Pollution systems that evaluate potential

An evaluation of the factors affecting the reliability of the ammonium pyrrolidinecarbodithioate-methyl isobutyl ketone (APCD-MIBK) extraction system for Cd, Cu, Ni, Pb, and Zn in seawater established that pH control of the aqueous phase is important. The pH range 2.1 to 2.3 was the best for extracting these metals. In addition, the amount of APCD added was important both because of potential corn-petition reactions and because of metal contamination in the APCD reagent. The overall precision of the technique and the precision of the atomic absorption measurements were calculated. This technique can be used effectively in both clean coastal waters and more polluted harbor waters. 

This brief review of selected existing systems reveals that there are a number of methods that can be applied to site-specific situations or to evaluation of the pollution potential of existing sites. However, a planning tool is needed for use before the site-specific methods are employed. The system must (1) function as a management tool, (2) be simple and easy-to-use, (3) utilize available information, and (4) be able to be used by individuals with diverse backgrounds and levels of expertise. This document contains a system which attempts to meet these needs and to provide the planning tool necessary before site-specific evaluations. 

Inherent in each hydrogeologic setting are the physical characteristics which affect the ground-water pollution potential. Many different biological, physical and chemical mechanisms may actively affect the attenuation of a contaminant and, thus, the pollution potential of that system. Because it is neither practical nor feasible to obtain quantitative evaluations of intrinsic mechanisms from a regional perspective, it is necessary to look at the broader parameters which incorporate the many processes. After a complete evaluation of many characteristics and the mappability of the data, the most important mappable factors that control the ground-water pollution potential were determined to be ... 

To evaluate attributes for a process, the waste reduction (WAR) algorithm was developed initially as a pollution balance [46] and later as a potential impact balance [47]. The potential impact balance is a relative of toxicity indexes (e.g., [48]), which divide pollution by an LD50 (lethal dose that kills 50% of a test population) or threshold-limiting value. Flowever, the balance incorporates an input—output calculation of system analysis... 

Chemical mass transfer responsible for partitioning of contaminants constitutes a significant part of the processes involved in the transport and fate of contaminants. In the longer term, the redox environment (pE) and subsequent reduction-oxidation reactions will ultimately determine the final fate of the contaminants. The assessment of whether retention or retardation processes are responsible for the observed partitioning and hence the attenuation of contaminants within the soil matrix, is vital and critical in the evaluation of the natural attenuation capability of the soil barrier system. The dilemma facing both regulatory agencies and practitioners is obvious If potential pollution hazards and threats to public health and the environment are to be minimized or avoided, How can one ensure that the processes for contaminant attenuation in the substrate are the result of (irreversible sorption) retention... 

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