ML24349A003

University of Utah - Exemption Request Supplementation Information for December 13th, 2024

ML24349A003
Person / Time
Site:	University of Utah
Issue date:	12/13/2024
From:	Allison A Univ of Utah
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
Download: ML24349A003 (1)

Text

1 NUCLEAR REGULATORY COMMISSION Docket No. 50-407 University of Utah TRIGA Reactor Exemption Request Supplemental Information for December 13th, 2024 The University of Utah TRIGA Reactor (UUTR) is currently in a shutdown/secured state pending necessary repairs to the reactor tank, and it is not expected to return to operation until Fall, 2025.

UUTR requests to amend the original exemption request outlined by letter dated June 17, 2024 (Agencywide Documents Access and Management System Accession No. ML24183A173), and supplemented by letter dated September 5, 2024 (ML24250A104) as follows:

1) Extend expiration date of exemption request until December 31st, 2025 based on the following updated schedule:

February 2025: establish repair contract with suitable engineering firm March-April 2025: Inspect tank and develop repair plan May-June 2025: Repair tank based on inspection results July - September 2025: Reconstruct reactor inside repaired tank October 2025: Perform reactor maintenance November - December 2025: Additional time to account for probable delays

2) Remove Jesse Snow (RO-505180) from consideration for this exemption request.

UUTR intends to restore reactor operations using only Edward Goodell and Andrew Allison performing licensed duties as SRO/RO.

3) UUTR is providing the following supplemental information to the NRC for consideration of our exemption request in response to NRC Acceptance of Requested Licensing Action letter for University of Utah dated November 5th, 2024 (ML24303A345):

1. The NRC requests that you provide the date of the most recent annual operating exam per 10 CFR 55.59(a)(2) which was completed for Andrew Allison, Edward Goodell, and Jesse Snow.

Andrew Allison completed his most recent annual operating exam on September 5th, 2023. Edward Goodell completed his most recent annual operating exam on November 17th, 2022 as a Reactor Operator, but was relicensed as an SRO upgrade on March 27th, 2023. Jesse has not performed an annual operating exam since his RO licensing on March 27th, 2023. Of note, we are canceling the application of this exemption request for Jesse Snow as reactor operator.

2. Request clarification on when the annual operating exam will be performed following expiration of the exemption.

The purpose of this exemption request is to enable UUTR staff to restore the reactor to full operational capability. Unless an extension to this exemption is required because of further maintenance delays, Andrew Allison and Edward Goodell intend to perform their annual operating exams after successful completion of all restoration maintenance and prior to the requested

2 expiration date of December 31st, 2025. Following the expiration of the exemption, all UUTR staff intend to be in full compliance with 10 CFR 55 regulatory requirements going forward.

3. In your application, you proposed that licensed operators will receive special refresher training, but did not describe this training and how it differs from the training in the NRC approved requalification plan. Provide information regarding:

a. Periodicity of the special refresher training.

The special refresher training will take place once during 2025. Of note, UUTR intends to complete its annual lecture-based training, per the approved requalification plan, during Spring 2025.

b. Description of the special refresher training activities and objectives.

The objective of the special refresher training is to refamiliarize Andrew Allison and Edward Goodell with reactor controls and response associated with a TRIGA reactor. It will involve 2 key activities:

1) Operation of a reactor simulator that replicates our digital human-machine interface and simulates point-kinetic reactor physics for UUTR. This simulator will be used to replicate a reactor startup, power range manipulations greater than 10kW, and shutdown. Of note, this simulator is not an NRC approved simulator for practical factors associated with an annual operating examination. Furthermore, UUTR does not interpret approval of this exemption as approval from the NRC for any practical factors associated with reactor operations or examination. The simulator is currently only used for training and demonstration purposes.

2) Power manipulations at a similar research reactor such Reed Research Reactor as described in the following section. These manipulations will involve Andrew Allison and Edward Goodell performing a reactor startup, power range manipulations greater than 30kW, and shutdown.

Following completion of this special refresher training, UUTR staff will submit a letter in accordance with 10 CFR 55.59(b) to the NRC stating its successful completion and UUTRs intentions to complete restoration of the UUTR and maintenance requiring an operable reactor. Based on recent experience with fuel transfers during the summer of 2024 and fuel inspection of 2023, Andrew Allison and Edward Goodell intend to move and inspect fuel without requiring the activities associated with this special refresher training.

4. Provide information regarding the proposed training to be conducted at another facility:

a. Which operator(s) will receive training at another facility.

Edward Goodell and Andrew Allison will receive the training at another facility.

b. Which items from 10 CFR 55.45(a) will be performed at the alternate facility.

Andrew Allison and Edward Goodell will perform the following items from 10 CFR 55.45(a) because they cannot be performed at UUTR:

(2) Manipulate the console controls as required to operate the facility between shutdown and designated power levels.

(5) Observe and safely control the operating behavior characteristics of the facility.

3 (6) Perform control manipulations required to obtain desired operating results during normal, abnormal, and emergency situations.

c. Justification describing why the Reed College reactor facility (or the Oregon State University reactor facility as an alternate to Reed College) are suitable for providing training of operators licensed at the Utah reactor facility. Include discussion on a comparison of the alternate reactor facilities with the University of Utah that supports the appropriateness for the specified training activity. Comparisons should address reactor design, console design and reactivity response, etc.

Reactor Design Comparison: UUTR and Reed Reactor (RRR) are both water-moderated, water-cooled thermal reactors operated in an open below-ground construction pool. Both reactors are controlled by three Boron carbide control rods that display rod position indication as a percentage of total travel via a 10-turn potentiometer. UUTR features a hexagonal core containing 78 aluminum/stainless-steel cladding fuel elements with 3 control rods located in the D ring. RRR has a cylindrical design of 80 stainless-steel fuel elements with 2 control rods located in the C ring and a regulating rod in the E-ring.

Both UUTR and RRR use a compensated ion chamber to provide indication of power from 0 to 120%

over 9 linear ranges of power. Both UUTR and RRR have high power scrams attached to signals provided by the uncompensated ion chamber and compensated ion chamber. Both UUTR and RRR use a fission chamber with a neutron flux monitor to monitor power in the source range. See Table 1 for an explanation of the differences in power display provided by reactor instrumentation.

Console Design Comparison: Both consoles contain the same interlocks to prevent simultaneous rod withdraw of more than one control rod and rod withdraw on low source counts. Both consoles are controlled by a raise and lower button for each control rod along and have indications activated by limit switches for when each control rod is at the top or bottom of travel. Both consoles provide a digital chart recorder to display reactor power and have reactor power displays from the three instruments prominently in front of the operator. Both consoles display tank water level and Continuous Air Monitor readings from the console. Both facilities have a similar ventilation system with an indication at console to show ventilation system status. See Table 1 for an explanation of the differences between the consoles to include power display provided by reactor instrumentation and reactor scrams.

Reactivity Response: A key difference between UUTR and RRR is the reactivity response from the control rods. All UUTR Control Rods move at approximately 11 inches/minute. RRR control rods vary in speed: 11 inches/minute for the shim rod, 19 inches/minute for the safety rod, and 24 inches/minute for the regulating rod. A faster control rod speed combined with a higher reactivity worth per control rod results in a faster reactivity insertion rate at RRR. RRR also has an automatic control feature for their regulating control rod. Of note, to better simulate UUTR reactor, UUTR operators will not use the automatic control option of RRR for their operating examination.

4 Table 1: Summary of Key Differences Characteristic UUTR RRR Reactor design Hexagonal design for 126 element holders up to G ring Circular design consisting of 90 element holders up to F ring Power Limit 100kW 250kW Uncompensated ion chamber (percent channel) range 0.001 to 150%

0 to 100%

Control Console Digital Displays relayed from Analog instrumentation drawers Analog Displays Control Rod Speed 11 inches/minute for all rods Shim: 11 inches/minute Safety: 19 inches/minute Regulating: 24 inches/minute Control Rod Worth Safety: $2.00 Shim: $1.5 Regulating: $0.40 Safety: $2.19 Shim: $2.78 Regulating: $1.19 Fuel Temperature Display C-ring and D-ring instrumented fuel element display none Shutdown Margin

$0.50

$0.50 Excess Reactivity

$1.20

$3.00 Reactor Scrams UUTR has the same scrams as RRR with 4 additional scrams as well:

low pool water level, high fuel temperature, magnetic key scram, scram on loss of power.

High power scram (percent channel)

High power scram (linear channel)

Manual Scram button Water specification display pH, conductivity, and 4 channels of water temperature displayed on console.

Contains one display for tank water. No pH indication.

Conductivty is viewed from another room Coolant system Primarily operated from control room.

Primarily operated from reactor bay. Emergency shutoff from control room Area Radiation Monitors (ARM)

Console displays readings from 4 ARMs throughout the facility.

Contains 1 reading displayed in reactor room, but visible from console.

5. Provide a justification for how granting this exemption will not endanger life or property.

The exemption would allow two senior operators at the facility who do not satisfy the requalification requirements of 10 CFR 55.53(h) and 10 CFR 55.59(a) and the active performance requirements of 10 CFR 55.53(e) and (f) to continue to perform the functions of a senior operator to support the resumption of fuel maintenance activities and the return of the facility to normal operations. 10 CFR 55.11 allows the Commission to grant exemptions from the requirements of 10 CFR part 55, including 10 CFR 55.53(e), (f), and (h) and 10 CFR 55.59(a), when they will not endanger life or property. The requested exemption will not endanger life or property because it would allow persons experienced with licensed activities involving fuel maintenance to resume fuel inspection

5 and restart the reactor. These activities would be performed consistent with the facilitys Commission-approved technical specifications and would, therefore, ensure that the necessary quality of systems and components is maintained.

Further, the requested exemption will not endanger life or property because UUTR will provide additional training for the two senior operators that would provide reasonable assurance of their competence as senior operators regarding facility operations equivalent to that required by the NRCs regulations and because that additional training would be required by the NRC, pursuant to 10 CFR 55.59(b), including the submission of evidence to the Commission of the successful completion of the training, before the facility is returned to normal operations. The UUTR Requalification Plan will continue to be used, and supplemented, for items that can be completed at the facility, such as through training, lectures, and written examinations. The items in the plan that cannot be completed at the facility, such as control manipulations, would be accomplished at RRR to satisfy the operating test requalification requirements of 10 CFR 55.45(a)(2), (5), and (6).

6. Provide a justification for why this exemption is in the best interest of the public.

The exemption would allow two senior operators at the facility who do not satisfy the requalification requirements of 10 CFR 55.53(h) and 10 CFR 55.59(a) and the active performance requirements of 10 CFR 55.53(e) and (f) to continue to perform the functions of a senior operator to support the resumption of fuel maintenance activities and the return of the facility to normal operations. As stated above, 10 CFR 55.11 allows the Commission to grant exemptions from the requirements of 10 CFR part 55, including 10 CFR 55.53(e), (f), and (h) and 10 CFR 55.59(a), when they are otherwise in the public interest. The Commissions values guide the NRC in maintaining certain principles of good regulation as it carries out regulatory activities in furtherance of its safety and security mission. These principles focus the NRC on ensuring safety and security while appropriately considering the interests of the NRCs stakeholders, including the public and licensees. The NRCs principles of good regulation can also provide guidance as to whether the granting of a particular exemption is otherwise in the public interest.

On balance, the NRCs principles of good regulation demonstrate that the granting of the requested exemption is otherwise in the public interest. The scope of the exemption is limited to resuming fuel maintenance activities and returning the facility to normal operations. The two senior operators would be allowed to resume fuel maintenance activities, including fuel transfers and inspections, upon the issuance of the exemption; however, pursuant to 10 CFR 55.59(b),

the senior operators would be required to complete the additional training discussed above and to submit evidence to the Commission of the successful completion of this training before returning the facility to normal operations. As discussed above, this would ensure that the senior operators have the competence required to perform these duties. Moreover, the exemption would expire on December 31st, 2025. After this time, the senior operators would again be fully subject to the regulations related to the NRCs requalification and active performance requirements. Thus, the exemption is narrowly tailored and does not make any permanent changes to the senior operator licenses, the facility license, or UUTR programs. This approach provides for an efficient and clear resolution to a situation that is outside of the considerations of the applicable regulations.

6 I declare under penalty of perjury that the foregoing is true and correct. UUTR requests the Commission issuance of exemption no later than March 15th, 2025 for UUTR to continue with restoration of the reactor tank.

Andrew Allison December 13th, 2024_________

Andrew Allison, UUTR Interim Director Date