The Landfill 1 Area is located west of the manufacturing area. There were two discrete disposal areas used as well as a surface impoundment for wastewater. This area was closed and capped with a plastic (Hypalon) material in approximately 1980.

 
Mallinckrodt worked with the Maine DEP to finalize the Corrective Measures Implementation (CMI) Plan  that details the design of the remediation. The area adjacent to the former landfill area slopes steeply down to the River so health and safety and erosion controls measures were an important factor in the design.

 
New England-based environmental firm Charter Environmental was chosen to conduct this phase of site remediation. Charter’s experience with high-profile Maine projects, such as the Callahan Mine Superfund Site Remedial Action in Brooksville, and the Casco Bay Pipeline Remediation in Brunswick, was an important factor in their selection for the Orrington project.

The remediation of Landfill 1 began in 2018 and consisted of excavating certain soils with mercury concentrations above the Media Protection Standards. Soil samples were collected during the remediation process to confirm that the design criteria was being met and excavated soils were then transported off site for disposal in secure landfills. Over 1,620 pre-design and post-excavation samples collected from this area showed the remediation was successfully completed.

After completion of the excavation work, the area was backfilled, graded and restored with vegetation similar to the restoration work that was completed at the Landfill Ridge. A total of 86,618 tons of soil were removed from the Landfill 1 area, the Construction Closure Report was submitted, and Maine DEP issued a conditional closure letter for this area in 2018.
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