Lexikon
"surface water status" is the general expression of the status of a body of surface water, determined by the poorer of its ecological status and its chemical status.
"ecological status" is an expression of the quality of the structure and functioning of aquatic ecosystems associated with surface waters, classified in accordance with Annex V. of the Water Framework Directive (WFD), 60/2000/EC
"good surface water chemical status" means the chemical status required to meet the environmental objectives for surface waters established in Article 4(1)(a) of WFD (60/2000/EC) that is the chemical status achieved by a body of surface water in which concentrations of pollutants do not exceed the environmental quality standards established in Annex IX and under Article 16(7), and under other relevant Community legislation setting environmental quality standards at Community level.
"good ecological potential" is the status of a heavily modified or an artificial body of water, so classified in accordance with the relevant provisions of Annex V. of Water Framework Directive (WFD), (60/2000/EC).
"good ecological status" is the status of a body of surface water, so classified in accordance with Annex V. of WFD (Water Framework Directive), 60/2000/EC
Surfactant Enhanced Aquifer Remediation (SEAR), in its most basic form, could thus be considered a chemical enhancement to pump and treat. A chemical solution is pumped across a contaminated zone by introduction at an injection point and removal from an extraction point. To cover the entire contaminated zone, a number of injection and extraction wells are used; the well configuration is determined by the subsurface distribution of NAPL and the hydrogeologic properties of the aquifer.
SEAR is a source zone remediation technology. SEAR removes the residual phase contamination from which the dissolved phase plume is derived. Free phase contamination is typically removed by conventional pumping before SEAR is employed. SEAR does not have an immediate effect on the dissolved phase plume concentrations and is not a dissolved phase plume remediation technology. Removal of the source does however cause an intermediate and long-term reduction in dissolved phase contaminant concentrations.
Surfactants are unique chemical agents that greatly enhance the solubility of organic contaminants in aqueous media. They are also able to reduce the interfacial tension (IFT - that force existing where two fluids meet that keeps them as separate fluids) between the aqueous and organic phases to mobilize the organic phase. To illustrate the two mechanisms, we can use the familiar examples of the cleaning action of household cleaning detergents, which contain surfactants as a common constituent. We have witnessed surfactant-induced solubilization in the oily solution resulting from soaking oily pots and pans in dish detergent; we have observed a reduction in IFT from oil droplets or a sheen of oil coming off the pan due to the presence of a detergent. A surfactant flood can be designed to remove contaminants either primarily by solubilization or primarily by mobilization. Surfactant mobilization can remove more DNAPL in less time; however, there is greater risk of uncontrolled downward movement of DNAPL, as DNAPL is being physically displaced by the surfactant solution. Thus, to conduct a mobilization flood, it is necessary to have an aquitard as a barrier to prevent vertical DNAPL migration. It is important to identify from the outset whether solubilization or mobilization of DNAPL is desired, because not all surfactants can be used to conduct a mobilization flood.
The primary objective in SEAR design is to remove the maximum amount of contaminant with a minimum amount of chemicals and in minimal time while maintaining hydraulic control over the injected chemicals and contaminant. Each step in the design process must keep this in mind. Design challenges include precisely locating the DNAPL, finding the optimum surfactant solution for a given DNAPL composition and soil type, and fully characterizing the hydraulic properties of the aquifer, particularly the heterogeneities typically present in the subsurface environment. Because it is impossible to know with certainty the variations in aquifer properties over the treatment zone, numerical modeling tools are used to simulate how the system may respond in the presence of these unknown factors. Numerical modeling is also necessary to understand the dynamics of the flooding process under the hydrogeologic conditions at the site. SEAR has been acknowledged to be a promising, innovative technology for the removal of DNAPLs primarily because of the history of the use of surfactant-enhanced oil recovery by the petroleum industry.
Source: http://www.cpge.utexas.edu/ee/sear.html
a biologic response to multiple substances where one substance worsens the effect of another substance. The combined effect of the substances acting together is greater than the sum of the effects of the substances acting by themselves.
See also additive effect and antagonistic effect.
a tablet PC (personal computer) is a tablet-sized computer that also has the key features of a full-size personal computer. A tablet PC is essentially a small laptop computer, equipped with a rotatable touchscreen as an additional input device, and running a standard (or lightly adapted) PC operating system like Windows or Linux.
Source: http://en.wikipedia.org/wiki/Tablet_personal_computer
target organ effects indicate which bodily organs are most likely to be affected by exposure to a chemical substance.The classes of target organ effects are summarized in the table below.
The following is a target organ categorization of effects which may occur, including examples of signs and symptoms and chemicals which have been found to cause such effects. These examples are presented to illustrate the range and diversity of effects and hazards found in the workplace, and the broad scope employers must consider in this area, but are not intended to be all-inclusive.
In the table we give the type of chemical substance and its organ-specific effect, the signs and symptoms, and some chemical substances as examples.
| Hepatotoxins - produce hepatic (liver) damage | jaundice, liver enlargement | Carbon tetrachloride, nitrosamines |
| Nephrotoxins - produce kidney damage | edema, proteinuria | Halogenated hydrocarbons, uranium |
| Neurotoxins - produce their primary toxic effects on the nervous system | narcosis, behavioral changes, decrease in motor functions | Mercury, carbon disulfide |
| Hemato-poietic agents - act on the blood or hemato-poietic system, decrease hemoglobin function, deprive the body tissues of oxygen | cyanosis, loss of consciousness | Carbon monoxide, cyanides |
| Agents which damage the lung - these irritate or damage pulmonary (lung) tissue | cough, tightness in chest, shortness of breath | Silica, asbestos |
| Reproductive toxins - affect the reproductive capabilities including chromosomal damage (mutations) and effects on fetuses (teratogenesis) | birth defects, sterility | Lead, DBCP |
| Cutaneous hazards - affect the dermal layer (skin) of the body | defatting of the skin, rashes, irritation | Ketones, chlorinated compounds |
| Eye hazards - affect the eye or visual capacity | conjunctivitis, corneal damage | organic solvents, acids |
When working with chemical substances that have target organ effects it is critical to prevent exposure. This is especially true if you have a pre-existing condition, disease or injury to that particular organ.
While this environmnetal lexikon refers specifically to organs that can be damaged by a substance, the medical community also refers to organs targeted by diseases or other conditions. For example, the medical literature discusses target organ damage to the brain, heart and kidneys in the context of hypertension (high blood pressure). These target organ effects can manifest themselves even before hypertension is diagnosed or progresses from the pre-hypertensive state. Other diseases/conditions target other organs, of course.
Source: http://www.ilpi.com/msds/osha/1910_1200_APP_A.html#targetorgan
In addition, the term technical dossier is also used to refer to one of the two parts of the Annex XV dossier. It supports the Annex XV report.(Source: REACH Glossary)
conversion between Celsius and Fahrenheit:
| degrees Celsius | degrees Fahrenheit | multiply by 1.8 and add 32 |
| degrees Fahrenheit | degrees Celsius | subtract 32 and divide by 1.8 |
terrestrial carbon sequestration is the process through which carbon dioxide (CO2) from the atmosphere is absorbed by trees, plants and crops through photosynthesis, and stored as carbon in biomass (tree trunks, branches, foliage and roots) and soils. The term "sinks" is also used to refer to forests, croplands, and grazing lands, and their ability to sequester carbon. Agriculture and forestry activities can also release CO2 to the atmosphere. Therefore, a carbon sink occurs when carbon sequestration is greater than carbon releases over some time period.
terrestrial toxicology concentrates on the terrestrial ecosystem. It measures the effect of hazardous chemical substances and physical agents on the memebers of the ecosystem and on the whole ecosystem structure.
thermally enhanced recovery is an in situ treatment process that uses heat to increase the volatilization rate of organics and facilitate extraction. Volatilized contaminants are typically removed from the vadose zone using soil vapor extraction. Specific types of thermally enhanced recovery techniques include radio frequency heating, conductive heating, steam heating, in situ steam stripping, hot air injection, dynamic underground stripping, in situ thermal desorption, and electrical resistive heating. Thermally enhanced recovery is usually applied to contaminated soil but may also be applied to groundwater.