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Public water system record

Fort Belknap Agency Water System

Serves Fort Belknap Agency, Blaine County, MT · 2,600 people served

Federal records show 61 health-based violations and 11 monitoring/reporting issues for Fort Belknap Agency Water System in the last ten years. The most serious issue in this window was a Total Trihalomethanes (TTHMs) violation that EPA lists as archived, not resolved.

  • 083090041
  • HARLEM
  • MT
  • 2,600 served

System profile

Source water Surface water
ZIP 59526
EPA system ID 083090041

Verify this system on EPA ECHO →

Health-based violations, last 10 years
61
Resolved
42
Unresolved
0
Archived by EPA
19
Any acute record
No
Monitoring issues, last 10 years
11

Key facts

  • Fort Belknap Agency Water System draws water from 1 surface water intake.
  • Highest measured level in the last 10 years: Total Trihalomethanes (TTHMs), 0.138 mg/L, federal limit 0.08 mg/L (1.7 times the limit), 2021.
  • Most recent enforcement action: boil water order by EPA, December 2025.
  • Record on file since 1976, with 77 health-based violations before October 19, 2016.
  • Lead pipe inventory: 0 lead and 480 unknown out of 480 service lines.

Check whether Fort Belknap Agency Water System serves your address

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Health-based violations

Since October 2016

Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.

Contaminant Rule family Start date Status Acute
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.102 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Oct 1, 2025 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.104 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Jul 1, 2025 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.101 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Apr 1, 2025 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2025 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2025 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.109 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 220 Jan 1, 2025 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.115 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 220 Oct 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.114 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 220 Jul 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.107 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Apr 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.095 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
 220 Jan 1, 2024 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.085 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
 220 Oct 1, 2023 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
 No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.092 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
 220 Jul 1, 2022 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.103 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Apr 1, 2022 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2021 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2021 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.125 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 220 Oct 1, 2021 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.13 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 220 Jul 1, 2021 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.138 mg/L, federal limit 0.08 mg/L (1.7 times the limit)
 220 Apr 1, 2021 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2021 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2021 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2021 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.127 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 220 Jan 1, 2021 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2020 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.119 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 220 Oct 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2020 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.114 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 220 Jul 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2020 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.082 mg/L, federal limit 0.08 mg/L (at or just above the limit)
 220 Apr 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jan 1, 2020 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.088 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
 220 Jan 1, 2020 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Oct 1, 2019 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.1 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Oct 1, 2019 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2019 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2019 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Jul 1, 2019 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.102 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 220 Jul 1, 2019 Resolved No
CARBON, TOTAL
Treatment technique failure
 210 Apr 1, 2019 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.122 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 220 Apr 1, 2019 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.114 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 220 Oct 1, 2018 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.119 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 220 Jul 1, 2018 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.119 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 220 Apr 1, 2018 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.134 mg/L, federal limit 0.08 mg/L (1.7 times the limit)
 220 Jan 1, 2018 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.133 mg/L, federal limit 0.08 mg/L (1.7 times the limit)
 220 Oct 1, 2017 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.13 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 220 Jul 1, 2017 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.124 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 220 Apr 1, 2017 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.117 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 220 Jan 1, 2017 Resolved No
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.113 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 220 Oct 1, 2016 Resolved No

Monitoring and reporting issues

Since October 2016

Missed tests or reports, not contaminants found above a limit.

Issue Start date Status
DICHLOROMETHANE
Monitoring and reporting
 Jan 1, 2025 Resolved
Surface Water Treatment Rule
Monitoring and reporting
 Apr 1, 2020 Resolved
Surface Water Treatment Rule
Monitoring and reporting
 Mar 1, 2020 Resolved
Asbestos
Monitoring and reporting
 Jan 1, 2020 Resolved
Haloacetic Acids (HAA5)
Monitoring and reporting
 Aug 1, 2019 Resolved
Total Trihalomethanes (TTHMs)
Monitoring and reporting
 Aug 1, 2019 Resolved
CARBON, TOTAL
Monitoring and reporting
 Jul 1, 2019 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
CARBON, TOTAL
Monitoring and reporting
 Jul 1, 2019 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
CARBON, TOTAL
Monitoring and reporting
 Jul 1, 2018 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
CARBON, TOTAL
Monitoring and reporting
 Jul 1, 2018 Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
CARBON, TOTAL
Monitoring and reporting
 Jan 1, 2018 Resolved

Full record since 1976

EPA's records for Fort Belknap Agency Water System go back to 1976. Before October 19, 2016 they list 77 health-based violations (53 resolved, 24 archived by EPA without a recorded fix) and 113 monitoring or reporting violations.

Violations that began in Health-based Monitoring and reporting
1970s 0 10
1990s 3 13
2000s 23 79
2010 to October 18, 2016 51 11
October 19, 2016 to 2019 16 7
2020s 44 4

Most recent health-based violation before October 19, 2016: Total Trihalomethanes (TTHMs), began October 2016, Resolved.

Show all 77 health-based violations before October 19, 2016
Contaminant Start date Status
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.113 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 Oct 1, 2016 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.111 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 Jul 1, 2016 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.108 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 Apr 1, 2016 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.127 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 Jan 1, 2016 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.129 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 Oct 1, 2015 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.143 mg/L, federal limit 0.08 mg/L (1.8 times the limit)
 Jul 1, 2015 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.167 mg/L, federal limit 0.08 mg/L (2.1 times the limit)
 Apr 1, 2015 Resolved
CARBON, TOTAL
Treatment technique failure
 Jan 1, 2015 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.157 mg/L, federal limit 0.08 mg/L (2 times the limit)
 Jan 1, 2015 Resolved
CARBON, TOTAL
Treatment technique failure
 Oct 1, 2014 Resolved
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.075 mg/L, federal limit 0.06 mg/L (1.3 times the limit)
 Oct 1, 2014 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.157 mg/L, federal limit 0.08 mg/L (2 times the limit)
 Oct 1, 2014 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.15 mg/L, federal limit 0.08 mg/L (1.9 times the limit)
 Jul 1, 2014 Resolved
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.093 mg/L, federal limit 0.06 mg/L (1.6 times the limit)
 Jul 1, 2014 Resolved
CARBON, TOTAL
Treatment technique failure
 Jul 1, 2014 Resolved
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.074 mg/L, federal limit 0.06 mg/L (1.2 times the limit)
 Apr 1, 2014 Resolved
CARBON, TOTAL
Treatment technique failure
 Apr 1, 2014 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.102 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 Apr 1, 2014 Resolved
CARBON, TOTAL
Treatment technique failure
 Jan 1, 2014 Resolved
Total Coliform
Contaminant limit exceeded
 Nov 1, 2013 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.11 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 Jul 1, 2013 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.098 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
 Apr 1, 2013 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.106 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 Jan 1, 2013 Resolved
CARBON, TOTAL
Treatment technique failure
 Oct 1, 2012 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.122 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 Oct 1, 2012 Resolved
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.062 mg/L, federal limit 0.06 mg/L (at or just above the limit)
 Oct 1, 2012 Archived
CARBON, TOTAL
Treatment technique failure
 Jul 1, 2012 Archived
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.078 mg/L, federal limit 0.06 mg/L (1.3 times the limit)
 Jul 1, 2012 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.123 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 Jul 1, 2012 Resolved
CARBON, TOTAL
Treatment technique failure
 Apr 1, 2012 Archived
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.079 mg/L, federal limit 0.06 mg/L (1.3 times the limit)
 Apr 1, 2012 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.135 mg/L, federal limit 0.08 mg/L (1.7 times the limit)
 Apr 1, 2012 Resolved
CARBON, TOTAL
Treatment technique failure
 Jan 1, 2012 Archived
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.083 mg/L, federal limit 0.06 mg/L (1.4 times the limit)
 Jan 1, 2012 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.128 mg/L, federal limit 0.08 mg/L (1.6 times the limit)
 Jan 1, 2012 Resolved
CARBON, TOTAL
Treatment technique failure
 Oct 1, 2011 Archived
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.079 mg/L, federal limit 0.06 mg/L (1.3 times the limit)
 Oct 1, 2011 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.115 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
 Oct 1, 2011 Resolved
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.071 mg/L, federal limit 0.06 mg/L (1.2 times the limit)
 Jul 1, 2011 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.118 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 Jul 1, 2011 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.116 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 Apr 1, 2011 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.083 mg/L, federal limit 0.08 mg/L (at or just above the limit)
 Jan 1, 2011 Resolved
CARBON, TOTAL
Treatment technique failure
 Oct 1, 2010 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.1233 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 Oct 1, 2010 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Aug 1, 2010 Resolved
CARBON, TOTAL
Treatment technique failure
 Jul 1, 2010 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.117 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
 Jul 1, 2010 Resolved
CARBON, TOTAL
Treatment technique failure
 Apr 1, 2010 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.105 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
 Apr 1, 2010 Resolved
Surface Water Treatment Rule
Treatment technique failure
 Mar 1, 2010 Resolved

27 older violations are not listed here. EPA ECHO has the complete list.

Enforcement actions

EPA took 4 formal enforcement actions against Fort Belknap Agency Water System and issued 1 boil water order between 2007 and 2025, filed as 12 records in EPA's data. The most recent was a boil water order in December 2025.

Date By Action Violations covered
Dec 23, 2025 EPA Boil water order 1 violation
Jan 29, 2021 EPA Compliance order (no penalty) 62 violations (56 health-based): CARBON, TOTAL, Total Trihalomethanes (TTHMs), DICHLOROMETHANE, Haloacetic Acids (HAA5)
Dec 2, 2013 EPA Consent decree or court judgment 112 violations (85 health-based): Haloacetic Acids (HAA5), Total Trihalomethanes (TTHMs), CARBON, TOTAL, Surface Water Treatment Rule, Chlorine
Aug 3, 2009 EPA Consent decree or court judgment 11 violations (11 health-based): Total Trihalomethanes (TTHMs)
Sep 6, 2007 EPA Compliance order (no penalty) 50 violations (19 health-based): Surface Water Treatment Rule, Total Trihalomethanes (TTHMs), Haloacetic Acids (HAA5), Total Coliform, CARBON, TOTAL

What the violations mean

Total Trihalomethanes (TTHMs)

31 incidents

Disinfection byproduct levels exceeded the federal limit

Long-term TTHM exposure may increase bladder cancer risk

CARBON, TOTAL

30 incidents

The system did not complete a treatment step or action that federal rules require for CARBON, TOTAL (a treatment technique violation).

The utility had to notify customers about each of these violations.

Where the water comes from

Fort Belknap Agency Water System draws water from 1 surface water intake.

Annual water quality report

Fort Belknap Agency Water System must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.

Where the state allows it, systems serving fewer than 10,000 people may publish the report in a local newspaper or news site instead of mailing it, and must provide a copy on request.

Find a posted report with EPA's Consumer Confidence Report search

Testing your own water

To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by EPA Region 8.

Certified drinking water labs by state EPA guidance for private wells