DERR-2025-008678

October 8, 2025

Bridget Viletta
376 E. 400 S., Suite 120
Salt Lake City, UT 84111

RE: Well MW-1 Abandonment
Former Chicago Bridge and Iron Site

Dear Bridgett,

Anderson Engineering Company, Inc. (Anderson) has prepared this letter to document
the abandonment of one groundwater monitoring well associated with the former
Chicago Bridge and Iron site at 550 W. 1700 S., Salt Lake City, Utah.

Anderson mobilized to the site on September 24, 2025. Personnel identified the well to
be abandoned (MW-1), located in the south concrete entrance of the Jerry Seiner Kia
Dealership. The well casing was within a metal well vault approximately 6 inches below
the surface. MW-1 was subsequently abandoned according to UAC R655-4-14. The
well casing was filled with grout to a depth of six inches below the surface.
Approximately two inches of bentonite chips were placed above the grout. The
abandonment was completed with approximately four inches of concrete being placed
flush with the surrounding concrete. The work area was swept, cleaned, and isolated
with cones to prevent damage to the concrete seal.

A photo log of the site conditions and abandonment procedures is attached. Should you
have any questions or comments, please contact us at 801-972-6222.

Sincerely, Reviewed by:
ANDERSON Engineering Co. Inc.

Kevin B. Cosper, P.E. Ryan D. Eddy, P.E.
Principal | Environmental Team Lead Principal | President

Photo 1. View of the work area. Cones used for isolation of work area.

Photo 2. View inside at-grade well vault. Secondary well cap observed.

Photo 3. View inside secondary well cap. Well casing identified.

Photo 4. Cascade drillers mixing grout.

Photo 5. Cascade driller measuring depth to water and depth to bottom.

Photo 6. Cascade drillers pouring grout into well casing.

Photo 7. View of grouted well casing.

Photo 8. View of concrete cutter positioning over well vault.

Photo 9. View of well with vault removed.

Photo 10. View of poured concrete as left by Cascade Drilling.

Photo 11. View of completed concrete repair.