Project Overview
Waste Management, Inc. retained NTH Consultants Ltd.to develop and implement a work plan for a Remedial Investigation at its solid waste landfill in southwest Michigan. The selection of NTH was based on our firm’s extensive experience at the site, including a hydrogeologic investigation to support the most recent lateral expansion of the landfill in the 1990s, along with continuous groundwater quality monitoring and reporting services since that time.
A groundwater remediation system originally put into operation in 1993 was no longer necessary to control migration of VOCs from a former closed portion of the landfill. The goal of the project was to develop and update the Remedial Action Plan for the site in compliance with current MDEQ Part 201 requirements and shut down the former remediation system.
Project Scope
NTH’s investigation and evaluation included:
- Vertical aquifer sampling down-gradient of remediation system;
- Installation and sampling of strategically placed nested monitoring wells at the site perimeter;
- Sampling nearby residential wells;
- Developing regional background concentrations of naturally-occurring iron and manganese; and
- Defining lateral and vertical extent of residual groundwater impact.
The results of the additional investigation demonstrated that no site-related contaminants have migrated beyond the capture zone of the historic remediation system.
The data from off-site residential wells and on-site up-gradient wells were statistically evaluated to develop representative regional background metals concentrations. The investigation results and evaluation were presented to and approved by the MDEQ Remedial Action Team for consistency with Michigan Part 201 and Part 115 requirements.
Client Benefit
Based on our findings, Waste Management planned to submit a revised and updated Part 201 RAP for the site that will provide effective protection of public groundwater resources and the environment.
