STATE ENGINEER’S OFFICE
PRELIMINARY OPINION
OF THE

WATER SUPPLY AND WATER YIELD ANALYSIS

FOR

PROJECT WEST‐WEST SODA LLC, SWEETWATER COUNTY, WYOMING

OCTOBER 2023

The State Engineer’s Office/Surface Water Division completed a comprehensive review of the
Water Supply and Yield Analysis Report submitted by WWC Engineering on behalf of West Soda
LLC (“West Soda”) for the proposed Project West Facility (“the Project”) in Sweetwater County,
Wyoming.

WWC Engineering estimates the Project will require a maximum of approximately 4,922.97 acre-
feet of water per year, which is equivalent to a continuous diversion of 6.80 cubic feet per second

(“cfs”). The projected life of the mine is 25-35 years with an additional two years for construction
and two to four years for reclamation. However, if additional mineral leases are acquired by West
Soda in the future, the mine could run for 75 years with a potential for longer operation based on
mine expansions in the future. West Soda LLC proposes providing the water supply for the Project
through the following mechanisms:

● Water will be diverted from the Green River through the Project West Green River Intake
(Permit No. 36889) located in Lot 6 of Section 7, T18N, R107W or through temporary water haul
permits prior to completion of the pipeline.
● West Soda will contract for 8,000 acre-feet of water stored in Fontenelle Reservoir to use
in the event that water is not available under Permit No. 36889 or temporary water haul permits
due to an intrastate or interstate regulation event.
● In the event that the 8,000 acre-feet of contracted water in Fontenelle Reservoir is not
available as a backup, West Soda will pursue temporary water use agreements or water right
exchanges for its water supply.
● There are twenty (20) groundwater monitoring wells that will be installed in the solution
mining area. Water generated during well drilling and sampling will be beneficially used for dust
abatement under current miscellaneous use permits located in Sections 5, 9, 13, and 15 of T16N,
R110W.

In summary, it is the opinion of the State Engineer’s Office that a sufficient quantity of water for
the Project has been adequately resourced and that the Project should proceed with development
of the Project West Green River Intake, and with acquiring other necessary permits to allow the
Project to go forward.

The Project West Water Supply and Yield Analysis Report (October 2023) and the State
Engineer’s Preliminary Opinion (December 2023) in its entirety, are available on the State
Engineer’s Office website @ https://seo.wyo.gov/home/news-press-releases

 

Pursuant to W.S. 35-12-108, the State Engineer’s Office will accept written comments on the
Preliminary Opinion through midnight, January 17, 2024. Comments can be submitted to:
State Engineer’s Office/Surface Water Division, 122 West 25th Street, Herschler Building, 2W,
Cheyenne, WY 82002; or to [email protected]

In accordance with the Americans with Disabilities Act, special assistance or alternative formats
will be available upon request for individuals with disabilities.