The objective of this study was to evaluate the effect of typical chemical winter maintenance practices on Arizona Department of Transportation pavements. A review of previous studies on the effect of deicing/anti‐icing chemicals did not yield definitive recommendations, especially for DIAICs typically used by ADOT. Researchers conducted a laboratory study evaluating the effects of magnesium chloride, potassium chloride, sodium chloride, and distilled water on eight different open‐graded rubber‐modified asphalt concrete mixes using the boiling test. All experimental factors were found to be statistically significant, and the researchers provide recommendations on which DIAICs should be used for different binder and aggregate types.

Land Use and Traffic Congestion is an investigation into the links among land use, travel behavior, and traffic congestion. Researchers focused on four transportation corridors in the Phoenix area: three older neighborhoods with relatively mixed, higher density land use, and one suburban area with lower density but high traffic volumes. The analysis suggested that the higher density corridors exhibited less congestion due to the greater mix of uses, shorter trip lengths, more travel by transit and non-motorized modes, and the presence of a secondary street grid system.

As part of the Long Term Pavement Performance (LTPP) Program, the Arizona Department of Transportation constructed eight Specific Pavement Studies 9 (SPS‐9) test sections on Interstate 10 near Phoenix is an overlay project and is accordingly given independent analysis and documentation in this report separate from Arizona SPS‐9B projects located on US 93, which were new construction and are documented in a separate report. The SPS‐9A project studied the effect of asphalt specification and mix designs on flexible pavements, specifically comparing Superpave binders with commonly used agency binders. Opened to traffic in 1995, the project was monitored at regular intervals until it was rehabilitated in 2005. Surface distress, profile, and deflection data collected throughout the life of the pavement were used to evaluate the performance of various flexible pavement design features, layer configurations, and thickness. This report documents the analyses conducted as well as practical findings and lessons learned that will be of interest to ADOT.

This study investigated whether highways acted as barriers to gene flow for pronghorn in northern Arizona. DNA samples from 132 pronghorn were analyzed using eight polymorphic microsatellite loci. Samples represented animals living on opposite sides of US Route 89 (US 89) and State Route 64 (SR 64). Two different modeling approaches indicated that both US 89 and SR 64, and to a lesser extent US Route 180 (US 180), acted as barriers to gene flow. The genetic structuring caused by highways, especially across US 89, is consistent with behavioral data that demonstrated pronghorn rarely cross this highway. This study found no evidence of inbreeding or reduced genetic variation in any of the populations examined, but those effects may take longer to appear. Based on these results, the researchers recommend future genetic monitoring of these populations or assessment of genetic variation across highways with larger traffic volumes or longer histories to determine whether the barrier effects documented here lead to loss of genetic diversity.

Local residents expressed their concerns regarding the tailings from the Iron King Mine and Humboldt Smelter at Dewey-Humboldt, AZ. The purpose of this health consultation is to evaluate the available water and soil sampling results to determine if the detected metal levels pose adverse health effects when residents come into contact with the water or soil. In 2008, EPA initiated the field investigation portion of the Remedial Investigation and Feasibility Study for the Site. The primary objectives of the RI/FS are to determine the nature and extent of contamination and to gather sufficient information so that EPA can select a long-term remedy that eliminates, reduces, or controls risks to human health. The investigation included the collection of airborne particulates, groundwater, surface water, surface soil, subsurface soil, and sediment data across the entire Site. Data from the RI/FS was not available at the time the health consultation was prepared and thus it was not incorporated into this health consultation.

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.

This report presents an assessment of human health risks from exposure to surface soil metals in the Old Tungsten Mill, Tucson, AZ. City of Tucson officials had planned to build a park, on a parcel of land they owned west of Silverbell Road and north of Speedway Boulevard in Tucson, Pima County, Arizona. They had raised $200,000 in bond money to study what was the Old Tungsten Mill site when they found high levels of contaminants in the soil. The Arizona Department of Health Services, Risk Assessment & Health Consultation Program offered assistance to the city. On October 13th, 2006 City Officials asked ADHS to perform a health consultation to evaluate whether exposure to contaminants in soil pose a public health hazard, either currently or during possible future reuse of the land.

Previous studies at Lake Havasu and Lake Powell, combined with other national data indicate that carbon monoxide poisoning from recreational watercraft can create a significant health hazard. The current study was designed not to repeat the 2003 study. Instead, it was designed to explore the potential health effects of carbon monoxide under the conditions of Humbug Cove. Humbug Cove is known for congregating idling boats, higher frequency of alcohol consumption, and being a location that was secluded and sheltered from breezes or wind.

The Arizona transportation history project was conceived in anticipation of Arizona’s centennial, which will be celebrated in 2012. Following approval of the Arizona Centennial Plan in 2007, the Arizona Department of Transportation recognized that the centennial celebration would present an opportunity to inform Arizonans of the crucial role that transportation has played in the growth and development of the state.

The report consists of a historical narrative and a series of topical essays. The seven-chapter historical narrative is a history of Arizona’s highways that extends from the pre-Columbian era to the present. The 14 topical essays extend the scope of the history beyond the state’s highway system. They include overviews of the development of other transportation modes (railroads, aviation, and urban transit), a brief history of highway pavements, a lighthearted look at the motoring experience during the 1920s and 1930s, and an exploration of how changes in transportation infrastructure affected some Arizona communities. The topical essays also provide additional historical information on bridges, urban freeways, the Interstate system, ADOT and its predecessor agencies, and famous roads such as U.S. Route 66, U.S. Route 89, the Black Canyon Highway, and the Beeline Highway.

The report also includes a timeline of transportation-related developments. This chronology not only provides an accessible overview of Arizona’s transportation history; it also places that history in a larger context by including transportation-related developments from the rest of the nation and around the world. Finally, the report contains a guide to archives in Arizona that hold significant collections of historical photographs related to the state’s transportation history, a bibliography of published historical sources related to the history of highways in Arizona, and a discussion of how the historical narrative and topical essays could be used to produce publications and media that would be made available to the public.