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Aerobic PCE Bioremediation

CL-Out Aerobic PCE Bioremediation Pilot Study Results

A CL-Out bioremediation pilot study confirmed that aerobic PCE cometabolism removed dry cleaning solvent contamination from ground water.  The pilot study was located at a former dry cleaners.  At the site, the PCE in ground water was 27 parts per billion (ppb).  Bioaugmentation introduced CL-Out microbes and dextrose as the metabolic substrate by injected into the ground water up gradient from the sentinal monitoring well.  After 30 days the PCE concentration decreased to 20 ppb.  After 6 months the PCE concentration decreased to 16 ppb.

As the PCE was decreasing, the site conditions stayed aerobic.  The dissolved oxygen level in ground water decreased from 1.07 to 0.71 mg/l.  Meanwhile,  the ORP decreased from 99 to 45 mv.  These aerobic aquifer conditions support the conclusion that the PCE removal was through aerobic bioremediation.

CL-Out cometabolism uses a dioxygenase enzyme that is produced constituatively as the metabolic substrate is consumed.  The dioxygenase enzyme destabilizes the carbon bond in the PCE to convert the molecule to an organic acid that leads to complete mineralization.

CL-Out is a consortium of naturally-occurring microbes.  The microbes have the benefits of metabolic diversity and environmental stability.  They are non-pathogenic and safe for human health and the environment. Click here to find out more about CL-Out bioremediation.

 

 

Aerobic Cometabolism of TCE and 1,4-Dioxane – Field Demonstration

In a pilot study to compare aerobic cometabolism with anaerobic reductive dechlorination  to remediation TCE and 1,4-dioxane at a former industrial facility in New Jersey, aerobic cometabolism reduced the concentrations of both compounds while anaerobic reductive dechlorination was unsuccessful.  For aerobic cometabolism, CL-Out microbes were injected into the aquifer to a depth of 60 to 90 feet below ground.  The pilot treatment area was 500 square feet.  Monitoring wells were placed upgradient, sidegradient and downgradient of the injection point.  Ground water samples were taken on a monthly basis for 9 months.

The results showed that complete TCE mineralization, without the production of daughter products, was measured within the first month.  CL-Out bioremediation removed 80% of the TCE at 40 feet downgradient in less than three months.  CL-Out bioremediation reduced the 1,4-dioxane concentration to below detection limits at 20 and 40 feet downgradient in the first month.

Click here to view a summary case study.

 

 

1,1,1-TCA Bioremediation at an Industrial Site in Dayton, Ohio

CL-Out bioremediation reduced the concentration of 1,1,1-TCA in ground water at a steel manufacturing facility in Dayton, Ohio. Following implementation of ozone treatment and high vacuum extraction for more than 2 years, the contaminant concentrations remained high.  Bioaugmentation followed up on these treatments and reduced the 1,1,1-TCA concentration very quickly.  Within 30 days of bioaugmentation, the source area contaminant concentration decreased by 80%.  After a second application, the concentration decreased from the pre-treatment concentration of 1,100 ug/L to 1.4 ug/L.  The bioaugmentation effect was observed as far as 250 feet downgradient where the concentrations decreased by more than 50%.  Click here for the full case study.

 

 

Aerobic Cometabolism of Chlorinated Solvents

CL-Out® aerobic cometabolism successfully remediated solvents in ground water at an operating industrial site in central New Jersey.  The manufacturing and plating facility had historical petroleum and solvent releases.

Chlorinated solvents found in the ground water in two plumes covered a combined area of about one half acre.  A mix of chlorinated solvents including 1,1,1-TCA, 1,1-DCE and PCE in low concentrations icontaminated the ground water.    The remediation goal was to reduce the mass of contamination in the ground water plume to prevent mitigate off-site risks.

After the CL-Out aerobic cometabolism, ground water concentrations in all monitoring wells decreased by more than 80%, which was sufficient to meet the remediation standards.  Click here to download a complete case study.

CL-Out Bioaugmentation Following ISCO to Remediate TCE

CL-Out bioremediation was used to remediate ground water at an active manufacturing plant in eastern Massachusetts after ISCO treatment of TCE in groundwater reached a limit.  CL-Out was selected because the aquifer was naturally aerobic.  CL-Out cometabolizes TCE and other chlorinated solvents under aerobic conditions by producing an oxygenase enzyme that breaks the carbon to carbon bond.  Under aerobic conditions daughter products such as DCE and vinyl chloride are not formed.  30 days after one application of CL-Out the TCE concentration was reduced by 97% and the site remediation goals were achieved. Click here to download the case study.