Drycleaner Site Profiles

Cedarburg Drycleaners, Cedarburg, Wisconsin

Description
Historical activity that resulted in contamination.

The Cedarburg Dry Cleaners is an active facility that has operated in a mixed commercial and residential area since about 1968. The drycleaner has used perchloroethylene (PCE), and investigations revealed the presence of PCE in soil and PCE and its breakdown products in groundwater. One source of contamination was the illegal disposal of solvents on-site. The investigation results also suggest that a one-time spill inside the facility, the release of PCE through floor drains, and the temporary placement of filters in the grass behind the facility also contributed to soil and groundwater contamination. Contamination has migrated off-site, but has not impacted drinking water wells.

Contaminants
Contaminants present and the highest amount detected in both soil and groundwater.


Contaminant Media Concentration (ppb) Nondetect
1,1-Dichloroethene groundwater 1,000 ppb
Tetrachloroethene (PCE) groundwater 6,800 ppb
Tetrachloroethene (PCE) soil 21,000 ppb
Trichloroethene (TCE) groundwater 810 ppb
Trichloroethene (TCE) soil 300 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:   30ft bgs
Plume Size:   Plume Length: 165ft
Plume Width: 70ft
Average Depth to Groundwater:   4ft

Lithology and Subsurface Geology

 
  Somewhat poorly drained, dark brown silty clay topsoil and fill with occasional sand and gravel
Depth: 1-4ft bgs
3ft thick
Conductivity: 0.03ft/day
Gradient: 0.045ft/ft
 
  Brown and gray silty clays and clayey silts
Depth: 4-16ft bgs
12ft thick
Conductivity: 0.03ft/day
 
  Grey silty clay with a trace of sand and gravel and some discontinuous seams
Depth: 15-39ft bgs
24ft thick
Conductivity: 0.03ft/day
 
  Silty fine sands
Depth: 39ft bgs
Conductivity: 28ft/day

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkDNAPL Present

Remediation Scenario

Cleanup Goals:
  Restore the contaminated soil and groundwater, to the extent practicable, and minimize the potential risks associated with the contamination in accordance with WI state spill law, Chapter NR 700. Treated soils returned to the excavation site must contain PCE concentrations below the WI Admin. Code, Chapter NR 600 Land Disposal Restriction limit of 6 mg/kg.

Technologies

In Situ Bioremediation
 

Final remediation design:
To treat contaminated groundwater, contractors injected dilute molasses solution using three different methods (in situ forced air desorption process, temporary Geoprobe injection wells, and an infiltration gallery) to create an in-situ reaction zone. This organic carbon source creates anaerobic and strong reducing conditions within the zone, enhancing reductive dechlorination of chlorinated contaminants.

Results to date:
Soil: Synthetic Precipitation Leaching Procedure (SPLP) test results indicated that PCE concentrations were within the site-specific residual contaminant level (RCL) of 390 µg/kg.

Next Steps:
Contractors are monitoring the groundwater for VOCs and natural attenuation parameters on a semiannual basis for a total of two years. These results will determine the next steps at the site.

Cost to Design and Implement:
Total costs for all technologies: Soil: $216,153; Groundwater: $132,108; Laboratory: 57,445; Miscellaneous: $8,588 (These are reimbursed costs. Another $34,679 was spent on site investigation and remediation that was not reimbursed.)

In Situ Soil Vapor Extraction
 

Final remediation design:
Contractors used a Mobile Injection Treatment Unit (MITU) to treat about 3,000 cubic yards of VOC-contaminated soil in two source areas. The MITU process uses a chain trencher to break up and pulverize the soil matrix, At the same time, hot air at temperatures up to 700°F is forced into the trench and across the fine soil particles. The combination of soil agitation and pulverization with forced hot air movement across soil particles results in an efficient, thermally-enhanced volatilization of VOCs present.

Results to date:
Soil: Synthetic Precipitation Leaching Procedure (SPLP) test results indicated that PCE concentrations were within the site-specific residual contaminant level (RCL) of 390 µg/kg.

Cost to Design and Implement:
Total costs for all technologies: Soil: $216,153; Groundwater: $132,108; Laboratory: 57,445; Miscellaneous: $8,588 (These are reimbursed costs. Another $34,679 was spent on site investigation and remediation that was not reimbursed.)

Costs

Cost for Assessment:
  Soil: $18,336; Groundwater: $54,251
Cost for Operation and Maintenance:
 
Total Costs for Cleanup:
  $486,680 (includes reimbursed and deductible costs). Site closed in 2005.

Lessons Learned

1. The size of the equipment limited the success of the MITU. The technology itself was successful, but the trencher could not penetrate deep enough. The machine size was not suited to the site.

Contacts

Scott Ferguson
Hydrogeologist Remediation and Redevelopment, Milwaukee Service Center
WI Department of Natural Resources
2300 N. Martin Luther King Jr. Dr.
PO Box 12436
Milwaukee, WI 53212
414-263-8685
Fergus@dnr.state.wi.us

Contractors:
Key Environmental Services
W66 N215 Commerce Court
Cedarburg, WI
414-375-4750

Jim Drought
ARCADIS Geraghty & Miller, Inc.
126 North Jefferson Street, Suite 400
Milwaukee, WI 53202
414-276-7742