DDW-2025-005966

July 2, 2025
Sent via Email Only
Christopher Robinson
Oquirrh Mountain Water Company
7780 North Buckhorn Road
Stansbury Park, Utah 84074
[e-mail]:Operating Permit, Hole in the Rock #2 Well (WS008), Hole in Rock #2 Well Chlorinator (TP003); Oquirrh Mountain Water Company,System #23076, File #15783
Dear Christopher Robinson:The Division of Drinking Water (the Division) received your request for the Operating Permit for Hole in the Rock #2 Well (WS008) and Hole in the Rock #2 Well
Chlorinator (TP003) from your consultant, Jacob Nielsen and Hansen Allen and Luce Engineers on May 30, 2025. The Division issued After-the-Fact (ATF) Plan Approval for drilling the Hole
in the Rock #2 Well (WS008) on May 5, 2022, File #12942 and Plan Approval for equipping this well on September 24, 2024. This project has met all the conditions for receiving an operating
permit.
Our understanding of the project was the drilling of a 16-inch diameter production well to a depth of 1,025 feet. The installation of a 1,400-gpm vertical turbine pump, 250 hp motor.
Construction of a new well house and associated valving and piping, along with the installation of a new gaseous chlorinator. These facilities are identified as (WS008) and (TP003) in
the Division’s database.
The Hole in the Rock #2 Well Chlorinator (TP003)included in this project has been completed according to the following:
The Hole in the Rock #2 Well Chlorinator is a gas chlorinator Model Evoqua / Wallace & Tiernan S10K Sonic Chlorinator, with a Model CR 1s-4 Grundfos chlorine booster pump to provide
secondary disinfection.
The Hole in the Rock #2 Well Chlorinator treats water from the Hole in the Rock #2 Well (WS008).
The chlorinated water then flows into the distribution system.
The gaseous chlorine used for disinfection meets the ANSI/NSF 60 standard.
A design target dose of 0.2 mg/L (ppm) of free chlorine is based on a typical flow of 1,400 gallons per minute (gpm) from Hole in the Rock #2 Well.
The chlorine dose is adjusted by an automatic flow-paced control.
We have received the following information for Hole in the Rock #2 Well (WS008), Hole in the Rock #2 Well Chlorinator (TP003):
Certification of Rule Conformance with plan approval conditions by a professional engineer
As-built or record drawings.
Satisfactory bacteriological results as evidence of proper disinfection and flushing.
Evidence of operation and maintenance manual delivery.
We have determined that all conditions for issuing an operating permit have been met. On this basis, an Operating Permit for Hole in the Rock 2 Well and Hole in the Rock #2 Well Chlorinatoris
hereby issued as constituted by this letter. You may now place Hole in the Rock #2 Well and Hole in the Rock #2 Well Chlorinator in service in your water system.
Please maintain a copy of this letter with your permanent records for future reference.
Secondary Disinfection Requirements
The Oquirrh Mountain Water Company is not required to disinfect the Hole in the Rock #2 Well (WS008) based on bacteriological source sample results currently available. The water systemhas
voluntarily installed the Hole in the Rock #2 Well Chlorinator (TP003) to provide a detectable disinfectant residual in the distribution system for secondary disinfection.
Please be aware that if any water source of the Oquirrh Mountain Water Companyis found to require primary disinfection in the future per R309-200-5(7)(a)(i), additional regulations will
apply. This will include submitting disinfection CT information showing compliance with 4-log virus inactivation in accordance with the Ground Water Rule in R309-215-16.
The Oquirrh Mountain Water Company is required to demonstrate ongoing compliance with the secondary disinfection requirements outlined in Addendum 1 of this letter as long as the Hole
in the Rock #2 Well Chlorinator (TP003) is in operation.
Monitoring and ReportingIssuance of this Operating Permit changes your water system’s monitoring and reporting requirements. Please see addendum 1 for a detailed explanation of the changes
to this system's monitoring and reporting requirements. Please contact Mark Berger, Water Quality/Monitoring and Standards Manager at [phone] for questions regarding the monitoring
and reporting requirements for your water system.
There may be new changes in monitoring and reporting requirements in the future as the Division continues to improve the disinfection monitoring and reporting practices. Failure to adhere
to required monitoring and reporting will result in violations and the assessment of IPS points.
If you have any questions regarding this Operating Permit, please contact Brent Arns, of this office, at [phone], or Michael Newberry, Permitting and Engineering Support Manager,
at [phone].
Sincerely,
Russell Seeley, P.E.
Assistant Director
BA/mrn/mdbcc:Bryan Slade, Tooele County Health Department, [e-mail] Robinson, Oquirrh Mountain Water System, [e-mail] Nielsen,
Hansen, Allen & Luce, [e-mail] Treutel, Division of Drinking Water, [e-mail] Kruse, Division of Drinking Water, [e-mail] Martinez, Division
of Drinking Water, [e-mail] Yee, Division of Drinking Water, [e-mail] Payne, P.E., Division of Drinking Water, [e-mail] Noble, P.G., Division
of Drinking Water, [e-mail] Martin, P.E., Division of Drinking Water, [e-mail] Arns, Division of Drinking Water, [e-mail] Steffan, Division of Drinking
Water, [e-mail] 23076 15783 OP Hole in the Rock Well (WS008) Chlorinator (TP003)
Addendum 1 - Updated Monitoring and Reporting Requirements
Elective Monitoring and Reporting Requirements 
Chlorine Monitoring & Reporting Requirements
The water system is required to meet elective disinfection requirements. As a part of these requirements, the water system is required to continuously maintain a minimum free chlorine
residual at each chlorinator Point of Entry (POE) into the system and demonstrate a detectable chlorine residual in the distribution system. 
Elective Disinfection Requirements and Reporting 
Chlorine Residual ‒ Point of Entry (POE) to Distribution System

The POE sampling location is identified as EP003 in the Division’s database. This location has been identified as the sample tap after the storage tank. Maintain a minimum of 0.2 mg/L
residual (measured as free chlorine) at the POE sampling location. [R309-215-16(3)(b)(iii)(A)(I) and (II)]
The chlorine residual concentration measured at the POE sampling location shall not exceed the maximum residual disinfectant level (MRDL) of 4.0 mg/L (measured as free chlorine). [R309-200-5(3)(c)(iv)]
Record and report the lowest daily chlorine residual concentration, measured as free chlorine, at the POE sampling location(EP003). [R309-215-10(1)].
Our records show that your water system serves 2,020 people. Please be aware that R309-215-16(3)(b)(iii)(A)(II) requires water systems serving 3,300 people or fewer to monitor the POE
chlorine residuals and take daily grab sample(s). Alternatively, instead of taking daily grab samples, a groundwater system serving 3,300 or fewer people may choose to use an online
analyzer to continuously monitor the POE chlorine residuals entering the distribution system.
Chlorine Residual ‒ Distribution System (DS001)
This water system must maintain a detectable residualthroughout the distribution system. It is recommended to maintain the chlorine residual above 0.1 ppm in the distribution system.
[R309-520-5]
The chlorine residual measured in the distribution system shall not exceed the maximum residual disinfectant level (MRDL) of 4.0 mg/L (measured as free chlorine). [R309-200-5(3)(c)(iv)]
This water system must take a minimum of three (3) chlorine residual samples per weekat varying locations throughout its distribution system (DS001). [R309-105-10(1)(c)]
Distribution system chlorine residuals must be taken in conjunction with total coliform sampling. [R309-215-10(3)]
Disinfection Report Submission
To demonstrate ongoing compliance with secondary disinfection requirements, the water system must complete monthly operational reports for each active chlorinator using a template approved
by the Division. 
The monthly operational reports are submitted quarterly. The reports are due to the Division by the 10th day following the end of each reporting quarter (i.e., January 10th, April 10th,
July 10th and October 10th). The reports can be submitted by hardcopy, fax, or by uploading them to the Division’s chlorine residual reporting form which can be found at MRDL.utah.gov.
Please contact Luke Treutel at [phone] or [e-mail] to schedule training regarding proper reporting.
In addition to monthly disinfection reporting, this water system must submit the monthly average of chlorine residual samples taken in the distribution system. Distribution system chlorine
residual monitoring results are due quarterly by the same compliance dates as the monthly disinfection report and can be submitted via an online form found at mrdl.utah.gov. 
Records must be maintained for a minimum of 5 years. [R309-105-17(1)]
Source Chemical Monitoring
Pursuant to R309-205-7(1)(b)(i), all new sources must complete the initial radionuclide monitoring requirements through quarterly sampling. Additionally, the baseline monitoring frequency
for volatile organics on new sources is one sample per year. The Division understands that the Hole InThe Rock #2 Well (WS008) combines with existing sources at Sampling Station - 01
02 03 08 (SS308). As a result the radionuclide and volatile organic monitoring frequencies have increased at the Sampling Station - 01 02 03 08 (SS308). Quarterly radionuclide samples
should be collected only during periods where the Hole InThe Rock #2 Well (WS008) is actively supplying water to the Sampling Station - 01 02 03 08 (SS308).
The updated monitoring requirements are given below and are available to view anytime on waterlink.utah.gov. Please contact David Kruse at [e-mail] or 385-566-7789 with questions
regarding the source chemical monitoring requirements for this system. Facility with new requirementsAnalyte(s) Required# of samplesSampling FrequencyNext Due DateRule ReferenceSS308
Sampling Station - 01 02 03 08Inorganics & Metals1Every three years01/01/2026-12/31/2028R309-205-5(3)(a)Nitrate1Yearly01/01/2025-12/31/2025R309-205-5(4)(a)Sulfate, Sodium, TDS1Every
three years01/01/2026-12/31/2028R309-205-5(3)(a)Radionuclides1Quarterly07/01/2025-09/30/2025R309-205-7(1)(b)Volatile Organics 1Yearly01/01/2025-12/31/2025R309-205-6(2)PFASCollect (1)
sample every 5-7 monthsduring a12 month period for a total of 2 samples by April 26, 2027.40 CFR 141 (2024)PFAS Information and Resources:The EPA rule for PFAS requires that either
method 533 or 537.1 version 2 are used for testing. Please ensure that the chosen laboratory processes PFAS samples using one of these methods. Additionally, the Division has resources
to assist water systems in completing the PFAS initial monitoring requirements. For more information on the resources the division can provide related to PFAS initial monitoring please
visit ddwpfas.utah.gov. For PFAS related questions, please contact John Steffan at [e-mail] or [phone].