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Thomas
Solvents Superfund Site, Battle Creek,
MI
Problem
USTs contaminating a city's water wells.
Solution
A dual vacuum extraction/sparging pilot test system.
- The first groundwater sparging system at a Superfund site.
- Sparging resulted in a 21-fold increase in extracted toluene
concentrations and a 300 percent increase in extracted PCE and
TCE concentrations.
- Nitrogen injected to prevent iron fouling.
- Full-scale remediation implemented three months after completion
of pilot test.
- Over 45,000 pounds of VOCs removed.
- The first catalytic oxidizer treatment of chlorinated hydrocarbons
at a CERCLA site.
- A clean closure pending under CERCLA.
Tools and Technologies Used
Tyson's Superfund Site,
King of Prussia, PA
Problem
A four-acre uncontrolled dump site with a ROD for excavation.
Semi- and non-volatile DNAPL zones.
Solution
A pilot test that overturned the original ROD to vacuum extraction
and was followed by one of the largest full-scale vacuum extraction
systems in the world. Testing of OxyVACSM treatment of DNAPL zones.
- A system comprising over 150 vertical and horizontal wells
for Vacuum Extraction, Dual Vacuum Extraction and high pressure
air injection.
- A 15,000 scfm on-site carbon regeneration facility.
- A 10,000 sq. ft. processing plant, two 700 Hp vacuum extraction
units and two 250 Hp vacuum extraction units.
- Over 200,000 pounds of contaminants have been removed from
the site soils.
- Bench testing of Oxy VacSM showed rapid, effective and complete
mineralization of hydrocarbons.
- Preliminary field testing showed positive results.
Tools and Technologies Used
Problem
Multiple contaminated fuel and solvent pits on a CERCLA site.
Solution
Bioremediation of semi-volatiles in the vadose zone. A large-scale
vacuum extraction demonstration project leading to vacuum extraction
as a presumptive remedy for the base.
- Multiple chlorinated and petroleum hydrocarbons being degraded.
- Hot air injection being used for increased biological activity.
- A network of 17 wells targeting three different lithologic
zones and using three separate piping manifold systems
- Five 40 Hp/500 scfm vacuum extraction units
- A 2,500 scfm catalytic oxidizer and an integrated acid gas
scrubber.
- A bioremediation phase for evaluation of the biodegradation
of contaminants.
Tools and Technologies Used
Problem
A release of unleaded gasoline in soils and groundwater that
threatened a municipal well field.
Solution
Vacuum extraction system that successfully remediated the site.
- Initial hydrocarbon extraction rates as high as 2,000 pounds
per day and a total of over 22,000 pounds of gasoline hydrocarbons
recovered.
- Vapor concentrations decreased from 95.9 to 99.7 percent in
just 128 operating days over a period of six months.
- One of the first vacuum extraction remediations in the state
of Florida.
- Pilot test and full-scale remediation conducted in cooperation
with the Florida Department of Environmental Regulation.
Tools and Technologies Used
Problem
Gasoline contamination in low permeability clayey soils.
Solution
Integrated high vacuum/dual vacuum extraction system.
- Pilot system successful. Full-scale system implemented under
Louisiana's Department of Environmental Quality UST Fund.
- Comprised of 33 DVE wells, 50 injection wells and two vacuum
extraction units.
- System capable of pulling up to 28" Hg vacuum.
- Over 20,000 pounds of VOCs removed in less than one year.
Tools and Technologies Used
Problem
RCRA facility with chlorinated VOCs in low permeability soils.
Solution
High Vac system.
- Designed, constructed and operated a system capable of 28"
Hg on 16 wells installed through facilities' concrete floor.
- The system reduced soil concentrations to 0.08 ppm.
- Removed 200 pounds of chlorinated hydrocarbons and completed
remediation within specified time frame of performance-based
contract.
Tools and Technologies Used
Problem
A low permeability property transfer site with strata saturated
with free product.
Solution
An integrated dual vacuum extraction/pneumatic soil fracturing
system.
- 80,000 pounds of super unleaded gasoline have been recovered
by the system.
- Site recommended for closure in less than 10 months.
- Hot air injection integrated into the system.
- Increased extraction rates by up to a factor of three over
that those without hot air injection.
Tools and Technologies Used
Problem
Methyl ethyl ketone and trichloroethane in soil and groundwater
under a manufacturing facility.
Solution
An integrated, multi-zone pneumatic soil fracturing/vacuum extraction/bioremediation
system.
- 35 well casings and 210 pneumatic soil fracturing points
- 4 separate piping manifold systems
- 1,000 scfm thermal oxidizer
- A rapid remediation program for a property sale.
Tools and Technologies Used
Problem
72,000 cubic yards of soil and groundwater contaminated with
petroleum hydrocarbons.
Solution
Dual vacuum extraction and OxyVACSM.
- Dual vacuum extraction system reduced soil hydrocarbon concentrations
from over 1,000 ppm to non-detect in less than two months of
operations.
- Groundwater benzene concentrations decreased from 650 ppb
to 23 ppb in one monitoring well after the injection of H2O2.
Further injections brought all but one well below MCLs (maximum
contaminant levels).
- "No further remediation" approval was given after
less than five months of operations.
Tools and Technologies Used
Problem
Methylene chloride, toluene and methanol contamination near an
overpass and beneath a highway.
Solution
A below-grade dual vacuum extraction system.
- Installed wells below grade, including a horizontal well beneath
the highway.
- The dual vacuum extraction system dewatered the saturated
overburden, allowing effective remediation of the contaminant
plume.
- Extracted vapor concentrations declined 99.97 percent in 270
days of operations.
Tools and Technologies Used
Problem
Property sale and litigation situation.
Solution
Dual vacuum extraction system that remediated the soil and groundwater
in less than one year.
- Reduced a 60,000-square-foot hydrocarbon plume with 3 feet
of floating product and TPH concentrations up to 1,400 ppm to
non-detectable levels in 196 days.
- Over 17,000 pounds of hydrocarbons were removed and the site
was closed by the Los Angeles Regional Water Quality Control
Board.
- Total remediation operations took only eight months.
Tools and Technologies Used
Problem
10,000 square feet of soil and groundwater contaminated with
gasoline, preventing site development.
Solution
In situ bioremediation system to treat saturated zone.
- Low cost, low-impace system added nutrients and oxygen to
recirculated groundwater.
- Reduced total effluent aromatic hydrocarbon levels from 4,300
ppb to 9 ppb in 18 months.
- Remediation allowed sale of adjoining property with a significantly
enhanced property value.
Tools and Technologies Used
Problem
Numerous VOCs and semi-VOCs from a fire training pit.
Solution
Phased-in bioventing system.
- Vacuum extraction utilized for extraction of volatiles.
- Volatile removal by vacuum extraction will allow ex situ treatment
of shallow soils with heavy metals.
- Bioventing for treatment of the semi-volatiles in deeper soils.
Tools and Technologies Used
Problem Gasoline hydrocarbons beneath a multi-million dollar
facility. Solution A dual vacuum extraction/groundwater
sparging system.
- Remediation completed without impact on commercial facility.
- Groundwater sparging reduced groundwater hydrocarbon concentrations
from 800 ppb to non-detect in 30 days.
- The system design remediated the site three months earlier
than the 12-month performance period requirement.
Tools and Technologies Used
Wood-treating Facility,
Great Lakes State
Problem
Dissolved hexavalent chromium contamination of soil and groundwater.
Solution
In situ geochemical fixation of chromium in vadose and saturated
zone soils.
- Prior pump-and-treat system ineffective.
- Field pilot test work showed in situ fixation of chromium
was effective in sand aquifer.
- Pilot testing lead to one of the first projects approved for
voluntary remediation program.
- Full-scale remediation includes vadose zone and saturated
zone programs.
Tools and Technologies Used
Problem
400 cubic yards of soil contaminated with spent cutting oils.
Solution
Ex situ bioremediation system.
- System reduced initial total hydrocarbon concentrations from
2,000 ppm to 30-40 ppm in 12 months.
- Project demonstrated that addition of nutrients or oxidation
agent is not necessary for bioremediation.
- Soil was subsequently used for construction purposes.
Tools and Technologies Used
Problem
Arsenic and phosphate in groundwater.
Solution
In situ geochemical formation of stable ferric arsenate.
- Prior pump-and-treat measures ineffective.
- In situ fixation utilizes natural geochemistry.
- Eliminates waste of groundwater resource.
- Demonstrated as a more effective water treatment process for
surface treatment.
Tools and Technologies Used
Problem
Cyanide and dissolved metals from a pipeline rupture in the groundwater.
Solution
In situ chemical oxidation and bioremediation reduced cyanide
to non-detect levels in 50 days. Metals were precipitated in-place.
- Completed restoration in 60 days.
- Groundwater restored to non-detectable levels of cyanide.
- Used naturally-occurring bacteria and common, non-toxic reagents.
Tools and Technologies Used
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