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Cano & Way Brief Federal Agencies Joe Cano, Materials Engineer, U. S. Department of Interior, Bureau of Indian Affairs, Western States and George Way, Pavement Design Engineer, Arizona Department of Transportation, were invited speakers at the Federal Agency Coordination Meeting regarding the Federal Lands Highway program administered by the FHWA. Cano and Way are regarded as two of the nation's most knowledgeable Asphalt-Rubber experts. Cano, the former Materials Engineer for the City of Phoenix, Arizona, shared his experiences with Asphalt-Rubber for low volume roads, primarily spray applications, with his peers from the other federal agencies involved. Cano told the audience that the Asphalt-Rubber Chip seal which has been used by the BIA since the early 80s was one of the agency's maintenance strategies due to its cost effectiveness for low volume roads. He said the cost effectiveness was based on the 10 to 12 year performance life of the AR Chip seals as opposed to the 5 to 7 year life of the conventional chip seals. Cano noted that AR Chip Seals were far more effective in controlling fatigue cracking. Way related ADOT's successful experience with the gap and open graded Asphalt-Rubber mixes on the state highways and interstate. He pointed out the 10-13 year performance of the AR OGFC on the I-19, the I-17 and the I-40 in northern Arizona which is almost totally paved with AR border to border. States Turn to Asphalt-Rubber for Quieter Pavements From the Interstate 280 in California to the US 60 in Arizona and the I-35 in San Antonio, Texas, state highway agencies are looking at Asphalt-Rubber open graded mixes (Pourous Friction Courses in Texas) as a means of reducing traffic noises on urban freeways. On the west coast, Caltrans is laying a 5.6 mile stretch of Asphalt-Rubber OGFC over old concrete pavement and has hired a consultant to conduct a five year noise study to determine if the pavement will hold the noise reduction over time. According to Dave Tanner, Mayor of Woodside where the I-280 runs adjacent to some of the city's upscale homes, the new AR surface has reduced noise "by about 40%." In Arizona, the resurfacing of the old concrete US 60 with AR OGFC during a major design/build widening project, has generated huge public response. The smooth, quiet freeway has people calling ADOT asking that the freeway in their area also be resurfaced with the material. Radio Talk show hosts and Newspaper Editors have joined the movement, calling for all Urban Freeways to be resurfaced with AR. ADOT has committed to do just that at a cost of approximately $100,000,000 if the special freeway tax is extended by the public. Dr. Hans Zhu of Arizona State University and RPA Deputy Director, Douglas Carlson measured a 9.5 dBs reduction on the US 60 after the AR surface had been applied. ADOT is currently running noise studies on many of it's older AR pavements to determine the reduction capabilities of the material over time. In Texas, TXDOT has embarked on a "smoothness" campaign for the state's roadways. Noticing the quietness of some of the AR projects in service, the agency included a noise study as part of a resurfacing of the I-35 in San Antonio. Sid Cox of Cox Paving was the Asphalt-Rubber contractor on the 11/2 inch Porous Friction Course that was placed over the existing concrete surface. PaveTex Engineering conducted noise measurements prior to and after the new surface was applied. According to Maghsoud Tahmoressi, President of PaveTex, the average reading on the new PFC surface on the I-35 was 10dB quieter than an adjacent section of the old concrete pavement.