Kinder-Morgan installed monitoring wells around its Yuma Booster Station, which is surrounded by agricultural fields. Two of the monitoring wells are located on the North Gila Thomas estate property. The purpose of the monitoring wells is to provide early detection of potential contaminants associated with the pipeline running through the agricultural fields. MACTEC Engineering and Consulting, Inc. has provided laboratory data since April 2005. However, recent elevated readings of Volatile Fuel Hydrocarbons, Benzene, Toluene, Ethyl benzene, total Xylenes, and Methyl-tert-butyl Ether have caused concern. We have reviewed the groundwater sampling data collected from the two monitoring wells and conducted an assessment to evaluate whether the chemicals are at levels of public health concern.

In September 1999, the U.S. Environmental Protection Agency contacted the Arizona Department of Health Services, Office of Environmental Health, concerning potential contamination of private drinking water wells along Lynx Creek in the Walker, Arizona, mining district. Historical mining activities in the area might have resulted in contamination of groundwater by acid mine runoff as well as metals from extraction processes. EPA and ADHS determined the historical mining activity had caused environmental damage and the potential for adverse human health impacts. ADHS initiated a private well sampling program to determine if the mining activity has had an adverse impact on the quality of water from these wells. Several area residents have expressed concerns about their water quality. The objective of this public health consultation is to evaluate the potential for health effects from exposure to contaminants in private drinking water wells in the Walker, Arizona area.