DDW-2025-005804

June 27, 2025
Sent via Email Only
Zachary Renstrom, Manager
Washington County Water Conservancy District
Washington County WCD – Cottam
533 East Waterworks Drive
St. George, Utah 84770
[e-mail]
Subject:Operating Permit, Cottam Well #3 (WS006) and Cottam Well #3 Chlorinator (TP004); Washington County WCD – Cottam, System #27071, File #12871
Dear Zachary Renstrom:The Division of Drinking Water (the Division) received your request for the Operating Permit forforthe Cottam #3 Well and the Cottam Well #3 Chlorinator from Todd
Garder, P.E., Alpha Engineering, on June 11, 2025. The Division issued Plan Approval for drilling this well on January 28, 2022, and Plan Approval for equipping this well and for the
chlorinator on October 28, 2024.
Our understanding of the project was to equip Cottam Well #3 with a 125 horsepower vertical turbine pump that can deliver 1,000 gallons per minute (gpm) of water at 286 feet of head.
The well and pump are housed in a new well house that has all of the required discharge piping and valves. Included as part of the discharge piping is a sand separator with auto flush.
The project also included 1,000 linear feet of 10-inch diameter PVC C900 DR 18 pipe as transmission pipe to connect to the existing transmission pipe and to deliver water to the tanks.
The Cottam Well #3 Chlorinator (TP004) that was included in this project has been completed according to the following:
The Cottam Well #3 Chlorinator (TP004) is a Regal gas chlorinator automatic flow-paced Regal smart valve proportioning system with ECS 400 series scale, and a 216 vacuum regulator 
This chlorinator adds chlorine to the water from Cottam Well #3 (WS006).
This chlorinator provides secondary disinfection in the distribution system. The water system is already chlorinating both of its active water sources (WS002 and WS003). 
The chlorinated water goes directly to the Cottam Storage Tank (ST001) and Cottam 3MG Tank (ST002).
The gas chlorine being used for disinfection meets the ANSI/NSF 60 standard.
The chlorinator is designed to provide a dose of 3.0 mg/l (ppm) based on the design flow of 1,000 gallons per minute (gpm) from Cottam Well #3.
The chlorine dose is adjusted by a manually adjusted rotometer set for the constant flow from Cottam Well #3.
The Point of Entry (POE) sampling location is in the Cottam Well #2B (TP003) chlorinator building and is a Hach continuous chlorine analyzer and takes samples after the system’s two
tanks (ST001 and ST002). This location is already identified as EP002 in the Division’s database.
We have received the following information for Cottam Well #3 (WS006) and Cottam Well #3 Chlorinator (TP004):
Design engineer’s statement of conformance with approval conditions.
Documentation of valid water right (81-4203 (a47770)).
Evidence of O&M manual delivery.
As-built or record drawings.
Documentation that the requirements for coverage under the Washington County source protection ordinance have been met.
Satisfactory bacteriological results as evidence of proper disinfection and flushing.
We have determined that all conditions of operating permit issuance have been met. On this basis, an Operating Permit forCottam Well #3 (WS006) and Cottam Well #3 Chlorinator (TP004)
is hereby issued as constituted by this letter. You may now place Cottam Well #3 (WS006) and Cottam Well #3 Chlorinator (TP004) in service in your water system.
Please maintain a copy of this letter with your permanent records for future reference.
The equipped well pump capacity of Cottam Well #3 is 1,000 gallons per minute (gpm). The safe yield of Cottam Well #3 is rated at 867 gpm, which is calculated based on two-thirds of
the constant-rate aquifer drawdown test results at 1,300 gpm. The safe yield of 867 gpm is the basis for determining the maximum number of connections that Cottam Well #3 can serve.
Monitoring Requirements
Issuance of this operating permit changes the monitoring and reporting requirements for this water system. Please see addendum 1 for an explanation on disinfection requirements.
Pursuant to R309-205-7(1)(b)(i), all new sources are required to complete initial radionuclide monitoring through quarterly sampling. The Division understands that Cottam Well #3 (WS006)
is combined with existing sources at Sampling Station SS051 (SS051). As a result, the radionuclide monitoring frequency has been increased from once every six years to one sample each
quarter.
In addition, Cottam Well #3 does not currently have a “Use” monitoring reduction waiver. Therefore, Sampling Station SS051 (SS051) does not qualify for reduced sampling requirements
for volatile organic compounds (VOCs) and pesticides. The monitoring frequency for both VOCs and pesticides has been increased accordingly.
To apply for a “Use” waiver, which may result in reduced VOC and pesticide monitoring requirements, please contact Noah Zorsky, P.G., at [e-mail] or 385-707-7317.
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 ReferenceSS051
Sampling Station SS051Inorganics & Metals1Every three years01/01/2026-12/31/2028R309-205-5(3)(a)Nitrate1Yearly01/01/2026-12/31/2026R309-205-5(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
Organic Contaminants1Yearly01/01/2026-12/31/2026R309-205-6(2)Pesticides1Every three years01/01/2026-12/31/2028R309-205-6(1)(f)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].
If you have any questions regarding this Operating Permit, please contact J. Paul Wright, P.E., DEQ Southwest District office, at [phone], or Michael Newberry, Permitting and
Engineering Manager, at [phone].
Sincerely,
Russell Seeley, P.E.
Assistant Director
JPW/mrn/mdbEnclosures─ Addendum 1- Elective Monitoring and Reporting Requirementscc: Jeremy Roberts, Southwest Utah Public Health Dept., [e-mail] Gardner, P.E., Alpha

Engineering, [e-mail] Vernon, P.E., Alpha Engineering, [e-mail] Stout, Washington County WCD, [e-mail]. Paul Wright,
P.E., DEQ Southwest District Engineer, [e-mail] Zorsky, P.G., Division of Drinking Water, [e-mail]
David Kruse, Division of Drinking Water, [e-mail]
Jennifer Yee, Division of Drinking Water, [e-mail]
Luke Treutel, Division of Drinking Water, [e-mail] 27071 12871 WS006 OP
Addendum 1
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 EP002 in the Division’s database. This location has been identified as the Cottam Well #2B (TP003) chlorinator building and is a Hach continuous
chlorine analyzer and takes samples after the system’s two tanks (ST001 and ST002). 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 (EP002). [R309-215-10(1)].
Our records show that your water system serves 120 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)]