Drycleaner Site Profiles

Adair Custom Cleaners, Orlando, Florida

Description
Historical activity that resulted in contamination.

This is an active PCE drycleaning facility that has been in operation since 1990. Recently the facility has added an additional drycleaning machine that uses petroleum solvent (DF-2000). The facility is located in a retail commercial/residential setting. The identified contaminant source area at the site is the soil located beneath the facility floor slab in and around the location of the drycleaning machine.

Remediation Status: Site closed


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


Contaminant Media Concentration (ppb) Nondetect
Benzene soil 11.8 ppb
cis-1,2-Dichloroethene soil 11.8 ppb
cis-1,2-Dichloroethene soil 11.8 ppb
1,1-Dichloroethene soil 11.8 ppb
Tetrachloroethene (PCE) soil 11.8 ppb
Tetrachloroethene (PCE) soil 11.8 ppb
Trichloroethene (TCE) soil 11.8 ppb
Trichloroethene (TCE) soil 11.8 ppb
toluene soil 11.8 ppb
Vinyl Chloride soil 11.8 ppb
groundwater 0.42 ppb
soil 7.9 ppb
soil 6.7 ppb
groundwater 0.73 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:   12ft bgs
Plume Size:   Plume Length: 95ft
Plume Width: 80ft
Plume Thickness: 6ft
Average Depth to Groundwater:   7.56ft

Lithology and Subsurface Geology

 
  silty, fine-grained sand
Depth: 0-7ft bgs
7ft thick
Conductivity: 4.12ft/day
Gradient: 0.01ft/ft
 
  silty, clayey, fine-grained sand
Depth: 7-12ft bgs
5ft thick
 
  silty fine-grained sand
Depth: 12-32ft bgs
20ft thick
 
  silty fine-grained sand, minor clay
Depth: 32-36ft bgs
4ft thick
 
  stiff clay
Depth: 36-40ft 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):
  Passive Vapor Barrier
Sub-slab Depressurization
Sub-slab Pressurization
Passive Venting
HVAC controls/modifications
Soil Vapor Extraction

Remediation Scenario

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

Soil: PCE = 30 ug/Kg, TCE = 30 ug/kg, cis 1,2-DCE = 400 ug/Kg, vinyl chloride = 7 ug/Kg
Remedy Level:
  Full Scale Remedy

Technologies

ex Situ Monitored Natural Attenuation
 

Date implemented:
Soil Vapor Extraction: May 10, 2007

ex Situ Soil Vapor Extraction
 

Date implemented:
Soil Vapor Extraction: May 10, 2007

ex Situ Carbon Adsorption
 

Date implemented:
Soil Vapor Extraction: May 10, 2007

in Situ Monitored Natural Attenuation
 

Why the technology was selected:
Monitored natural attenuation was chosen because contaminant concentrations in groundwater were low (16.6 ug/l PCE) and only the very top of the water table had contaminant concentrations exceeding the MCL. Our experience with similar sites is that remediating the soil using SVE will result in the reduction of contaminant concentrations in groundwater to below cleanup target levels.

in Situ Soil Vapor Extraction
 

Why the technology was selected:
Soil vapor extraction was chosen because it is an effective technology for removing VOCs from permeable, unsatured sediments.

Date implemented:
Soil Vapor Extraction: May 10, 2007

Final remediation design:
The SVE system consists of five (5) vertical vapor extraction wells screened 0.5 - 4 ft BLS. All five vapor extraction wells were installed beneath the floor slab of the drycleaning facility.

The system is powered by a 4 HP regenerative blower. Off gas is treated via a 170-lb. G.A.C. vessel. Design operating rate is 80 SCFM.

Results to date:
The SVE system operated from May 2007 through February 2010 and then from May 2010 until January 2011 or approximatley 42 months. Since the shut down of the SVE system, five (5)groundwater monitoring events have been conducted. No contaminants were detected in groundwater samples in concentrations exceeding any cleanup target level and groundwater samples were non-detect for contaminants in the latest groundwater monitoring event conducted in January 2012.

Next Steps:
A Site Rehabilitation Completion Order was issued for the site on April 17, 2012.

Cost to Design and Implement:
Design: $8,200
Implementation: $35,700

Costs

Cost for Assessment:
  $64,300
Cost for Operation and Maintenance:
  O&M: $95,000 Monitoring: $14,800
Total Costs for Cleanup:
  $218,000

Lessons Learned

1. No soil samples had contaminant concentrations exceeding any cleanup target level. However, an active soil gas survey (Modified Active Gas Sampling) found PCE concentrations in soil gas as high as 12 milligrams per cubic meter.

2. A wastewater sample collected from a floor drain at the facility had a total VOC concentration of over 21 mg/L. Contaminants included PCE, TCE, cis 1,2-DCE, trans 1,2-DCE, 1,1-DCE and vinyl chloride - the full range of PCE degradation products, showing that extensive reductive dechlorination can occur before contaminants exit the facility.

3. A monitor well, screened across the water table was installed beneath the facility floor slab near the drycleaning machine. Such a well provides an early warning system for any subsequent discharges at operating drycleaning facilities.

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) 245-8939
E-mail: Anastasia.Davis@dep.state.fl.us

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

Phone: (813) 971-3882
Bmoore@hsa-env.com


Site Specific References

Contamination Assessment Report: 2006
Remedial Action Plan: 2006
Construction Completion Report: 2007
Operation & Maintenance Reports: 2007- 2011
Groundwater Monitoring Reports: 2007 - 2012