ML24100A040

From kanterella
Jump to navigation Jump to search
Enclosure - Idaho State University: Annual Operating Report for 2023 Calendar Year
ML24100A040
Person / Time
Site: Idaho State University
Issue date: 04/08/2024
From:
Idaho State University, Pocatello
To:
Office of Nuclear Reactor Regulation
Shared Package
ML24100A043 List:
References
Download: ML24100A040 (1)


Text

Idaho State University AGN-201m Reactor 2023 Annual Report Page 1 of 9

Idaho State University AGN-201M Reactor Facility License R-110, Docket No. 50-284 Annual Operating Report for 2023 Calendar Year

1. Narrative Summary

A. Changes in Facility Design, Performance Characteristics, and Operating Procedures

1) 1/04/2023: A new Data Acquisition System (DAS) was installed on the AGN-201 console based on ISU-50.59-4 analysis.
2) 5/25/2023: A water collection device was installed in reactor skirt area to divert and collect water leaking from the shield tank (ISU-50.59-2023-2).
3) 6/15/2023: A License Amendment Request for Facility License R-110 Docket Number 50-284 was submitted to remove channel 2 low scram, remove channel 3 5% low scrams for all ranges below and including the start up range, rewording of Technical Specifications Section 3.2(d), and removal of Unit A and Unit B from Technical Specifications Table 3.1.
4) 9/20/2023: The DAS was disconnected from the AGN console due to the discovery of abnormal reactor power indications when the DAS computer was de-energized and a Reportable Occurrence Report (ML23258A194) was submitted to the Nuclear Regulatory Commission (NRC).
5) No major changes to the Facility Design, Performance Characteristics, and Operating Procedures were made in 2023. However, a replacement AGN-201 tank was acquired from the University of Utah and two replacement ion chambers were received to replace the aging channel 2 and 3 detectors.

B. Results of major Surveillance Tests and Measurements

1) The period, count rate, and power level measuring channels were calibrated and set points were verified. Channels 1, 2, & 3 were tested on 6/12/2023.
2) Power level (6/12/2023) and period check (6/12/2023) experiments were performed with satisfactory results.
3) The shield water tank was inspected (5/09/2023) and no leaks or excessive corrosion were observed. The Water Level interlock tested satisfactorily (5/09/2023).
4) The Seismic Displacement & Temperature interlocks were tested and found satisfactory on 5/09/2023.
5) Control element capsules (cladding) were inspected (5/16/2023) and found to be in good condition with no evidence of deterioration since the previous inspection
6) The control rod drive mechanisms were inspected (5/16/2023) and tested with satisfactory results.

Idaho State University AGN-201m Reactor 2023 Annual Report Page 2 of 9

7) Ejection times were measured for all SCRAM-able rods (SR-1, SR-2, and CCR) and were found to be 0.12, 0.11, and 0.10 seconds, respectively. The requirement that ejection times be less than 1 second is satisfied.
8) The reactivity worth of the Fine Control Rod, Safety Rods 1 and 2, and the Course Control Rod were measured. The time to drive each rod fully into the core was measured as part of performing Maintenance Procedure 1. The largest reactivity insertion rate is 0.0282, which is less than the tech spec limit of 0.065.
9) The shutdown margin (SDM) with the most reactive SCRAM-able rod and the Fine Control Rod fully inserted was determined to be 2.2173 % (at maximum allowable k excess 0.65. This value meets the tech spec requirement that the SDM be greater than 1 %.

C. NRC Inspections

The annual inspection was conducted by Craig Bassett on July 31, 2023-August 3, 2023.

Two violations of NRC requirements were identified. Contrary to 10CFR55.53, the NRC inspector found that two senior reactor operators with active licenses did not have a biennial medical examination. A Notice of Violation was sent to ISU from the NRC on January 9, 2024 and a response to the NOV was sent by ISU to NRC on January 25, 2024.

2. Operating History and Energy Output

The reactor was operated at power levels up to 4.5 Watts for a total of 189.3052 Watt-hours of thermal energy during this reporting period. A summary of monthly operations for 2023 is given in Table I. Table I. Summary of Monthly Reactor Operations (1 January 2023 through 31 December 2023)

Year Totals January 27.1155 Watt-hr February 34.6468 Watt-hr March 11.1593 Watt-hr April 35.6533 Watt-hr May 0.0000 Watt-hr June 24.4447 Watt-hr July 13.9333 Watt-hr August 20.2358 Watt-hr September 0.2770 Watt-hr October 16.8317 Watt-hr November 4.9482 Watt-hr December 0.0597 Watt-hr

Idaho State University AGN-201m Reactor 2023 Annual Report Page 3 of 9

Total 189.3052 Watt-hr 0.1893 kWatt-hr

The 0.18931064 kWatt-hr consumed 8.305.4 µgrams of U-235 using Equation (1)

3600 6.2421012 1 1.17 235 1 235 235 235 235 = () (1 )( 1 )(200 )( 1 )(6.0221023 235)(1 235) (1)

During the calendar year, several students went through reactor operator training. During the calendar year, no students took the NRC licensing exam.

3. Unscheduled Events and Inadvertent SCRAMS

A. Unscheduled Events

On 1/17/2023, Channel 2 and 3 DAS resistors to ground removed to fix strange readings on channel 2. FCR down limit switch adjusted due to down light not coming on when FCR down.

On 4/17/2023, water on the floor in reactor skirt was discovered. Water was cleaned up and analyzed and no contamination was found. Reactor Administrator and Reactor safety Committee (RSC) were informed. Over the course of the next several weeks, all control rods were removed and inspected, graphite was removed and inspected from the thermal column, and the beam ports were inspected to attempt to determine the source of the water. A water collection device was fabricated to divert and collect the water as it leaked from the shield tank. A reactor restart plan was developed and approved by the RSC on 6/5/2023.

On 6/27/2023, the magnets on pushbutton would not push in and energize the magnets. After investigating and troubleshooting, it was determined that the scram button connection was dirty and not allowing the connection to be reset.

The scram button connection was cleaned and operation returned to normal.

On 9/14/2023, it was discovered that the DAS was causing abnormal response to channel 1 and 2 power indication when the DAS is de-energized. The reactor was shut down and the Reactor Administrator and RSC were informed. A Reportable Occurrence was submitted to NRC on 9/15/2023. On 9/20/2023, the wires from the DAS system were disconnected from the reactor console and the reactor was returned to operational status.

On 11/30/2023, Safety Rod 1 carriage failed to return to down position during a rod drop test. The down fuse for Safety Rod 1 was replaced and the reactor was returned to operational status.

B. Inadvertent SCRAMS and Actions Taken

Idaho State University AGN-201m Reactor 2023 Annual Report Page 4 of 9

There were 26 inadvertent scrams during this reporting period. Table II summarizes the inadvertent scrams, known or suspected cause, actions taken and resolution.

Table II. Summary of Inadvertent Scrams (1 January 2023 through 31 December 2023)

Inadvertent scrams Date Time Scram Cause Resolution Action Type Channel 3 Electrical New 1/24/2023 13:15 Low Noise detectors on Restart order Channel 3 Electrical New 1/26/2023 16:51 Low Noise detectors on Restart order Channel 3 Electrical New 1/30/2023 15:09 Low Noise detectors on Restart order Channel 2 Electrical New 2/8/2023 13:42 & 3 Low Noise detectors on Restart order Low Tank Water Heaters used 2/9/2023 12:24 Temp Temp < 15C to warm Shutdown room Channel 2 Electrical New 2/13/2023 14:27 & 3 Low Noise detectors on Restart order Channel 2 Electrical New 2/15/2023 10:31 & 3 Low Noise detectors on Restart order Channel 2 Electrical New 2/15/2023 10:42 & 3 Low Noise detectors on Restart order Channel 2 Electrical New 2/15/2023 14:43 Low Noise detectors on Restart order Channel 2 Electrical New 2/28/2023 9:28 Low Noise detectors on Restart order Channel 2 Electrical New 3/3/2023 9:09 Low Noise detectors on Restart order Channel 3 Electrical New 3/27/2023 14:20 Low Noise detectors on Restart order

Idaho State University AGN-201m Reactor 2023 Annual Report Page 5 of 9

Channel 3 Electrical New 3/27/2023 17:06 Low Noise detectors on Shutdown order Instruct 3/29/2023 14:30 Channel 3 Operator operator to Restart Low Error pay attention to console Channel 2 Electrical New 4/10/2023 14:20 Low Noise detectors on Restart order Channel 2 Electrical New 6/7/2023 11:54 Low Noise detectors on Restart order Channel 2 Electrical New 7/13/2023 14:00 Low Noise detectors on Restart order Channel 2 Electrical New 8/30/2023 14:20 Low Noise detectors on Restart order Channel 2 Electrical New 8/31/2023 13:07 Low Noise detectors on Restart order Channel 3 Electrical New 9/6/2023 18:10 Low Noise detectors on Restart order Channel 3 Electrical New 9/6/2023 18:20 Low Noise detectors on Restart order Adjust 10/4/2023 17:46 Channel 2 Setpoint set setpoint Restart High too low when SP2 performed Channel 2 Electrical New 10/4/2023 18:51 Low Noise detectors on Restart order Channel 2 Electrical New 10/4/2023 19:13 Low Noise detectors on Restart order Instruct 10/19/2023 15:53 Channel 2 Operator operator to Shutdown High Error pay attention to console Channel 2 Electrical New 11/28/2023 11:20 Low Noise detectors on Restart order

Idaho State University AGN-201m Reactor 2023 Annual Report Page 6 of 9

4. Safety Related Corrective Maintenance

Table III. Summary of Safety Related Corrective Maintenance (1 January 2023 through 31 December 2023)

Safety related Corrective Maintenance Date Performed Description 3/9/2023 FCR removed from core to try to alleviate squeaking noise. Upper bearing seems to be cause of noise. Bearing was ordered.

4/17/2023 All 4 rods removed and inspected after discovery of water on reactor skirt floor.

4/18/2027 Water on floor analyzed and beam ports removed while investigating source of water.

4/27/2023 Graphite blocks from thermal column were removed and inspected while investigating source of water on reactor skirt floor.

5/25/2023 Installed drip collection device to collect and redirect water leaking from reactor shield tank. (ISU-50.59-2023-2)

Investigation of magnets failing to energize when button was depressed 6/27/2023 is initiated. Problem traced to manual scram button not fully re-seating after button was pushed. Button was cleaned and returned to operational status.

Disconnected DAS from reactor by disconnecting the wires from the 9/20/2023 reactor console to the DAQ box due to discovery of abnormal indications when DAS computer was de-energized.

11/30/2023 SR 1 down fuse replaced after carriage failed to return to down after rod drop test.

Clamp on Channel 1 detector was adjusted after higher than normal 12/5/2023 count rate was noticed on channel 1. Count rate returned to normal after clamp adjustment.

5. Modifications

A. Changes in Facility Design - None

B. Changes to Procedures

Updates to Sub Critical Assembly Procedure to allow use of pen dosimeters was implemented.

C. Changes to Experiments - None

Idaho State University AGN-201m Reactor 2023 Annual Report Page 7 of 9

D. Reactor Safety Committee

As the end of the reporting period, membership of the Reactor Safety Committee (RSC) consisted of the following individuals:

Kermit Bunde - Chair (DOE-ID)

Mary Lou Dunzik-Gougar, PhD - Reactor Administrator (Assoc. Dean, ISU)

Kelly Zimmer (INL)

Larry Foulkrod - Reactor Supervisor in Training Mason Jaussi - Radiation Safety Officer Jay F. Kunze, PhD, PE, CHP (Emeritus Prof., ISU)

Benjamin Baker, PhD (INL)

Jason Andrus (INL)

6. Summary of Changes Subject to 10 CFR 50.59 Analyses

ISU-50.59-2023-2 reviews installing a water diverter to collect and divert water from above the control rods to a collection container.

7. Radioactive Effluents

A. Liquid Waste - tivityelea -

B. Gaseous Waste - l Estid vity Released

The AGN -201 Reacwas opeted for Wa -hours ave approxately 5 W as. At t -41 producggibleantiay low the efnt conceon lit gFR total acvity of Ar-eleasenvironmensrvaly estid a Ci using Equaon (2acvityoeeavitya gadioac eluent from the facy. A monthlymarycalculaous releaseiven in I

Table IV. Summary of Monthly Gaseous Radioactive Effluent Releases (1 January 2023 through 31 December 20 23)

Idaho State University AGN-201m Reactor 2023 Annual Report Page 8 of 9

(.)() ( )

() = (.) (2)

C. Solid Waste - Total Activity - None

8. Environmental Radiation survey

One environmental radiation surveys were completed in 2023, it was performed on 08/10/2023.

9. Radiation Exposure

The Radiation Safety Officer reviews personnel Radiation exposure quarterly. Annual reports of ionizing radiation doses are provided by the Radiation Safety Officer to all monitored personnel as specified in Section 15.4 of the ISU Radiation Safety Manual. Personnel are issued dosimeters by the Radiation Safety Department if they meet the criteria of Section 15.1 of the ISU Radiation Safety Manual. All monitored personnel were below dose limits for calendar year 2023

The 10 CFR 20.1201 occupational dose limits to adults are: total 5 rem, lens of eye 15 rem, shallow 50 rem, and deep 50 rem. The doses received for all reactor laboratory personnel during 2023 are well below the dose limits of 10 CFR 20.1201, and well below ISU ALARA limits (1 rem per year, 0.3 rem per quarter).

Idaho State University AGN-201m Reactor 2023 Annual Report Page 9 of 9

Table VI. Summary of Whole-Body Exposures to the Public (1 January 2023 through 31 December 2023)

None of the 188 visitors to the facility during 2023 received a measurable dose that would exceed the annual 0.1 rem dose limit of 10 CFR 20.1301 for members of the public.

Therefore, the average and maximum doses received by the personnel and the public are within NRC guidelines.

Report Prepared by:

Larry Foulkrod AGN-201m Reactor Supervisor in Training Completed: February 22, 2024

Reviewed and Approved by:

Larry Foulkrod Dr. Mary Lou Dunzik-Gougar AGN-201m Reactor Supervisor in Training AGN-201m Reactor Administrator Completed: February 22, 2024 Completed: