Drycleaner Site Profiles

Former Foreman's Cleaners, Salem, Oregon

Description
Historical activity that resulted in contamination.

The former Foreman's drycleaners is located in a commercial/residential area in southeast Salem, Oregon. The property was a drycleaner from 1936 to 2001. Operations were discontinued in 2001, and the building was subsequently demolished. Stoddard solvent was used in the drycleaning until the mid-1980's, and PCE was used after that. Drycleaning equipment was located near an exterior door adjacent to the parking lot. Stoddard solvent was stored in a UST. Past spills of drycleaner solvent from equipment to the floor may have flowed out the door and into the gravel parking lot. Still bottom wastes were stored outside this door until 1982. A dry well was found during soil excavation activities. Chlorinated solvents were also found in the sanitary sewer lines. Contaminant source areas were the UST area, drywell, and sanitary sewer lines.

Remediation Status: In groundwater monitoring


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


Contaminant Media Concentration (ppb) Nondetect
sec-butylbenzene groundwater 278 ppb
sec-butylbenzene soil 7,500 ppb
chloroform groundwater 4.1 ppb
cis-1,2-Dichloroethene groundwater 70,000 ppb
cis-1,2-Dichloroethene soil 2,500 ppb
ethylbenzene groundwater 23.1 ppb
ethylbenzene soil 740 ppb
n-butylbenzene groundwater 159 ppb
n-butylbenzene soil 4,600 ppb
Tetrachloroethene (PCE) groundwater 136,000 ppb
Tetrachloroethene (PCE) soil 418,000 ppb
1,2,4-trimethylbenzene groundwater 1,450 ppb
1,2,4-trimethylbenzene soil 5,710 ppb
1,3,5-trimethylbenzene groundwater 430 ppb
1,3,5-trimethylbenzene soil 1,340 ppb
Trichloroethene (TCE) groundwater 36,300 ppb
Trichloroethene (TCE) soil 8,000 ppb
toluene groundwater 14.1 ppb
toluene soil 300 ppb
trans-1,2-Dichloroethene groundwater 720.4 ppb
trans-1,2-Dichloroethene soil 8,000 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:   25ft bgs
Plume Size:   Plume Length: 180ft
Plume Width: 100ft
Plume Thickness: 55ft
Average Depth to Groundwater:   11ft

Lithology and Subsurface Geology

 
  Fill material
Depth: 0-2ft bgs
2ft thick
Gradient: 0.017ft/ft
 
  Gravelly silt
Depth: 2-4ft bgs
2ft thick
 
  layers of clay and silty clay
Depth: 4-61ft bgs
57ft thick

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkDNAPL Present

Remediation Scenario

Cleanup Goals:
  PCE: 14,000 µg/kg

Technologies

Ex Situ Soil Removal
 

Why the technology was selected:
The building was demolished, making it easy to access the source soils and remove them. HRC introduced to enhance degration of the contaminants in groundwater.

Date implemented:
January 14, 2002

Final remediation design:
A trackhoe was used to excavate approximately 477 tons of contaminated soil (soils exceeding 14,000 µg/kg PCE). The excavated area was backfilled with crushed rock ammended with HRC - 1% by weight.

Results to date:
Subsequent groundwater monitoring has shown a significant decrease in PCE and TCE concentrations of up to two orders of magnitude. There has also been a subsequent increase and then decrease in the concentrations of PCE degradation products.

Next Steps:
Continue groundwater monitoring for MNA. Eventually close the site when plume is within risk based levels and demonstrated to be stable and no longer migrating.

Cost to Design and Implement:
$267,000

Costs

Cost for Assessment:
  $150,000
Cost for Operation and Maintenance:
  Monitoring only @ $16,000/year
Total Costs for Cleanup:
 

Lessons Learned

1. Finding the dry well was unexpected and almost doubled the soil excavation and removal costs.

Contacts

Nancy Sawka
Oregon Department of Environmental Quality
750 Front St. N.E. Suite 120
Salem, Oregon 97301

Site Specific References

Focussed Site Investigation Report, June 15, 2000

Removal Assessment and Data Summary Report, April 16, 2001