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.

The Arizona Department of Environmental Quality and the California Department of Toxic Substance Control worked together to assess background levels of naturally occurring metals in groundwater wells at Topock and Golden Shores, Arizona. The communities expressed concerns regarding the findings, thus the ADEQ requested the Arizona Department of Health Services to evaluate whether these naturally occurring metals in groundwater wells are present at levels that may cause adverse health effects.