The Rodeo-Chediski Fire Complex began as a small blaze in a remote region of east-central Arizona and within days erupted into the largest wildfire in Arizona history. Fortunately, no lives were lost. However, from June 18, 2002 to the time of its containment on July 7, 2002, the Rodeo-Chediski fire destroyed over 490 structures and 467,000 acres of ponderosa pine and pinyon-juniper woodland—an estimated 500 million to 1.3 billion board feet of timber. Jurisdictions involved included the Fort Apache Indian Reservation, the Apache-Sitgreaves National Forest, the Tonto National Forest, and private lands adjacent to Highway 260, from the Town of Forest Lakes east to the City of Show Low. Virtually all of the acres burned were in Navajo County, with some damage in the contiguous counties of Coconino, Apache, and Gila Counties. This health assessment describes the fire events and summarizes the resulting public health impacts from the fire.

The Arizona Department of Health Services received a request for a Health Consultation from the City of Litchfield Park, dated March 5, 2007. The nature of the request was for ADHS to determine if there was a risk to public health from eating fish taken from Tierra Verde Lake. The City sponsors an annual fishing derby and believed that some citizens were eating the fish they caught. The City tested their lake water and for the very first time, measurable amounts of perchlorates were detected. The probable source for the perchlorates was thought to be from a groundwater, contaminant plume originating from the Phoenix Goodyear Airport Superfund Site.