Global Efforts to Advance Remediation at Contaminated Sites
US and EU Perspectives on Green and Sustainable Remediation
Valence state: The combining capacity of an atom or radical determined by the number of electrons that it will lose, add, or share when it reacts with other atoms.
Source: The American Heritage™ Dictionary of the English Language, Fourth Edition
Copyright © 2000 by Houghton Mifflin Company.
free product: A NAPL found in the subsurface in sufficient quantity that it can be partially recovered by pumping or gravity drain.
aerobic: Direct aerobic metabolism involves microbial reactions that require oxygen to go forward. The bacteria uses a carbon substrate as the electron donor and oxygen as the electron acceptor. Degradation of contaminants that are susceptible to aerobic degradation but not anaerobic often ceases in the vicinity of the source zone because of oxygen depletion. This can sometimes be reversed by adding oxygen in the form of air (air sparging, bioventing), ozone, or slow oxygen release compound (e.g., ORC(r)).
Aerobic dechlorination may also occur via cometabolism where the dechlorination is incidental to the metabolic activities of the organisms. In this case, contaminants are degraded by microbial enzymes that are metabolizing other organic substrates. Cometabolic dechlorination does not appear to produce energy for the organism. At pilot- or full-scale treatment, cometabolic and direct dechlorination may be indistinguishable, and both processes may contribute to contaminant removal. For aerobic cometabolism to occur there must be sufficient oxygen and a suitable substrate which allows the microbe to produce the appropriate enzyme. These conditions may be present naturally but often in the presence of a source area oxygen and a substrate such as methane or propane will need to be introduced.
Adapted from US. EPA 2006 Engineering Issue: In Situ and Ex Situ Biodegradation Technologies for Remediation of Contaminated Sites
anaerobic: Direct anaerobic metabolism involves microbial reactions occurring in the absence of oxygen and encompasses many processes, including fermentation, methanogenesis, reductive dechlorination, sulfate-reducing activities, and denitrification. Depending on the contaminant of concern, a subset of these activities may be cultivated. In anaerobic metabolism, nitrate, sulfate, carbon dioxide, oxidized metals, or organic compounds may replace oxygen as the electron acceptor.
Anaerobic dechlorination also may occur via cometabolism where the dechlorination is incidental to the metabolic activities of the organisms. In this case, contaminants are degraded by microbial enzymes that are metabolizing other organic substrates. Cometabolic dechlorination does not appear to produce energy for the organism. At pilot- or full-scale treatment, cometabolic and direct dechlorination may be indistinguishable, and both processes may contribute to contaminant removal.
Quoted from US. EPA 2006 Engineering Issue: In Situ and Ex Situ Biodegradation Technologies for Remediation of Contaminated Sites
architecture: "Architecture" refers to the physical distribution of the contaminant in the subsurface. Residuals that take the form of long thin ganglia or small dispersed globules provide a larger surface area that will dissolve much faster than if the same amount of liquid were concentrated in a competent pool.
Sources: For purposes of this discussion, a DNAPL source zone includes the zone that encompasses the entire subsurface volume in which DNAPL is present either at residual saturation or as "pools" of accumulation above confining units. In addition, the DNAPL source zone includes regions that have come into contact with DNAPL that may be storing contaminant mass as a result of diffusion of DNAPL into the soil or rock matrix.
source zone: For purposes of this discussion, a DNAPL source zone includes the zone that encompasses the entire subsurface volume in which DNAPL is present either at residual saturation or as "pools" of accumulation above confining units. In addition, the DNAPL source zone includes regions that have come into contact with DNAPL that may be storing contaminant mass as a result of diffusion of DNAPL into the soil or rock matrix.
focal ulceration: The process or fact of a localized area being eroded away.
metaplasia of the glandular stomach: A change of cells to a form that does not normally occur in the tissue in which it is found.
hyperplasia of the glandular stomach: A condition in which there is an increase in the number of normal cells in a tissue or organ.
histiocytic: Degenerative.
duodenum: First part of the small intestine.
microcytic: Any abnormally small cell.
squamous cell papillomas: A small solid benign tumor with a clear-cut border that projects above the surrounding tissue.
squamous cell carcinomas: Cancer that begins in squamous cells-thin, flat cells that look under the microscope like fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of hollow organs of the body, and the passages of the respiratory and digestive tracts. Squamous cell carcinomas may arise in any of these tissues.
jejunum: The middle portion of the small intestine, between duodenum and ileum. It represents about 2/5 of the remaining portion of the small intestine below duodenum.
ileum: The distal and narrowest portion of the small intestine.
squamous: Flat cells that look like fish scales.
metaplasia: A condition in which there is a change of one adult cell type to another similar adult cell type.
ossification: The process of creating bone, that is of transforming cartilage (or fibrous tissue) into bone.
clastogenesis: Any process resulting in the breakage of chromosomes.
neoplastic: Abnormal and uncontrolled growth of cells.
ulceration: The process or fact of being eroded away.
leucocytosis: An elevation of the total number of white cells in blood.
neutrophils: A type of white blood cell.
chromodulin: A small protein that binds four trivalent chromium ions.
biomagnification: The increased accumulation and concentration of a contaminant at higher levels of the food chain; organisms higher on the food chain will have larger amounts of contaminants than those lower on the food chain, because the contaminants are not eliminated or broken down into other chemicals within the organisms.
exencephaly: Cerebral tissue herniation through a congenital or acquired defect in the skull.
everted viscera: Rotated body organs in the chest cavity.
To Be Considered: Documents, such as federal or state guidances, that are not legally binding but may be relevant to the topic in question.
gaining: A gaining surface water body is one where groundwater flows into it.
losing: A surface water body is losing when there is a permeable sediment bed that is not in contact with the groundwater allowing the surface water to seep through it.
fluvial: Of or pertaining to flow in rivers and streams.
lacustrine: Of or pertaining to a lake as in lacustrine sediments—sediments at the bottom of a lake.
lipid: Any class of fats that are insoluble in water.
lipophilic: Able to dissolve in lipids—in this case fatty tissue.
organelles: A part of a cell such as mitochondrion, vacuole, or chloroplast that plays a specific role in how the cell functions and membranes.
RfD: The RfD is an estimate of a daily exposure of the human population (including sensitive sub-groups) to a substance that is likely to be without "the appreciable risk of deleterious effects during a lifetime." An RfD is expressed in units of mg/kg-day.
autonomic: That part of the nervous system that controls non-conscious actions such as heart rate, perspiration and digestion.
ataxia: Lack of muscle coordination.
funnel-and-gate configuration: A system where low-permeability walls (the funnel) placed in the saturated zone direct contaminated ground-water toward a permeable treatment zone (the gate)
References: ATSDR (Agency for Toxic Substances and Disease Registry). 2015. Draft Toxicological Profile for Perfluoroalkyls. 574 pp.
EFSA (European Food Safety Authority). 2008. Opinion of the scientific panel on contaminants in the food chain on perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) and their salts. EFSA Journal 653:1-131.
Hekster, F.M., R.W.P.M. Laane, and P. de Voogt. 2003. Environmental and toxicity effects of perfluoroalkylated substances. Reviews of Environmental Contamination and Toxicology 179:99-121.
Higgins, C. and R. Luthy. 2006. Sorption of perfluorinated surfactants on sediments. Environmental Science & Technology 40(23):7251-7256.
HSDB (Hazardous Substances Data Bank). 2012 Update. Perfluorooctanoic acid.
Kaiser, M.A., B.S. Larsen, C-P.C. Kao, and R.C. Buck. 2005. Vapor pressures of perfluorooctanoic, -nonanoic, -decanoic, -undecanoic, and -dodecanoic acids. Journal of Chemical and Engineering Data 50(6):1841-1843.
Kauck, E.A. and A.R. Diesslin. 1951. Some properties of perfluorocarboxylic acids. Industrial and Engineering Chemical Research 43(10):2332-2334.
Lewis, R.J., Sr., ed. 2004. Sax's Dangerous Properties of Industrial Materials. 11th ed. Wiley-Interscience, Hoboken, NJ. V3:2860.
Lide, D.R. 2007. CRC Handbook of Chemistry and Physics. 88th ed. CRC Press, Boca Raton, FL. 3-412.
SRC (Syracuse Research Corporation). 2016. PHYSPROP Database. SRC Scientific Databases,
Accessed May 2016.
UNEP (United Nations Environmental Program). 2015. Proposal to List Pentadecafluorooctanoic Acid (CAS No: 335-67-1, PFOA, Perfluorooctanoic Acid), Its Salts and PFOA-Related Compounds in Annexes A, B and/or C to the Stockholm Convention on Persistent Organic Pollutants. UNEP/POPS/POPRC.11/5.
USEPA (U.S. Environmental Protection Agency). 2016. Drinking Water Health Advisory for Perfluorooctanoic Acid (PFOA).#pdfsmall# Office of Water, EPA 822-R-16-005, 103 pp
In recognizing that contaminated site cleanup creates an environmental footprint of its own, the United States (US) and other countries have developed policy and technical initiatives over recent years to optimize environmental performance and outcomes of cleanup projects through green remediation strategies. These initiatives involve increasing our understanding of the environmental footprint of site remediation and, when appropriate, taking steps to minimize that footprint. Worldwide consortia also recognize that a holistic approach to contaminated land management decisions offers a means to address the economic and social aspects of site cleanup, along with environmental outcomes, in a manner that is sustainable.
"US and EU Perspectives on Green and Sustainable Remediation" is an open-access Internet seminar series presented by the USEPA in cooperation with regulators and other stakeholders in the European Union (EU). The initial seminar was delivered in 2010 as a primer for the first "green and sustainable (GSR) remediation" panel session at a ConSoil international conference, with the intent of providing background information on rapidly evolving GSR initiatives and enabling attendees to make the most of limited time during ConSoil 2010.
Since ConSoil 2010, additional internet seminars have been offered to the public to provide updates on international initiatives, case studies on GSR implementation within the US and EU, and products under development throughout the world to support GSR. Many of the seminar topics mirror information exchanged in recent international conferences dedicated to the topic of GSR, such as:
- Sustainable Remediation 2012, which was held in Vienna, Austria, and jointly sponsored by the USEPA, EURODEMO+, and CL:AIRE
- Green Remediation: Environment ~ Energy~ Economics, which was held in the US at Amherst, Massachusetts, in 2010 and followed by Sustainable Remediation 2011: State of the Practice
- GreenRemediation 2009, which was held in Copenhagen, Denmark, and jointly sponsored by the Danish Ministry of the Environment and several industry partners.
Seminar Archives
Sustainable Remediation, April 15, 2014
This one-hour Internet seminar served as a pre-conference workshop for the Sustainable Remediation Conference 2014 and included four presentations:
- Green Remediation: An Overview of the State of the Practice; Carlos Pachon, USEPA
- Entities leading green & sustainable remediation: global update; Dietmar Muller-Grabherr, Environment Agency Austria
- Insight on themes for upcoming Sustainable Remediation Conference: Agenda and Host Country Goals; Marco Falconi, Italy/ISPRA, and Claudio Albano, SuRF Italy/CH2M Hill
- High resolution site characterisation coupled with in situ thermal as a means of sustainable remediation; Alan Thomas, NICOLE/ERM UK
- Using Quantitation to Develop Sustainable Solutions; Paul Favara, CH2M Hill US
View or download the archived seminar.
US and EU Perspectives on Green and Sustainable Remediation, Part 5, October 9, 2012
This two-hour Internet seminar addressed the Sustainable Remediation Conference 2012 in Vienna, Austria, and provided an overview of the following conference presentations.
- Conceptual Framework: considering sustainability within remedial approaches
- Sustainability Assessment: methodologies, models, and tools for sustainable remediation and
- Sustainability Management: case studies of sustainable remediation projects
An open forum was held throughout the seminar to respond to participant questions. View or download the archived seminar.
US and EU Perspectives on Green and Sustainable Remediation, Part 4, March 6, 2012
This two-hour Internet seminar provided participants with:
- A US case study on greening
Superfund cleanup at the Apache Powder Superfund Site in Arizona
- A case study on how GSR efforts are implemented in Central Europe
- Austria's new tool for performing a cost-effectiveness analysis that integrates the environmental and socio-economic dimensions of sustainability
- An update on developments that support USEPA's greener cleanup iniatiative (e.g., EPA's environmental footprint methodology for estimating or quantifying a remediation project's footprint) and the ASTM International effort to develop a voluntary consensus-based standard for greener cleanups
- Updates on international GSR efforts and
- Information on 2012 GSR internet seminars and conferences
An open forum was held throughout the seminar to respond to participant questions. View or download the archived seminar.
US and EU Perspectives on Green and Sustainable Remediation, Part 3, October 26, 2011
This two-hour Internet seminar provided participants with:
- An introduction to the USEPA's draft methodology for estimating or quantifying a remediation project's environmental footprint
- Case studies on GSR efforts applied in the US and EU
- Information presented during the GSR track at the October 2011 International Committee on Contaminated Land (ICCL) meeting, including key points from the Common Forum on Contaminated Land in the European Union (Common Forum) paper on sustainable and risk-informed land management; and
- Updates from initiatives around the world.
An open forum was held throughout the seminar during which participants' questions were addressed. View or download the archived seminar.
US and EU Perspectives on Green and Sustainable Remediation Part 2, March 15, 2011
The focus of this two-hour Internet seminar was to clarify the common elements and differences between green remediation and sustainable remediation and provide US and EU case studies of green remediation. Panelists included representatives from the USEPA, Environment Agency Austria (EAA), and Sustainable Remediation Forum (SuRF) - United Kingdom (UK). In addition, presenters from the July 2010 Internet seminar "US and EU Perspectives on Green and Sustainable Remediation" and a September 2010 ConSoil special session attended the seminar, representing SURF US and the Netherlands; EURODEMO+; Network for Industrially Contaminated Land in Europe (NICOLE); Common Forum on Contaminated Land in Europe; and Environment Canada. View or download the archived seminar.
US and EU Perspectives on Green and Sustainable Remediation, July 12, 2010
This interactive Internet seminar acted as a primer for the Special Session 8A Sustainable Remediation: International Initiatives which took place at ConSoil 2010. During the seminar, international leaders of GSR efforts discussed their drivers and constraints as well as the impacts of these opportunities and issues. An open forum after the presentations provided participants an opportunity to submit questions to the panel of speakers, which included representatives from the following organizations: USEPA; Environment Canada; SuRF US, SuRF UK, and SuRF Netherlands; EURODEMO+; NICOLE; and the Common Forum on Contaminated Land in Europe. View or download the archived seminar.
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