DDW-2025-005617

195 North 1950 West • Salt Lake City, UT Mailing Address: P.O. Box 144830 • Salt Lake City, UT 84114-4830 Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov Printed on 100% recycled paper
State of Utah

SPENCER J. COX Governor DEIDRE HENDERSON Lieutenant Governor
Department of Environmental Quality
Tim Davis Executive Director DIVISION OF DRINKING WATER Nathan Lunstad, Ph.D., P.E. Director
May 20, 2025

Jon Finlinson Intermountain Power Service Corp 850 W Brush Wellman Rd Delta, UT 84624
Subject: Notice of Decreased Monitoring for Intermountain Power Service Corp, UTAH14050
Jon Finlinson: This letter serves as notification that monthly monitoring for arsenic is no longer required from the Arsenic Water Treatment Plant (identified as TP003). One arsenic sample collected from the Arsenic Water Treatment Plant (TP003) is now required each quarter. The next arsenic sample is
due sometime between April 1, 2025 and June 30, 2025. A monthly arsenic sample requirement was assigned to the Arsenic Water Treatment Plant (TP003) in April 2022. Throughout 2023 and 2024 there were no sample results in excess of the arsenic maximum contaminant level (MCL) of 0.010mg/L. This facility qualifies for reduced
monitoring pursuant to R309-205-5. The updated source chemical monitoring requirements for the Arsenic Water Treatment Plant (TP003) are given below and are available to view anytime on waterlink.utah.gov. Please contact David Kruse at [e-mail] or 385-566-7789 for questions regarding the source chemical
monitoring requirements for this system.
Facility with new requirements Analyte(s) Required # Of samples Sampling Frequency Next Due Date Rule Reference
TP001 Arsenic
Treatment Plant Arsenic 1 Quarterly 04/01/2025-
06/30/2025
R309-215-
6(2)(a)

Jon Finlinson Page 2 of 2
May 20, 2025
Sincerely,
Mark Berger
Monitoring and Standards Implementation Manager
Enclosure – Monitoring Schedule cc: John Finlinson, Intermountain Service Corp, [e-mail] Eric Larsen, Central Utah Health Department, [e-mail] John Chartier P.E., DEQ District Engineer, [e-mail] Mark Berger, Division of Drinking Water, [e-mail] David Kruse, Division of Drinking Water, [e-mail]