Chip Seals...Meeting the Challenges of Tough Jobs In 2001, Western States Surfacing, Inc. of Modesto, California was the successful bidder on a challenging rehabilitation of Highway 168, the only continuous highway from the Fresno area to Huntington Lake. Over a 40 year span, the highway has seen many changes, the most significant being the four lane section from Prather to Shaver Lake. Since 1965 the road had received two maintenance treatments, the first an overlay project split between 1997 and 1999. Prior to the overlay, about ten miles had received a conventional chipseal in 1987. In summer of 1998, the high elevation (5,000' to 7,500') roadway received a recessed stripe.   While the Caltrans goal was to prolong the service life of the pavement in place, preserving the expensive recessed thermoplastic centerline striping was a requirement of the project specifications. This type of striping was placed because of the winter snow plowing that is common at high elevations. With a stripe below the grade of the roadway it is not stripped away by snowplow blades. Through partnering sessions between the contractor and Caltrans personnel, an innovative paving process was developed that would chip seal on both sides of recessed centerline at approximately 1/2" thickness and provide additional protection for the stripe. This innovation saved California taxpayers a large sum of money on the project.    The Project Resident Engineer, Floyd Davis, praised the workmanship of the Western States Surfacing crews. In a letter dated October 21, 2001, Davis said, "This project had several challenging aspects to it.it was a pleasure working with the contractor to overcome these difficulties and have a very successful project. It is anticipated that the chip seal will add an additional five to six years of life to the existing pavement." Editors note: Given the performance of chip seals in California, it is likely that Mr. Davis is very conservative in his estimation of the service life of this project. Many chip seals in the high country of the state have been performing over 15 years.   The Asphalt-Rubber Chip Seal. This chip seal method typically use a spray application of .55 to .70 gallons psy of hot, reacted Asphalt-Rubber binder* followed by the addition of hot, pre-coated aggregate applied at a rate of 30 to 40 pounds psy. The aggregate is rolled into the hot binder with pneumatic tire rollers. *The Asphalt-Rubber binder is the same used in hotmixes, 80% asphalt reacted with 20+-2% crumb rubber, some agencies may use a diluent such as extender oil and high natural rubber in both the hot mix and spray applications.  Register Now and Save ASPHALT RUBBER 2003 Progress through Flexibility December 2 through 4, 2003 in Brasilia, Brasil An International Conference featuring 50 papers on Asphalt-Rubber by experts from around the world. RPA is co-sponsoring the conference along with the European Tire Recycling Association, Abrapneus, ANIP and A.B.P. Registration fees...Prior to June 1, 2003 $625 USD. June 1 through September 1, 2003, $725 USD Late registration up to conference date, $825 USD. Student fees $325 USD. Register online at ar2003@consulpav.com Credit cards accepted: VISA and MC.