Clarifier mechanisms from Walker Process Equipment, A Division of McNish Corp., are available from the most basic type of bridge or pier supported to those with the most complex and demanding requirements. Specialized modifications include seismic design, special materials of construction, deflection-limited design and custom features to suit existing infrastructure. Nearly every component is modifiable, including the bridge and superstructure, influent arrangement, sludge removal method of plowing with spiral or conventional flights, rapid (hydraulic) sludge removal systems and many types of skimming options. Drives are made with corrosion-resistant cast-iron housings and precision gearing and bearings that have a proven life span of over 50 years. 630/892-7921; www.walker-process.com.