Drycleaner Site Profiles

Former Big B Cleaners, Warrington, Florida

Description
Historical activity that resulted in contamination.

Drycleaning was conducted at this facility from 1972 until 1978. The facility was located in a strip shopping mall in a mixed commercial/residential setting. A laundromat that ran a coin-operated perchloroethylene (PCE) drycleaning machine was located in the same strip mall. In 1977, a valve failed on an above-ground storage tank (AST) that contained perchloroethylene (PCE) at the Big B facility, releasing approximately 275 gal of PCE. In 1983, PCE was detected in a public water supply well located approximately 400 ft hydraulically downgradient of the facility. Wellhead treatment (granular activated carbon) has been installed at the water supply well. A consulting firm conducted a contamination assessment and installed a 3-well groundwater pump-and-treat system for the property owner that operated from 1993-1995 and treated approximately 8 million gal of water. The site became eligible for the Florida Drycleaning Solvent Cleanup Program in 1997.

Remediation Status: In groundwater monitoring


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


Contaminant Media Concentration (ppb) Nondetect
Tetrachloroethene (PCE) groundwater
Tetrachloroethene (PCE) soil

Site Hydrology

Deepest Significant Groundwater Contamination:   200ft bgs
Plume Size:   Plume Length: 2,650ft
Plume Width: 1,100ft
Average Depth to Groundwater:   8ft

Lithology and Subsurface Geology

Shallow Zone
  very fine to medium-grained sand
Depth: 0-77ft bgs
77ft thick
Conductivity: 32.3ft/day
Gradient: 0.0035ft/ft
Low Permeability Zone
  very fine to fine-grained sands interbedded with clays and sandy clays
Depth: 77-195ft bgs
118ft thick
Conductivity: 3.3ft/day
Gradient: 0.001ft/ft
Main Producing Zone
  fine to coarse sand with some clay lenses
Depth: 195-228ft bgs
33ft thick
Conductivity: 70ft/day
Gradient: 0.007ft/ft

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

Remediation Scenario

Cleanup Goals:
  Groundwater (MCL): PCE = 3 µg/L
Soils - Leachability-based levels (SCTLs): PCE = 30 µg/kg
Remedy Level:
  Full Scale Remedy

Technologies

In Situ Chemical Oxidation
 

Why the technology was selected:
Chemical oxidation was selected to address high contaminant concentration in groundwater in a deeper lower permeability zone between 90 and 115 feet BLS. Fenton's Reagent was chosen because of the proximity of the site to a public water supply well. Total organic carbon concentrations in the aquifer ranged from less than 500 mg/kg to 720 mg/kg (0.72%).

Date implemented:
First chemical oxidation injection event: June 18- July 24, 2004 2nd chemical oxidation injection event: July 18 - August 4, 2005

Final remediation design:
Two chemical oxidation injection events (Fenton's Reagent) were conducted at the site, the first from June 22-July 12, 2004 and the second one from July 18-August 4, 2005. Injection occurred in fifteen (15) injection wells constructed of 2-inch diameter Schedule 80 PVC. Eight (8) of the wells were screened 95-105 ft BLS. Five wells were screened 85-95 ft BLS. One well was screened 100-115 ft BLs and one well was screened 85-95 ft BLS. One day prior to chemical oxidant injeciton 100 gallons of a ferrous iron sulfate, sodum persulfate and hydrochloric acid solution conditioner was injected into each well to promote generation of hydroxyl radicals by Fenton's Reaction and to lower the pH. The chemical oxidant was a 11.7% hydrogen peroxide solution. Approximately 600 gallons of this solution was injected into each of 20 injeciton interval for a total injection volume of 12,000 gallons per each of the two injection event.

Results to date:
The chemical oxidation injections resulted in a reduction of PCE concentrations in groundwater samples collected from source area monitor wells. Based on groundwater monitoring, the highest pre-injection PCE concentration detected in groundwater was 1,500 ug/l. The highest PCE concentration detected in the contaminant source area in the first monitoring event conducted after the second chemical oxidaiton injection event was 357 ug/l PCE.

Next Steps:
The site is currently in groundwater monitoring. A monitoring event conducted in December 2008 found that the highest contaminiant concentration in a groundwater sample collected on the property where the drycleaning facility was formerly located and where remediation occurred was 42.1 ug/l PCE. Two off property wells had PCE concentrations of 531 ug/l and 758 ug/l. Groundwater produced from the nearby water supply well is still being treated via G.A.C.

Cost to Design and Implement:
Pilot Chem-Ox Design: 27,900 Pilot Chem-ox implementation & Full-scale Remedial Action Plan: $78,200 Implement Chem-ox (njection well installation & 2 injection events: $479,700

In Situ Multi Phase Extraction
 

Why the technology was selected:
Multiphase extraction was utilized to depress the water table and expose the shallow sediments for VOC extraction via the soil vapor extraction system.

Date implemented:
Multiphase Extraction/Soil Vapor Extraction: March 1, 2000.

Final remediation design:
The multiphase extraction system consisted of one 4-inch diameter PVC well screened 3-38 ft BLS. Design pumping rate was 10 gpm. Estimated radius of influence was 59 feet. Groundwater recovery is via a 1/2 HP Grunfos submersible pump. Extracted groundwater is treated in a low profile air stripper. The water is then treated via two liquid phase Carbtrol HP-200 carbon filters and discharged to an injection well.

Results to date:
The multiphase extraction/SVE systems operated for approximatley 8.25 months and were shut down on January 17, 2001. An estimated 214.6 pounds of VOCs were recovered in vapor phase. The multiphase system produced and treated an estiamted 889,795 gallons of groundwter recoverying an estimated 1.15 pounds of VOCs.

Next Steps:
The site is currently in groundwater monitoring. A monitoring event conducted in December 2008 found that the highest contaminiant concentration in a groundwater sample collected on the property where the drycleaning facility was formerly located and where remediation occurred was 42.1 ug/l PCE. Two off property wells had PCE concentrations of 531 ug/l and 758 ug/l. Groundwater produced from the nearby water supply well is still being treated via G.A.C.

Cost to Design and Implement:
SVE/MPE: $141,000

In Situ Soil Vapor Extraction
 

Why the technology was selected:
Multiphase extraction was utilized to depress the water table and expose the shallow sediments for VOC extraction via the soil vapor extraction system.

Date implemented:
Multiphase Extraction/Soil Vapor Extraction: March 1, 2000.

Final remediation design:
The SVE system consisted of two horizontal vapor recovery wells with 10 foot screen lengths installed one and one-half feet BLS. The system was powered by a 4 HP Ametek Rotron regenerative blower. Off gas was treated via two Carbtrol G-1S vapor-phase carbon canisters piped in series.

Results to date:
The multiphase extraction/SVE systems operated for approximately 8.25 months and were shut down on January 17, 2001. An estimated 214.6 pounds of VOCs were recovered in vapor phase. The multiphase system produced and treated an estiamted 889,795 gallons of groundwter recoverying an estimated 1.15 pounds of VOCs.

Next Steps:
The site is currently in groundwater monitoring. A monitoring event conducted in December 2008 found that the highest contaminiant concentration in a groundwater sample collected on the property where the drycleaning facility was formerly located and where remediation occurred was 42.1 ug/l PCE. Two off property wells had PCE concentrations of 531 ug/l and 758 ug/l. Groundwater produced from the nearby water supply well is still being treated via G.A.C.

Cost to Design and Implement:
SVE/MPE: $141,000

Ex Situ Air Stripping
 

Date implemented:
Multiphase Extraction/Soil Vapor Extraction: March 1, 2000.

Final remediation design:
The multiphase extraction system consisted of one 4-inch diameter PVC well screened 3-38 ft BLS. Design pumping rate was 10 gpm. Estimated radius of influence was 59 feet. Groundwater recovery is via a 1/2 HP Grunfos submersible pump. Extracted groundwater is treated in a low profile air stripper. The water is then treated via two liquid phase Carbtrol HP-200 carbon filters and discharged to an injection well.

Results to date:
The multiphase extraction/SVE systems operated for approximately 8.25 months and were shut down on January 17, 2001. An estimated 214.6 pounds of VOCs were recovered in vapor phase. The multiphase system produced and treated an estiamted 889,795 gallons of groundwter recoverying an estimated 1.15 pounds of VOCs.

Next Steps:
The site is currently in groundwater monitoring. A monitoring event conducted in December 2008 found that the highest contaminiant concentration in a groundwater sample collected on the property where the drycleaning facility was formerly located and where remediation occurred was 42.1 ug/l PCE. Two off property wells had PCE concentrations of 531 ug/l and 758 ug/l. Groundwater produced from the nearby water supply well is still being treated via G.A.C.

Cost to Design and Implement:
SVE/MPE: $141,000

Ex Situ Carbon Adsorption
 

Date implemented:
Multiphase Extraction/Soil Vapor Extraction: March 1, 2000.

Final remediation design:
The multiphase extraction system consisted of one 4-inch diameter PVC well screened 3-38 ft BLS. Design pumping rate was 10 gpm. Estimated radius of influence was 59 feet. Groundwater recovery is via a 1/2 HP Grunfos submersible pump. Extracted groundwater is treated in a low profile air stripper. The water is then treated via two liquid phase Carbtrol HP-200 carbon filters and discharged to an injection well.

Results to date:
The multiphase extraction/SVE systems operated for approximately 8.25 months and were shut down on January 17, 2001. An estimated 214.6 pounds of VOCs were recovered in vapor phase. The multiphase system produced and treated an estiamted 889,795 gallons of groundwter recoverying an estimated 1.15 pounds of VOCs.

Next Steps:
The site is currently in groundwater monitoring. A monitoring event conducted in December 2008 found that the highest contaminiant concentration in a groundwater sample collected on the property where the drycleaning facility was formerly located and where remediation occurred was 42.1 ug/l PCE. Two off property wells had PCE concentrations of 531 ug/l and 758 ug/l. Groundwater produced from the nearby water supply well is still being treated via G.A.C.

Cost to Design and Implement:
SVE/MPE: $141,000

Costs

Cost for Assessment:
  $47,389
Cost for Operation and Maintenance:
  Two semi-annual groundwater monitoring events: $18,000/year
Total Costs for Cleanup:
 

Lessons Learned

1. Although PCE had been the only contaminant detected in both soil and groundwater samples collected at the site, TCE and Cis 1,2-DCE was detected in source area groundwater samples following the two chemical oxidation injection events.

2. The Schedule 80 PVC casing/screen used for the injection wells proved to be servcicable for the chemical oxidant injections. No warping was noted.

3. Due to the number of monitoring wells and their depths (to over 200 feet), passive difusion bags are being utilized to reduce monitoring costs.

Contacts

Stacie Davis, Project Manager
FDEP, Division of Waste Management
Bureau of Waste Cleanup, Hazardous Waste Cleanup Section
2600 Blair Stone Road, MS 4520
Tallahassee, FL 32399-2400
850-245-8967
Anastasia.Davis@dep.state.fl.us

Brian Moore, PE, Contractor
HSA Environmental Engineers & Scientists
4019 East Fowler Ave.
Tampa, FL 33617
813-971-3882
Bmoore@hsa-env.com

Site Specific References

Interim Remedial Action Plan - March 1997

Remedial Alternatives Analysis - February 1999

Interim Remedial Action Plan - Feb. 1999

SVE Summary Closure Report - Feb. 2001

Pilot Study Plan - March 2002

Remedial Action Plan - Jan. 2004

Remedial Action Plan Implementation Report Phase I - October 2004

Remedial Action Plan Implementation Report Phase II - October 2005

Groundwater Monitoring Reports- 1998- present