Upper Occoquan Sewage Authority

The Upper Occoquan Service Authority (UOSA) Primary Clarifiers, Odor Control and Hydraulic Improvements (Contract 4) Project, located in Centreville, Virginia, included the delivery of six round overhead truss supported Hallsten aluminum covers as part of this treatment plant’s primary clarifier upgrades. The reduced foul air headspace beneath these large flat Hallsten aluminum cover systems require less energy to scrub the foul air versus a dome cover, resulting in long term cost savings for the Owner. The flat aluminum cover design also allows plant personnel to access the equipment at the center of the clarifier from above without needing the confined air space equipment or entry procedures often associated with dome covers.