Soil pore water

The majority of trichloroethylene present on soil surfaces will volatilize to the atmosphere or leach into the subsurface. Once trichloroethylene leaches into the soil, it appears not to become chemically transformed or undergo covalent bonding with soil components. When trichloroethylene was absorbed onto kaolinite and bentonite, the nuclear magnetic resonance (NMR) spectra showed no evidence of chemical reactions (Jurkiewicz and Maciel 1995). Because trichloroethylene is a dense nonaqueous phase liquid, it can move through the imsaturated zone into the saturated zone where it can displace soil pore water (Wershaw et al. 1994). 

Wershaw RL, Aiken GR, Imbrigiotta TE, et al. 1994. Displacement of soil pore water by trichloroethylene. J Environ Qual 23 792-798. 

As more sensitive analytical methods for pesticides are developed, greater care must be taken to avoid sample contamination and misidentification of residues. For example, in pesticide leaching or field dissipation studies, small amounts of surface soil coming in contact with soil core or soil pore water samples taken from further below the ground surface can sometimes lead to wildly inaccurate analytical results. This is probably the cause of isolated, high-level detections of pesticides in the lower part of the vadose zone or in groundwater in samples taken soon after application when other data (weather, soil permeability determinations and other pesticide or tracer analytical results) imply that such results are highly improbable. 

In eight contaminated soils with pH 7.05-8.20 from eastern and southern Australia, soluble Zn, Cu and Cd concentrations in soil pore water are 0.19-422, 36-4840, and 7.2-4260 pM, respectively (Nolan et al., 2003). 

Haswell, S.J., P. O Neill, and K. C Bancroft. 1985. Arsenic speciation in soil-pore waters from mineralized and unmineralized areas of south-west England. Talanta 32 69-72. 

Recently, Burkhard (2000) reviewed contaminant sorption by dissolved organic matter. Using several hundreds of UCC-water partition coefficients (A doc) reported in these studies, he found that UCC-water partition coefficients for naturally occurring DOC (humic and fulvic acids, sediment pore water, soil pore water, groundwater, and surface water) was best described by... 

The Arctic Foundations, Inc. (AFl), frozen soil barrier technology is constructed by artificially freezing the soil pore water. As the pore water freezes, the soil permeability decreases, thereby forming an impermeable barrier that surrounds and contains the contaminants. When properly installed, the frozen soil barrier prevents the migration of contaminants within groundwater and soil. Contaminants are contained in situ, with the frozen native soils serving as the containment medium. The contaminants are isolated by the wall until appropriate remediation techniques can be applied. 

Ross et al. [6] analysed samples of soil leachates from laboratory columns and of soil pore water from field porous cup lysimeters for aluminium by atomic absorption spectrometry under two sets of instrumental conditions. Method 1 employed uncoated graphite tubes and wall atomisation method 2 employed a graphite furnace with a pyrolytically coated platform and tubes. Aluminium standards were prepared and calibration curves used for the colorimetric quantification of aluminium. Method 1 gave results which compared favourably with method 2 in terms of both sensitivity and interference reduction for samples containing 1-15 uM aluminium. 

Brown et al. [270] applied high performance liquid chromatography to the determination of organocopper speciation in soil-pore waters. 

Di Bonito, M., Breward, N., Crout, N., Smith, B., and Young, S. (2008). Soil pore water extraction methods for trace metals determination in contaminated soils. In Environmental Geochemistry Site Characterization, Data Analysis, and Case Histories (B. De Vivo, H. E. Belkin, and A. Lima, eds.). Elsevier Science Publishers, Amsterdam, The Netherlands. 

Overview of Selected Soil Pore Water Extraction Methods for the Determination of Potentially Toxic Elements in Contaminated Soils Operational and Technical Aspects... 

Chemical elements that are either present naturally in the soil or introduced by pollution are more usefully estimated in terms of availability of the element, because this property can be related to mobility and uptake by plants. A good estimation of availability can be achieved by measuring the concentration of the element in soil pore water. Recent achievements in analytical techniques allowed to expand the range of interest to trace elements, which play a crucial role both in contaminated and uncontaminated soils and include those defined as potentially toxic elements (PTE) in environmental studies. A complete chemical analysis of soil pore water represents a powerful diagnostic tool for the interpretation of many soil chemical phenomena relating to soil fertility, mineralogy and environmental fate. This chapter describes some of the current methodologies... 

Overview of Selected Soil Pore Water Extraction Methods... 

Both phases represent what can be defined as soil pore water this term is preferred to the more specific soil solution and will be used throughout this chapter. 

To assess the environmental bioavailability, mobility and geochemical cycling of trace elements in soil, analyses of soil pore water composition are frequendy more instructive than those from whole soil or soil extracts. The validity of this concept... 

The validity of these assumptions depends on the way that soil pore water is conceptualized, that is, defined and sampled, and how that concept is translated into an operational method or model whereby soil pore water can be obtained and its... 

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