The Arizona Department of Environmental Quality asked the Arizona Department of Health Services to evaluate the health threat to residents from exposures to ash fallout from a fire at an asphalt plant located on the Salt River Indian Reservation in Mesa, Arizona. The facility has recently been bought by Vulcan, Inc. The site is located just north of the Salt River between Dobson and Alma School Roads. April 13, 1999.

The Stoneridge subdivision is a growing rural community with approximately 5,000 residents. The Prescott Valley Water Company (Prescott Valley, AZ) provides drinking water for residents in this area. A resident in the community indicated that there is a “paint thinner” type odor coming from the tap water. The Prescott Valley Water Company sampled the water due to request of the resident. On July 27, 2004, the resident called the Arizona Department of Health Services to express his/her concern regarding the analytical results of benzene in tap water samples collected from faucets inside the house. As a result, the Arizona Department of Health Services completed a health consultation to evaluate if benzene and other volatile organic compounds in the water supplied by the Prescott Valley Water Company pose any adverse health effects.