As part of the Headworks Odor Control Improvements at Pima County RWRD’s Tres Rios Water Reclamation Facility, contractor SMS Construction needed a fully engineered and factory-tested PLC control panel to bring the new odor control system online. CEI designed and procured the control panel to the agency review set, delivering shop drawings, loop drawings, and an O&M manual submittal, then built, factory acceptance tested, and shipped the panel for installation. The completed panel gave the project a ready-to-install control assembly verified against the design before it reached the field.