Drycleaner Site Profiles

Gold-N-Fluff Cleaners & Coin Laundry, Fort Walton Beach, Florida

Description
Historical activity that resulted in contamination.

PCE drycleaning operations were conducted at the facility from 1970 until 1985. The site is located in a strip mall in a mixed retail commercial/residential setting. The bay of the strip mall formerly occupied by the drycleaning operation is currently utililzed by a laundromat. Two contaminant source areas were found during the site assessment, the soil beneath the floor slab at the former location of the drycleaning machine and the area outside the back door of the facility where wastewater was reportedly discharged.

Remediation Status: In groundwater monitoring


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


Contaminant Media Concentration (ppb) Nondetect
Benzene groundwater
Benzene soil
cis-1,2-Dichloroethene groundwater
cis-1,2-Dichloroethene soil
1,1-Dichloroethene groundwater
Tetrachloroethene (PCE) groundwater
Tetrachloroethene (PCE) soil
Trichloroethene (TCE) groundwater
Trichloroethene (TCE) soil
toluene soil
trans-1,2-Dichloroethene groundwater
trans-1,2-Dichloroethene soil
Vinyl Chloride groundwater

Site Hydrology

Deepest Significant Groundwater Contamination:   60ft bgs
Plume Size:   Plume Length: 580ft
Plume Width: 280ft
Plume Thickness: 56ft
Average Depth to Groundwater:   2.74ft

Lithology and Subsurface Geology

 
  silty, fine-grained sand with organic matter grading to silt with lenses of peat and clay
Depth: 0-3.5ft bgs
3.5ft thick
Conductivity: 8.89ft/day
Gradient: 0.0029ft/ft
 
  fine to medium-grained sand interbedded with silty, fine-grained sand
Depth: 3.5-94ft bgs
90.5ft thick

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkPresumptive Evidence of DNAPL

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):
  Other
Additional VI Information:
  Performed excavation of contaminated soil behind building and under building floor slab. Installed piping for soil vapor extraction system.

Remediation Scenario

Cleanup Goals:
  Soil: PCE = 30 ug/kg, TCE = 30 ug/kg

Groundwater: PCE = 3 ug/L, TCE = 3 ug/L, cis 1,2-DCE = 70 ug/L, trans 1,2-DCE = 100 ug/L, 1,1-DCE = 7 ug/L, vinyl chloride = 1 ug/L
Remedy Level:
  Interim Action

Technologies

In Situ Biostimulation
 

Why the technology was selected:
Biostimulation was utilized because conditions are favorable for reductive dechlorination in groundwater and the excavation was into the top of the water table, which facilitated the introduction of the carbon amendment.

Date implemented:
First excavation: November 2 - December 1, 2009. Second excavation: February 15 - April 15, 2010.

Final remediation design:
The first excavation was conducted under the facility floor slab where the drycleaning machine was formerly lcoated and in the parking lot immediately adjacent to the building. Depth of excavation was 3.5 to 4 ft BLS. The excavation was stablized with wooden shoring. Approximately 140 tons of soil was removed and shipped off site. Four hundred pounds of lime (powdered limestone and dolomite) was placed in the excavation for pH adjustment. Ninety-three (93) gallons of HRC-X mixed with 93 gallons of water was emplaced in the excavation under the former facility. Two-inch diameter horizontal vapor extraction PVC screens were installed three feet below grade in the area within the bay that formerly housed the drycleaning operation and outside the bay in the parking lot. Piping was routed outside the building. Additionally, a one-inch diameter injection well (screened 5-25 ft BLS) to be utilized for future injection of carbon amendments and two monitor wells (screened 3-13 and 16-26 ft BLS) were installed in the excavated area within the former drycleaning facility to serve as performance monitoring wells. The area was backfilled and restored. The second source removal area was located behind the facility. Approximately 496 tons of soil was excavated from this area to a depth of from 3.5 to 9 ft BLS. Sheet piling was used to stablize the deeper (9 ft BLS) portion of the excavation. Four hundred pounds of lime (powdered limestone and dolomite) was placed in the excavation for pH adjustment. Approximately 420 pounds of EOS 595 and 80 ounces of vitamin B12 was emplaced in this excavation. The area was then backfilled and restored.

Results to date:
Groundwater monitoring conducted on March 16, 2011. Little contamination remains in the upper surficial aquifer (Zone A - water table to 20 ft BLS). PCE (35 ug/l) was detected in only one well and the highest concentraitons of TCE and cis 1,2-DCE were 51 and 190 ug/l, respectively. Virtually no vinyl chloride has been detected in groundwater at the site. No PCE is present in groundwater samples collected from Zone B (20-35 ft BLS)monitor wells. The highest remaining contaminant concentrations are in Zone B (1,200 ug/l TCE & 460 ug/l cis 1,2-DCE). The highest contaminant concentrations detected in Zone C (35-50 ft BLS) monitor wells were 460 ug/l TCE and 380 ug/l cis 1,2-DCE. No contaminants were detected in Zone D monitor wells (screened > 50 ft BLS).

Next Steps:
When available, a soil vapor extraction remedial system will be moved to the site and hooked up to the in-place piping for further remediaiton of the unsaturated zone under the strip mall. Two days of Membrane Interface Probe logging was conducted in and near the contaminant source area to aid in developing a remedial action plan for biostimulation of contaminated groundwater at the site.

Cost to Design and Implement:
All technologies: Design: 41,700 Implementation: $383,000

In Situ Soil Vapor Extraction
 

Why the technology was selected:
Soil vapor extraction was selected to remove contaminants from the soil beneath the building floor slab that could not be excavated.

Next Steps:
When available, a soil vapor extraction remedial system will be moved to the site and hooked up to the in-place piping for further remediaiton of the unsaturated zone under the strip mall. Two days of Membrane Interface Probe logging was conducted in and near the contaminant source area to aid in developing a remedial action plan for biostimulation of contaminated groundwater at the site.

Ex Situ Soil Removal
 

Why the technology was selected:
Excavation was chosen because most of the contaminated soil was accessible (outside the back of the building), and because PCE was sorbed to the peat in the soil and if not removed, would continue to desorb into the groundwater.

Date implemented:
First excavation: November 2 - December 1, 2009. Second excavation: February 15 - April 15, 2010.

Final remediation design:
The first excavation was conducted under the facility floor slab where the drycleaning machine was formerly lcoated and in the parking lot immediately adjacent to the building. Depth of excavation was 3.5 to 4 ft BLS. The excavation was stablized with wooden shoring. Approximately 140 tons of soil was removed and shipped off site. Four hundred pounds of lime (powdered limestone and dolomite) was placed in the excavation for pH adjustment. Ninety-three (93) gallons of HRC-X mixed with 93 gallons of water was emplaced in the excavation under the former facility. Two-inch diameter horizontal vapor extraction PVC screens were installed three feet below grade in the area within the bay that formerly housed the drycleaning operation and outside the bay in the parking lot. Piping was routed outside the building. Additionally, a one-inch diameter injection well (screened 5-25 ft BLS) to be utilized for future injection of carbon amendments and two monitor wells (screened 3-13 and 16-26 ft BLS) were installed in the excavated area within the former drycleaning facility to serve as performance monitoring wells. The area was backfilled and restored. The second source removal area was located behind the facility. Approximately 496 tons of soil was excavated from this area to a depth of from 3.5 to 9 ft BLS. Sheet piling was used to stablize the deeper (9 ft BLS) portion of the excavation. Four hundred pounds of lime (powdered limestone and dolomite) was placed in the excavation for pH adjustment. Approximately 420 pounds of EOS 595 and 80 ounces of vitamin B12 was emplaced in this excavation. The area was then backfilled and restored.

Results to date:
Groundwater monitoring conducted on March 16, 2011. Little contamination remains in the upper surficial aquifer (Zone A - water table to 20 ft BLS). PCE (35 ug/l) was detected in only one well and the highest concentraitons of TCE and cis 1,2-DCE were 51 and 190 ug/l, respectively. Virtually no vinyl chloride has been detected in groundwater at the site. No PCE is present in groundwater samples collected from Zone B (20-35 ft BLS)monitor wells. The highest remaining contaminant concentrations are in Zone B (1,200 ug/l TCE & 460 ug/l cis 1,2-DCE). The highest contaminant concentrations detected in Zone C (35-50 ft BLS) monitor wells were 460 ug/l TCE and 380 ug/l cis 1,2-DCE. No contaminants were detected in Zone D monitor wells (screened > 50 ft BLS).

Next Steps:
When available, a soil vapor extraction remedial system will be moved to the site and hooked up to the in-place piping for further remediaiton of the unsaturated zone under the strip mall. Two days of Membrane Interface Probe logging was conducted in and near the contaminant source area to aid in developing a remedial action plan for biostimulation of contaminated groundwater at the site.

Cost to Design and Implement:
All technologies: Design: 41,700 Implementation: $383,000

Costs

Cost for Assessment:
  $244,000
Cost for Operation and Maintenance:
 
Total Costs for Cleanup:
 

Lessons Learned

If peat is present in the the contaminant source area and is accessible, it should be excavated. Remove as much of the peat as possible, including excavating well below the water table if feasible. If not removed, contaminats will continue to desorb from the peat and it will be difficult to achieve reductions in contaminant concentrations in groundwater.

MIP is a good tool for determining contaminant mass distribution in contaminant source areas. MIP data should be used to determine screen intervals for injection and performance monitoring wells.

Contacts

Chris Pellegrino, Project Manager
Bureau of Waste Cleanup (MS4520)
Florida Department of Environmental Protection
Tallahassee, Florida 32399-2400
Phone:(850) 245-8972
E-Mail: Chris.Pellegrino@DEP.state.fl.us


Site Specific References

Site Assessment Report: 2005
Remedial Action Plan: 2008
Construction Completion Report: 2010

Groundwater Monitoring Reports: 2006 - present