15    ASSESSMENT AND REMOVAL OF CHLORINATED
SOLVENTS FROM SOIL AND GROUNDWATER
Steven Fesko, Senior Project Manager
Eaton Corporation
Willoughby Hills, Ohio 44094
BACKGROUND
Eaton Corporation operates a manufacturing facility in a small western Michigan city. Extensive soil and groundwater investigation from 1981 through 1991 showed that historic site practices had impacted the environment. These practices included the release of small volumes of
spent halogenated hydrocarbons directly to the environment. As a result, the Michigan Department of Natural Resources (MDNR) listed the facility on the Act 307 list of contaminated sites
(Michigan equivalent of a Superfund listing). Eaton stopped the use of chlorinated solvents and
removed all source material from the facility.
SUMMARY
The MDNR Act 307 regulation establishes timing and cleanup criteria for contaminated sites.
Normally, companies progress from investigation to remediation following the mandated Act
307 criteria. Eaton, however, teamed with the state agency to conduct a voluntary cleanup and
established site-specific cleanup criteria before any mandated Act 307 requirement. The work
performed under the voluntary plan included a literature search, a review of agency files to compile information on treatment technologies, and an investigation of four alternatives for the removal of contaminants. This review showed a purge well coupled with an air stripper as the least
costly and most effective alternative. Eaton installed and currently operates this type of system.
The treatment system has experienced significant operational problems. These problems arise
from high levels of iron and hardness in the groundwater, resulting in significant equipment scaling and well efficiency loss. Eaton implemented an iron sequestering program coupled with the
addition of a biocide. This program combined with regular acid cleaning has minimized operational problems.
SITE DESCRIPTION
The site contains 35 acres and is located in a mixed residential/light industrial setting. Except
for a depression on the western boundary, the site is relatively flat. The site is bounded on all
sides by private property (see Figure 1). Additionally, the site is covered by a building, surrounding blacktop driveways, a parking lot. and significant open space.
The subsurface geology contains sand, gravel, cobbles with some fines, and occasional zones
of silt and clay. Thickness of this unconsolidated sediment ranges from 41 to 67 feet. The aquifer
is unconfined and starts at 23 feet below ground surface. This unconsolidated zone directly overlays the regional bedrock.
The soils appear to be of fluvioglacial origin based on the site proximity to the river (see Figure 1) and the observed presence of occasional beds of well-sorted sand and/or gravel.
Zones of fines and/or coarse material may influence the movement of contaminants within the
aquifer system. Nested wells show an upward potential between the bedrock and unconsolidated
aquifer. A pump test showed the aquifer had an average specific yield of 6.0% and a hydraulic-
conductivity of 1600 gpd/ft2. The horizonal direction of groundwater flow extends southwest, in
51st Purdue Industrial Waste Conference Proceedings. 1996. Ann Arbor Press. Inc., Chelsea. Michigan 481 18.
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