Electroosmosis,
Appleton, WI

Remedial investigation/treatment of contaminated soils and groundwater from a 500-gallon leaded gasoline underground storage tank. A SESOIL model simulation was performed to determine the levels of contamination that could remain without adversely impacting the groundwater. Contaminated soils were excavated in the location of an ongoing building expansion. Horizontal wells were installed under the existing building to promote groundwater extraction and infiltration of inaccessible soils and groundwater. Recovery wells were installed under the building addition using a unique jet pump system to allow maintenance free recovery under the new building addition. Solar panels supplied DC power to a series of six electrodes. These electrodes drove contaminated water through a collection trench for recovery.

Electroosmosis was used at this site to treat approximately 1000 tons of soil. It increased water movement through low permeable soils by a factor of 10. The solar panels constructed at the site allowed for cost savings over the life of the system and the flexibility to be used at other sites. This site received closure from WDNR and received an honor award from Wisconsin Association of Consulting Engineers.

Midwest Plating Corporation
Appleton, Wisconsin

The Midwest Plating Corporation property is located in a mixed development area. Chrome plating operations began at the facility in 1973. They were directed to conduct an interim action surface soil restoration to restore contaminated soils on their property and three adjacent residential properties. This consisted of removing soils containing concentrations of metals above site-specific residual contaminant levels.

Because the company was financially unable to proceed with the suggested interim action, the WDNR initiated a state-funded response action to address the contaminated soils on residential properties. OMNNI conducted surficial soil sampling to define the degree and extent of soil contamination; prepare and present technical data at public meetings; prepare remedial design plans and specifications for the interim action; prepare bid documents and conduct competitive public bidding; document contaminated soil excavation and replacement with clean fill; oversee construction and contractor work; sample and characterize interim action wastes; determine soil handling, storage, and disposal location requirements; complete confirmation sampling; and document successful completion of the soil restoration project.

OMNNI also provided a topographic survey and prepared a grading plan for the MPC property to redirect surface water away from the site building, to prevent re-contamination of remediated areas in the future.