1907 -1947 - The City of Webster City, IA owns and operates a coal gasification plant. The Plant, located near the Boone River and the old city pond, is similar to many being operated across the state during that period. The plant converts coal into gas for heating and lighting. Common practice at the time includes dumping of coal tar residue on bare ground. The estimated start-up date for the plant is around 1916.

 1987 - Frigidaire submits site investigation report summarizing remedial investigation work and assessment to Iowa Department of Natural Resources and U.S. Environmental Protection Agency.

 1992 - The City of Webster City and Frigidaire enter into a consent order with the DNR to investigate potential contamination.

 1/1993 - Barr Engineering is hired by the city and Frigidaire to conduct an assessment of the site.

 3/1993 - Preliminary findings discover that there is coal tar residue 10 to 15 feet below the soil surface and below the Boone River bed, but no measurable quantities are found either on the surface or in the river.

 7/1993 - Both Frigidaire and the City of Webster City agree to cost-sharing to fund the clean-up efforts.

 9/1993 - 10/1993 - Iowa Department of Natural Resources approves a proposal to install extraction wells to pump contaminants from the groundwater and a hydraulic containment system to prevent contaminants from entering the river.

 1/1995 - The site is now online. Coal Tar residue will be pumped from recovery wells to a containment facility located at the edge of the site. The hydraulic containment system will pump groundwater water (containing small amounts of contaminants) into the containment facility where it will run through a series of two Granulated Activated Carbon filters to clean up any contamination.

 1/1996 - Barr Engineering is named a winner in the Seven Wonders of Engineering awards program by the Minnesota Society of Professional Engineers. The project is praised for its unique partnering of a municipal government, private enterprise and a state regulatory agency. Working together, and through the professional assistance of Barr Engineering, the effort is credited with lowering clean-up costs by as much as $10 million because the site has avoided being named to the EPA's Superfund list.