Evaluation of a Landfill's Impact on Groundwater, 1993 Environmental Conference Proceedings

Boise Cascade has utilized a company-owned landfill in Mexico, Maine for mill solid waste disposal since the startup of the mill’s wastewater treatment plant in 1976. Due to evidence of leakaae from the landfill’s bentonite-lined leachate pond, a-new leachate pond was installed in the fall of 1987. Several other improvements were made to the landfill’s leachate handling system over the years.

In accordance with the Maine Solid Waste Disposal Regulations, an application was filed to relicense the landfill in March, 1990. Substantial data on groundwater monitoring around the site, along with detailed material handling practices, was presented with the Application. Following extensive review by the Maine Solid Waste Bureau, a two year conditional license was granted by the Bureau in August, 1991, for the Boise Cascade Farrington Mountain landfill. This was the first landfill to be licensed in the state under the new Solid Waste Regulations.

One of the conditions of the permit approval was that Boise must complete an interim groundwater monitoring program, including an assessment of whether landfill wastes are causing contamination of groundwater outside the solid waste boundary. Boise and its consultant developed a proposal for the location of additional monitoring wells both within and outside the solid waste boundary, and procedures for data collection and evaluation. Following the DEP’s approval, the Interim Environmental Monitoring Program was implemented. A site description and evaluation of groundwater flow is presented in this paper, along with the location of the existing and new groundwater monitoring wells. The data collected in the Program thus far is shown, along with the conclusions that can be drawn from the data regarding the landfill impact on groundwater.