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Pesticide Bioremediation – Landfarming Application for DDD, DDE and Toxaphene

Petrox® bioremediation was used to remediate pesticide-contaminated soil at an industrial location in California.

Soil Remediation

The soil contamination consisted of pesticides including 4,4-DDD, 4’4-DDE and toxaphene.  Soil samples were sent to CL Solutions for bench-scale treatability studies.   The following table shows the  maximum detected concentrations and the treatment results.

Contaminant
Untreated Concentrations (ug/Kg)
Post-treatment concentrations (ug/Kg)
4,4-DDD
390
250
4,4-DDE
380
220
Toxaphene
8,500
440

After the bench-scale verification, full-scale bioremediation was implemented.  The contaminated soil was placed in two stockpiles and treated with Petrox. The following table shows the pre- and post-treatment results.

Contaminant Concentrations (ug/Kg)
Contaminant
Pile 1
Pile 2
Before
After
Before
After
4,4-DDD
310
170
14
nd ( <5)
4,4-DDE
810
300
8.7
nd  (<5)
Toxaphene
12,000
7,300
380
nd (<5)

Conclusions

The Petrox treatment successfully reduced the concentrations of pesticide contaminants in the soil stockpiles.  For additional information or assessment of applicability to your site contact CL Solutions.

Benzo(a)pyrene Bioremediation Using Custom Blend Microbes

Benzo(a)pyrene is a difficult remediation challenge. It is resistant to biological and chemical destruction and extraction from soil.  CL Solutions Custom Blend microbes, however, have successfully remediated benzo(a)pyrene and other PAHs in soil during ex situ land farming treatment.  By placing the contaminated  material in windrows, controlling the temperature and moisture, the addition of Custom Blend microbes has reduced the benzo(a)pyrene concentration by as much as 330 ug/kg/day.

The same approach works on high as well as low concentrations.  At a site in Oregon, the benzo(a)pyrene concentration was reduced from 140 ug/Kg to below detection limits in 7 days.  At a site in Ohio, the benzo(a)pyrene concentration was reduced from 28,000 ug/kg to 3.8 ug/Kg in 60 days.  At both sites, Custom Blend microbes effectively treated the full suite of PAHs along with the benzo(a)pyrene.

Soil Mixing to Improve Distribution of Microbial Solution

Bioaugmentation results can be accelerated and amplified by soil mixing to improve distribution and contact.  The equipment shown in this example was used to blend Petrox with contaminated soil to a depth of 10 feet.

Soil Mixing Equipment to Improve Microbial Solution Distribution

Soil Mixing Equipment to Improve Microbial Solution Distribution

Click here to view a short video of soil mixing.

Surface Spills to Deep Subsurface Success With Petrox Bioremediation

Petrox bioremediation is used to remove petroleum contamination from soil and water under many different conditions.  From surface spills to deep soil and ground water contamination, Petrox has successfully removed the contamination and environmental risk.  This summary of case studies demonstrates the applicability of Petrox bioremediation to the full range and life cycle of petroleum spills. Click here to view the document.