EHC® ISCR Reagent is composed of controlled-release carbon, zero valent iron (ZVI) particles and nutrients used for the in situ treatment of groundwater and saturated soil impacted by heavy metals and persistent organic compounds such as chlorinated solvents, pesticides and energetics.
EHC is composed of controlled-release carbon, zero valent iron (ZVI) particles and nutrients used for stimulating in situ chemical reduction (ISCR) of otherwise persistent organic compounds in groundwater. Following placement of EHC into the subsurface environment, a number of physical, chemical and microbiological processes combine to create very strong reducing conditions that stimulate rapid and complete dechlorination of organic solvents and other recalcitrant compounds (e.g., explosives and organochlorine pesticides).
In situ chemical reduction (ISCR) is the combination of abiotic chemical reduction, using zero valent iron(ZVI) and/or reduced minerals (magnetite, pyrite), coupled with anaerobic bioremediation for the effective treatment of chlorinated solvents, pesticides, and energetics. Physical, chemical, and biological processes combine to create an extremely reduced environment that stimulates chemical and microbiological dechlorination of otherwise persistent compounds.
As featured in Remediation Journal, EHC Reagent was injected via direct push across the source area. Site specific challenges included a low permeability clayey lithology and a large degree of CVOC mass sorbed at the smear zone due to large variations in the groundwater table.
EHC was injected into a series of permeable reactive barriers (PRBs) across the plume with the goal to treat the entire plume area over time. After only 6 months CT concentrations were reduced by 99.7%, with all monitoring wells meeting the groundwater clean up criteria.
The EHC® PRB was installed as a line of direct push injection points across the width of the plume. Twelve years after the installation the PRB is still supporting >90% reduction in inflowing CT concentrations and the downgradient plume has reduced significantly in size and concentration.
As featured in Remediation Journal, EHC® Reagent and KB-1® Bioaugmentation Culture were injected across the highest concentration area from approximately 40 to 112 ft bgs using direct push. Prior to treatment dissolved phase concentrations ranged as high as 592,000 and 90,000 μg/L for TCE and cis-DCE, respectively.
As featured in Remediation Journal, EHC Reagent was emplaced via hydraulic fracturing into fine-grained sandstone to remediate TCE in groundwater.
A colorless liquid that is mobile in groundwater, toxic at low levels, and has a high density, making cleanup activities more difficult than for oil spills.
A chlorinated hydrocarbon commonly used in dry cleaning and degreasing. Solubility in water 1.28 g / L and a log Kow of 320. May form dense non-aqueous phase liquids (DNAPLs). Anticipated to be a human carcinogen. MCL of 5 ppb.
A chloroalkane with two isomers (1,1,1- TCA and 1,1,2 – TCA) used widely as a solvent, especially in the electronics industry. It is considered insoluble in water and may for dense non-aqueous phase liquids (DNAPLs). Low toxicity but may impact central nervous system. MCL of 0.2 ppm.
A chlorinated hydrocarbon that is not easily soluble in water, but miscible with most organic solvents. A common source of the contaminant in drinking water is from the discharge from industrial chemical factories.
An organic compound formerly used in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent.
Commonly known by its old name ethyl chloride, it is a colorless, flammable gas or refrigerated liquid with a faintly sweet odor. Ethyl chloride is the least toxic of the chloroethanes. Exposure to ethyl chloride may occur from using consumer products containing it, including solvents, refrigerants, topical anesthetics, and in dyes, chemicals, and pharmaceuticals.
A colorless, sweet-smelling, dense liquid that is considered somewhat hazardous. Chloroform may be released to the air as a result of its formation in the chlorination of drinking water, wastewater and swimming pools. Other sources include pulp and paper mills, hazardous waste sites, and sanitary landfills.
Also called methyl chloride, R-40 or HCC 40, it is a chemical compound of the group of organic compounds called haloalkanes. Low levels of methyl chloride occur naturally in the environment, but higher levels may occur at chemical plants where it is or was made.
A group of three isomeric chemical compounds. They (ortho-chlorotoluene, meta-chlorotoluene, and para-chlorotoluene) consist of a disubsituted benzene ring with one chlorine atom and one methyl group.
Also called Dichloromethane (DCM), it is a colorless, volatile liquid with a moderately sweet aroma and is widely used as a solvent in paint strippers and removers; as a process solvent in the manufacturing of drugs, pharmaceuticals, and film coatings; as a metal cleaning and finishing solvent in electronics manufacturing; and as an agent in urethane foam blowing.
An organochloride used chiefly in the production of polyvinyl chloride (PVC) and may be a daughter product formed during the reductive dechlorination of TCE and DCE. Solubility in water 2.7 g / L and a Kow of 15. It is a known human carcinogen and causes liver damage. MCL of 2 ppb.
A colorless, flammable liquid with a sweet odor, it is used to make other organic chemicals, lead free gasoline, paper coating, soil fumigant for nematodes, and insecticide for stored grain.
A colorless liquid with a sweet smell that is a byproduct in the chlorination of propene to make allyl chloride. The general public may be exposed via inhalation near source areas or from the consumption of contaminated drinking water from wells near some hazardous waste sites.
A colorless liquid at room temperature that has an odor similar to that of turpentine. Also known as HCBD, it is primarily produced in chlorinolysis plants as a by-product in the production of carbon tetrachloride and tetrachloroethene.
1,1,1,2-Tetrachloroethane (R-130a) - A colorless liquid with a sweet chloroform-like odor that is used as a solvent and in the production of wood stains and varnishes. 1,1,2,2-Tetrachloroethane (R-130) – A chlorinated derivative of ethane. It has the highest solvent power of any chlorinated hydrocarbon.
Produced via the chlorination of propylene and as a byproduct of processes primarily used to produce.
also known as Bis(chloroethyl)ether. It is a clear liquid with the odor of a chlorinated solvent.
Pure pentachlorophenol exists as colorless crystals and impure pentachlorophenol is dark gray to brown and exists as dust, beads, or flakes. It is used as a pesticide, a disinfectant and as a wood preservative for utility poles, railroad ties, and wharf pilings.
Chlorobenzene will enter the atmosphere from fugitive emissions connected with its use as a solvent in pesticide formulations and as an industrial solvent. Releases into water and onto land will dissipate due to vaporization into the atmosphere and slow biodegradation in the soil or water.
1,2-Dichlorobenzene or ortho-dichlorobenzene - A colourless liquid that is poorly soluble in water but miscible with most organic solvents. 1,3-Dichlorobenzene or meta-dichlorobenzene. 1,4-Dichlorobenzene or para-dichlorobenzene - A colorless solid with a strong odor.
1,2,4-Trichlorobenzene - A colorless liquid used as a solvent for a variety of compounds and materials. 1,3,5-Trichlorobenzene - Colorless crystals, whereas the other isomers are liquids at room temperature.
A colorless, nearly odorless liquid that boils at about room temperature.
A very unreactive chlorofluorocarbon, that will stay in the atmosphere for a great deal of time if it is released.
A highly chlorinated organic pesticide that was used as an insecticide. Also known as chlordecone, it is a tan to white, crystalline, odorless solid.
Created when a substance called heptachlor is released to the environment and mixes with oxygen. It was used to kill termites found in the home and farmers used it to kill insects found on farm crops.
An organochlorine chemical variant of hexachlorocyclohexane that has been used both as an agricultural insecticide and as a pharmaceutical treatment for lice and scabies.
Commercial DDT is a mixture of several closely–related compounds. Dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) make up the balance. DDE and DDD are also the major metabolites and breakdown products in the environment.
A mixture of approximately 200 organic compounds, formed by the chlorination of camphene.
Can be formed from the synthesis of hexachloro-1,3-cyclopentadiene with norbornadiene in a Diels-Alder reaction, followed by epoxidation of the norbornene ring and is known to resist bacterial and chemical breakdown processes in the environment.
Manufactured from chloroacetic acid and 2,4-dichlorophenol, which is itself produced by chlorination of phenol.
is an organochloride that was primarily used as an insecticide and rodenticide and infamous as a persistent organic pollutant and banned in many countries.
Odorless, tasteless, clear to pale-yellow, viscous liquids (highly chlorinated mixtures are more viscous and deeper yellow), that are found in electric motors, transformers and capacitors.
Produced by a number of species of nitrifying bacteria and are mainly produced for use as fertilizers in agriculture because of their high solubility and biodegradability.
A yellow colored solid sometimes used as a reagent in chemical synthesis, found in military explosives or industrial applications.
A pale yellow crystalline solid that is well known as a precursor to TNT, and is usually used in the production of toluene diisocyanate, which is used to produce flexible polyurethane foams.
A heavy, colorless, oily, explosive liquid used in medicine, industry, and in explosives.
The salts derived from perchloric acid, that are often found near contaminated industrial sites.
