Performed pre-design site investigation to confirm/delineate the “Nebo North” VOC groundwater plume source area and define subsurface conditions. Modified the preliminary remedial design using the updated conceptual site model, and constructed an air sparge/soil vapor extraction (AS/SVE) system to treat soil and groundwater within the source area. Provided O&M and long-term monitoring (LTM) of four active remedial systems and four drinking water GAC treatment systems; monitoring/reporting on five distinct groundwater plumes including two with off-site components. Project highlights include:
- Innovatively designed and performed the first Multiple Increment Sampling program at a small arms firing range in California
- Saved $750K through value engineering to redesign and optimize two 10-yr old AS/SVE systems that dropped concentrations to below maximum contaminant levels (MCLs) within 2 years and led to FFA approval of shutdown evaluations
- Managed task orders at a complex site successfully improving system uptimes from 50% to 95%, leading to site closure
- Reduced overall costs by 22% through optimization measures and an Integrated Maintenance Plan for non-routine repairs.
- Met Nebo North TCE/PCE plume source area remediation remedial action objectives and shrunk plume by more than 50%; system was shut down and LTM program reduced with cost savings estimated at $55,925 annually.