Lexikon

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abstraction limit value
accelerated solvent extraction

in other name accelerated solvent extraction, abbreviated as ASE, a sample preparation technique in determination of POP (Persistent Orcanic Pollutants) that combines elevated temperature and pressure with solvents to achieve fast and efficient removal of components of interest from any solid sample (soil, sediment, food, textile, waste, biological sample, ash, etc.). The solubility of compounds is enhanced at elevated temperature, e.g. rising the temperature from 50 °C to 150 °C the solubility of anthracene is increased 13 fold resulting in enhanced diffusion as well. The high pressure makes it possible to work on temperatures above the boiling point of the solvent and helps to the solvent to enter into the pores of the sample. ASE has been demonstrated to be equivalent to existing extraction methodologies, such as Soxhlet extraction. (Source: MOKKA database, sheet No. 582)

accuracy

accuracy is how close a numerical measure is to its actual value.

accuracy of measuring and testing
anthracene
Best Practicable Environmental Option
Best Practicable Environmental Option BPEO

the Best Practicable Environmental Option BPEO Twelfth Report, FEB 1988, Cm 310, is a set of procedures adopted by Great Britain with the goal of managing waste and other environmental concerns. According to the Royal Commission on Environmental Pollution, BPEO "emphasises the protection and conservation of the environment across land, air and water. The BPEO procedure establishes for a given set of objectives, the option that provides the most benefits or the least damage to the environment, as a whole, at acceptable cost, in the long term as well as in the short term."
Source: Wikipedia, http://en.wikipedia.org/wiki/Best_practicable_environmental_option

best practice
CARACAL, REACH

CARACAL is an expert group giving advice for the European Commission and ECHA (European Chemicals Agency) on questions related to REACH and CLP. It was founded as "European Commission Working Group on the Practical Preparations for REACH" in May 2004. As of September 2007, it was re-named into "REACH Competent Authorities (REACH CA)" and, as of March 2009, into "Competent Authorities for REACH and CLP (CARACAL)".

See also: http://ec.europa.eu/enterprise/sectors/chemicals/reach/caracal/index_en.htm

CARACAS Project
carbon tetrachloride

arbon tetrachloride is produced by the high temperature chlorination of propylene or methane. It is used as a feedstock in the production of CFCs, HCFCs and HFCs, as a process agent in the production of chlorine, to extract nitrogen trichloride, and as a solvent to recover chlorine from tail gas. It has been phased out in dispersive uses since 1995 under the Montreal Protocol.

characterisation in LCA
Chemical Abstract Service (CAS)

Chemical Abstracts Service maintains the most comprehensive list of chemical substances. Each substance registered in the CAS Registry is assigned a CAS Registry Number. The CAS Registry Number (commonly referred to as CAS number) is widely used as a unique identifier of chemical substances. (Source: REACH Glossary)

cracker, IT
cracker, IT2
direct abstraction from surface water
extract
in solvent extraction, the portion of a sample preferentially dissolved by the solvent and recovered by physically separating the solvent.
extractable organic halides
see EOX
extraction

method to separate components based on their relative solubilities (partition) in two different, immiscible solvents. In extraction" target="_blank">liquid/liquid extraction the solvent (usually organic) dissolves only the desired compounds from the sample solution (usually aqueous solution). In supercritical extraction the solvent is supercritical carbon dioxide. Soxhlet extraction is the tradional way for extracting solid samples, when the sample is connected with freshly boiled solvent in a special apparatus several times. The extraction of soild samples can be intensified by ultrasound (sonication assisted extraction, SAE) or elevated pressure and temperature (pressurized fluid extraction or accelerated fluid extraction, ASE). The solid phase extraction (SPE) is characterized by decreased sample and solvent need. Further miniaturization resulted in solid phase microextraction (SPME), stirbar+extraction and the membrane assisted extraction (MASE) techniques used for sample preparation for chromatography.

extraction from soil by organic solvents

solvent extraction uses an organic solvent as an extractant to separate organic and metal contaminants from soil. The organic solvent is mixed with contaminated soil in an extraction unit. The extracted solution then is passed through a separator, where the contaminants and extractant are separated from the soil. Organically bound metals may be extracted along with the target organic contaminants.

extraction from soil by solvents

solvent extraction from soil uses an organic solvent as an extractant to separate organic and metal contaminants from soil. The organic solvent is mixed with contaminated soil in an extraction unit. The extracted solution then is passed through a separator, where the contaminants and extractant are separated from the soil. Organically bound metals may be extracted along with the target organic contaminants.

extraction of LDNAPL from soil
fracture zones and hot spots

fracture zones and hot spots can be found in the litosphere, the rigid outer layer of Earth, beneath of oceans and continents.

Ain the Earth, the lithosphere includes the crust and the uppermost mantle, which constitute the hard and rigid outer layer of the Earth. The lithosphere is underlain by the asthenosphere, the weaker, hotter, and deeper part of the upper mantle. The boundary between the lithosphere and the underlying asthenosphere is defined by a difference in response to stress: the lithosphere remains rigid for very long periods of geologic time in which it deforms elastically and through brittle failure, while the asthenosphere deforms viscously and accommodates strain through plastic deformation. There are two types of lithosphere: 1) oceanic lithosphere, which is associated with oceanic crust and exists in the ocean basins, 2) continental lithosphere, which is associated with continental crust. The composition of the two types of crust differs markedly, with basaltic rocks ("mafic") dominating oceanic crust, while continental crust consists principally of lower density granitic rocks ("felsic"). The lithosphere is broken into tectonic plates. The following tectonic plates currently exist on the earth's surface with roughly definable boundaries. There are seven primary plates (African Plate, Antarctic Plate, Eurasian Plate, Indo-Australian Plate, North American Plate, Pacific Plate, South American Plate) and some secondary smaller plates (Arabian-, Caribbean-, Cocos-, Scotia-, Adria-, Aegean-, Arab-, Iranian-, Nazca-, Philippine Sea -plates).These plates are rigid segments that move in relation to one another at one of three types of plate boundaries: 1) convergent boundaries, at which two plates come together, (an example of such a boundary is the San Andreas fault in California) 2) divergent boundaries, at which two plates are pulled apart (the Atlantic Ocean was created by this process, the mid-Atlantic Ridge is an area where new sea floor is being created), and 3) transform boundaries, in which two plates slide past one another laterally. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation can occur along these plate boundaries. The tectonic plates ride on top of the asthenosphere, the solid but less-viscous part of the upper mantle that can flow and move along with the plates, and their motion is strongly coupled with patterns convection inside the Earth's mantle. An example of this is the Nazca plate being subducted under the South American plate to form the Andes Mountain Chain.

fracturing rocky soil before treatment

fracturing is a way to crack rock or very dense soil, like clay, below ground. It is not necessarily a cleanup method in itself. Rather, fracturing is used to break up the ground to help other cleanup methods work better. The cracks, which are called fractures, create paths through which harmful chemicals can be removed or destroyed.

Hydraulic fracturing uses a liquid?usually water. The water is pumped under pressure into holes drilled in the ground. The force of the water causes the soil (or sometimes rock) to crack. It also causes existing fractures to grow larger. To fracture soil at greater depths, sand is pumped underground with the water. The sand helps prop the fractures open and keep them from closing under the weight of the soil.

Pneumatic fracturing uses air, to fracture soil. It also can help remove chemicals that evaporate or change to gases quickly when exposed to air. When air is forced into the soil, the chemicals evaporate and the gases are captured and treated above ground.

Air can be forced into the ground at different depths within a hole. When air is forced near the ground surface, the surface around the holes may rise as much as an inch, but will settle back close to its original level. In both pneumatic and hydraulic fracturing, equipment placed underground directs the pressure to the particular zone of soil that needs to be fractured.

Blast-enhanced fracturing uses explosives, such as dynamite, to fracture rock. The explosives are placed in holes and detonated. The main purpose is to create more pathways for polluted groundwater to reach wells drilled for pump and treat cleanup.

Source: US-EPA, Clu-In: http://www.clu-in.org/techfocus/default.focus/sec/Fracturing/cat/Overview/

Good Laboratory Practice (GLP)

Good Laboratory Practice (GLP) is a quality system concerned with the organisational process and the conditions under which non-clinical health and environmental safety studies are planned, performed, monitored, recorded, archived and reported. (Source: REACH Glossary)
OECD Guidelines on Good Laboratory Practice part 1, available at: http://www.oecd.org/findDocument/0,2350,en_26...

Good Laboratory Practices (GLP)1

GLP = Good Laboratory Practices
According to 2004/10/EC, Good Laboratory Practice (GLP) is defined as a quality system concerned with the organizational process and the conditions under which non-clinical health and environmental safety studies are planned, performed, monitored, recorded, archived and reported. The main objective of GLP is to ensure test data produced by different laboratories can be mutually recognized so as to avoid repeat testing. GLP provides an assurance to regulatory authorities that the data submitted are a true reflection of the results obtained during the study and can therefore be relied upon when making risk/safety assessments.

Member States of the European Union have to take measures to comply with the principle of GLP when evaluating chemicals safety according to 67/548/EEC. SGS has a worldwide network of laboratories that are GLP compliant contractual laboratories for physico-chemical, toxicological and ecotoxicological tests.

Source: REACH, Glossary

grain size fractioantion of sediments
grain size fractionation as soil remediation technology
groundwater extraction plant
indirect abstraction of groundwater
interaction between chemical substances and receptors
liquid/liquid extraction

an extraction technique (LLE) in which one liquid is shaken with or contacted by an extraction solvent to transfer molecules of interest into the solvent phase. Typical sample preparation (concentration) method e.g. organic contaminants in water are extracted into an organic solvent to be measured by gas or liquid chromatography.

membrane assisted solvent extraction
chemical extraction using polypropylene membrane filled with organic solvent and placed into the aqueous sample. Sample preparation method for chromatography based on liquid/liquid extraction procedure where the phases are separated by the membrane. It can be fully automated. Typical applications: extraction of extractable hydrocarbons (EPH), PAHs, phenols, PCBs, pesticides from water or aqueous suspensions. Suitable for analytes to be extracted from extremely dirty matrices. (Source: B. Hauser, M. Schellin, and P. Popp: Membrane-Assisted Solvent Extraction of Triazines, Organochlorine, and Organophosphorus Compounds in Complex Samples Combined with Large-Volume Injection-Gas Chromatography/Mass Spectrometric Detection. Anal. Chem. 76, 6029-6038, 2004)
Micro Extraction by Packed Sorbent
sample preparation method for chemical analysis, e.g. for chromatography, abbreviated as MEPS. In principle it is a solid phase extraction (SPE) technique in miniaturized form: needs less sample, less solvents. The MEPS cartridge contains 2-3 mg solid packing, which can be C2, C8, C18, ion-exchange or unmodified silica phase. The MEPS cartridge is built into the syringe (of 10-250 microliters) needle. Pumping the sample through the cartridge the target compounds can be adsorbed on the stationary phase. Washing with solvent the interfering matrix components can be removed, the analyte concentrated can be eluted into LC or GC. Typical applications: determination of PAHs, pesticides, PCBs in volume-limited aqueous samples. (Source: www.labhut.com/docs/static/autosamplers/meps.pdf)
microwave extraction
chemical extraction assisted by microwave energy, can be used e.g. for extracting contaminants from soil prior to analysis. The process is faster than the conventional extraction methods, more economic as the cost of solvents is reduced, more environmental friendly due to the lower solvent need. The equipment is expensive but thousands of extractions can be carried out. The parameters are controlled by software resulting in good reproducibility.
multi-phase extraction of contaminated soil

multi-phase extraction uses a vacuum system 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. Contaminants in the newly exposed vadose zone are then accessible to vapor extraction. Once above ground, the extracted vapors or liquid-phase organics and ground water are separated and treated.

Source: US-EPA, Clu-In:http://www.clu-in.org/techfocus/default.focus/sec/Multi-Phase_Extraction/cat/Overview/

phytoextraction
protected water extraction plant
RAC

the Committee for risk Assessment (RAC) is an Agency committee that is responsible for preparing the opinion of the Agency on evaluations, applications for authorisation, proposals for restrictions and proposals for classification and labelling under the classification and labelling inventory task and any other questions that arise from the operation of this Regulation relating to risks to human health or the environment. The RAC consists of at least one but no more than two members from the nominees of each Member State appointed by the Management Board for a renewable term of three years. The Committee members may be accompanied by advisers on scientific, technical or regulatory matters. (Source: REACH Glossary)

RACE
Risk Abatement Center for Contaminated soil in CEE Countries
Risk Assessment Committee (RAC), REACH

the Committee for risk Assessment (RAC) is an Agency committee that is responsible for preparing the opinion of the Agency on evaluations, applications for authorisation, proposals for restrictions and proposals for classification and labelling under the classification and labelling inventory task and any other questions that arise from the operation of this Regulation relating to risks to human health or the environment. The RAC consists of at least one but no more than two members from the nominees of each Member State appointed by the Management Board for a renewable term of three years. The Committee members may be accompanied by advisers on scientific, technical or regulatory matters.

(Source: REACH)

Risk Characterisation (RC)

final step in chemical safety assessment, it consists of estimation of the incidence and severity of the adverse effects likely to occur in a human population or environmental compartment due to actual or predicted exposure to a substance. It may include a “risk estimation”, i.e. the quantification of that likelihood. risk characterisation is made for each exposure scenario and for each target population or compartment. (Source: REACH Glossary)

size fraction
soil characteristics suitable for toxicity testing
soil extraction
soil fracturing

soil fracturing is an enhancement technology designed to increase the efficiency of other in situ technologies in difficult soil conditions. The fracturing extends and enlarges existing fissures and introduces new fractures, primarily in the horizontal direction. When fracturing has been completed, the formation is then subjected to vapor extraction, either by applying a vacuum to all wells or by extracting from selected wells, while other wells are capped or used for passive air inlet or forced air injection. Technologies commonly used in soil fracturing include pneumatic fracturing (PF) and hydraulic fracturing. Fracturing is applicable to the complete range of contaminant groups with no particular target group. The echnology is used primarily to fracture silts, clays, shale, and bedrock.

Source: EURODEMO Project

soil gas and vapour extraction and its treatment on the surface
soil gas extraction
soil vapour extraction: SVE

soil vapor extraction SVE is used to remediate unsaturated vadose zone soil. A vacuum is applied to the soil to induce the controlled flow of air and remove volatile and some semivolatile organic contaminants from the soil. SVE usually is performed in situ; however, in some cases, it can be used as an ex situ technology.

soil vapour xtraction and its treatment on the surface