Fast Bioremediation Eases Site Development in Boston

Underground storage tank (UST) leaks from a former gas station contaminated shallow ground water under a parking lot for a commercial building.  The UST contamination was found during trenching for utilities.  As the presence of contamination prevented further property development, fast remediation was important to the stakeholders.

The size of ground water plume that resulted from leaching soil contaminants was estimated to be 5,000 square feet.    The contamination was mainly diesel-range petroleum constituents, with the highest concentrations in the aliphatic range, but there were also scattered detections of xylene, toluene, and ethylbenzene.

Petrox bioremediation was implemented in the ground water.  Three units of Petrox (165 gallons) were injected into the contaminated ground water through vertical injection wells located up gradient of the monitoring wells.

After a single inoculation of Petrox, the contaminant concentrations were reduced across the property.  The following table shows the overall reduction in both the volatile and semi-volatile range hydrocarbons.

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Patent Granted for Perchlorate Bioremediation

The US Patent Office has granted a patent for bioremediation of perchlorate in contaminated media to Michael Saul of CL Solutions and Andrew Irwin of Irwin Engineers of Natick, Massachusetts. This patent is based on the application of bioremediation to remediate perchlorate contaminated soil, sediments and ground water at a site in Massachusetts.  CL Solutions and Irwin Engineers collaborated on the the remediation of the site, where the perchlorate concentrations were reduced by orders of magnitude in one year of active treatment.  The project is a featured case study elsewhere on this site.

 

Fast, Easy Drainage Ditch Cleanup

Petrox bioremediation of surface spills and TPH accumulation in drainage ditches and maintenance areas is simple. Using a simple manual sprayer, the Petrox is applied to the soil surface. The Petrox microbes begin bioremediation immediately to enhance natural digestion of the petroleum, like probiotics for petroleum destruction.  Unlike detergents that wash the visible oil deeper in the soil, Petrox microbes destroy the all of the oil.

The following chart and table show the results of the application of Petrox to petroleum-contaminated soil in a drainage ditch. After about 60 days, the TPH concentration was reduced by 67% in one location and over 90% in three locations.  A second application to the 30 ft. north area reduced the concentration even more.

The problem was solved for a total Petrox cost of $600.

houston soil treatment chart houston soil treatment table

 

 

 

Bioremediation of Industrial Fill

Historical industrial sites often have deposits of fill material containing a wide range of organic contaminants.   Perched ground water  present in the base of the fill is usually impacted by the contaminants and may provide a mechanism for off-property migration of the contaminants.  The organic contaminants are wide spread throughout the fill without a well defined source area.  Cost-effective remediation is difficult with this combination of conditions.

Bioaugmentation with CL-Out or Petrox can remove the contaminants from the fill and perched water by destruction in place.  The organisms in CL-Out and Petrox can metabolize a wide-range of organic chemicals at concentrations from separate-phase layers to part per trillion levels.  Soil and ground water contaminants are addressed simultaneously though injection of the microbes without disturbing the  site operations.

The following table shows typical results from a single application of Petrox to contaminated soil and perched ground water on July 10, 2011.  The remediation progress was tracked by ground water monitoring because it was the easiest sampling method once wells were in place.Industrial Fill TreatmentThe results show that within 30 days the contaminant concentrations in perched water were reduced by 50%.  After 60 days there was slight rebound in come of the contaminants, showing that more soil treatment may be necessary if lower cleanup goals needed to be maintained.

 

 

Vermont Dry Cleaner Remediation Using CL-Out

Cl-Out bioremediation was used to remove PCE from ground water at a dry cleaners in Vermont.  CL-Out micorbes were selected for bioremediation of the site because they are compatible with the natural aerobic aquifer conditions.  One application of CL-Out bioaugmentation reduced the PCE concentration by 90% in less than 6 months without increasing the vinyl chloride concentrations.

The following table summarizes the process of aerobic cometabolism of PCE.  The pre-bioaugmentation sampling showed aerobic conditions and a low population of Pseudomonas microbes.  After bioaugmentation the Pseudomonas population was higher.  As the microbes consumed the dextrose substrate and produced the oxygenase enzymes necessary for PCE destruction, the ORP and PCE concentrations decreased.  Six months after the bioaugmentation, the microbial population returned to the pre-bioaugmentation conditions.

Aerobic CL-Out Cometabolism Tracking