Drycleaner Site Profiles

TLC Dry Cleaners, Miami, Florida

Description
Historical activity that resulted in contamination.

TLC Cleaners is an active PCE drycleaning facility that has been in operation since approximatley 1970. The facility is served by a septic tank/drainfield. Chlorinated solvents had been detected in wastewater samples collected from the septic tank on several occasions prior to the commencement of assessment work by the Florida Drycleaning Solvent Cleanup Program and the septic tank had been pumped out and steam cleaned several times. The facility is located in a shopping center in a mixed retail commercial/residential setting. The identified contaminant source areas are the soil beneath the facility floor slab, the area outside the service door and the septic tank/drainfield

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
1,1-Dichloroethene groundwater
Tetrachloroethene (PCE) groundwater
Tetrachloroethene (PCE) soil
Trichloroethene (TCE) groundwater
Trichloroethene (TCE) soil
toluene groundwater
trans-1,2-Dichloroethene groundwater
Vinyl Chloride groundwater
m-Xylene soil

Site Hydrology

Deepest Significant Groundwater Contamination:   40ft bgs
Plume Size:   Plume Length: 215ft
Plume Width: 165ft
Plume Thickness: 30ft
Average Depth to Groundwater:   9.06ft

Lithology and Subsurface Geology

 
  fine to medium-grained sand interbedded with sandy gravel and sandstone
Depth: 0-6ft bgs
6ft thick
Conductivity: 22ft/day
Gradient: 0.0025ft/ft
 
  oolitic limestone
Depth: 6-20ft bgs
14ft thick
 
  very fine-grained to fine-grained sand with shells
Depth: 20-48ft bgs
28ft thick
 
  fossiliferous limestone
Depth: 48-54ft bgs
6ft thick

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkDNAPL 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
Additional VI Information:
  Contaminated soil excavated outside service door.

Remediation Scenario

Cleanup Goals:
  Groundwater: PCE = 3 ug/l, TCE = 3 ug/l, cis 1,2-DCE = 70 ug/l, vinyl chloride 1 ug/l

Soil: PCE = 30 ug/kg; TCE = 30 ug/kg (leachability)
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 because reductive dechlorination was an active process, and it was believed that addressing soil contamination by excavation and soil vapor extraction would result in a large reduction in contaminant concentrations in groundwater.

Next Steps:
This site has met No Further Action conditions (without institutional and engineering controls). A Site Rehabilitation Completion Order will be issued for the site.

Cost to Design and Implement:
Design: $14,400 Excavation: $2,900 SVE Install & Startup: $54,200

In Situ Soil Vapor Extraction
 

Why the technology was selected:
Soil vapor extraction was selected because it is an effective technology for remediating permeable soils contaminated with VOCs.

Date implemented:
Soil Vapor Extraction: August 26, 2003

Final remediation design:
The soil vapor extraction system consisted of nine vapor extraction wells screened 1-5 feet below grade. Six of these wells were installed beneath the floor slab of the drycleaning facility and three of the wells were installed outside the back of the building that housed the drycleaning operation. The system is powered by a 10 HP Rotron regenerative blower. Design flow rate is 260 cfm A 3 HP Rotron regenerative blower was utilized for air injection. Off gas is treated via a 200 lb. G.A.C. vessel.

Results to date:
On April 10, 2002 approximately 7.3 cubic feet of soil was excavated from the area outside the service door of the facility. All nine (9) wells were utilized for vapor recovery for the first 36 days of operation of the SVE system. After that 4 wells were utilized for vapor recovery with 4 wells off and then the remaining 5 wells were used for vapor recoveyr wells with 4 wells off. Finally, air was injected into five wells and four wells were used for vapor recovery and then air injection wells were used for vapor recovery and air was injected into the wells that had been used for vapor recovery. This was done to increase wellhead vacuum, increase the system radius of influence, eliminate dead zones and to change change air flow paths to maximize system recovery and efficiency. The Soil vapor extraction system was turned off in June 2004 after ten months of operation. Confirmatory soil samples showed that soil has been remediated to below cleanup target levels. No contaminants have been detected in groundwater samples collected during the last two groundwater monitoring events conducted in 2009.

Next Steps:
This site has met No Further Action conditions (without institutional and engineering controls). A Site Rehabilitation Completion Order will be issued for the site.

Cost to Design and Implement:
Design: $14,400 Excavation: $2,900 SVE Install & Startup: $54,200

Ex Situ Carbon Adsorption
 

Date implemented:
Soil Vapor Extraction: August 26, 2003

Final remediation design:
The soil vapor extraction system consisted of nine vapor extraction wells screened 1-5 feet below grade. Six of these wells were installed beneath the floor slab of the drycleaning facility and three of the wells were installed outside the back of the building that housed the drycleaning operation. The system is powered by a 10 HP Rotron regenerative blower. Design flow rate is 260 cfm A 3 HP Rotron regenerative blower was utilized for air injection. Off gas is treated via a 200 lb. G.A.C. vessel.

Results to date:
On April 10, 2002 approximately 7.3 cubic feet of soil was excavated from the area outside the service door of the facility. All nine (9) wells were utilized for vapor recovery for the first 36 days of operation of the SVE system. After that 4 wells were utilized for vapor recovery with 4 wells off and then the remaining 5 wells were used for vapor recoveyr wells with 4 wells off. Finally, air was injected into five wells and four wells were used for vapor recovery and then air injection wells were used for vapor recovery and air was injected into the wells that had been used for vapor recovery. This was done to increase wellhead vacuum, increase the system radius of influence, eliminate dead zones and to change change air flow paths to maximize system recovery and efficiency. The Soil vapor extraction system was turned off in June 2004 after ten months of operation. Confirmatory soil samples showed that soil has been remediated to below cleanup target levels. No contaminants have been detected in groundwater samples collected during the last two groundwater monitoring events conducted in 2009.

Next Steps:
This site has met No Further Action conditions (without institutional and engineering controls). A Site Rehabilitation Completion Order will be issued for the site.

Cost to Design and Implement:
Design: $14,400 Excavation: $2,900 SVE Install & Startup: $54,200

Ex Situ Soil Removal
 

Why the technology was selected:
Excavation was selected because there was a shallow groundwater table and contaminated soils were accessible.

Date implemented:
Excavation: April 10, 2002 Soil Vapor Extraction: August 26, 2003

Results to date:
On April 10, 2002 approximately 7.3 cubic feet of soil was excavated from the area outside the service door of the facility. All nine (9) wells were utilized for vapor recovery for the first 36 days of operation of the SVE system. After that 4 wells were utilized for vapor recovery with 4 wells off and then the remaining 5 wells were used for vapor recoveyr wells with 4 wells off. Finally, air was injected into five wells and four wells were used for vapor recovery and then air injection wells were used for vapor recovery and air was injected into the wells that had been used for vapor recovery. This was done to increase wellhead vacuum, increase the system radius of influence, eliminate dead zones and to change change air flow paths to maximize system recovery and efficiency. The Soil vapor extraction system was turned off in June 2004 after ten months of operation. Confirmatory soil samples showed that soil has been remediated to below cleanup target levels. No contaminants have been detected in groundwater samples collected during the last two groundwater monitoring events conducted in 2009.

Next Steps:
This site has met No Further Action conditions (without institutional and engineering controls). A Site Rehabilitation Completion Order will be issued for the site.

Cost to Design and Implement:
Design: $14,400 Excavation: $2,900 SVE Install & Startup: $54,200

Costs

Cost for Assessment:
  $129,800
Cost for Operation and Maintenance:
  Operation & maintenance: $34,200 Monitoring: $45,200 Site Restoration: $5,000
Total Costs for Cleanup:
  $285,700

Lessons Learned

Utilizing air injection and switching wells from vapor recovery to air injection was successful in optimizing SVE system recovery.

Contacts

Stacie Davis, Project Manager
Bureau of Waste Cleanup (MS4520)
Florida Department of Environmental Protection
2600 Blair Stone Road
Tallahassee, Florida 32399-2400

Phone: (850) 245-8967
Stacie.Davis@dep.state.fl.us

Brian Moore, PE
H.S.A. Engineers & Scientists
4019 East Fowler Avenue
Tampa,Florida 33617

Phone: (813) 971-3882
E-Mail: bmoore@hsa-env.com

Site Specific References

Contamination Assessment Report: January 2000

Remedial Action Plan: May 2002

Interim Source Removal Report: May 2002

SVE System Construction Completion Report: October 2003

O&M Reports: 2003 - 2004

Monitoring Reports: 2001 - 2009