Drycleaner Site Profiles

French Cleaners, Deerfield Beach, Florida

Description
Historical activity that resulted in contamination.

French Cleaners is an active PCE drycleaning facility that has been in operation since the mid 1980s. The facility is located in a strip mall in a mixed retail-commercial setting. The contaminant source area was the soil beneath the facility floor slab in the vicinity of the drycleaning machine and a floor drain. The drycleaning facility is located within the wellhead protection area of the city wellfield. The nearest water supply well is located 150 feet south of the drycleaning facility. This well produces from a zone 66-87 feet BGS. Four other water supply wells are located within 1000 feet of the facility.

Remediation Status: Site closed


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


Contaminant Media Concentration (ppb) Nondetect
Tetrachloroethene (PCE) groundwater 270 ppb
Tetrachloroethene (PCE) soil 160 ppb
Trichloroethene (TCE) soil 2.9 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:  
Plume Size:   Plume Length: 65ft
Plume Width: 50ft
Plume Thickness: 10ft
Average Depth to Groundwater:   9ft

Lithology and Subsurface Geology

 
  fine-grained sand
Depth: 0-9ft bgs
9ft thick
Conductivity: 16.54ft/day
Gradient: 0.001ft/ft
 
  very fine to fine-grained sand
Depth: 9-14ft bgs
5ft thick
 
  fine to coarse-grained sand with shells
Depth: 14-16ft bgs
2ft thick
 
  fine-grained sand
Depth: 16-18ft bgs
2ft thick
 
  silty, very fine to fine-grained sand with shells, minor clay
Depth: 18-39ft bgs
21ft thick
 
  limestone with fine-grained sand & shells
Depth: 39-43ft bgs
4ft 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

Groundwater: PCE = 3 ug/l, TCE = 3 ug/l

Remedy Level:
  Full Scale Remedy

Technologies

In Situ Soil Vapor Extraction
 

Why the technology was selected:
Soil was composed permeable sediments (fine-grained sand) and the water table was relatively deep (9 ft BGS). SVE is an effective technology for remvoving VOCs from permeable, unsaturated sediments.

Date implemented:
September 20, 2006.

Final remediation design:
The SVE system consists of two vertical vapor extraction wells constructed of 4-inch diameter Schedule 40 PVC screened from 1-6 ft beneath the facility floor slab with 0.020-inch slotted screen. Both vapor extraction wells were installed beneath the facility floor slab near the drycleaning machine and the floor drain. Four vapor monitoring wells were installed (constructed of 2-inch diameter Schedule 40 PVC and screened 1-6 feet). Three of these wells were installed beneath the facility floor slab and the fourth well was installed outside the service door of the facility. The system is powered by a 2 HP regenerative Rotron blower. Off gas is treated in a 170-lb. G.A.C. unit. The system was desinged to operate at an average wellhead vacuum pressure of 21 inches w.c. at an average flow rate of 23 scfm per SVE well. The average radius of influence of the two vapor extraction wells was 15 and 20 feet.

Results to date:
SVE system shut down on March 8, 2007 after five and one half months of operation. Confirmatory soil samples showed that the soil cleanup target levels had been met. Groundwater contaminant concentrations dropped below cleanup target levels after the September 8, 2007 monitoring event.

Next Steps:
A Site Rehabilitation Completion Order was issued for this site on April 25, 2008.

Cost to Design and Implement:
Design: $10,600 Implementation: $106,400

Ex Situ Carbon Adsorption
 

Date implemented:
September 20, 2006.

Final remediation design:
The SVE system consists of two vertical vapor extraction wells constructed of 4-inch diameter Schedule 40 PVC screened from 1-6 ft beneath the facility floor slab with 0.020-inch slotted screen. Both vapor extraction wells were installed beneath the facility floor slab near the drycleaning machine and the floor drain. Four vapor monitoring wells were installed (constructed of 2-inch diameter Schedule 40 PVC and screened 1-6 feet). Three of these wells were installed beneath the facility floor slab and the fourth well was installed outside the service door of the facility. The system is powered by a 2 HP regenerative Rotron blower. Off gas is treated in a 170-lb. G.A.C. unit. The system was desinged to operate at an average wellhead vacuum pressure of 21 inches w.c. at an average flow rate of 23 scfm per SVE well. The average radius of influence of the two vapor extraction wells was 15 and 20 feet.

Results to date:
SVE system shut down on March 8, 2007 after five and one half months of operation. Confirmatory soil samples showed that the soil cleanup target levels had been met. Groundwater contaminant concentrations dropped below cleanup target levels after the September 8, 2007 monitoring event.

Next Steps:
A Site Rehabilitation Completion Order was issued for this site on April 25, 2008.

Cost to Design and Implement:
Design: $10,600 Implementation: $106,400

Costs

Cost for Assessment:
  $62,700
Cost for Operation and Maintenance:
  $41,900
Total Costs for Cleanup:
  $221,700

Lessons Learned

1. Prior to application of the facility to the Drycleaning Solvent Cleanup Program, a sentinel well had downgradient of the drycleaning facility as part of the wellhead protection plan. This well had never produced a groundwater sample with detectable concentrations of PCE or PCE degradation products. However, asessment work showed that this this well was not located directly downgradient of the contaminant source area (drycleaning machine).

Contacts

Theresa.Pepe, Project Manager
Bureau of Waste Cleanup (MS4520)
Florida Department of Environmental Protection
2600 Blair Stone Road
Tallahassee, Florida 32399-2400
phone: (850) 245-8966
e-mail: Theresa.Pepe@dep.state.fl.us

Bill Vogelsong, PG, consultant
ARCADIS Geraghty & Miller, Inc.
712 US Highway One, Suite 200
North Palm Beach, Florida 33408
phone: (561) 697-7000

Site Specific References

Site Assessment Report: 2004
Remedial Action Plan: September 2005
Remedial Action System Startup Report: October 2006

Operation & Maintenance Reports: 2006-2007

Post-Active Remedial Monitoring Reports: 2007 - 2008