Drycleaner Site Profiles

Toni's Cleaners, Boca Raton, Florida

Description
Historical activity that resulted in contamination.

Toni's Cleaners is an active PCE drycleaning facility that has been operating since 1993. The facility is located in a shopping center in a mixed commercial retail/residential setting. The contaminant source area identified during the site assessment was a storm water drain located just outside the service door of the drycleaning facility. High concentrations of PCE, TCE and cis 1,2-DCE were detected in sediments/soils, in the drain which receives stormwater and is connected to perforated piping to allow for infiltration into the ground(French drain system, or soakage pit).

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


Contaminant Media Concentration (ppb) Nondetect
cis-1,2-Dichloroethene groundwater 130 ppb
cis-1,2-Dichloroethene soil 470,000 ppb
1,1-Dichloroethene groundwater 3 ppb
Tetrachloroethene (PCE) groundwater 359 ppb
Tetrachloroethene (PCE) soil 1,500,000 ppb
Trichloroethene (TCE) groundwater 35 ppb
Trichloroethene (TCE) soil 1,300,000 ppb
trans-1,2-Dichloroethene groundwater 6 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:   45ft bgs
Plume Size:   Plume Length: 65ft
Plume Width: 180ft
Average Depth to Groundwater:   9ft

Lithology and Subsurface Geology

 
  fine-grained silica sands, some carbonate sand and limestone gravel

Conductivity: 37.5ft/day
Gradient: 0.0015ft/ft

Pathways and DNAPL Presence

checkGroundwater
checkSediments
checkSoil
DNAPL Present

Remediation Scenario

Cleanup Goals:
  Soil: PCE & TCE = 30 µg/kg, cis 1,2-DCE = 400 µg/kg

Groundwater: PCE & TCE = 3.0 µg/L, cis 1,2-DCE = 70 µg/L, trans 1,2-DCE = 100 µg/L, 1,1-DCE = 7.0 µg/L

Technologies

In Situ Monitored Natural Attenuation
 

Why the technology was selected:
Monitored natural attenuation was selected as the groundwater remedy because, contaminant concentrations in groundwater were relatively low; the contaminant plume had not migrated off property; and reductive dechlorination was occurring in groundwater.

Ex Situ Soil Removal
 

Why the technology was selected:
Removal (excavation) was selected as the soil/sediment remedy at the site, because contaminated soil/sediment was accessible.

Date implemented:
May 7, 1998

Final remediation design:
Sediments/Soil was hand-excavated from the storm drain and then the storm drain was steam cleaned.

Results to date:
Two 55-gallon drums of sediment/wastewater were generated during the excavation/steamcleaning. PCE concentrations in groundwater samples collected from two source area monitoring wells prior to the removal were 260 and 120 µg/L respectively. A groundwater monitoring event conducted in February 1999, found PCE concentrations of 7.9 and 2.8 µg/L in the same two source area monitoring wells. Groundwater monitoring continued for three years after sediment/soil removal until contaminant concentrations in monitoring well groundwater samples were below cleanup target levels in two consecutive sampling events. A Site Rehabilitation Completion Order was issued for the site on July 27, 2001.

Cost to Design and Implement:
$8000 (sediment removal and disposal)

Costs

Cost for Assessment:
  $73,700
Cost for Operation and Maintenance:
  $39,800 (groundwater monitoring) $5,400 (site restoration)
Total Costs for Cleanup:
  $126,900

Lessons Learned

1. If the contaminant source area is accessible, source removal (excavation) can be an effective remedial method and, coupled with monitored natural attenuation, may be an effective means for closing sites with limited groundwater contamination.

Contacts

Aaron Cohen, Project Manager
Bureau of Waste Cleanup (MS4520)
Florida Department of Environmental Protection
2600 Blair Stone Road
Tallahassee, Florida 32399-2400
Phone: (850) 245-8962
e-mail: Aaron.Cohen@dep.state.fl.us

Contractor:
Bruce Wilson, PG
Ecology & Environment
1950 Commonwealth Lane
Tallahassee, Florida 323303
Phone: (850) 574-1400
Bwilson@ene.com

Site Specific References

1. Contamination Assessment Report - November 1997
2. Groundwater Monitoring Reports 1999 - 2001