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former manufactured gas plant in Michigan

former manufactured gas plant in Michigan
confidential client

obtaining one of the first “de minimis” determinations in Michigan

At the site of a former manufactured gas plant (MGP) near the Kalamazoo River in Michigan, Barr has provided multiple environmental investigation and remediation services. Site characterization indicated that MGP operations and material disposal had left a zone of dense nonaqueous-phase liquid (DNAPL) under and near the river.

Barr determined that removal of the DNAPL would have been excessively expensive and that further investigation would also have been expensive and unsafe. We evaluated groundwater concentrations and flow and concluded that venting groundwater had little effect on the surface water body. Barr presented these findings to the Michigan Department of Environmental Quality, which had recently modified the Part 201 statute (which regulates environmental remediation). The modification allows venting groundwater without response if it can be shown that doing so will only have a “de minimis” (insignificant or of no concern) effect or none at all. While the MDEQ preferred an option that would have required long-term monitoring, Barr explained that the material had been in place for more than 60 years and that our data indicates a stable DNAPL body. Further monitoring would not change the long-term outcome of ongoing minimal impact to the river.

After negotiations with stakeholders and an extension request, MDEQ issued a concurrence letter regarding Barr’s “de minimis” determination for the site. The project received one of the first of these determinations in Michigan. This result provided a substantial savings for our client and allowed them to move forward with site remediation.