Technologies
Remediation
Our technology guides collect information about many types of remediation technologies used to clean up contaminated sites. Current initiatives related to site cleanup, websites maintained by EPA and other federal agencies and state organizations, and recent documents are also included on this page.
Technology Pages
Activated Carbon (AC)-Based Technology involves emplacement of AC-based amendments for in situ remediation of soil and groundwater. AC-based amendments remove contaminants through adsorption by AC and degradation by reactive amendments.
Air Sparging involves the injection of air or oxygen through a contaminated aquifer to remove volatile and semivolatile organic contaminants by volatilization. The injected air helps to flush the contaminants into the unsaturated zone for treatment.
Bioreactor Landfills rapidly transform, degrade and stabilize organic waste through the addition of liquid and air enhance microbial processes.
Bioremediation uses microorganisms to degrade organic contaminants in soil, groundwater, sludge and solids. The microorganisms break down contaminants by using them as an energy source or cometabolizing them with an energy source.
Combined Remedies may be necessary to clean up a contaminated site. Combined remedies take advantage of two or more technologies to enhance the performance of each and achieve a synergistic effect. Treatment trains are typically planned series of actions that address the problem.
Electrokinetics applies low-intensity direct current through the soil between ceramic electrodes that are divided into a cathode array and an anode array. This current mobilizes charged species, causing ions and water to move toward the electrodes, and removal of contaminants at the electrode may be accomplished by several methods.
Evapotranspiration Covers utilize natural processes to manage water precipitating on municipal landfills, hazardous and industrial waste landfills to contain waste.
Fracturing for Environmental Site Remediation technologies enhance or create openings in bedrock or soil with low effective porosity, such as clay, to help soil and groundwater cleanup methods work better.
Groundwater Circulating Wells create a three-dimensional groundwater circulation pattern that can provide subsurface remediation inside a well, in the aquifer or both. Groundwater is drawn into a well through one screened section and is pumped through the well to a second screened section where it is reintroduced to the aquifer.
Horizontal remediation wells (HRWs) are installed below ground parallel to the ground surface or at a shallow angle using horizontal directional drilling. HRWs offer an alternative to the installation of conventional vertical wells or trenching, particularly where access to soil and groundwater contamination is impeded by surface or near-surface obstructions.
In Situ Chemical Oxidation typically involves reduction/oxidation (redox) reactions that chemically convert hazardous compounds to nonhazardous or less toxic compounds that are more stable, less mobile or inert.
In Situ Chemical Reduction places a reductant or reductant-generating material in the subsurface to degrade toxic organic compounds to potentially nontoxic or less toxic compounds. It immobilizes metals by adsorption or precipitation and degrades non-metallic oxyanions.
In Situ Flushing floods a zone of contamination with an appropriate solution to remove the contaminant from the soil. Contaminants are mobilized by solubilization, formation of emulsions or a chemical reaction with the flushing solutions and brought to the surface for disposal, recirculation or on-site treatment and reinjection.
Multi-Phase Extraction uses a vacuum system, sometimes combined with a downhole pump, to remove various combinations of contaminated groundwater, separate-phase petroleum product and vapors from the subsurface. The system lowers the water table around the well, exposing more of the formation for vapor extraction.
Nanoscale Materials for Environmental Site Remediation have been developed and used to remediate contaminated soil and groundwater, such as sites contaminated by chlorinated solvents or oil spills. Nanoscale materials can be highly reactive in part because of the large surface area to volume ratio and the presence of a larger number of reactive sites.
Natural Attenuation relies on natural processes to clean up or attenuate pollution in soil and groundwater. Natural attenuation occurs at most polluted sites. However, the right conditions must exist underground to clean sites properly.
Remediation Optimization uses defined approaches to improve the effectiveness and efficiency of an environmental remedy. Optimization approaches include site-wide optimization reviews, statistical evaluation tools, consideration of emerging technologies, review of operating system costs and the identification of cost reduction methods without loss of protectiveness.
Permeable Reactive Barriers are subsurface emplacements of reactive materials through which a dissolved contaminant plume must move as it flows, typically under natural gradient. Treated water exits the other side of the permeable reactive barrier.
Phytotechnologies are broadly defined as the use of vegetation to address contaminants in soil, sediment, surface water and groundwater. Cleanup objectives for phytotechnologies can be contaminant removal and destruction, control and containment or both.
Soil Vapor Extraction applies a vacuum to unsaturated zone soil to induce the controlled flow of air and remove volatile and some semivolatile organic contaminants from the soil.
Soil Washing separates contaminants sorbed onto fine soil particles from bulk soil in a water-based system. Soils and wash water are mixed in a tank or other treatment unit and usually separated using gravity settling.
Solidification and Stabilization encapsulates waste within a solid material, coat the waste with low-permeability materials to restrict contaminant migration or both. Solidification can be accomplished by mechanical processes or by a chemical reaction between a waste and binding reagents, such as cement, kiln dust, or lime/fly ash.
Solvent Extraction uses an organic solvent to separate organic and metal contaminants from soil. The solvent is mixed with contaminated soil in an extraction unit and then passed through a separator, where the contaminants and extractant are separated from the soil.
Thermal Treatment (ex situ) generally involves the destruction or removal of contaminants through exposure to high temperature in treatment cells, combustion chambers or other means. Contaminated media is contained during the remediation process.
Thermal Treatment (in situ) includes many different methods and combinations of techniques to apply heat to polluted soil, groundwater or both. The heat can destroy or volatilize organic chemicals, and the gases can be extracted through collection wells for capture and cleanup in a treatment unit.
Technology Selection Tools
Federal Remediation Technologies Roundtable Decision Support Tools (DSTs) Matrix
DSTs are interactive software tools used by decision-makers to help answer questions, solve problems, and support or refute conclusions. They can be incorporated into a structured decision-making process for environment site clean-up. DSTs often support multiple functions, such as data acquisition, spatial data management, modeling, and cost estimating. The Federal Remediation Technologies Roundtable matrix is a table that provides general information about each DST, such as the types of files that may be imported to, or exported from, the DST, the characteristics of applicable sites (contaminants and media) and the functions it performs. All DSTs that were evaluated are free to the public.
The Remediation Technologies Screening Matrix
Navy: Remediation Technologies
U.S. Environmental Solutions Toolkit: Buyer's Guide to U.S. Environmental Technologies and Service Providers
Brownfields Road Map to Understanding Options for Site Investigation and Cleanup
General Technology Resources
Superfund Cleanup Technologies
EPA prepares the Superfund Remedy Report to provide information and analyses on remedies EPA selected to address contamination at Superfund National Priorities List and Superfund Alternative Approach sites. This report is the latest in a series, prepared since 1991, on Superfund remedy selection. The latest edition focuses on the analysis of Superfund remedial actions selected in fiscal years 2018, 2019, and 2020.
The data that forms the basis of the analyses contained in SRR 17th Edition can be found at Superfund Data and Reports by downloading Contaminant of Concern Data for Decision Documents by Media and Remedy Component Data for Decision Documents by Media.
SERDP/ESTCP: ENVIRO Wiki
Green Remediation
For more information, please contact Luci Dunnington, Technology Integration and Information Branch, 202-566-0925, dunnington.lucila@epa.gov.
Superfund Analytical Services/Contract Laboratory Program (CLP) Tools
Fact Sheets for Communities
Community Guides to Cleanup Technologies
- Air Stripping
- Amended Sediment Caps
- Biochemical Reactors
- Bioremediation
- Capping
- Ecological Revitalization
- Evapotranspiration Covers
- Excavation of Contaminated Waste
- Fracturing for Site Cleanup
- Granular Activated Carbon Treatment
- Greener Cleanups
- In Situ Carbon Amendments
- In Situ Chemical Oxidation
- In Situ Chemical Reduction
- In Situ Sediment Amendment
- In Situ Thermal Treatment
- Incineration
- Monitored Natural Attenuation
- Permeable Reactive Barriers
- Phytotechnologies
- Pump and Treat
- Soil Vapor Extraction and Air Sparging
- Solidification and Stabilization
- Thermal Desorption
- Vapor Intrusion Mitigation
- Vertical Engineered Barriers
Email Newsletters
Newsletters on Innovative Treatment Technologies
The Technology Innovation News Survey contains market/commercialization information; reports on demonstrations, feasibility studies and research; and other news relevant to the hazardous waste community interested in technology development. This report is updated each month.
Federal Business Opportunities (FedBizOpps) contains summaries of procurement and contract award notices issued the previous week that pertain to hazardous waste, solid waste, underground storage tank remediation, and other environmental topics. However, it does not necessarily contain EVERY notice on these topics. Federal Business Opportunities (FedBizOpps) is published weekly.