ML25255A094
| ML25255A094 | |
| Person / Time | |
|---|---|
| Site: | University of Wisconsin |
| Issue date: | 09/08/2025 |
| From: | Agasie R Univ of Wisconsin - Madison |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML25255A094 (1) | |
Text
THE UNIVERSITY OF WISCONSIN NUCLEAR REACTOR LABORATORY FISCAL YEAR 2024-2025 ANNUAL OPERATING REPORT Prepared to meet reporting requirements of:
U. S. Nuclear Regulatory Commission License R-74 Docket 50-156 Technical Specification 6.7.1(1)
Prepared by :
Robert J. Agasie College of Engineering THE. UNJVE.RSITY
q/----
WISCONSIN MADISON
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 1 of 12 TABLE OF CONTENTS A.
SUMMARY
OF OPERATIONS..................................... 2 1.
INSTRUCTIONAL USE.................................... 2 2.
OUTREACH AND COMMUNITY SERVICE....................... 2
- 3.
IRRADIATION SERVICES................................. 4
- 4.
CHANGES IN PERSONNEL, FACILITY AND PROCEDURES........ 5 5.
RESULTS OF SURVEILLANCE TESTS AND INSPECTIONS........ 6 B.
OPERATING STATISTICS AND FUEL EXPOSURE.................... 6 C.
EMERGENCY SHUTDOWNS AND INADVERTENT SCRAMS................ 7 D.
MAI NTENANCE............................................... 7 E.
CHANGES IN THE FACILITY OR PROCEDURES AND EXPERIMENTS REPORTABLE UNDER 10 CFR 50. 59............................. 8 F.
SUMMARY
OF RADIATION EXPOSURE OF PERSONNEL................ 9 G.
RESULTS OF ENVIRONMENTAL SURVEYS.......................... 9 H.
RADIOACTIVE EFFLUENTS.................................... 10 TABLE 1 TABLE 2 ANNUAL ENVIRONMENTAL MONITORING DOSE DATA........... 11 EFFLUENT FROM STACK................................. 12
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 A.
SUMMARY
OF OPERATIONS
- 1.
INSTRUCTIONAL USE Page 2 of 12 Nuclear Engineering (NE) 231, "Introduction to Nuclear Engineering" was offered in the spring semester with an enrollment of 57 students.
The course incorporates an engineering design challenge utilizing the reactor.
The students designed, manufactured, and tested a light-sensitive detector to measure the Che renkov radiation emitted from the reactor.
The students then determined how that data correlated with the actual reactor power level.
Four sections of NE 427, "Nuclear Instrumentation Laboratory", were offered during the academic year with a total enrollment of 37 students.
Several NE 427 experiments use materials that are activated in the reactor.
One experiment requires students to make measurements of radiation levels in the Reactor Laboratory.
Two sections of NE 428, "Nuclear Reactor Laboratory", were offered during the academic year with a total enrollment of 27 students.
Three experiments require exclusive use of the reactor ("Critical Experiment", " Control Element Calibration", and "Pulsing") requiring a total of 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> of exclusive reactor use.
Other laboratory sessions use materials that have been irradiated in the reactor ("Fast Neutron Flux Measurements" and "Resonance Absorption")
The Reactor Laboratory continues its commitment to educational outreach programs and community service.
A listing of individual schools and educational programs that received services is provided below in section A.2 of this report.
- 2.
OUTREACH AND COMMUNITY SERVICE Most outreach activities included a reactor tour with a discussion on applications of nuclear energy and uses of the UW nuclear reactor.
More immersive activities are offered when requested, including hands-on demonstrations of radiation detection and shielding.
Services provided to the community typically involved analyzing swipe tests for leak checks of radioactive sources and performing detector calibrations for non-profit educational institutions.
UWNR ANNUAL REPORT-Fiscal Year 2024 - 2025 K -
12 Educational Programs Participating Organization Abundant Life Christian High School BECOME Program Scouting America Edgerton Middle School Marshall High School Page 3 of 12 No. of Participants 7
ProCSI : Promoting Computational Science Initiative 15 309 10 15 45 Post Secondary Educational Programs Participating Organization No. of Participants Energy Analysis & Policy (EAP) Certificate Program 12 Gyeongsang National University 21 Institute of Science Tokyo 6
UW Chemistry 801 6
UW Housing 19 UW InterPro Grad Student Program 14 UW Medical Physics ASSURE Program 10 UW NEEP Admitted Undergrad Students Program 11 UW NEEP Grad Student Recruitment Program 15 UW NEEP Undergrad Student Recruitment Program 12 Professional Development Programs Participating Organization North Central Chapter of the Health Physics UW College of Engineering Safety Department UW Department of Information Technology UW History Department UW Materials Research Science & Engineering Wisconsin Department of Health Services Wisconsin Public Utility Institute Community Outreach Participating Group Cardinal Glass Dane County Area FLOGgers UW Alumni No. of Participants Society 5
32 26 14 Center 13 7
33 No. of Participants 5
12 7
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Community Service Participating Institution Beloit College OW-Whitewater Department of Physics OUTREACH AND COMMUNITY SERVICE USER
SUMMARY
Organizations : 28
Participants:
681 3.
IRRADIATION SERVICES Page 4 of 12 There were 164 individual samples irradiated during the year.
Samples accumulated 40. 9 irradiation space hours and 135.9 sample hours.
Experiments accumulated 5.0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> of neutron irradiation.
Department of Medical Physics, UW-Madison 1 sample, 0.1 sample hours Irradiation of TLD-600 and TLD-700 thermoluminescent dosimetry chips for measurement of neutron dose sensitivity.
Department of Nuclear Engineering & Engineering Physics, UW-Madison Reduced Activation Ferritic Martensitic Steels Project 2 samples, 4. 1 sample hours Irradiation of Reduced Activation Ferritic Martensitic (RAFM) steels for benchmarking of activation-decay predictions.
Department of Nuclear Engineering & Engineering Physics, UW-Madison NE 231 5. 0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> of neutron irradiation An undergraduate engineering design challenge utilizing the reactor.
Students designed, manufactured, and tested a light-sensitive detector to measure the Cherenkov radiation emitted from the reactor while operating.
The students correlated the detector data to the actual reactor power level.
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 5 of 12 Department of Nuclear Engineering & Engineering Physics, UW-Madison NE 427 115 samples, 104.7 sample hours Production of foil sources for radi ation detector experiments and activation of samples for the neutron activation analysis experiment.
Department of Nuclear Engineering & Engineering Physics, UW-Madison NE 428 24 samples, 23. 0 sample hours Irradiation of foils for resonance absorption measurements and fast neutron flux measurements.
UW Nuclear Reactor Laboratory 2 samples, 2. 0 sample hours Production of calibration sources for required reactor measurements, flux measurements and development of methods for instrumental neutron activation analys i s.
ManTech 20 samples, 2. 0 sample hours NAA characterizing environmental samples.
4.
CHANGES IN PERSONNEL, FACILITY AND PROCEDURES Personnel changes during the year were as follows :
The fol l owing individuals were appointed as Reactor Operators :
Name Nicholas Tierney Li ncoln Ogren Gerson Esquivel Garcia License OP-505848 OP-505849 OP-505850 Effective Date July 9, 2024 Jul y 9, 2024 Jul y 9, 2024 The following Reactor Operator Licenses were terminated :
Name Al ison Q. Holden Daniel P. Mancheski License OP-504875 OP-504876 Effective Date May 22, 2025 May 22, 2025
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 6 of 12 Facility changes reportable under 10 CFR 50. 59 are detailed in section E of this report.
Other changes to the facility included replacing the active sampling aspirating fire detection system with a passive linear heat wire fire detection system.
All procedures were reviewed with the proposed revision approved by the Reactor Safety Committee.
No changes to operating procedures related t o react or safety occurred during the year.
5.
RESULTS OF SURVEILLANCE TESTS AND INSPECTIONS The program of inspection and testing of reactor components continues, satisfactorily meeting procedural acceptance criteria.
Inspection of underwater components during the annual maintenance showed no deterioration or abnormal wear.
The pool leak surveillance program continues to monitor the pool make - up volume and pool water radioactivity.
The pool leak surveillance program indicated that no water effluent had been released to the environment this year.
B.
OPERATING STATISTICS AND FUEL EXPOSURE Operating Period Fiscal Year 2024 - 2025 Cumulative TRIGA 30/20 LEU Critical Hours 214. 94 4, 647. 73 MW-Hours 150.32 3, 029. 00 Runs Pulses 74 13 2, 181 480 Core K21-R6 was operated throughout the year.
The excess reactivity of this core was determined to be 3. 929 %p.
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 7 of 12 C.
EMERGENCY SHUTDOWNS AND INADVERTENT SCRAMS There was one automatic SCRAM during the year.
July 15, 2024 ; SCRAM from picoammeters number 1 and 2.
While performing the rod bump rising period method for control element calibration, a reactor operator lost operational awareness.
Following a control element pull the operator was logging the end position of the control element and failed to up range picoammeters number 1 and 2 from the l0W range to the 100W range.
As a result, a reactor SCRAM from a neutron high fl ux trip at 125% on the l0W range occurred.
D.
MAINTENANCE The Preventive Maintenance Program continues to ma i ntain equipment and systems in good condition.
Demineralizer r esins were replaced on August 7, 2024.
Any corrective maintenance that may have been performed as a follow up action necessary for reactor restart following an emergency shutdown or automatic SCRAM would be covered in section C of this report.
Additional corrective maintenance was performed on the following installed systems, structures, and components (SSC) as described in the Safety Ana l ysis Report (SAR) :
On July 9, 2024, following the semi - annual check o f the Log Count Rate Monitor (LCRM), the trip output connector was accidentally shorted damaging one of the pins.
The connector was replaced and the LCRM returned to service.
On July 30, 2024, the Stack Air Monitor (SAM) particulate monitor was spuriously going into trouble and then resetting automatically.
Extensive troubleshooting revealed the detector was failing.
The detector was replaced and following recalibration the unit was returned to service.
Following completion of the weekly reactor ventilation operability checks on August 9, 2024, the air handler, AHU-5, would not restart.
Troubleshooting revealed one leg of
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 8 of 12 the 24VAC transformer to be loose on the control circuit terminal block.
The wire was retightened and the air handler responded as designed.
It was observed on December 9, 2024, that the reactor ventilation exhaust flow rate was lower than expected.
Investigation revealed that the east fire damper in the main exhaust duct was closed due to the f usible link failing.
The fusible link was replaced and the damper reopened.
The system was observed to be operating normally.
On December 10, 2024, the reactor ventilation exhaust fan EF-7 tripped off requiring exhaust fan EF-8 to automatically spin up.
Troubleshooting revealed the A phase of the contactor in the motor control center (MCC) bucket was running hotter than the other two phases because of pitting of t he A phase contacts.
All the contactor contacts were replaced, and thermal imaging showed the contractor was at nomi nal temperature.
The fan was returned to service.
On January 27, 2025, one of the factory sealed motor bearings in the pump to the Reactor Water Make-Up/Clean Up system had seized.
The pump was replaced with a spare pump.
The seized motor bearing was replaced, and the rebuilt pump was placed in storage as a spare.
E.
CHANGES IN THE FACILITY OR PROCEDURES AND EXPERIMENTS REPORTABLE UNDER 10 CFR 50.59 There was one change to the facility, reportable pursuant to 10 CFR 50. 59, completed during the year.
The safety evaluation for the modification concluded a license amendment pursuant to 10 CFR 50.90 was not required.
The modification is summarized below.
The faci l ity incorporates a back flow preventer that ensures water within the facility cannot potential l y contaminate the city water supply.
The back flow preventer was in the area of the Reactor Water Make Up/Clean Up Systems and approximately 8 feet off the beam port floor.
This made it difficult to work on when conducting annual
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 9 of 12 testing.
Therefore, t he back flow preventer was relocated from the Reactor Water Make Up/Clean Up System area to the Reactor Cooling System area at a working height of 4 feet from the floor.
Figure 5-5 in the Safety Analysis Report (SAR) was updated to reflect this change.
There were no changes to procedures, reportable pursuant to 10 CFR 50.59, completed during the year.
There were no new experiments, reportable pursuant to 10 CFR 50.59, conducted during the year.
F.
SUMMARY
OF RADIATION EXPOSURE OF PERSONNEL (01/01/24 -
12/31/24)
The personnel radiation monitoring program at the University of Wisconsin for the past calendar year used Landauer Luxel brand monitors for whole body and extremity exposure.
No personnel received any significant radiation exposure for the above period.
The highest annual whole-body doses recorded were 17 mrem deep dose equivalent (ODE) and 16 mrem shallow dose equivalent (SOE).
The highest annual extremity dose was 51 mrem and the highest annual dose to the lens of the eye was 17 mrem.
The highest dose received by a member of the public visiting the reactor lab was 0. 79 mrem, as measured by Mirion brand, model DMC 3000 electronic personal dosimeters.
Monthly radiation surveys continue to demonstrate acceptable radiation dose rates within the reactor laboratory and no contamination.
G.
RESULTS OF ENVIRONMENTAL SURVEYS (01/01/24 -
12/31/24)
The environmental monitoring program at the University uses Landauer Luxel brand area monitors located in areas surrounding the reactor laboratory.
Table 1 indicates the dose a person would have received if continuously present in the indicated area for the entire 202 4 calendar year.
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 10 of 12 H.
RADIOACTIVE EFFLUENTS
- 1.
LIQUID EFFLUENTS No Liquid waste was discharged to the sanitary sewer from the facility during the year.
No liquid effluents were released to the environment during the year.
2.
EXHAUST EFFLUENTS Table 2 presents information on stack discharges during the year.
- 3.
SOLID WASTE No solid waste was transferred from the facility during the year.
f UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 11 of 12 TABLE 1 ANNUAL ENVIRONMENTAL MONITORING DOSE DATA (01/01/24 - 12/31/24)
Location Annual Dose (mrem)
Dose Inside Reactor Laboratory Stack
<l Highest Dose in Non-restricted Area 2
Highest Dose in Occupied* Non-restricted Area
<l Average Dose in all Non-restricted Areas 0. 13 (26 Monitor Points)
- Occupied areas include classrooms, offices, and lobbies/meeting areas where an individual might reasonably spend more than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> per day
UWNR ANNUAL REPORT-Fiscal Year 2024-2025 Page 12 of 12 TABLE 2 EFFLUENT FROM STACK
- 1.
Particulate Activity There was no discharge of pa r ticulat e activity above background levels.
2.
Gaseous Activity - All Argon-41 Activity Maximum Average Month Discharged Concentration Concentration (Curies)
(µCi/ml)
(µCi/ml)
July 2024 0.006 2.650E- 07 3. 660E-1 0 August 0.005 2.360E- 07 3. 064E-10 September 0. 101 4. 250E-07 6. 435E-09 October 0. 176 7. l00E-07 l.085E-08 November 0. 138 7. 460E- 07 9.039E-09 December 0. 061 7. 210E-07 3. 883E-09 January 2025 0.026 4. 350E- 07 1.621E-09 February 0. 041 3.380E- 07 2. 735E- 09 March 0. 024 7.210E-07 l. 459E-09 April 0. 134 5. 180E-07 8. 362E-09 May 0.0 18 3. 330E-07 l.096E-09 June 0. 017 2. 590E-07 1. 072E-09 Total Maximum Average 0.747 7. 460E-07 3. 936E-09 Using t he Gaussian Plume model, as described in section 13. 1. 7. 2 of the Safety Analysis Report for the University of Wisconsin Nuclear Reactor ", a concentration of 6E-5
µCi/ml at the stack discharge would result in a maximum air concentration of lE-8 µCi/ml at any point downwind.