Chlorinated solvents in groundwater can be treated with bioremediation techniques to clean chemicals left behind by manufacturing and dry cleaning facilities. Using food-grade vegetable oil products is proving to be an efficient and cost-effective method.
Manufacturing and dry cleaning facilities operating in the 1960s through the 1980s left behind a legacy of ground water contaminated with chlorinated solvents. The chemicals, such as trichloroethylene, tetrachloroethylene or dichloroethylene, are often found today in groundwater at concentrations above Environmental Protection Agency maximum contamination levels.
Remediation using a food-grade vegetable oil product known as CAP18® is proving to be an efficient and cost-effective method to reduce contaminant levels in groundwater. Once a contaminant plume is mapped, the liquid is injected into the ground in a grid pattern at distances and depths determined based on the soil type, plume size and contamination levels.
The CAP18 spreads into the saturated soil and becomes a concentrated hydrogen source, creating conditions that degrade the solvent. Because it is less soluble than other injection remediation products, it remains as a hydrogen source for months, limiting the need for reinjection. It is more viscous as well, preventing it from migrating too quickly through the soil.
Performance monitoring data for more than 10 Burns & McDonnell remediation projects using CAP18 indicate it creates an environment of enhanced natural attenuation of solvents in groundwater. Long-term monitoring time and costs can be significantly reduced while bringing contaminant levels below regulatory limits.