DRC-2025-002846

September 2, 2025
Vern C. Rogers, Director of Regulatory Affairs
EnergySolutions, LLC
299 South Main Street, Suite 1700
Salt Lake City, UT 84111
RE:Federal Cell Facility Application Request for Information
Dear Mr. Rogers:
The Division of Waste Management and Radiation Control (Division) hereby provides follow up Requests for Information (RFI) regarding the Federal Cell Facility Application dated August
4, 2022.
Each RFI in the attached document represents a follow up to an RFI issued earlier in the application review process. The numbering system ties the additional questions to the initial
RFI with an added letter designation. When responding to an RFI, please use the assigned number representing the question.
With this round of follow up RFIs, the Division recommends that appropriate staff from the Licensee, the Division and consultants meet to discuss each matter for clarity. Please contact
Larry Kellum at 385-622-1876 to schedule a meeting.
Sincerely,
Douglas J. Hansen, Director
Division of Waste Management and Radiation Control
DJH/LK/JMK/BBD
Enclosure: Federal Cell Application, Requests for Information.
c:Jeff Coombs, EHS, Health Officer, Tooele County Health Department
Bryan Slade, Environmental Health Director, Tooele County Health Department EnergySolutions General Correspondence EmailLLRW General Correspondence Email
Federal Cell Application Review
Request for Information or Updates to the Application (RFI)
General
Each of the RFI’s has been assigned an identifier with a numbering convention as follows-
Application/Appendix Section
Section/Appendix Subsection
Section/Appendix Subsubsection (when applicable)
Sequential numbering
Example: A question in Section 1, subsection 1, subsubsection 1 -The first RFI # would be 1.1.1-1, the next question in that section/subsection would be numbered 1.1.1-2
Please refer to the assigned RFI number when submitting a response.
Appendix O: Federal Cell Facility Waste Characterization Plan
O-40.d-1
The response to RFIO-40.d states that the deep aquifer (Unit 1) was excluded from the Performance Assessment due to a natural upward gradient. However, excluding Unit 1 from the model
would result in an incomplete/inaccurate representation of the shallow aquifer due to its direct influence as a recharge source on the aquifer's geochemical properties.Additionally,
the response indicatesthat “minerology is not relevant to the model and so is removed". While Unit 1 is acknowledgedby previous sources (i.e., BinghamEnvironmental 1991-1996) as having
high clay content, it is not adequately characterized. Theinterbedded nature of Unit 1 indicates mineralogicalheterogeneity, which could suggest preferential flow paths through sandy
layers. Generally, a geochemical model's uncertainty regarding radionuclide sorption will increase without mineralogical data, making it difficult to accurately predict the effects of
changes in water chemistry.
Please provide additional clarification on the rationale for excluding Unit 1 from the model.
O-40.e-1
The response to RFI O-40.e provided a detailed response regarding the approach and methodology of the selection of distributing coefficient (Kd) values using a broad range of literature
values for units 2,3, and 4. The minerology of the soil types of Hydrostratigraphic Units 1-4, has a crucial role in the partitioning coefficient, as different clay minerals, oxides
and sands have varying structures, ion exchange capacities, and surface areas which can significantly impact Kd values and contaminant mobility. The response states that “Kd input values
are not easily obtained for the Clive site". However, they can be better estimated based on minerology. The Distribution Coefficient (Kd) is an empirical parameter and is highly dependent
on the geochemical environment, which includes its minerology, solubility and sorption processes.Please provide a detailed evaluation of the minerology of hydrostratigraphic units 1-4
that includes a comparison of the partitioning coefficients to the site specific conditions.