The chemical quality of self-supplied domestic well water in the United States
Abstract
Abstract Existing water quality data collected from domestic wells were summarized to develop the first national‐scale retrospective of self‐supplied drinking water sources. The contaminants evaluated represent a range of inorganic and organic compounds, and although the data set was not originally designed to be a statistical representation of national occurrence, it encompasses large parts of the United States including at least some wells sampled in every state and Puerto Rico. Inorganic contaminants were detected in many of the wells, and concentrations exceeded the U.S. EPA maximum contaminant levels (MCLs; federal drinking water standards used to regulate public drinking water quality) more often than organic contaminants. Of the inorganic constituents evaluated, arsenic concentrations exceeded the MCL (10 μg/L) in ∼11% of the 7580 wells evaluated, nitrate exceeded the MCL (10 mg/L) in ∼8% of the 3465 wells evaluated, uranium‐238 exceeded the MCL (30 μg/L) in ∼4% of the wells, and radon‐222 exceeded 300 and 4000 pCi/L (potential drinking water standards currently under review by the U.S. EPA) in ∼75% and 9% of the wells, respectively. The MCLs for total mercury and fluoride were each exceeded in <1% of the wells evaluated. The MCL was exceeded in <1% of all wells for all anthropogenically derived organic contaminants evaluated and was not exceeded for many contaminants. In addition, 10 contaminants evaluated do not currently have an MCL. Atrazine, however, was detected in 24% of the wells evaluated and was the most frequently detected organic contaminant of the 28 organic contaminants evaluated in this study. Simazine and metolachlor each were detected in ∼9% of all wells and tied for second in frequency of detection for organic contaminants. The third and fourth most frequently detected organic contaminants were methyl tert ‐butyl ether (MTBE) (6%) and chloroform (5%), respectively. Because the water quality of domestic wells is not federally regulated or nationally monitored, this study provides a unique, previously nonexistent, perspective on the quality of the self‐supplied drinking water resources used by ∼45 million Americans in the United States.
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Among 3465 domestic wells tested throughout the US, 90% had >0.01 mg/L nitrate, 8% had >10 mg/L nitrate, and the mean concentration was 3.6 mg/L.
“Among 3465 domestic wells tested throughout the US (Focazio et al., 2006), 90% had N0.01 mg/L NO 3 -(compared with 80% in our study), 8% had N 10 mg/L NO 3 -(compared with 5% in our study), and the mean concentration was 3.6 mg/L (compared with 2.9 mg/L in our study).”
From Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer (2016) · cites this paper as Focazio et al., 2006
A compilation of domestic well testing throughout the US showed exceedances of drinking water standards in 8.4% of wells for nitrate and 11% of wells for arsenic.
“a compilation of domestic well testing throughout the US showed exceedances of drinking water standards in 8.4% of wells for nitrate and 11% of wells for arsenic (Focazio et al., 2006)”
From Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer (2016) · cites this paper as Focazio et al., 2006
The distribution of nitrate in this study was similar to that of Focazio et al.'s broader nationwide study, although their sampling was not part of a nationally representative sampling design.
“This comparison suggests that the distribution of [NO 3 -] in our study was similar to that of Focazio et al.'s broader nationwide study, although their sampling was not part of a nationally representative sampling design.”
From Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer (2016) · cites this paper as Focazio et al., 2006
Cites
Less than obvious - statistical treatment of data below the detection limit
Helsel, D. R. (1990) · Environmental Science & Technology · doi:10.1021/es00082a001 · Cited by 681 · see citing works
Estimated Use of Water in the United States in 2000
Hutson, S. S., Barber, N. L., Kenny, J. F., Linsey, K. S., Snavely, D. S., & Maupin, M. A. (2004) · U.S. Geological Survey circular/U.S. Geological Survey Circular · doi:10.3133/cir1268 · Cited by 481 · see citing works
Gilliom, R. J., Alley, W. M., & Gurtz, M. E. (1995) · U.S. Geological Survey circular/U.S. Geological Survey Circular · doi:10.3133/cir1112 · Cited by 362 · see citing works
The Occurrence of Radioactivity in Public Water Supplies in the United States
Hess, C. T., Michel, J., Horton, T. R., et al. (1985) · Health Physics · doi:10.1097/00004032-198505000-00002 · Cited by 239 · see citing works
Focazio, M. J., Welch, A. H., Watkins, S. A., et al. (2000) · doi:10.3133/wri994279 · Cited by 165 · see citing works
Self-citationArsenic in ground water used for drinking water in the United States
Ryker, S. J. (2005) · Kluwer Academic Publishers eBooks · doi:10.1007/0-306-47956-7_6 · Cited by 32 · see citing works
SHAPIRO, S., Busenberg, E., Focazio, M. J., et al. (2004) · The Science of The Total Environment · doi:10.1016/j.scitotenv.2003.09.007 · Cited by 28 · see citing works
Self-citationMoran, M. J., Lapham, W. W., Rowe, B. L., et al. (2002) · doi:10.3133/wri024085 · Cited by 25 · see citing works
Arsenic concentrations in private bedrock wells in southeastern New Hampshire
Montgomery, D. L., Ayotte, J. D., Carroll, P. R., et al. (2003) · Fact sheet · doi:10.3133/fs05103 · Cited by 21 · see citing works
Radium and radon in ground water in the Chickies Quartzite, southeastern Pennsylvania
Senior, L. A., & Vogel, K. L. (1995) · doi:10.3133/wri924088 · Cited by 19 · see citing works
Zimmerman, T. M., Zimmerman, M. L., & Lindsey, B. D. (2001) · doi:10.3133/wri014206 · Cited by 14 · see citing works
Lapham, W. W., & Tadayon, S. (1996) · Antarctica A Keystone in a Changing World · doi:10.3133/ofr96199 · Cited by 14 · see citing works
Naturally occurring radionuclides in the ground water of southeastern Pennsylvania
Sloto, R. A. (2000) · Fact sheet · doi:10.3133/fs01200 · Cited by 11 · see citing works
Job, C. A. (2002) · Groundwater Monitoring & Remediation · doi:10.1111/j.1745-6592.2002.tb00310.x · Cited by 4 · see citing works
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Schaider, L. A., Ackerman, J. M., & Rudel, R. A. (2016) · Science of The Total Environment · doi:10.1016/j.scitotenv.2015.12.081 · Cited by 182 · see citing works
Bradley, P. M., LeBlanc, D. R., Romanok, K. M., Smalling, K. L., Focazio, M. J., Cardon, M. C., Clark, J. M., Conley, J. M., Evans, N., Givens, C. E., et al. (2021) · Environment International · doi:10.1016/j.envint.2021.106487 · Cited by 43 · see citing works
Self-citation
- Authors
- Focazio, M. J., Tipton, D., Dunkle Shapiro, S., & Geiger, L. H.
- ORCID
- Focazio, Michael J.
- Venue
- Groundwater Monitoring & Remediation
- Publisher
- Wiley
- Published
- 2006-06
- Volume
- 26
- Issue
- 3
- Pages
- 92-104
- ISSN
- 1069-3629 (ISSN-L)
- 1745-6592
- OpenAlex
- W2125362072
- Cited by
- 99
- References
- 14
- Citations by year
- 2026: 3 · 2025: 6 · 2024: 6 · 2023: 9 · 2022: 12 · 2021: 6 · 2020: 5 · 2019: 6 · 2018: 5 · 2017: 5 · 2016: 5 · 2015: 3 · 2014: 4 · 2013: 3 · 2012: 3
- FWCI
- 4.18
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Groundwater Monitoring & Remediation (publishedVersion)
- Topics
- Physical Sciences › Environmental Science › Water Science and Technology › Water Quality and Resources Studies
- Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Water Treatment and Disinfection
- Physical Sciences › Environmental Science › Water Science and Technology › Water Quality and Pollution Assessment
- Keywords
- domestic well water, groundwater quality, inorganic contaminants, organic pollutants, arsenic, nitrate, uranium-238, radon-222, mercury, fluoride, atrazine, simazine, metolachlor, methyl tert-butyl ether, chloroform, maximum contaminant levels
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