Drycleaner Site Profiles

Former Sun State Supply, Inc., Orlando, Florida

Description
Historical activity that resulted in contamination.

Sun State Supply was a drycleaning wholesale supplier that operated at this site from 1985 to 1992. The facility occupied a portion of a warehouse at the site. PCE was stored in a 4000 gallon AST which received bulk deliveries via tank truck. The solvent was then transferred to 5-gallon containers for delivery to drycleaners.

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 12,000 ppb
Tetrachloroethene (PCE) soil 250 ppb
Trichloroethene (TCE) groundwater 17 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:   44ft bgs
Plume Size:   Plume Length: 1,000ft
Plume Width: 300ft
Plume Thickness: 37ft
Average Depth to Groundwater:   7.36ft

Lithology and Subsurface Geology

surficial aquifer
  silty, fine to medium-grained sand
Depth: 0-44ft bgs
44ft thick
Conductivity: 11.1ft/day
Gradient: 0.003ft/ft
intermediate aquifer
  clay
Depth: 44-48ft bgs
4ft thick
 
  silty, fine to medium-grained sand with clay & phosphate nodules
Depth: 49-93ft bgs
44ft thick

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkDNAPL Present

Remediation Scenario

Cleanup Goals:
  Groundwater: PCE = 3 ug/l, TCE = 3 ug/L

Soil: PCE = 30 ug/Kg
Remedy Level:
  Full Scale Remedy

Technologies

Ex Situ Air Stripping
 

Date implemented:
Pump & Treat: April 17, 2001

Final remediation design:
Pump & Treat: One 6-inch diameter schedule 40 PVC recovery well (screened 20-40 ft BLS) was installed. A Grunfos 1/2 HP submersible pump was installed. Design pumping rate is 10 gpm. Anticipated drawdown is 8 feet. Water is pumped to a 500-gallon holding tank. A 1/2 HP Myers transfer pump routes the water to a low-profile air stripper with a 2 HP centrifugal blower. A 1/2 Hp Myers transfer pump routes the treated water to a 5 ft x 50 ft x 5 ft infiltration gallery. Since the recovery well is located downgradient of the former Sun State property approximately 450 feet of one-inch diameter Schedule 40 PVC pipeline was installed through a horizontally drilled borehole to transport produced water back to the treatment compound.

Results to date:
The pump & treat system was taken off line on January 27, 2005 prior to the injeciton of KMnO4. The system operated at an average pumping rate of approximately 8 to 9 gpm. Approximately 17,400,000 of groundwater were recovered and treated. An estimated 14.6 pounds of VOCs were recovered. System VOC influent concentrations had dropped a high of 220 ug/L to 9.6 ug/L. In September of 2003, two 2-inch diameter Schedule 40 PVC injection wells were installed (screened 35-45 ft BLS0 in the downgradient portion of the contaminant plume. Approximately 16,500 gallons of KMnO4 solution (1,700 pounds of KMnO4 mixed with makeup water pumped from one of the recovery well) were injected over a two-day period at a rate of from 5 to 10 gpm. A second chemical oxidation injection event was conducted from April 28-29, 2006. Approximately 31,000 gallons of potassium permanganate solution (3,359 pounds of KMnO4) were injected into six (6) injection wells (all screened 35-45 ft bls) at a rate of 19.5 gpm. A groundwater monitoring event conducted in February 2008 found the highest contaminant concentration to be 54 ug/l PCE. PCE was the only contaminant detected.

Next Steps:
A third chemical oxidation injection event has been proposed. However, current plans are to continue groundwater monitoring.

Cost to Design and Implement:
Pump & Treat: $ 288,400 Chemical Oxidation: $ 43,100

Ex Situ Chemical Oxidation
 

Why the technology was selected:
The contaminant plume was actively migrating both laterally and vertically at the site due to construction and operation of a stormwater retention pound on the property adjacent to the site. Pump & treat was selected to contain the contaminant plume. Chemical oxidation was implemented after nearly three years of operation of the pump & treat system to expedite groundwater remedation by destroying most of the remaining contaminant mass.

Date implemented:
1st KMnO4 Injection Event: January 28 - 29 2005 2nd KMnO4 Injection Event: /April 28- 29, 2006.

Final remediation design:
Chemical oxidation using potassium permanganate. First injection event utilized 16,500 gallons of KMnO4 solution (1,700 lbs. KMnO4), injected at 5-10 gpm into two injecition wells screened 35-45 ft BLS. Second KMnO4 injection event: 31,000 gallons of KMnO4 solution injected at 3.4 gpm into six (6) injeciton wells.

Results to date:
The pump & treat system was taken off line on January 27, 2005 prior to the injeciton of KMnO4. The system operated at an average pumping rate of approximately 8 to 9 gpm. Approximately 17,400,000 of groundwater were recovered and treated. An estimated 14.6 pounds of VOCs were recovered. System VOC influent concentrations had dropped a high of 220 ug/L to 9.6 ug/L. In September of 2003, two 2-inch diameter Schedule 40 PVC injection wells were installed (screened 35-45 ft BLS0 in the downgradient portion of the contaminant plume. Approximately 16,500 gallons of KMnO4 solution (1,700 pounds of KMnO4 mixed with makeup water pumped from one of the recovery well) were injected over a two-day period at a rate of from 5 to 10 gpm. A second chemical oxidation injection event was conducted from April 28-29, 2006. Approximately 31,000 gallons of potassium permanganate solution (3,359 pounds of KMnO4) were injected into six (6) injection wells (all screened 35-45 ft bls) at a rate of 19.5 gpm. A groundwater monitoring event conducted in February 2008 found the highest contaminant concentration to be 54 ug/l PCE. PCE was the only contaminant detected.

Next Steps:
A third chemical oxidation injection event has been proposed. However, current plans are to continue groundwater monitoring.

Cost to Design and Implement:
Pump & Treat: $ 288,400 Chemical Oxidation: $ 43,100

Ex Situ Pump and Treat
 

Why the technology was selected:
The contaminant plume was actively migrating both laterally and vertically at the site due to construction and operation of a stormwater retention pound on the property adjacent to the site. Pump & treat was selected to contain the contaminant plume. Chemical oxidation was implemented after nearly three years of operation of the pump & treat system to expedite groundwater remedation by destroying most of the remaining contaminant mass.

Date implemented:
Pump & Treat: April 17, 2001

Final remediation design:
Pump & Treat: One 6-inch diameter schedule 40 PVC recovery well (screened 20-40 ft BLS) was installed. A Grunfos 1/2 HP submersible pump was installed. Design pumping rate is 10 gpm. Anticipated drawdown is 8 feet. Water is pumped to a 500-gallon holding tank. A 1/2 HP Myers transfer pump routes the water to a low-profile air stripper with a 2 HP centrifugal blower. A 1/2 Hp Myers transfer pump routes the treated water to a 5 ft x 50 ft x 5 ft infiltration gallery. Since the recovery well is located downgradient of the former Sun State property approximately 450 feet of one-inch diameter Schedule 40 PVC pipeline was installed through a horizontally drilled borehole to transport produced water back to the treatment compound.

Results to date:
The pump & treat system was taken off line on January 27, 2005 prior to the injeciton of KMnO4. The system operated at an average pumping rate of approximately 8 to 9 gpm. Approximately 17,400,000 of groundwater were recovered and treated. An estimated 14.6 pounds of VOCs were recovered. System VOC influent concentrations had dropped a high of 220 ug/L to 9.6 ug/L. In September of 2003, two 2-inch diameter Schedule 40 PVC injection wells were installed (screened 35-45 ft BLS0 in the downgradient portion of the contaminant plume. Approximately 16,500 gallons of KMnO4 solution (1,700 pounds of KMnO4 mixed with makeup water pumped from one of the recovery well) were injected over a two-day period at a rate of from 5 to 10 gpm. A second chemical oxidation injection event was conducted from April 28-29, 2006. Approximately 31,000 gallons of potassium permanganate solution (3,359 pounds of KMnO4) were injected into six (6) injection wells (all screened 35-45 ft bls) at a rate of 19.5 gpm. A groundwater monitoring event conducted in February 2008 found the highest contaminant concentration to be 54 ug/l PCE. PCE was the only contaminant detected.

Next Steps:
A third chemical oxidation injection event has been proposed. However, current plans are to continue groundwater monitoring.

Cost to Design and Implement:
Pump & Treat: $ 288,400 Chemical Oxidation: $ 43,100

Costs

Cost for Assessment:
  $ 115,800
Cost for Operation and Maintenance:
  $ 171,400 (includes monitoring)
Total Costs for Cleanup:
 

Lessons Learned

1. Groundwater mounding associated with the stormwater impoundment on the adjacent property appears to have caused the contaminant plume to mobilize.

2. The membrane interface probe proved to be an effective tool for defining the distribution of the predominant poriton of the contaminant mass. This information was used to select screen intervals for the injection wells to insure that the potassium permanganate contacted the areas of the contaminant plume with the highest contaminant concentrations.

Contacts

Karen Milcic, Project Manager
Bureau of Waste Cleanup (MS4520)
Florida Department of Environmental Protection
Tallahassee, Florida 32399-2400
Phone: (850) 245-8931
Karen.Milicic@dep.state.fl.us

Mike Lodato, PG, consultant
GeoSyntec Consultants
14055 Riveredge Drive, Suite 300
Tampa, Florida 33637
Phone: (823) 558-9829
mlodato@GeoSyntec.com

Site Specific References

Contamination Assessment Report: October 1997

Contamination Assessment Report Addendum: February 2000

Remedial Action Plan (Pump & Treat)

Remedial Action Plan (Chemical Oxidation): September 2004

O&M Reports: 2001 - 2008