DDW-2024-010210

August 22, 2024
Jex Jensen
Pacificorp Huntington Plant
P.O. Box 680
Huntington, Utah 84528
Subject:Granted, Membrane Pilot Study Waiver, Huntington Well Treatment Plant (TP001);
Pacificorp Huntington Plant, System #08034, File #14824
Dear Jex Jensen:
On May 16, 2024, the Division of Drinking Water (the Division) received a request submitted by your consultant Easton Hopkins, EIT of Hansen, Allen, and Luce Engineers for a pilot study
waiver as allowed in Rule R309-530-8(5)(b). Review comments were sent back to your consultant on May 29, 2024. An updated pilot study waiver was received on August 15, 2024. According
to this rule, prior to design of a membrane filtration facility, a water supplier shall either complete a pilot test of a proposed membrane module or request and receive approval from
the Division to use comparable operational data from a full-scale membrane facility treating water of the same or similar quality for a proposed membrane module.
Samples from the Huntington Well Backup (WS002) were submitted for one-quarter of the required data outlined in R309-530-4(3)(c)(ii) and complete new source chemistries as outlined in
R309-530-4(3)(c)(i). The data was compared to the pilot studies for Mount Pleasant and Chandler, Arizona which used Toray membrane modules. Based on the data presented in the memo demonstrating
similar source water quality characteristics, the Division agrees that the operational data from the two water systems will be similar toPacificorp Huntington Plant and can be used in
the design and construction of a full-scale membrane treatment facility.
On this basis, the Division concurs with your request, and a pilot study waiver is granted for using the Toray membrane modules with the following conditions:
Pacificorp Huntington Plant will be required to submit the remaining three-quarters of data required in R309-530-4(3)(c)(ii) of the Huntington Well Backup (WS002).
Before submitting plans and specifications, a Preliminary Design Report must be submitted to the Division for review, based on the comparable operational data for Mount Pleasant and/or
Chandler, Arizona. The Preliminary Design Report must meet the requirements in R309-530-8(7)(a)(i-xi).
Once the Huntington Well (WS001) is active once again samples must be submitted as required by R309-530-4(3)(c)(i) and R309-530-4(3)(ii) for the water source before it can be treated
through the new membrane treatment plant.
Please maintain a copy of this letter with your permanent records for future reference.
If you have any questions regarding this pilot waiver, please contact Dani Zebelean, P.E., of this office, at [phone], or Michael Newberry, P.E., Permitting and Engineering Manager,
at [phone].
Sincerely,
Russell Seeley, P.E.
Assistant Director
DZ/mrn/mdbcc:Orion Rogers, Southeast Utah Health Department, [e-mail] Hopkins, Hansen, Allen, and Luce, [e-mail] Johnson, Hansen Allen, and Luce,
[e-mail] Jones, Hansen, Allen, and Luce, [e-mail]
Scarlet Lewis, Pacificorp Huntington Plant, [e-mail]
Bryan Wheeler, Pacificorp Huntington Plant, [e-mail]
Terry Guthrie, Pacificorp Huntington Plant, [e-mail]
Zachary Phelps, Pacificorp Huntington Plant, [e-mail]
Jex Jensen, Pacificorp Huntington Plant, [e-mail]
Dani Zebelean, P.E., Division of Drinking Water, [e-mail]
Sarah Page, PhD, Division of Drinking Water, [e-mail] Page, P.E, DEQ Southeast District, [e-mail]
DZebelean 08034 14824 Pilot Waiver Granted