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Mark Walker

University of Nevada Cooperative Extension, Interim Director

Contact Information


  • English and Journalism, S.U.N.Y Binghamton
  • University of Arizona
  • Cornell University, 1998

Research Interests

My research supports exposure assessment as a part of risk assessment associated with human health protection. I have conducted studies of exposure and potential for exposure to:

  • Arsenic in private water supplies
  • E. coli, as an indicator of fecal contamination in water
  • Leptospira, as a result of changes in land use in Hawaii
  • Cryptosporidium

My extension work provides technical support and information through:

  • Water supply operators throughout Nevada, using an innovative partnership and distance learning technologies
  • Web sites that help interpret water quality and have served as models for at least two national efforts,
  • Peer-reviewed fact sheets and special publications and newsletters
  • Small grants programs for Extension Educators.

Class Materials

Selected Publications

  • Walker, M. J., Pritsos, C., Seiler, R. 2012, Review of the Churchill County, NV ALL cluster, 1997-2004, Chemico-Biological Interactions, Vol 196, Issue 3, pg 52-58
  • Dunkell, D., Bruland, G., Evensen, C., Walker, M. J. 2011, Effects of Feral Pig (Sus scrofa) Exclusion on Enterococci in Runoff from the Forested Headwaters of a Hawaiian Watershed, Water Air and Soil Pollution, 221(1-4), 313-326
  • Ragosta, G., Evensen, C., Atwill, E., Walker, M. J., Ticktin, T., Asquith, A., Tate, K. 2011, Risk factors for elevated Enterococcus concentrations in a rural tropical island watershed, Journal of Environmental Management, 92(8), 1910-1915
  • Ragosta, G., Evensen, C., Atwill, E. R., Walker, M. J. 2010, Causal Connections between Water Quality and Land Use in a Rural Tropical Island Watershed., J. Ecohealth. 7:105-113
  • Newman, J., Walker, M. J. 2010, Short-term releases of arsenic, lead and uranium following oxidation by shock chlorination., Journal of Water and Health/International Water Association.
  • Walker, M. J., Fosbury, D. 2009, Exposure to Arsenic, As(III) and Tungsten through private domestic water supplies., Journal of Water and Health, 7(2), 293-301.
  • Fosbury, D., Walker, M. J., Stillings, L. 2008, Chemical Analyses of Ground Water in the Carson Desert near Stillwater, Churchill County, Nevada, 2005, Washington, D.C./U.S. Geological Survey: Open File Report/U.S. Geological Survey, (pp. 17 pages).
    Professional Papers
  • Walker, M. J. 2008, ). Method Development and Preliminary Applications for Leptospira Spirochetes in Water Samples: EPA/600/R 08/17., Cincinnati, OH: U.S. Environmental Protection Agency's National Homeland Security Research Center, Cincinnati, OH.
    Curriculum Development
  • Walker, M. J. 2009, Water Treatment Plant Operators' Instructional Video: Review, Examples and Practice Problems, University of Nevada Cooperative Extension. (ed., pp. 50).


  • Parker, J., Walker, M. J. (2009). 2009, Water Treatment Plant Operators' Instructional Video., University of Nevada Cooperative Extension.

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