ML24267A253
| ML24267A253 | |
| Person / Time | |
|---|---|
| Site: | Abilene Christian University |
| Issue date: | 09/27/2024 |
| From: | Rivera R NRC/NRR/DANU/UAL2 |
| To: | Stephen Philpott Office of Nuclear Reactor Regulation |
| References | |
| EPID L-2024-NFO-0005 | |
| Download: ML24267A253 (1) | |
Text
MEMORANDUM TO:
Stephen Philpott, Acting Chief Advanced Reactor Licensing Branch 2 Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation FROM:
Richard Rivera, Project Manager Advanced Reactor Licensing Branch 2 Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF THE AUGUST 20, 2024, PARTIALLY CLOSED MEETING WITH ABILENE CHRISTIAN UNIVERSITY (ACU),
PUBLIC MEETING: MOLTEN SALT RESEARCH REACTOR (MSRR) MATERIAL CONTROL & ACCOUNTING WHITE PAPER REVIEW (EPID NO.: L-2024-NFO-0005)
Meeting Information:
Sponsor: Abilene Christian University Docket No.: 05000610 Public Meeting Notice Agencywide Documents Access and Management System (ADAMS)
Accession No.: ML24220A269 Meeting Attendees: See the enclosure for a list of meeting attendees.
CONTACT: Michelle Vega Rodriguez, NRR/DANU/UAL2 301-415-1170 September 27, 2024 Signed by Rivera, Richard on 09/27/24
S. Philpott Meeting Summary:
The U.S. Nuclear Regulatory Commission (NRC) staff conducted the meeting in accordance with NRC Management Directive 3.5, Attendance at NRC Staff-Sponsored Meetings (ML21180A271). The table below includes a summary of the main points of discussion during the meeting.
NRC Questions ACU Responses 1.
To the extent possible, please provide a general overview of the nuclear material flows for the facility.
Fuel form and fuel shipping is still being discussed in ACU.
ACU assumes that the fuel will be shipped from the Department of Energy (DOE) in a UF4 form.
Upon receipt, the fuel will be located in the Science and Engineering Research Center (SERC) bay area.
The fuel will be quantified to verify the shipping information from DOE (quantity and composition).
o This information will depend on the DOE shipping information rather than ACUs quantification.
ACU will transport the fuel, when needed, to the Fuel Handling System (FHS), which will add it to the reactor.
o Once added to the reactor, the fuel is expected to remain there until determined by ACU.
o Significant burnup of fuel is not expected.
o All fuel samples will be quantified upon removal and stored in a controlled manner.
The vast majority of the fuel will stay within the reactor for the life of the reactor.
o Minor additions of fuel are expected for reactivity control purposes.
After use, the fuel will be prepared to be returned to the DOE, which will keep ownership of the fuel thereafter.
The fuel will stay in liquid form while the reactor is operating.
2.
On page 6, ACU lists the projected material mass at Beginning of Life (BOL) and End of Life (EOL).
The mass at BOL is expected to be the mass of the fuel within the reactor.
BOL is defined as the first day that the reactor will be loaded with fuel and
S. Philpott a.
Is this just inventory in the reactor systems or does it include any fuel storage? What does BOL and EOL mean in the context of this MSRR?
b.
The NRC staff notes that the amount of U and U-235 does not change from BOL to EOL. Given that there will be some nuclear loss, is the EOL number including additions of UF4?
c.
The NRC staff notes that the EOL Pu element is all Pu-239 isotope.
Given that the initial uranium enrichment is about 16% U235, will other isotopes of Pu be present?
goes critical.
EOL is defined as the moment when the reactor is shut down and the fuel is prepared to be returned to the DOE.
The MSRR is designed for 5 years of full power operation (5 megawatt-years).
ACU does not expect to come close to a full power level of operation.
Initially, the reactor will have a very low burnup rate as the reactivity control and other parameters are analyzed.
Follow up items from the NRC staff:
What happens if fuel is needed during operation? How is that accounted for?
o The MSRR has the capability to add fuel to account for small burnup amounts through the FHS.
There is a gas cavity at the top of the vessel that allows the addition of UF4 to account for burnup throughout the operation of the reactor.
o Fuel additions will depend on the power history of the reactor.
o ACU is still working on the specific details for this process.
The amount of U-235 does not change through the life of the reactor o
The burnup rate is expected to be very small; changes may be at the six significant digits level.
Pu-239 and U-235 are the transuranic products that ACU has been focusing on.
o There may be other Pu isotopes produced in the MSRR.
o ACU can provide the information on all other Pu isotopes.
o In the white paper, ACU only those isotopes that it considered to be of interest to the NRC staff.
3.
On page 9, general provisions for the physical inventory are outlined. The NRC For physical inventory purposes, ACU is planning to quantify at BOL and
S. Philpott staff realize that this is all preliminary information and still under development.
a.
Is it anticipated that the physical inventory will be performed with the reactor operating or shutdown?
b.
While the reactor is operating, is some amount of material in the drain tank?
c.
When you drain the tank, would you have salt in the tank?
d.
Can the physical inventory be performed sometimes with the reactor shutdown and the total process material contents in the drain tank (minus any holdup)?
EOL, and maintain control of the material in between.
ACU does not plan to quantify the composition of the fuel on a routine basis.
The NRC staff is interested in the calculations of the mass and composition of U, when the reactor is shutdown.
ACU will be able to quantify the material through a level gauge, rather than through chemical composition analysis. Other methods (to be specified) will be applied to determine that the expected amount of material is always present.
ACU plans to use the drain tank to quantify the material through the use of gauges.
Only minimal residual amounts of fuel may remain in the drain tank. The vast majority of the fuel will be contained in the reactor vessel.
4.
How often do you estimate that UF4 will be added to the fuel salt to maintain reactivity and how much?
It depends, ACU anticipates that at BOL, operations will be at very low power level, mostly for experiments and other activities. At that level, ACU does not expect the need for additions of fuel.
At a higher power level, there may be a need to add small amounts of fuel to account for burnup.
S. Philpott Public Comments Portion:
Members of the public expressed interest in knowing if this reactor will follow the regulations in Title 10 of the Code of Federal Regulations Part 74, Material Control and Accounting of Special Nuclear Material, Subpart D, Special Nuclear Material of Low Strategic Significance.
Given the preliminary nature of the information regarding the MSRR that is available, the NRC staff from the Office of Nuclear Material Safety & Safeguards (NMSS) is analyzing how to address some of the material control and accounting aspects of concern to ACU.
NMSS is also exploring additional security considerations based on the amount of special nuclear material that may apply to ACU.
Members of the public also expressed concerns related to the amount of active nuclear material that could be of interest to adversaries and directly applied to weapons.
No regulatory decisions were made as a result of this meeting.
Docket No.: 05000610
Enclosure:
List of Attendees cc: Abilene Christian University via GovDelivery
S. Philpott
SUBJECT:
SUMMARY
OF THE AUGUST 20, 2024, PARTIALLY CLOSED MEETING WITH ABILENE CHRISTIAN UNIVERSITY (ACU), PUBLIC MEETING: MOLTEN SALT RESEARCH REACTOR MATERIAL CONTROL & ACCOUNTING WHITE PAPER REVIEW (EPID NO.: L-2024-NFO-0005)
DATED: SEPTEMBER 27, 2024 DISTRIBUTION:
PUBLIC UAL2 R/F MVega Rodriguez, NRR RRivera, NRR CSmith, NRR DJackson, NMSS EHelvenston, NRR GTuttle, NMSS JTokey, RES JRussell, NMSS SAni, NMSS RidsNrrDanuUal1 Resource RidsNrrDanuUal2 Resource RidsNrrDanu Resource ADAMS Accession Number: ML24267A253 NRC-001 OFFICE NRR/DANU/UAL2:PM NRR/DANU/UAL2:PM NRR/DANU/UAL2:LA NAME MVega Rodriguez RRivera CSmith DATE 9/23/2024 9/24/2024 09/24/2024 OFFICE NRR/DANU/UAL2:BC (A)
NRR/DANU/UAL2:PM NAME SPhilpott RRivera DATE 9/26/2024 9/27/2024 OFFICIAL RECORD COPY
Enclosure LIST OF MEETING ATTENDEES PARTIALLY CLOSED MEETING WITH ABILENE CHRISTIAN UNIVERSITY, PUBLIC MEETING: MOLTEN SALT RESEARCH REACTOR MATERIAL CONTROL & ACCOUNTING WHITE PAPER REVIEW AUGUST 20, 2024 Name Organization Diane Jackson U.S. Nuclear Regulatory Commission (NRC)
Edward Helvenston NRC Glenn Tuttle NRC Jason Tokey NRC John Russell NRC Michelle Vega Rodriguez NRC Richard Rivera NRC Suzanne Ani NRC Benjamin Beasley Abilene Christian University (ACU)
Cori Shoultz ACU Kim Pamplin ACU Lester Towell ACU Tim Head ACU Steven Biegalski Georgia Institute of Technology (GT)
Riley J. Fecker GT Joy Jiang Member of the public Spencer Toohill Member of the public Edwin Lyman Member of the public