARGES .......................................................... 6
7. PERSONNEL AND VISITOR RADIATION DOSES .............................................. 7
8. REACTOR FACILITY RADIATION AND CONTAMINATION LEVELS ................. 8
9. ENVIRONMENTAL MONITORING PROGRAM ................................................. 11 Washington State University Nuclear Science Center

2021 Annual Report

1. Narrative Summary of Operation for Fiscal Year 2021 A. Operating Experience Core 35A has accumulated 13,482 MWH from beginning of life (BOL) through June 30, 2021. During the reporting period of July 1, 2020 to June 30, 2021, a total of 1074 samples were irradiated, for 9492 user-hours. Additionally, 5 pulses greater than $1.00 of reactivity addition were performed during the reporting period. The quarterly operations summaries are shown in Table I.

B. Changes in Facility Design, Performance Characteristics, and Operating Procedures Related to Reactor Safety.

The Standard Operating Procedures revision 0.6 were approved by the Reactor Safeguards Committee on 4/14/2021.

C. Results of Surveillance Tests and Requirements The NLW-1000 was not calibrated according to procedure in January 2021 then used for a calorimetric power calibration. The detector was then not adjusted as procedure requires based on the results of the calibration. Staff noticed the channel read high and had it recalibrated. After recalibrating the channel another power calibration was not performed prior to operating. It was determined that the facility was operating with a Log-N channel that was not calibrated according to procedure. A power calibration was performed immediately to correct the issue.

All other surveillance tests and requirements were performed and completed within the prescribed time period.

2. Energy and Cumulative Output The quarterly operations summaries are given in Table I. The cumulative energy output since the 1967 TRIGA fuel core was put in to service is 1,792 megawatt days (MWD). The mixed Standard Fuel and 30/20 LEU Fuel Core 35A installed in 2008 has accumulated 562 MWD.

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2021 Annual Report Table I. Fiscal Year 2021 Summary of Reactor Operation1 Q3 2020 Q4 2020 Q1 2021 Q2 2021 Totals Hours of Operation 542 479 339 400 1759 Megawatt Hours 264 249 217 315 1045 Sample Irradiations 63 60 63 53 239 Samples 224 323 198 236 981 External Irradiations 21 26 21 25 93 Pulses > $1.00 1 2 0 2 5 User Hours 1774 2333 2268 3118 9492 1

Number of samples and sample irradiations do not include external client irradiations. User hours denotes the total user hours, including external client irradiations.

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2021 Annual Report

3. Emergency Shutdowns and Inadvertent Scrams During the reporting period, there were no emergency shutdowns.

The dates and causes of the sixteen inadvertent scrams are listed in Table II. No scrams were due to exceeding the limiting safety system setting or safety limit.

Table II. Inadvertent Scrams Date Description 10/16/2020 Trainee placed the mode selector switch into test instead of rundown while operating at 1.0 MW 10/27/2020 Sample holder hook fell into pool from the bridge while at 1.0MW and the operator scrammed the reactor.

12/9/2020 Manual scram due to a high area radiation alarm at the console. No abnormal radiation levels were observed and the cause was determined to be a failed area radiation monitor (ARM).

1/28/2021 High voltage failure on the Log-N Channel due to high temperature in the control room.

2/1/2021 High voltage failure on the Log-N Channel due to high temperature in the control room.

2/3/2021 High voltage failure on the Log-N channel. The control room temperature is no longer high however the channel is still failing.

2/8/2021 High voltage failure on the Log-N channel.

2/11/2021 High voltage failure on the Log-N channel.

3/20/2021 Trainee placed the mode selector switch into test instead of rundown while operating at 100 KW.

4/2/2021 High voltage failure on the Log-N channel.

4/30/2021 High voltage failure on the Log-N channel.

5/6/2021 High voltage failure on the Log-N channel.

5/26/2021 High voltage failure on the Log-N channel.

5/27/2021 High voltage failure on the Log-N channel.

6/1/2021 High voltage failure on the Log-N channel.

6/15/2021 Building power fluctuation that caused Control Element 1 and Control Element 3 magnets to disengage.

4. Major Maintenance Although they are not part of routine preventative maintenance, the below listed items were performed.

10/14/2020: Radiochemistry Lab 101 Intercom The intercom between the control room and lab 101 was repaired.

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2021 Annual Report 12/16/2020: Control Element 5 Control element 5 lower bearing, control rod shaft, and its housing were cleaned with WD-40 and lubricated.

1/20/2021: Fuel Temperature Test Function The test function connections were re-soldered.

1/28/2021 - 6/11/2021: NLW-1000 High Voltage Failure The high voltage cable, the J4 trips connector cable, transformers, and HV power supply in the NLW-1000 were replaced.

2/4/2021: The J4 Trips connector on the NLW-1000 was rewired with a new connector and cable assembly to add extra length needed to reduce tension on individual wires and ensure reliable connections.

5/11/2021: Bridge flasher/beeper The flasher and beeper required for bridge movement during BNC operations was reinstalled according to the schematics and is operational.

5/11/2021: Bridge Position Indicator The 10-turn pot for the bridge position indicator was replaced.

5. Changes, Tests, and Experiments Performed Under 10 CFR 50.59 Criteria A total of two (2) proposed changes to the facility were reviewed during the 2020-2021 year. All of the proposals were screened with the 10 CFR 50.59 requirements and found to screen out, thus allowing the changes to be made. The following changes were made to the facility under 50.59 criteria:
1) The console relays are failing more frequently and specific make and models are obsolete. Like for like replacements from the same manufacturer were determined by an electrical engineer. The relays are being replaced as needed and as time allows.
2) An electrical engineer has repaired and modified a spare NLW-1000. The current NLW-1000 was modified in house decades ago including a circuit board and relay inside the channel and an extra connector on the back. The modification of the spare does not change the channels ability to perform the same functions, it only uses the factory installed trips to perform the functions instead of adding superfluous components.

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2021 Annual Report

6. Radioactive Effluent Discharges A. Radioactive Liquid Effluent Releases The liquid effluent releases for the facility during the reporting period are provided in Table III.

Table III. Monthly Liquid Effluent Releases Month Volume (gallons)

July 2020 0 August 0 September 0 October 0 November 0 December 0 January 2021 0 February 3199 March 0 April 0 May 0 June 0 Approximately 3199 gallons of liquid effluents were released from the storage tank during the reporting period. Prior to discharge, a sample of the liquid in the tank was analyzed using gamma spectroscopy and liquid scintillation counting. The February gamma spectroscopy report indicated an activity of 0.00 µCi. A total of activity of 0.00 µCi was released as liquid effluent during the reporting period.

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2021 Annual Report B. Radioactive Gaseous Effluent Release During the reporting period, no emission of a measurable quantity of gaseous or particulate material with a half-life greater than eight days was detected. The argon-41 release did not exceed 20% of the effluent release limit. A total of 2.28 Ci of argon-41 was released, with an average argon-41 concentration of 1.16 x 10-10 µCi/mL of air, after environmental dilution. The argon-41 release and the pool water analysis is used in the 2021 Annual Report for Radioactive Air Emission License (RAEL-004), stack number 7. Per COMPLY v1.7, the reactor facility (stack 7) is in compliance at level 4 with an effective dose equivalent of 2.4 x 10-3 mrem/yr. The monthly releases from Ar-41 are summarized in Table IV.

Table IV. Monthly Argon-41 Releases2 Conc. After  % of DAC Month Quantity (Ci)

Dilution (µCi/mL) Limit July 2020 1.7E-01 1.0E-10 3.4E-03 August 9.5E-02 5.7E-11 1.9E-03 September 1.5E-01 9.5E-11 3.2E-03 October 8.4E-02 5.0E-11 1.7E-03 November 8.0E-02 5.0E-11 1.7E-03 December 2.9E-01 1.8E-10 5.8E-03 January 2021 1.3E-01 7.5E-11 2.5E-03 February 1.2E-01 7.8E-11 2.6E-03 March 2.9E-01 1.7E-10 5.7E-03 April 2.2E-01 1.3E-10 4.4E-03 May 3.2E-01 1.9E-10 6.3E-03 June 3.4E-01 2.1E-10 7.0E-03 C. Radioactive Solid Waste Disposal During the reporting period, 1.32 x 10-6 mCi in 7.35 cubic feet of non-compacted solid waste was transferred to the WSU Radiation Safety Office for packaging and disposal.

7. Personnel and Visitor Radiation Doses 2

Quantity released based on 4500 CFM effluent of ventilation system in AUTO mode of operation. Concentration after dilution is based on 10 CFR 20 effluent release limit of 1.0 x 10-8 µCi/mL for Ar-41 (Table 2, Col.1), and a dilution factor of 3.4 x 10-3 (WSU Technical Specifications 3.5.2). DAC limits are based on 10 CFR 20 derived air concentration limit of 3.0 x 10-6 µCi/mL for Ar-41 (Table 1, Col. 3) and a dilution factor of 3.4 x 10-3.

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2021 Annual Report The quarterly doses of the WSU Nuclear Science Center reactor staff and experimenters are given in Table V. The maximum quarterly dose to a reactor staff member was 90 mrem, whole body. A total of 468 individual persons visited the Nuclear Science Center during the reporting period, of which 98 entered a controlled access area (CAA).3 A total of 1 group tour, consisting of 5 individuals, visited the center during the reporting period, also entering a CAA. A total of 10 virtual tours were given consisting of 163 individuals. All doses were less than or equal to 0.2 mrem as determined by digital pocket dosimeters.

Table V. Quarterly Reactor and Experimenter Staff Dose4 (mrem)

Badge No. Q3 2020 Q4 2020 Q1 2021 Q2 2021 706 -- -- 25 30 10921 75 46 24 41 12176 19 30 28 29 705 -- -- 24 32 11975 26 27 29 34 12216 24 32 28 29 12033 25 30 27 27 701 -- -- 29 35 11937 35 30 29 30 8141 24 27 26 29 12212 28 30 34 30 698 -- -- 36 29 11986 25 31 29 29 10916 49 31 25 25 12207 26 28 30 32 704 -- -- 25 29 12204 25 7 -- --

703 -- -- 26 30 700 -- -- 29 7 12030 27 29 30 33 11965 90 41 82 32 400 15 -- -- --

1160 -- -- -- 13

8. Reactor Facility Radiation and Contamination Levels The limit of quantification (LOQ) for building removable contamination determination survey samples as measured by liquid scintillation assay is 9.03 x 10-8 Ci/cm2; the 3

A controlled access area is an area in the building where radioactive materials are used or stored and is a part of the licensed reactor facility.

4

-- denotes data not available either due to departure from the facility or new personnel starting at the facility. An M denotes that the dosimeter reading was less than or equal to the background radiation level for that quarter.

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2021 Annual Report survey sample data that was collected for removable contamination determination were averaged over one year. Routine building surveys showed average levels of removable activity to be less than the LOQ for all non-CAAs.

Table VI. Average Removable Contamination for Weekly Monitoring in CAAs and Non-CAAs5 Measured Activity Location Above LOQ (µCi/cm2) 201B M 201A M 201 Reactor Bridge Steps M 201 Sample Drop Tube M 201 Reactor Bridge South M 201 Reactor Bridge North M 201 Experimenter Platform 2.2E-07 201 Laboratory Benches M 201 Floor South M 201-C Heat Exchanger Floor M 201 Floor North M 106 Ion Exchanger Pit M 101-A Purification Pump Pit M 101 Doorway M 101 Sample Preparation Bench M 101 Sample Drop Hood #2 M 101 Hood #1 M 101 Hood #2 M 101 Hood #3 M 101 Hood #4 M 101 Shipment Bench M RAM Storage Safe M 101 Island M 101 North lab Bench M B21 Panoramic Irradiator M B21 Floor M 2 South Floor M 2 Thermal Column M 2 Thermal Column Floor M 2 North Floor M 2 Cave Floor West M 2 Cave Floor East M 5

Bolded text indicates a non-CAA. Regular text indicates a CAA. M indicates the value is below the LOQ value of 9.03 x 10-8 Ci/cm2.

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2021 Annual Report The results for the routine area radiation surveys of the building in CAAs and non-CAAs are given in Table VII. The highest average dose rate for a single location in a CAA was 2.95 mrem/hr, which occurred in Room 2 East Cave. This value is less than the limit for CAAs. The lowest average dose rate in a CAA was 0.04 mrem/hr (a level considered background), which occurred in Room 2 Thermal Column. The average dose rate in the radiochemistry sample hoods (a non-CAA) was 0.06 mrem/hr. The East and West cave are secured storage areas that are designed to house radioactive sources, and provide shielding. The space is posted as a high radiation area.

Personnel do not typically work in this area and it is locked when not in use.

Table VII. Average Radiation Dose Rates for Weekly Monitoring in CAAs and Non CAAs6 Average Dose Location Rate (mrem/hr)

Room 201 B 0.05 Room 201 A 0.04 Room 201 Bridge 0.79 Room 201 Benches 0.07 Room 201 South 0.33 Room 201 East 0.51 Room 201 C Heat Exchanger 0.05 Room 201 North 0.42 Room 106 Ion Exchanger Pit 0.87 Room 101 A Purification Pit 1.15 Sample Storage 0.24 Room 101 Doorway 0.04 Room 101 Sample Prep Bench 0.04 Room 101 Sample Drop Hood 0.04 Room 101 Shipping Bench 0.05 Room 101 Hood 1 0.06 Room 101 Hood 2 0.08 Room 101 Hood 3 0.04 Room 101 Hood 4 0.06 Room B21 Panoramic Irradiator 0.04 Room 2 South 0.26 Room 2 Thermal Column 0.04 Room 2 North 0.10 Room 2 West Cave 0.62 Room 2 East Cave 2.95 6

Bolded text indicates a non-CAA. Regular text indicates a CAA. M indicates the value is below the LOQ value of 9.03 x 10-8 Ci/cm2.

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2021 Annual Report

9. Environmental Monitoring Program The environmental monitoring program is used to determine the offsite background radiation levels; thermoluminescent dosimeters (TLDs) are used to make the measurements. The offsite radiation monitoring program is required by the Technical Specifications. The TLDs that are used for offsite monitoring are designated as TLD numbers 3, 7, 9, 15 through 35, and 39 through 44. The average background radiation level is then compared to the nearest occupied dwelling.

Average quarterly dose rates for offsite locations are listed in Table VIII and are used to calculate the Technical Specification threshold of 20% above the background radiation level and compared to the limiting values which are listed in Table XI. The average environmental radiation levels for the closest offsite point of extended occupancy is listed in Table X. Table IX shows the quarterly environmental radiation levels for those TLDs located at onsite locations. The onsite locations are not required to be compared to background radiation levels.

The closest offsite points of extended occupancy are compared in Figure 1 to both the background radiation levels and the 20% above background radiation levels. The ALARA effluent release limits in Technical Specification 3.5.2(3) specify that annual radiation exposure due to reactor operation, at the closest offsite extended occupancy, shall not, on an annual basis, exceed the average offsite background radiation by more than 20%. For the reporting period, the average background radiation dose rate for off-site locations was 0.34 mrem/day, while the average radiation dose rate at the closest extended occupancy area 600 meters away was 0.31 mrem/day. This result indicates that no exposure level above normal background radiation were found, and that no dose levels exceeded Technical Specifications requirements for an offsite area of extended occupancy.

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2021 Annual Report Table VIII. Environmental Radiation Levels at Offsite Locations7,8 Q3 Q4 Q1 Q2 Location Average 2020 2020 2021 2021 Fence E of NSC 0.28 0.28 0.34 0.36 0.32 Fence, N of Rad Waste Shed 0.35 0.33 0.39 0.35 0.36 Fence directly N Rad Waste Shed 0.91 0.52 0.44 0.44 0.58 S NSC, on parking lot fence 0.27 0.30 0.37 0.31 0.31 Fence S Roundtop Dr, 10th pole W of pole C14 0.35 0.33 0.41 0.36 0.36 Telephone pole C12 0.32 0.33 0.38 0.35 0.34 Telephone pole near golf course gate 0.28 0.30 0.38 0.34 0.33 E across fairway on pine tree 0.29 0.32 0.39 0.32 0.33 Maple tree #54 along driving range 0.29 0.29 0.33 0.32 0.31 NW to fence uphill from driving range 0.32 0.33 0.37 0.40 0.35 Follow fence E to fence corner 0.32 0.34 0.43 0.37 0.37 S to lone spruce tree near water hazard 0.29 0.31 0.35 0.32 0.32 Roundtop hill park, NW fence corner 0.28 0.28 0.39 0.34 0.32 Deciduous tree edge of 18th green 0.33 0.33 0.39 0.42 0.37 6ft pine tree, 3rd W down cart path from 0.32 0.36 0.37 0.33 0.35 clubhouse 3rd to last tree after gap in same line of trees 0.29 0.29 0.33 0.32 0.31 SW to fence along path near 2nd to last tee box 0.32 0.31 0.38 0.36 0.35 at bottom hill Follow fence partway up hill after fence turns S 0.31 0.34 0.38 0.36 0.35 Follow fence, 15th pole E after fence turns W 0.32 0.32 0.38 0.41 0.36 Follow fence about halfway between last TLD 0.33 0.34 0.37 0.36 0.35 and corner Largest bush S of NSC 0.37 0.35 0.38 0.37 0.37 2nd fence S NSC, W end at gate 0.29 0.30 0.39 0.33 0.33 S Fairway Rd, 1st light post on right 0.29 0.29 0.41 0.35 0.34 S Fairway Rd, 2nd light post on right 0.27 0.31 0.37 0.33 0.32 Ellis Way and Hog Lane sign 0.29 0.31 0.37 0.37 0.34 Bottom of radio antenna hill, fence next to shrub 0.30 0.31 0.37 0.35 0.33 left of gate 3rd fence S of NSC, SE corner, cow pasture 0.31 0.31 0.34 0.40 0.34 Airport fence W end runway at gate 0.30 0.30 0.34 0.37 0.33 Fence/entry bar E of Jewett Observatory 0.30 0.32 0.35 0.32 0.32 Railing at Terrell Mall / Library 0.26 0.28 0.35 0.30 0.30 7

Offsite defined by the Technical Specification 1.0 and 5.1.1 as any location, which is outside the site boundary. The --

indicates a TLD which was missing.

8 Dose rate in mrem/day.

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2021 Annual Report Table IX. Environmental Radiation Levels at Onsite Locations9,10 Q3 Q4 Q1 Q2 Location Average 2020 2020 2021 2021 E lower loading dock 0.30 0.29 0.34 0.33 0.32 Pool room truck door fence S end 0.39 0.50 0.43 0.44 0.44 Pool room truck door fence N end 0.35 0.71 0.47 0.37 0.47 E wall rad waste shed 0.34 0.49 0.43 0.39 0.41 N wall rad waste shed 0.37 0.57 0.43 0.40 0.44 Cooling tower fence, NE corner 0.49 0.59 0.56 0.52 0.54 Room 101 window 0.33 0.36 0.44 0.39 0.38 Railing next to upper liquid waste tank 0.33 0.36 0.41 0.39 0.37 Room 2 truck door fence 0.32 0.36 0.41 0.33 0.35 Transformer vault vent louvers 0.33 0.36 0.42 0.37 0.37 NSC main entrance, light fixture 0.37 0.37 0.43 0.43 0.40 NSC roof, pool room vent stack 0.26 0.24 0.37 0.32 0.30 NSC roof, guide wire E end of building 0.26 0.27 0.38 0.27 0.29 NSC roof, E pool room vent support leg 0.49 0.45 0.62 0.51 0.52 NSC roof, air conditioning support leg 0.30 0.28 0.40 0.26 0.31 NSC roof, W pool room vent support leg 0.41 0.48 0.75 0.63 0.57 Table X. Environmental Radiation Levels for the Closest Offsite Point of Extended Occupancy10 Q3 Q4 Q1 Q2 Location Average 2020 2020 2021 2021 Apt complex C, gas meter 0.27 0.29 0.33 0.34 0.31 Apt complex B, gas meter 0.26 0.30 0.34 0.32 0.31 1st fence S apt complex A 0.31 0.27 0.35 0.31 0.31 Table XI. Background Environmental Radiation Levels10 Q3 Q4 Q1 Q2 Description Average 2020 2020 2021 2021 Background radiation levels 0.31 0.32 0.37 0.35 0.34 20% above background radiation levels 0.37 0.38 0.45 0.42 0.40 9

Onsite defined by the Technical Specification 1.0 and 5.1.1 as any location within the site boundary. The -- indicates a TLD which was missing.

10 Dose rate in mrem/day.

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2021 Annual Report 0.50 0.45 0.40 0.35 Dose Rate (mrem/day) 0.30 Apartment Complex A 0.25 Apartment Complex B Apartment Complex C 0.20

Background

0.15 20% Above Background 0.10 0.05 0.00 Q3 2020 Q4 2020 Q1 2021 Q2 2021 Average Quarter Figure I: Environmental radiation levels for the closest offsite point of extended occupancy radiation levels as compared to background radiation levels and 20% above background radiation levels.

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