Drycleaner Site Profiles

Hanner's Cleaners, Pompano Beach, Florida

Description
Historical activity that resulted in contamination.

This is an inactive drycleaning facility that used Stoddard solvent and PCE and operated from the early 1960's to 1989. No. 2 fuel oil (boiler fuel) contamination from leaking USTs is also present. The former facility has been razed. The contaminant source areas are the former location of a distillation unit, the soils under the facility floor slab and the former UST locations. One of the USTs was apparently formerly used to store petroleum solvent and may later have been used as a PCE waste disposal area. Identified contaminant source areas are: former UST areas, ditillation unit, lint trap and former location of drycleaning machine. The nearest water supply wells are located 1,500 to 2,000 feet northeast of the site.

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
cis-1,2-Dichloroethene groundwater
cis-1,2-Dichloroethene soil
1,1-Dichloroethene groundwater
ethylbenzene groundwater
Tetrachloroethene (PCE) groundwater
Tetrachloroethene (PCE) soil
Trichloroethene (TCE) groundwater
Trichloroethene (TCE) soil
toluene groundwater
trans-1,2-Dichloroethene groundwater
Vinyl Chloride groundwater

Site Hydrology

Deepest Significant Groundwater Contamination:   75ft bgs
Plume Size:   Plume Length: 1,350ft
Plume Width: 1,000ft
Plume Thickness: 70ft
Average Depth to Groundwater:   6.07ft

Lithology and Subsurface Geology

 
  Fine to medium-grained quartz sand with limestone stringers
Depth: 0-46ft bgs
46ft thick
Conductivity: 92ft/day
Gradient: 0.0007ft/ft
 
  Fine to medium-grained sand
Depth: 46-62ft bgs
16ft thick
 
  Coquina
Depth: 62-68ft bgs
6ft thick
 
  Fine-grained sand & sandstone with limestone stringers
Depth: 68-84ft bgs
16ft thick

Pathways and DNAPL Presence

checkGroundwater
checkSediments
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
Other
Additional VI Information:
  In addition to operation of a soil vapor extraction system, three excavations were conducted to remove contaminated soil at the site.

Remediation Scenario

Cleanup Goals:
  Groundwater - MCLs: PCE = 3 ug/l, TCE = 3 ug/l, cis-1,2-DCE = 70 ug/l, trans-1,2-DCE = 100 ug/l, vinyl chloride = 1 ig/l. Soils - leachability levels - PCE = 30 ug/kg, TCE = 30 ug/kg, cis-1,2-DCE = 400 ug/kg, TPH=340 mg/kg
Remedy Level:
  Full Scale Remedy

Technologies

In Situ Bioremediation
 

Why the technology was selected:
Biostimulation was chosen to polish low contaminant concentrations (primarily vinyl chloride) in groundwater. The aquifer is strongly anaerobic and reductive dechlorination is an active process in groundwater at the site.

Date implemented:
Bioremediation pilot test: July 14-15, 2004. Seven ethyl lactate injection events: February 2006 - October 2007.

Final remediation design:
Eight biostimulation injection events were conducted between July 2004 and October 2007. A total of 330 gallons of ethyl lactate was injected into 8 injection wells screened 6-30 and 6-40 ft BLS. The ethyl lactate was mixed with water to create a solution that was approximately 4% ethyl lactate by volume.

Other technologies used:
Biostimulation

Results to date:
In the latest groundwater monitoring event, conducted in January 2010, vinyl chloride was the only contaminant detected in groundwater in concentrations exceeding an MCL. Four monitor wells produced groundwater samples with detectable concentrations of vinyl chloride. Two of these wells had concentrations of 100 and 300 ug/l, compared to non-detect for the previous sampling event.

Next Steps:
Groundwater monitoring.

Cost to Design and Implement:
(for all technologies:) Design: $112,000 Implementation: $1,251,000

In Situ Chemical Oxidation
 

Why the technology was selected:
Chemical oxidation was chosen because contaminant concentrations indicated DNAPL was present in groundwater. In-situ remediation was determined more cost effective than removing, treating and re-injecting treated groundwater. Addtionally, matrix oxidant demand was low.

Date implemented:
First Excavation: May 10, 2000. A total of 166.7 cubic yards of soil was removed from Stoddard UST/distillation unit area. Chemical Oxidation Pilot Test: June 19-26, 2000. 2nd Chemical Oxidation Pilot Test: August 7 - 14, 2000. 1st full scale chemical

Final remediation design:
The chemical oxidation (Fenton's Reagent) pilot test consisted of two injection events. In the first injection event, a total of 2,600 gallons of catalyst and 5,200 gallons of 12% hydrogen peroxide solution was injected in to six four-inch diameter Schedule 40 PVC injection wells were installed. These wells screened 6-30 ft BLS with 0.20-inch slot screen. Bentonite seals were installed in the annulus at depths of 12-14, and 20-22 ft BLS. Injection was through a one and one-quarter inch diameter PVC pipe with K-packers straddling a screen interval in piping. The injection piping was lowered to the bottom screened interval and the K-packers bracketed the first inejction inteval 22-30 ft BLS. The K-packers and bentonite seals limited vertical migration of the injectant. The injection piping was then raised and injection occurred in the 14-20 ft interval and finally the 6-12 ft interval. The second injection of the pilot study occurred from August 7-14, 2000 and utilized the same injeciton wells and injection method. A total of 3,000 gallons of catalyst and 7,700 gallons of 12% hydrogen peroxide solution was injected. There were 3 full-scale chemical oxidation events. All utilized Fenton's reagent. The first one used 41,580 gallons of reagnet (incuded 12% hydrogen peroxide, injected into 31 injeciton wells (screened 6-30 ft BLS, 18-20 ft BLS, & 30-40 ft BLS. and 30 direct push borings, spaced 15 feet on denter, injection interval 12-18 feet. The second injection event also utilized 31 injeciton wells and 30 dierect push borings, with similar injeciton intervals and 45,870 gallons of reagent (including 12% hydrogen peroxide). The third full scale chemical oxidation event used 25,080 gallons of reagent (12% hydrogen peroxide). Injection was into 12 injection wells and 70 direct push borings.

Results to date:
In the latest groundwater monitoring event, conducted in January 2010, vinyl chloride was the only contaminant detected in groundwater in concentrations exceeding an MCL. Four monitor wells produced groundwater samples with detectable concentrations of vinyl chloride. Two of these wells had concentrations of 100 and 300 ug/l, compared to non-detect for the previous sampling event.

Next Steps:
Groundwater monitoring.

Cost to Design and Implement:
(for all technologies:) Design: $112,000 Implementation: $1,251,000

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, unsaturated sediments.

Date implemented:
Soil vapor extraction system startup: April 17, 2001.

Final remediation design:
The soil vapor extraction system consisted of two horizontal extraction wells with screen lengths of 30 and 10 feet. Each lateral was installed at a depth of approximately 2 feet six inches below grade. One well was installed due east of the facility in the vicinity of the former location of the distillation unit and the Stoddard solvent UST. The other lateral was installed north of the facility near the former location of the fuel oil USTs. The SVE system is powered by a 20 HP Rotron blower. Off gas is treated via four (4) 140-lb. G.A.C. vessels. Design flowrate is 635 scfm @ 40 inches of w.c.

Results to date:
The SVE sytem was shut down on May 3, 2002. In the latest groundwater monitoring event, conducted in January 2010, vinyl chloride was the only contaminant detected in groundwater in concentrations exceeding an MCL. Four monitor wells produced groundwater samples with detectable concentrations of vinyl chloride. Two of these wells had concentrations of 100 and 300 ug/l, compared to non-detect for the previous sampling event.

Next Steps:
Groundwater monitoring.

Cost to Design and Implement:
(for all technologies:) Design: $112,000 Implementation: $1,251,000

Ex Situ Carbon Adsorption
 

Date implemented:
Soil vapor extraction system startup: April 17, 2001.

Final remediation design:
The soil vapor extraction system consisted of two horizontal extraction wells with screen lengths of 30 and 10 feet. Each lateral was installed at a depth of approximately 2 feet six inches below grade. One well was installed due east of the facility in the vicinity of the former location of the distillation unit and the Stoddard solvent UST. The other lateral was installed north of the facility near the former location of the fuel oil USTs. The SVE system is powered by a 20 HP Rotron blower. Off gas is treated via four (4) 140-lb. G.A.C. vessels. Design flowrate is 635 scfm @ 40 inches of w.c.

Results to date:
The SVE sytem was shut down on May 3, 2002. In the latest groundwater monitoring event, conducted in January 2010, vinyl chloride was the only contaminant detected in groundwater in concentrations exceeding an MCL. Four monitor wells produced groundwater samples with detectable concentrations of vinyl chloride. Two of these wells had concentrations of 100 and 300 ug/l, compared to non-detect for the previous sampling event.

Next Steps:
Groundwater monitoring.

Cost to Design and Implement:
(for all technologies:) Design: $112,000 Implementation: $1,251,000

Ex Situ Soil Removal
 

Why the technology was selected:
Excavation/removal was selected because contaminated soil was accessible (building that formerly housed the drycleaning operation was razed).

Date implemented:
First Excavation: May 10, 2000. A total of 166.7 cubic yards of soil was removed from Stoddard UST/distillation unit area. Second excavation: June 2-7, 2004. Approximately 127.8 tons of contaminated soil excavated from former Stoddard Solvent UST/disti

Results to date:
In the latest groundwater monitoring event, conducted in January 2010, vinyl chloride was the only contaminant detected in groundwater in concentrations exceeding an MCL. Four monitor wells produced groundwater samples with detectable concentrations of vinyl chloride. Two of these wells had concentrations of 100 and 300 ug/l, compared to non-detect for the previous sampling event.

Next Steps:
Groundwater monitoring.

Cost to Design and Implement:
(for all technologies:) Design: $112,000 Implementation: $1,251,000

Costs

Cost for Assessment:
  $203,800
Cost for Operation and Maintenance:
  O&M (includes monitoring): $383,900 to date
Total Costs for Cleanup:
  $1,950,700 to date

Lessons Learned

1. Thorough assessment and delineation of the contaminant source area and definition of site stratigraphy to identify features that control contaminant distribution and oxidant movement is critical to successful remediation.

2. Segmented injection wells (alternating sand and bentonite at specific intervals) were employed along with a K-packer-equipped injector assembly to apply injections at distinct depth intervals within individual wells. This approach allowed cost savings on injection well installation, and appeared to facilitate the targeting of injections at specific depth intervals.

3. Biopolishing is not a recommended remedial strategy where there are only low concentrations of contaminants over a wide area.

Contacts

Sharonda Perkins, Contract Manager
Florida Department of Environmental Protection
(850-245-8970)
Sharonda.A.Perkins@dep.state.fl.us

Contractor:
Guy Frearson, Program Manager OR
AECOM
(954-745-7211)
Guy.Frearson@Aecom.com

Site Specific References

Contamination Assessment Report:1997
SVE Remedial Action Plan: October 2000.
Chemical Oxidation Remedial Action Plan: April 2001.
SVE startup Report: June 2001.
Remedial Action Plan Biostimulation: December 2005.
Operation & maintenance reports: 2000 - 2007
Groundwater monitoring reports: 1997 - present.

Fenton-based Remediation of a Chlorinated Solvent Groundwater Plume Using Segmented Injection Wells - a Field Study- Heijn, Kakarla, Hartsfield, Koenig-June 6/01