Each year vehicular accidents cause gasoline and diesel spills on Arizona roadways. ADOT currently uses Micro-Blaze®, a commercially available microbial solution, as a supplement to natural degradation of vehicular petroleum spills in soils. With an emphasis on minimizing or eliminating environmental and public health hazard, ADOT is interested in determining cost-effective methods to address spills involving petroleum products from roadway vehicular accidents. This study investigated whether Micro-Blaze, Hydro Clean®, Miracle-Gro®, or water accelerated the degradation process significantly over natural processes and that it will help to determine their effectiveness in accelerating the remediation of petroleum products (diesel No. 2 and unleaded gasoline) on predominant Arizona soil types from roadway vehicular accidents.

The Agency for Toxic Substances and Disease Registry has asked the Arizona Department of Health Services, Office of Environmental Health, to conduct a health assessment for the off-site residential area located adjacent to the Tucson Industrial Center, also known as the 3 Hangars site, within the larger Tucson International Airport Area Superfund site, in Tucson, Arizona. Previous investigations found that elevated levels of polychlorinated biphenyls (PCBs) in the drainage areas at the TIC site had migrated off-site into residential areas presenting a health threat to residents. The purpose of this Public Health Assessment is to evaluate if a public health hazard still exists since the remediation activities have been conducted at the off-site El Vado residential area. ADHS concludes that no current public health hazard exists as a result of ingestion, dermal, or inhalation exposures by residents, children, or transients to the post remediated soil in the residential areas on El Vado Road. Replacement of the top soil with certified clean soil has removed all contact with the soil containing PCBs eliminating any future public health hazard.