Environmental Geochemistry and Health

, Volume 26, Issue 1, pp 69–79 | Cite as

Health Risks Associated with Contamination of Groundwater by Abandoned Mines Near Twisp in Okanogan County, Washington, USA



Abandoned mines are known to contaminate private drinking water wells with toxic metals and arsenic (As). Little attention is given, however, to sites in rural areas with low population densities where natural, geogenic sources of contaminants might also occur. This study measured arsenic and trace element exposure among residents consuming water from wells adjacent to abandoned mines near Twisp, in Okanogan County, Washington, USA, estimated the risk of adverse health effects, and considered the degree of uncertainty associated with the assessed risk. Water samples were collected between October 1999 and June 2001. Average As concentrations ranged from <1 to 298 µg L−1, lead (Pb) ranged from 0 to 94 µg L−1, cadmium (Cd) 0–5 µg L−1, and selenium (Se) 0–390 µg L−1. Concentrations varied seasonally with maximum concentrations occurring in conjunction with snow-melt. The calculated risk of mortality from cancer following exposure to As at average concentrations as low as 8 µg L−1 was greater than one in 10,000. Additional noncarcinogenic risks are associated with exposure to As, Cd, Pb and Se. A potentially affected population, estimated to be between 1000 and 1287 residents, live within a 6.5-km (4-mile) radius of the study site. This study emphasises the need to test drinking water wells in the vicinity of abandoned mines during times of maximum snow-melt to determine the extent of risk to human health. Residents drinking water from wells tested in this study who want to reduce the estimated carcinogenic risk and the noncarcinogenic hazard quotient should consider treating their water or find alternative sources.

abandoned mines arsenic carcinogenic risk drinking water contamination exposure health effects noncarcinogenic risk trace metals uncertainty 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Andonaegui C. 2000 Salmon and Steelhead Habitat Limiting Factors Water Resource Inventory Area 48. Methow Watershed. Washington State Conservation Commission, Olympia, WA.Google Scholar
  2. ATSDR. 1989 Agency for Toxic Substances and Disease Registry. Decision guide for identifying substance-specific data needs related to toxicological profiles; notice. Fed Register 54(174), 37618–37634.Google Scholar
  3. Barksdale JD. 1975 Geology of the Methow Valley, Okanogan County, Washington. Olympia, Washington: State ofWashington Department of Natural Resources.Google Scholar
  4. Barnes DG, Dourson M. 1988 Reference dose (RfD): description and use in health risk assessments. Regul Toxicol Pharm 8, 471–486.Google Scholar
  5. Berner RA. 1981 A new geochemical classification of sedimentary environments. J Sediment Petrol 51, 359–365.Google Scholar
  6. Bunning BB. 1990 Geologic Map of the East Half of the Twisp 1:100,000 Quadrangle, Washington. Olympia, WA: Department of Natural Resources.Google Scholar
  7. Burnet FW. 1976 Felsic Volcanic Rocks and Mineral Deposits in the Buck Mountain Formation Andesites, Okanogan County, Washington, MSc Thesis, Geology. Seattle: University of Washington.Google Scholar
  8. Calow P. 1998 Handbook of Environmental Risk Assessment and Management. Oxford: Blackwell Science.Google Scholar
  9. Cebrian ME, Albores A, Aguilar M. 1983 Chronic As poisoning in the north of Mexico. Hum Toxicol 2, 121–133.Google Scholar
  10. Chiou HY, Chiou ST, Hsu H, Chou YL, Tseng CH, Wei ML, Chen CJ. 2001 Incidence of transitional cell carcinoma and arsenic in drinking water: a follow-up study of 8102 residents in an arseniasis-endemic area in northeastern Taiwan. Am J Epidemiol 153(5), 411–418.Google Scholar
  11. Crepin J, Johnson RL. 1993 Soil sampling for environmental assessment. In Carter MR, ed. Soil Sampling and Methods of Analysis. Boca Raton: Lewis Publishers.Google Scholar
  12. DHHS US. 2000 Toxicological Profile for Arsenic (Update). Atlanta, Georgia: Agency for Toxic Substances and Disease Registry (ATSDR).Google Scholar
  13. EPA (US Environmental Protection Agency). 1980 Water quality criteria documents; availability. Fed Register (28 November) 45(231), 79318–79379.Google Scholar
  14. EPA (US Environmental Protection Agency). 2000a Alder Mine Site Phase 1 and Phase 2 Preliminary Assessment/Site Inspection Report. TDD:99-04-0004. US Environmental Protection Agency (Region 10), Superfund Technical Assessment and Response Team. Seattle, WA.Google Scholar
  15. EPA (US Environmental Protection Agency). 2000b Setting Standards for Safe Drinking Water. www.epa.gov/safewater/ standards/setting.htmlGoogle Scholar
  16. EPA (US Environmental Protection Agency). 2000c 40CFR Part 141 and 142. National Primary Drinking Water Regulations. Arsenic and Clarification to Compliance and New Source Contaminants Monitoring. Notice of proposed rulemaking. Fed Register (22 June) 65(121), 38887–38983.Google Scholar
  17. EPA (US Environmental Protection Agency). 2001a National Functional Guidelines. www.epa.gov/region9/qa/supfundclp/ doc.htmlGoogle Scholar
  18. EPA (US Environmental Protection Agency). 2001b National primary drinking water regulations; arsenic and clarifications to compliance and new source contaminants monitoring. Fed Register 66(4), 6976–7066.Google Scholar
  19. Felter SP, Dourson ML, Patterson J. 1998 Assessing risks to human health from chemicals in the environment. In Calow P, ed. Handbook of Environmental Risk Assessment and Management. Malden, MA: Blackwell Science.Google Scholar
  20. Ferreccio C, Gonzalez C, Milosavljevic V, Marshall G, Sancha AM, Smith AH. 2000 Lung cancer and arsenic concentrations in drinking water in Chile. Epidemiology 11(6), 673–679.Google Scholar
  21. Garrigues RS, Carey B. 1999 Ground-Water Data Compilation for the Okanogan County Watershed. Report No. 99-342, Olympia, Washington: Washington State Department of Ecology.Google Scholar
  22. Gray DT, Suman VJ, Daniel Su WP, Clay RP, Harmsen WS, Roenigk RK. 1997 Trends in the population-based incidence of squamous cell carcinoma of the skin first diagnosed between 1984 and 1992. Arch Dermatol 133, 735–740.Google Scholar
  23. Hindmarsh JT, McLetchie OR, Heffernan LPM. 1977 Electromyographic abnormalities in chronic environmental arsenicalism. J Anal Toxicol 1, 270–276.Google Scholar
  24. IRIS. 2001 Arsenic. Integrated Risk Information System, US Environmental Protection Agency. Last Update 9 October 2001. http://www.epa.gov/iris/subst/index.htmlGoogle Scholar
  25. Langmuir D. 1997 Aqueous Environmental Geochemistry. New Jersey: Prentice Hall, 600 p.Google Scholar
  26. NAS (National Academy of Sciences). 2001 Arsenic in Drinking Water 2001 Update. Subcommitte on Toxicology, Board on Environmental Studies and Toxicology, Division on Earth and Life Sciences, National Academy of Sciences-National Research Council. Washington, DC: National Academy Press.Google Scholar
  27. NRC (National Research Council). 2001 Arsenic in Drinking Water. Washington, DC: National Academy Press.Google Scholar
  28. Oehme FW. 1978 Toxicity of Heavy Metals in the Environment. New York: Marcel Dekker, Inc.Google Scholar
  29. Opresko DM. 1992 Toxicity Summary for Inorganic Arsenic. Chemical Hazard Evaluation and Commnication Group, Biomedical and Environmental Information Analysis Section, Health and Safety Research Division, Oak Ridge, Tennessee: Oak Ridge National Laboratory.Google Scholar
  30. Oscarson DW, Huang PM, Defosse C, Herbillon A. 1981 Oxidative power of Mn(IV) and Fe(III) oxides with respect to As(III) in terrestrial and aquatic environments. Nature 191, 50–51.Google Scholar
  31. Petts J. 1998 Risk assessment and management for waste treatment and disposal. In Calow P, ed. Handbook of Environmental Risk Assessment and Management. Malden, MA: Blackwell Science.Google Scholar
  32. Plumlee GS, Smith KS, Montour MR, Ficklin WH, Mosier EL. 1999 The environmental geochemistry of mineral deposits. In Plumlee GS, Logsdon MJ, Filipek LH, eds. Reviews in Economic Geology. Vol 6. pp. 373–432.Google Scholar
  33. Roeder R. 2000 Twisp Wells Project. LIMS Project ID: 3410-00. Yakima, WA: Washington State Department of Ecology.Google Scholar
  34. San Juan C. 1994 Natural Background Soil Metals Concentrations in Washington. Washington State Department of Ecology. Toxics Cleanup Program. Publication #94-115.Google Scholar
  35. SKCPH. 2000 Preliminary Findings from Soil Sampling of Maury/Vashon Island and the Southern Mainland Coastline of King County. Seattle, WA: Seattle & King County Public Health (SKCPH).Google Scholar
  36. Southwick JW, Western AE, Beck MM. 1981 Community Health Associated with Arsenic in Drinking Water in Millard County, Utah. Cincinnati, OH: US Environmental Protection Agency, Health Effects Research Laboratory, EPA-600/1-81-064. NTIS No. PB82-108374.Google Scholar
  37. Spencer MJ. 1986 Site Inspection Report Alder Mill Twisp, Washington. Washington State Olympia, Washington: Department of Ecology, Hazardous Waste Cleanup Program.Google Scholar
  38. Stewart BM. 1995 Investigation of Acid Production, Leaching and Transport of Dissolved Metals at an Abandoned Sulfide Tailings Impoundment: Monitoring and Physical Properties. Report of Investigations 9577. United States Department of Interior, United States Bureau of Mines.Google Scholar
  39. Stumm W, Morgan JJ. 1996 Aquatic Chemistry, 3rd edn, NY: John Wiley & Sons, 1022 p.Google Scholar
  40. Tamaki S, Frankenberger Jr WT. 1992 Environmental biochemistry of arsenic. Rev Environ Contam Toxicol 124, 79–109.Google Scholar
  41. Tseng WP. 1977 Effects and dose-response relationships of skin cancer and Blackfoot disease with arsenic. Environ Health Persp 19, 109–119.Google Scholar
  42. Tseng WP, Chu HM, How SW. 1968 Prevelance of skin cancer in an endemic aea of chronic arsenicism in Taiwan. J Nat Cancer Inst 40, 453–463.Google Scholar
  43. USFS (United States Forest Service). 1999 ArcInfo Export Files, in Stateplane. Okanogan, WA: GIS Section, Okanogan National Forest.Google Scholar
  44. Vink BW. 1996 Stability relations of antimony and arsenic compounds in the light of revised and extended Eh-pH diagrams. Chem Geol 130, 21–30.Google Scholar
  45. WAC 173-200-010. 1992 Water Quality Standards for Groundwaters of the State of Washington.Google Scholar
  46. Wait Jr RB. 1972 Geomorphology and Glacial Geology of the Methow Drainage Basin, Eastern North Cascade Range, Washington. PhD Dissertation, Seattle: University of Washington.Google Scholar
  47. Walters KL. 1974 Water in the Okanogan River Basn, Washington: Washington State Department of Ecology Water Supply Bulletin 34, 136 p.Google Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  1. 1.College of Forestry, University of WashingtonSeattleUSA

Personalised recommendations