tailieunhanh - EVALUATING THE SUBSURFACE FATE OF ORGANIC CHEMICALS OF CONCERN USING THE SESOLL ENVIRONMENTAL FATE MODEL

A food may test positive for glucose but not have enough glucose to taste sweet, or the sweet flavor may be masked, . by a sour flavor. Sweet foods may have little glucose, but significant amounts of other sugars (or artificial sweeteners that bind to taste receptors for sugars). When there is a small amount of a type of molecule (. fat in pretzels) the tests used in this activity may not be sensitive enough to read positive. The results of the protein test for pretzels may be somewhat ambiguous, but if a little bit of pretzel is crushed. | EVALUATING THE SUBSURFACE FATE OF ORGANIC CHEMICALS OF CONCERN USING THE SESOIL ENVIRONMENTAL FATE MODEL Edwin J. Fleischer Richard R. Noss Paul T. Kostecki Edward J. Calabrese Department of Civil Engineering University of Massachusetts Amherst MA 01003 Division of Public Health University of Massachusetts Amherst MA 01003 Abstract The heavy use and transport of petroleum products and other hydrocarbons create a high risk of contamination to soil and ground water systems. The problem caused by hydrocarbon spillage or disposal Is complex for scientists and regulatory officials alike. The Massachusetts Department of Environmental Quality Engineering has initiated a research project at the University of Massachusetts concentrating on the environmental and health effects of reuse and disposal options for petroleum contaminated soils. A major part of the risk assessment process is the determination of the potential routes or exposure for the various hydrocarbon constituents present in petroleum products. Research efforts have centered on eighteen specific contaminants because of their use as constituents in petroleum products their prevalence in the subsurface environment and their potential toxicity. The potential fate of these organic chemicals was examined by conducting computer simulations using the unsaturated zone environmental fate model SESOIL. The screening process was accomplished by running a series of one year simulations using typical Massachusetts climatic data and with a hypothetical sandy soil. The model results indicate the percentage of the total pollutant mass applied that can be expected to volatilize be adsorbed onto soil or leached to ground in one year s time. The 18 organic compounds evaluated can be divided into four groups those that preferentially adsorb onto soil particles those that volatilize rapidly those that pose a strong and immediate threat to ground water supplies and those for which no single pathway predominates. Screening a large .