Final Restoration Complete at the Landfill Ridge
The landfill ridge was selected as the first area to be remediated because the soils in this area were the least contaminated. In 2014, pre-design work for excavation of the landfill ridge areas began when geologists took deep soil borings around the 1.8 acre area to determine where site contaminants were present that exceeded the criteria established by the Maine DEP. Between July and September 2015, geologists conducted an additional 97 geotechnical soil borings that confirmed mercury was the only contaminant that exceeded the site clean-up criteria.
This information was used to prepare a detailed design plan or Corrective Measures Implementation (CMI) Plan, which outlined how the soil was to be excavated, where it would be transported and disposed and how the area was to be restored. The Maine DEP approved this plan in December 2015 and Envirocon was selected as the contractor to complete this work.
Soils that exceeded the clean-up standard for mercury were excavated and loaded into rail cars and shipped to a secure landfill in New York for permanent containment.
After completing the excavation of contaminated soil from the area, engineers returned in 2018 to install storm water management systems and regrade the newly restored slope. After seeding the new soil, watering crews spent the spring and early summer bringing vegetation back to the area to complete the restoration and recovery process.
Full copy is available at the Public repository located at: Orrington Town library - 15 School Street, Orrington, ME 04474
The Final Construction Closure report for the Landfill Ridge remediation was submitted to the Maine DEP on February 3, 2017. Maine DEP determined the report to be complete in a letter dated August 21, 2017.