Leaching of Contaminants to Groundwater - Dealing with Contaminated Sites: From Theory Towards Practical Application - page 840

the effects of both physical factors (water content, flow velocity, textural interfaces)
and chemical processes (ionic strength, solution composition, p H) on colloid reten-
tion and mobilization, and modeling colloid-facilitated transport during conditions
of transient flow.
Also, to the best of our knowledge, no models are currentely available that con-
sider all of the many processes simultaneously and in their full complexity, including
their mutual interactions. That is, no models exist that consider transient preferen-
tial flow and transport in structured soils or fractured rocks, while simultaneously
considering complex biogeochemical reactions between contaminants, organic and
inorganic colloids and/or organic complexes, and solid and air phases of a soil,
including widely varying rates of these various reactions. Further integration of the
different types of numerical models is needed to address practical problems of con-
taminant transport (trace elements, radionuclides, organic contaminants) in complex
vadose zone environments.
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doi:10.1029/2002WR001340