| Fluoride | 655 ppbaverage of all sampleshighest sample 1,000 ppbdetected in 6 of 6 samples | 4,000 ppb | None published | 2018-2022 |
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| Nitrate | 288 ppbaverage of all sampleshighest sample 400 ppbdetected in 5 of 5 samples | 10,000 ppb | None published | 2018-2022 |
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| Copper | 53 ppbaverage of all sampleshighest sample 53 ppbdetected in 1 of 1 sampleMeasured where water enters the distribution system, not at the tap. EPA's action level applies to tap samples. | 1,300 ppb (EPA action level, 90th percentile) | None published | 2020 |
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| Barium | 33.6 ppbaverage of all sampleshighest sample 120 ppbdetected in 5 of 5 samples | 2,000 ppb | None published | 2018-2022 |
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| Total trihalomethanes (TTHMs) | 18.3 ppbaverage of all sampleshighest sample 54.5 ppbdetected in 240 of 240 samples | 80 ppb | None published | 2018-2022 |
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| Haloacetic acids (HAA9) | 15.3 ppbaverage of all sampleshighest sample 30 ppbdetected in 48 of 48 samples | No federal limit | None published | 2019-2020 |
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| Haloacetic acids (HAA5) | 14.5 ppbaverage of all sampleshighest sample 38.3 ppbdetected in 241 of 241 samples | 60 ppb | None published | 2018-2022 |
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| Dichloroacetic acid | 8.26 ppbaverage of all sampleshighest sample 20.9 ppbdetected in 144 of 145 samples | Counts toward the 60 ppb limit for haloacetic acids (HAA5) | None published | 2020-2022 |
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| PFPeA | 6.54 pptaverage of all sampleshighest sample 8.4 pptdetected in 8 of 8 samples | No federal limit | None published | 2023-2025 |
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| PFBS | 4.41 pptaverage of all sampleshighest sample 6.4 pptdetected in 8 of 8 samples | No federal limit | 2,000 ppt | 2023-2025 |
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| PFHxA | 4.4 pptaverage of all sampleshighest sample 6 pptdetected in 7 of 8 samples | No federal limit | None published | 2023-2025 |
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| PFOSEPA's 2024 rule sets a limit of 4.0 ppt; water systems must meet it by April 2029. In May 2026 EPA proposed allowing extensions to April 2031. EPA's goal (MCLG) is zero. | 3.39 pptaverage of all sampleshighest sample 6.9 pptdetected in 5 of 8 samples | 4 ppt | None published | 2023-2025 |
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| PFBA | 3.04 pptaverage of all sampleshighest sample 6.4 pptdetected in 4 of 8 samples | No federal limit | None published | 2023-2025 |
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| Trichloroacetic acid | 2.57 ppbaverage of all sampleshighest sample 12.5 ppbdetected in 125 of 146 samples | Counts toward the 60 ppb limit for haloacetic acids (HAA5) | None published | 2020-2022 |
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| Dibromoacetic acid | 2.04 ppbaverage of all sampleshighest sample 3.33 ppbdetected in 143 of 144 samples | Counts toward the 60 ppb limit for haloacetic acids (HAA5) | None published | 2020-2022 |
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| PFHxSEPA set a limit in 2024 and proposed withdrawing it in May 2026. | 1.48 pptaverage of all sampleshighest sample 4.1 pptdetected in 3 of 8 samples | 10 ppt | None published | 2023-2025 |
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| Monobromoacetic acid | 1.29 ppbaverage of all sampleshighest sample 6.42 ppbdetected in 103 of 146 samples | Counts toward the 60 ppb limit for haloacetic acids (HAA5) | None published | 2020-2022 |
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| PFOAEPA's 2024 rule sets a limit of 4.0 ppt; water systems must meet it by April 2029. In May 2026 EPA proposed allowing extensions to April 2031. EPA's goal (MCLG) is zero. | 1.13 pptaverage of all sampleshighest sample 4.6 pptdetected in 2 of 8 samples | 4 ppt | None published | 2023-2025 |
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| Monochloroacetic acid | 1.09 ppbaverage of all sampleshighest sample 5.96 ppbdetected in 76 of 146 samples | Counts toward the 60 ppb limit for haloacetic acids (HAA5) | None published | 2020-2022 |
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| Manganese | 0.5 ppbaverage of all sampleshighest sample 1.1 ppbdetected in 5 of 8 samples | No federal limit | None published | 2019-2020 |
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| PFHpA | 0.49 pptaverage of all sampleshighest sample 3.9 pptdetected in 1 of 8 samples | No federal limit | None published | 2023-2025 |
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| Aluminum* | 15 ppbaverage of all sampleshighest sample 55 ppbdetected in 8 of 11 samples | No federal limit | None published | 2018-2022 |
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| Nitrite* | 7.81 ppbaverage of all sampleshighest sample 150 ppbdetected in 3 of 36 samples | 1,000 ppb | None published | 2018-2022 |
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| Selenium* | 1.1 ppbaverage of all sampleshighest sample 11 ppbdetected in 1 of 10 samples | 50 ppb | None published | 2018-2022 |
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| Radium-226 + Radium-228* | 0.61 pCi/Lsum of the radium-226 and radium-228 averages | 5 pCi/L | None published | 2018-2022 |
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| Radium-226* | 0.53 pCi/Laverage of all sampleshighest sample 1.2 pCi/Ldetected in 9 of 12 samples | Counts toward the combined 5 pCi/L limit for radium-226 and radium-228 | None published | 2018-2022 |
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| Uranium* | 0.47 ppbaverage of all sampleshighest sample 1.49 ppbdetected in 8 of 12 samples | 30 ppb | None published | 2018-2022 |
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