April 11, 2016
6:00 - 7:30 pm
Technical Community College
10915 Hardin Valley Road, Knoxville
J.L Goins Administration Building, Faculty-Staff Dining Room
Groundwater Monitoring Network Maintenance and Modifications at a Subtitle C Landfill
Chemical Waste Management Emelle Facility, Emelle, Alabama
Michael Smilley, P.G.
Golder Associates, Inc.
The Chemical Waste Management Emelle Facility (Facility; Site) is a Subtitle C landfill located in Emelle, Sumter County, Alabama. Hazardous waste is disposed of in disposal cell trenches dug directly into more than 600 feet of relatively impermeable Selma Chalk limestone. In accordance with the facility permit, disposal cells, constructed under very strict U.S. Environmental Protection Agency (EPA) and Alabama Department of Environment Management (ADEM) guidelines, are constructed into the Selma Chalk with double layers of 60 mil High Density Poly Ethylene (HDPE). Additional security measures include a complex leak detection system and sophisticated leachate collection system containing 81 monitoring wells, 6 Resource Conservation Recovery Act (RCRA) compliance wells, and 8 sediment basins to prevent run off. Recent fluctuations in the groundwater flow direction within the deep (>600 feet) RCRA compliance monitoring wells, as measured using depth to water measurements, prompted regulatory concern as the flow vectors varied from the facility permit. A deep monitoring well maintenance plan, involving well seal replacement and well re-development was implemented to evaluate the cause of these fluctuations. During well re-development it was discovered that an obstruction was present in a background monitoring well. The monitoring well was subsequently replaced using mud rotary drilling, with the final well depth being over 600 feet. The strict groundwater analytical requirements of the landfill permit required special precautions be taken during well installation and development. Following installation, regulatory concerns seem alleviated, as the post-maintenance groundwater flow path mirrors the original permit requirements.
Michael Smilley, P.G. is a Senior Project Geologist at Golder Associates. He has over 9 years of experience implementing and managing geological and hydrogeological investigations in the manufacturing, mining, and solid waste sectors. He has performed, evaluated, or optimized site investigations/remediation systems in multiple states in the eastern United States.
Page updated May 26, 2018