The Santa Cruz County Health Department and the sheriff's office, along with the U.S. Border Patrol have expressed concerns regarding incidental contact with the water in Nogales Wash, Arizona. The public has expressed significant concern about direct public exposure to waters flowing in the wash. The Arizona Department of Health Services completed this health consultation to evaluate the levels of organic and inorganic chemicals at the request of the Santa Cruz County Health Department.

The Miller Road Treatment Facility was built by the North Indian Bend Wash Participating Companies to treat groundwater in order to reduce the levels of volatile organic compounds that have contaminated the aquifers. The facility was brought on-line in March 1997, and ownership was transferred to AAWC in December 1997. The facility processes the groundwater to remove the VOCs. Between January 15–17, 2008 trichloroethylene (TCE) was detected in the Paradise Valley Water System. Arizona American Water Company, who own and operate the Paradise Valley system, contacted the Arizona Department of Health Services and requested assistance in determining possible health risks from exposures related to this incidence. In response, the Arizona Department of Health Services reviewed existing data and performed a health consultation to evaluate the possibility of adverse health effects associated with this event.