DSHW-2025-000905

February 13, 2025
Blake Downey
Wasatch Environmental, Inc.
2410 West California Ave.
Salt Lake City, Utah 84104
RE:Approval of the RevisedHuman Health Risk Assessment, Ecological Risk Assessment, and Indoor Air Sampling Report
Arms Technology Inc., East Shop1142 South 2475 West
Salt Lake City, UtahUTCA-0065
Dear Mr. Downey:
The Division of Waste Management and Radiation Control (Division) has completed its review of the revisedHuman Health Risk Assessment (HHRA), Ecological Risk Assessment (ERA), and Indoor
Air Sampling Report (Report)for the Arms Technology Inc. (ATI)East Shop submitted on February6, 2025, by Wasatch Environmental, Inc. (Wasatch) on behalf of ATI for the property located
at 1142 South 2475 West, Salt Lake City, Utah (Site).
The initial Report was submitted on December 4, 2024, and outlines the additional indoor air sampling performed to evaluate the efficacy of the sub-slab depressurization systems and
the results of a HHRA and ERA for a closure determination by the Division. The Division submitted commentson the Report (DSHW-2025-000203) dated January 13, 2025, and requested the comments
be addressed in a revised Report. After review, the Report adequately addresses all the Division’s comments.
An ERA waiver is granted by the Division because the Site 1.) is not a viable habitat, 2.) cannot be used by potential ecological receptors, and 3.) is heavily developed with no complete
or potentially complete exposure pathways in accordance with Utah Administrative Code R315-101-5(j)(3).
The HHRA indicates that cumulative risk for an industrial/commercial worker, excluding benzene and 1,2-dichloroethane which are not associated with the release and are from the manufacturing
process at the Site, is 1E-06 with a hazard index (HI) of 0.8. The HHRA also indicatesthe cumulative risk for a construction worker at the Site is 2E-05 with a HI of 115 which is within
the carcinogenic risk range of 1E-04 and 1E-06 but above the HI of 1 in accordance with Utah Admin. Code R315-101-7.
Based on the risk range identified at the Site, in accordance with Utah Admin. Code R315-101-8(e), land use controls outlined in a Site Management Plan (SMP) and Environmental Covenant
(EC) must be instituted to protectcurrent industrial/commercial workers and to prevent any future construction workers from residual contamination on-Site.The risk level for an industrial/commercial
worker at the Site is contingent upon maintainingthe depressurization systems as an engineering control. Additionally, administrative controls should be put in place to protect future
construction workers from impacted groundwater, soil, and soil vapor. Therefore, the Division has determined that a Corrective Action Complete with Controls may be granted.
Please submit an SMP and EC to the Division for review by April 21, 2025.
The Division has no questions or concerns regarding the Report. The Report is hereby approved.
If you have any questions, please call Ethan Uptonat [phone].
Sincerely,
Douglas J. Hansen, Director
Division of Waste Management and Radiation Control
DJH/EAU/
Enclosures:
c:Dorothy Adams, Health Officer, Salt Lake County Health Dept.
Eric Peterson, Deputy Health Officer, Salt Lake County Health Dept.
Ron Lund, Environmental Health Director, Salt Lake County Health Dept.
Blake Downey, Wasatch Environmental, Inc. [e-mail]