Aquifers pollution vulnerability

In the special case of rivers flowing across shallow aquifers, groundwater vulnerability to percolation of pollutants carried out by rivers is determined by two factors ... 

The distribution and the nature of past, existing and potential pollution sources have also to be thoroughly established and assessed in light of the pollution vulnerability of the aquifer system concerned. A general appreciation of the reactive processes which may take place during contaminant transport, in ah sub-surface compartments (soils, cappings layers, unsaturated and saturated zones in aquifers, river beds,. ..) is required too. 

Foster, S. S. D. 1987. Fundamental concepts in aquifer vulnerability, pollution risk, and protection strategy. In Vulnerability of soil and groundwater to pollutants, ed. W. Van Duijvenbooden and H. G. van Waegeningh. The Hague TNO Committee on Hydrological Research. 

Groundwater is abstracted from many different types of aquifers, some of which may be highly susceptible to pollution as a consequence of human activity. The vulnerability of groundwater sources is important when assessing the risks to groundwater posed by various activities, Some aquifers are protected by one or more layers of impermeable material, such as clay, that lie above the saturated zone and that will prevent or retard the transport of chemicals from their sources to the saturated zone. Also, aquifers at certain depths may be protected from chemicals (even from some naturally occurring chemicals) that may be present at other depths in the geological profile. 

Quantitative assessment of water-table aquifers vulnerability is being carried out when there is risk of bacteriological infechon. This method is based on groundwater downward time-of-travel during which percolated bacteria or polluted water may rich to water table. 

But the water pollution debates of the early decades of the twentieth century focused mostly on surface waters. Aquifers are less vulnerable than... 

In general, shallow aquifers are more vulnerable than deeper aquifers (but much less vulnerable than surface waters) to pollution. Deep aquifers are indeed generally better... 

In the case of lakes overlying shallow aquifers, die groundwater vulnerability to polluted lake water is determined in a similar way as for rivers often, however, the vertical hydraulic gradients tend to display a greater stability through time in these cases. 

Robins, N.S. (Ed.). 1998. Groundwater Pollution, Aquifer Recharge and Vulnerability, Special Publication No. 130. Geological Society, London. 

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