In unsaturated zone

The pump-and-treat method is comparable to soil flushing. In fact, the pump-and-treat method can treat both groundwater and aquifer soil at the same time, and can also be directly applied to unsaturated soil zones. The soil flushing method is mainly considered as a treatment in unsaturated zones. 

Water Movement in Unsaturated Zone of Soil Formation. 701... 

Carsel, R.F., Nixon, W.B., and Ballantine, L.G. Comparison of pesticide root zone model predictions with observed concentrations for the tobacco pesticide metalaxyl in unsaturated zone soils. Environ. Toxicol Chem., 5(4) 345-353,1986. 

Calvet R (1984) Behavior of pesticides in unsaturated zone. Adsorption and transport phenomenon. In Yaron B, Dagan G, Goldschmid J (eds) Pollutants in porous media. Springer, Heidelberg, pp 143-151... 

Immiscible phase — Contaminants are present as nonaqueous-phase liquids (NAPLs), primarily in unsaturated zones. 

Juracek, K.E. and E.M. Thurman (1997). Assessing aquifer contamination risk using immunoassay Trace analysis of atrazine in unsaturated zone sediments. J. Environ. Qual., 26 1080-1089. 

Characterisation of potential pollutants and any parameters indicative of pollution, including description of the properties which influence their fate and transport, e.g. transport tlirough and out of the aquifer, including transport in unsaturated zone, the behaviour of hydrogeochemical environments, ecotoxicology and toxicology, and possible impacts on ecosystems. 

For the purpose of transport modeling, measured GO2 losses to unsaturated sediments were quantified by Freundlich isotherms for a PGO2 range commonly present in unsaturated zones (400 t 4000 Pa). The isotherms define the moles of dissolved plus adsorbed GO2 /m of sediment surface (GO2) associated with the deposits in which onsite measurements were made ... 

Co-contaminants Dispersion Dilution Environment Chemical composition Sorbents Microorganisms Nutrient offer Microbiological decay/metabolism Gas transfer in unsaturated zone... 

Sililo, O. T. N. Tellam, J. H. Fingering in Unsaturated Zone Flow A Qualitative Review with Laboratory Experiments on Heterogeneous Systems. Growidwatej tiW, 38 (6), 864. 

The approach is very commonly used in transport models because mathematically it is relatively easy to incorporate. Goyette and Lewis [28] highlighted the utihty of values in screening level ground water contaminant transport models of inorganic ions with the caution that experimental conditions such as pH, electrolyte composition and soil type are similar to those being modeled. Viotti et al. [29] used values to model phenol transport in an unsaturated soil. Schroeder and Aziz [30] used this approach to account for PCBs sorption into dredged materials. Buczko et al. [31] used the Freundlich approach to model chromium transport in unsaturated zone. 

Above treatment is simplified one. However, natural system is more complicated. For instance, fluids are compressive, fluids flow under non-steady state conditions, and permeability of rocks is heterogeneously distributed. Fluids flow not only in saturated zone, but also in unsaturated zone. 

Thorstenson, D. C. and D. W. Pollock. 1989. Gas transport in unsaturated zones Multi-component systems and the adequacy of Pick s Laws. Water Resources Research 25, 477-507. 

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