EIA

Exploration activities are potentially damaging to the environment. The cutting down of trees in preparation for an onshore seismic survey may result in severe soil erosion in years to come. Offshore, fragile ecological systems such as reefs can be permanently damaged by spills of crude or mud chemicals. Responsible companies will therefore carry out an Environmental Impact Assessment (EIA) prior to activity planning and draw up contingency plans should an accident occur. In Section 4.0 a more detailed description of health, safety and environmental considerations will be provided. 

If no prior drilling activities have been recently carried out in the area, usually an environmental impact assessment (EIA) will be carried out as a first step. An EIA is usually undertaken to ... 

The objective of an EIA Is to document the potential physical, biological, social and health effects of a planned activity. This will enable decision makers to determine whether an activity is acceptable and if not, identify possible alternatives. Typically, ElA s will be carried out for... 

The time taken to complete a base line study and EIA should not be underestimated. The baseline study describes and inventorises the natural initial flora, fauna, the aquatic life, land and seabed conditions prior to any activity. In seasonal climates, the baseline study may need to cover the whole year. The duration of an EIA depends upon the size and type of area under study, and the previous work done in the area, but may typically take six months. The EIA is often an essential step in project development and should not be omitted from the planning schedule. 

Certain key stages in the EIA process have been adopted by many countries. These broad stages reflect what is considered to be good practice within environmental assessment and include ... 

Screening undertaken to decide which projects should be subjecHo environmental assessment. Screening may be partly determined by local EIA regulations. Criteria used include threshold, size of project, and sensitivity of the environment. 

Scoping identifies, at an early stage, the most significant issues to be included in the EIA. Many early ElAs were criticised because they were encyclopaedic and included irrelevant information. 

EIA Preparation is the scientific and objective analysis of the scale, significance and importance of impacts identified. Various methods have been developed, in relation to baseline studies impact identification prediction evaluation and mitigation, to execute this task. 

Public consultation and participation aims to assure the quality, comprehensiveness and effectiveness of the EIA, as well as to ensure that the public s views are adequately taken into consideration in the decision-making process. 

EIS presentation a vital step in the process, the documentation serves to communicate the findings of the EIA process to interested parties. 

One particular common piece of legislation worth noting is the requirement for an Environmental Impact Assessment (EIA) to be performed prior to any appraisal or development activity. An EIA is used to determine what impact an activity would have on the natural environment (flora, fauna, local population), and will be used to modify the activity plan until no negative impact is foreseen. More details of the EIA are given in Section 4.0. 

Prepared from the commercially available eia-diol and thionylchloride. 

State Energy Price and Expenditure Report 1990, DOE/EIA-0376(90), U.S. Departmeat of Eaergy, Eaergy Information Administration, Washiagtoa, D.C.,Sept. 1992. 

Estimates ofE.S. Wood Energy Consumption 1980—1983, DOE/EIA-O341(83), U.S. Department of Energy, Energy Information Administration,... 

Pu/p and Paper Indust s Energy Ese-Cakndar Year 1986 New York, Apr. 20,1987 J. C. NiceUo, US. Pulp and Paper Industry s Energy Use-Calendar Year 1987 New York, May 17, SinnualEnerg) Eeview 1987 DOE/EIA-0384(87). U.S. Department of Energy, Energy Information Administration,... 

HnnualEnergy Outlook, report no. DOE/EIA-0383 (92), Energy Information Administration, U.S. Dept, of Energy, Washington, D.C., 1992. 

Ref. 277 unless otherwise noted gc = gas chromatography hplc = high pressure Hquid chromatography ir = infrared spectroscopy uv = ultraviolet spectroscopy glc = ga sliquid chromatography eia = enzyme immunoassay vis = visible spectroscopy. 

Turbidimetric Agglutination Immunoassays. Agglutination—precipitation immunoassays were among the first practical appHcations of the antigen—antibody reaction in diagnostic tests. These assays are not as widely used in the 1990s as EIA and FIA because they are either not quantitative enough or lack the sensitivity limits of RIA, EIA, and EIA. 

Enzyme Immunoassay. In EIA, antibody (or antigen) is labeled with (or conjugated to) an enzyme, and this reagent is used to complex and quantify the target antigen (or antibody) in a sample. Conjugation may utilize a variety of chemical methods. 

The primary use of EIA when it was first developed was for histological labeling and localization of specific cell macromolecules. Eor example, enzymes labeled with peroxidase were used to locate specific cellular compartments and stmctures for microscopic examination. The flexibiUty of EIA was recognized quickly and it was adapted for use as a laboratory assay. 

The specific enzyme to be used in an EIA is deterrnined according to a number of parameters including enzyme activity and stabiUty (before, during, and after conjugation), cost and availabiUty of the enzyme substrate, and the desired end point of the EIA, such as color. Most EIAs utilize a colored end point which can be readily deterrnined both visually and spectrophotometricaHy. Table 1 Hsts a number of enzymes which have been used in immunoassays and their substrates. 

EIAs can be used per se or with a spectrophotometer. Traditionally, EIAs have been developed in 96-weU microtiter plates which provide the immobilization support for the assay, the reaction vessel, and, when linked to a spectrophotometer-based reader, a rapid means to detect and quantify the color resulting from interaction of a substrate with the antibody—antigen—enzyme complex. Automated immunoassay analyzers targeted primarily for use in the clinical laboratory have taken automation one step further, utilizing robotics to carry out all reagent additions, washings, and final quantification including report preparation. 

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