Transportation groundwater samples

MW ultrafilter) were also collected. Two 50 unfiltered groundwaters samples were also collected and stored anaerobically in Al-containers with a special coating (Sigma Coating 9255-0300) to prevent contamination during transportation and storage. Further samples included 25 of 1 pm prefiltered and acidified water for U/Th isotopic analysis and 1 pm prefilters preserved for the U/Th analysis of particulates. 

Soil and groundwater samples from fuel oxygenate contaminated sites were obtained from different geographical locations, transferred into sterile, airtight flasks and transported to the laboratory in refrigerated containers. Samples were used immediately upon arrival for biodegradation potential assessment or for chemical analysis of fuel oxygenate concentrations (Table 2). Samples for molecular analysis were maintained frozen until used. 

Abstract In the construction of underground repositories for the disposal of potentially toxic wastes, it is critical to the development of a safety case that the chemical composition of waters flowing through the proposed containment barrier is fully understood. Because the barrier material is usually chosen to have low permeability, to minimize the risk of long-term transport of toxic material into the biosphere, it is often not possible to obtain sufficient flowing groundwater samples to allow complete hydrogeochemical characterization. In order to study the chemical composition of the water in these formations it is necessary, therefore, to use specialized pore-water extraction techniques. 

Suction lysimeters are required for some field-scale groundwater monitoring studies to monitor the transport of compounds of interest through the unsaturated zone. Unlike monitoring wells or water supply wells that sample water from the saturated zone, suction lysimeters sample water from the unsaturated zone. This section provides a summary of the installation and sampling procedures for pressure-vacuum suction lysimeters. A detailed discussion of unsaturated zone sampling devices is available elsewhere. 

Acrylonitrile is both readily volatile in air (0.13 atm at 23° C) (Mabey et al. 1982) and highly soluble in water (79,000 mg/L) (Klein et al. 1957). These characteristics dominate the behavior of acrylonitrile in the environment. While present in air, acrylonitrile has little tendency to adsorb to particulate matter (Cupitt 1980), so air transport of volatilized material is determined mainly by wind speed and direction. Similarly, acrylonitrile dissolved in water has only a low tendency to adsorb to suspended soils or sediments (Roy and Griffin 1985), so surface transport is determined by water flow parameters. Based on its relatively high water solubility, acrylonitrile is expected to be higly mobile in moist soils. In addition, acrylonitrile may penetrate into groundwater from surface spills or from contaminated surface water. The high vapor pressure indicates that evaporation from dry soil samples is expected to occur rapidly (EPA 1987). 

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