The 30-yard Open-Top Roll-off Dewatering Unit from AQUA-Zyme Disposal Systems can be filled with 22,000 to 25,000 gallons of biosolids at 1 to 2 percent solids in about two hours. After draining 24 hours, the unit can be picked up using a standard-capacity roll-off truck and transported for solids disposal. Sludge volume can be reduced by 80 percent with reductions to 98 percent in BOD, COD, FOG and TSS. It has few moving parts, and the size of the filter media can be selected according to the particulars of the job. Standard equipment includes a roll-over tarp system; side, floor and center screens; 1/4-inch floor plate; seven-gauge side plates; four door binder ratchets; eight drain ports; two inlet ports; and a long-handle scraper. The average life span is 12 to 14 years. Units are also available in a 15-yard size. 979/245-5656; www.aqua-zyme.com.