HIGH DENSITY POLYETHYLENE PIPE FILL HEIGHT TABLE IN ARIZONA Final Report 621 Prepared by: Ahmad Ardani, Jagannath Mallela, Tim Wyatt Applied Research Associates, Inc. 505 W. University Avenue Champaign, IL 61820 November 2006 Submitted to: Arizona Department of Transportation 206 S. 17th Avenue Mail Drop 075R Phoenix, AZ 85007