Drycleaner Site Profiles

Venetian Cleaners, Venice, Florida

Description
Historical activity that resulted in contamination.

PCE drycleaning operations were performed at this facility from January 1963 until November 1991 when it was converted to a dry drop off facility that operated until 1995. The site is located in a shopping center in a mixed retail commercial/residential setting. The shopping center is located approximately 0.8 mile northeast of the Gulf of Mexico and 1,200 feet southwest of the Intracoastal Waterway.

Remediation Status: Site closed


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


Contaminant Media Concentration (ppb) Nondetect
cis-1,2-Dichloroethene groundwater
Tetrachloroethene (PCE) groundwater
Tetrachloroethene (PCE) soil
Trichloroethene (TCE) groundwater

Site Hydrology

Deepest Significant Groundwater Contamination:   14ft bgs
Plume Size:   Plume Length: 340ft
Plume Width: 160ft
Plume Thickness: 14ft
Average Depth to Groundwater:   7.43ft

Lithology and Subsurface Geology

 
  fine to medium-grained sand
Depth: 0-19.5ft bgs
19.5ft thick
Conductivity: 37.5ft/day
Gradient: 0.005ft/ft
 
  clayey fine to medium-grained sand
Depth: 19.5-21.5ft bgs
2ft thick
 
  fine-grained sand with shells and traces of clay and phosphate nodules
Depth: 21.5-33ft bgs
11.5ft thick
 
  fine to medium-grained sand with shells and phosphate
Depth: 33-39ft bgs
6ft thick

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
DNAPL Present

Vapor Intrusion Pathway

Has the potential for vapor intrusion (VI) been evaluated?
  No
Has a vapor mitigation system been installed?
  Yes 
Type of Vapor Mitigation System(s):
  Soil Vapor Extraction

Remediation Scenario

Cleanup Goals:
  Soil: PCE = 30 ug/kg (leachability)]
Groundwater: PCE = 3 ug/l, TCE = 3 ug/l, Cis 1,2-DCE = 70 ug/l
Remedy Level:
  Full Scale Remedy

Technologies

In Situ Monitored Natural Attenuation
 

Why the technology was selected:
Monitored natural attenuation was chosen as the groundwater remedy due to the low contaminant concentrations in groundwater, the presence of PCE daughter products as evidence that reductive dechlorination was an active process and the limited depth of groundwater contamination.

Date implemented:
February 12, 2008

Cost to Design and Implement:
all technologies: $49,400

In Situ Soil Vapor Extraction
 

Why the technology was selected:
Soil vapor extraction is an effective technology for removing VOCs from permeable unsaturated sediments.

Date implemented:
February 12, 2008

Final remediation design:
The SVE system consists of ten (10) vertical vapor extraction wells screened 1-5 ft BLS. These wells are constructed of 2-inch diameter Schedule 40 PVC and were installed via hand auger. Six (6) of the vapor recovery wells were installed beneath the floor slab of the bay that formerly housed the drycleaning operation. The remaining four (4) vapor extraction wells were installed in the area behind the facility (delivery area and exit route for the sanitary sewer line. The system is powered by a 5 HP Rotron regenerative blower. The system also has a 1 HP Rotron regenerative blower utilized for air injection to increase the efficiency of the treatment system by eliminating potential dead zones in the flow patterns produced by the SVE system during normal operation. Off gas is treated by a 170 lb. vapor phase G.A.C. vessel. Minimum design flow rate is 108 scfm and 70 inches of water column. The system is designed to run in two zones: the six wells installed under the facility and the four wells installed behind the facility. Each zone will operate 12 hours per day.

Results to date:
The SVE system was turned off in January 2009. Confirmatory soil samples collectedin April 2009 indicated some residual PCE mass was still present in soil and the system was re-started in May. The SVE system was shut down on September 15, 2009. Confirmatory soil sampling found no contaminant concentrations exceeding any soil cleanup target level. No contaminants were detected in groundwater sample collected in four (4) consecutive groundwater monitoring events conducted over the next year. On April 8, 2011 a Site Rehabilitation Completion Order was issued for the site.

Cost to Design and Implement:
all technologies: $49,400

Ex Situ Carbon Adsorption
 

Date implemented:
February 12, 2008

Final remediation design:
The SVE system consists of ten (10) vertical vapor extraction wells screened 1-5 ft BLS. These wells are constructed of 2-inch diameter Schedule 40 PVC and were installed via hand auger. Six (6) of the vapor recovery wells were installed beneath the floor slab of the bay that formerly housed the drycleaning operation. The remaining four (4) vapor extraction wells were installed in the area behind the facility (delivery area and exit route for the sanitary sewer line. The system is powered by a 5 HP Rotron regenerative blower. The system also has a 1 HP Rotron regenerative blower utilized for air injection to increase the efficiency of the treatment system by eliminating potential dead zones in the flow patterns produced by the SVE system during normal operation. Off gas is treated by a 170 lb. vapor phase G.A.C. vessel. Minimum design flow rate is 108 scfm and 70 inches of water column. The system is designed to run in two zones: the six wells installed under the facility and the four wells installed behind the facility. Each zone will operate 12 hours per day.

Results to date:
The SVE system was turned off in January 2009. Confirmatory soil samples collectedin April 2009 indicated some residual PCE mass was still present in soil and the system was re-started in May. The SVE system was shut down on September 15, 2009. Confirmatory soil sampling found no contaminant concentrations exceeding any soil cleanup target level. No contaminants were detected in groundwater sample collected in four (4) consecutive groundwater monitoring events conducted over the next year. On April 8, 2011 a Site Rehabilitation Completion Order was issued for the site.

Cost to Design and Implement:
all technologies: $49,400

Costs

Cost for Assessment:
  $52,300
Cost for Operation and Maintenance:
  $57,500
Total Costs for Cleanup:
  $209,500

Lessons Learned

Based on work conducted at over 300 Florida drycleaning sites, it appears that approximatley 28% of these sites can be closed solely by soil (unsaturated zone) remediation.

Contacts

Stacie Davis, Project Manager
Bureau of Waste Cleanp
Florida Dept. of Environmental Protection (MS4520)
2600 Blair Stone Road
Tallahassee, Florida 32399-2400
Phone: (850) 245-8967
Stacie.A.Davis@dep.state.fl

Brian Moore, PE, Consultant
H.S.A. Engineers & Scientists
4019 East Fowler Avenue
Tampa, Florida 33617
Phone: (813) 971-3882
Bmoore@hsa-env.com

Site Specific References

Site Assessment Report: April 2006
Remedial Action Plan: July 2006
Construction Completion Report: March 2008
Operation & Maintenance Reports: 2008
Groundwater Monitoring Reports: 2009 - 2010