The Exploitation of Aquifers - Hydrogeology: Objectives, Methods, Applications - page 179

C HAPTER C2
The Exploitation of Aquifers
1 PRELIMINARY RESEARCH
￿ Any search for a new water resource must take into account the desired
use, the stated demand, and the spatial limits of search area.
Water to be used as a potable resource must conform to the physical and
chemical standards required by sanitary regulation. Other uses hold
less stringent standards, but often have their own quality criteria. For
industrial uses, water must be neither corrosive, abrasive, nor too likely
to create mineral deposits; its use in heating or air conditioning systems
requires that its temperature allows heat transfers; in agriculture, its
electrical conductivity, sulfate and chloride contents, must not be too
high.
Water demand can be highly variable, depending on the use: from a
few m 3 ·day -1 for a single residence to several hundreds or thousands
of m 3 per hour for collective supplies or for industrial or agricultural
uses. Demand can also vary greatly over time, with peak consumption
sometimes 5 to 10 times greater than the average.
The size of the area under investigation also infl uences the options to
be considered. While the search is often limited to a single possibility
when the area is constrained, it can, on the other hand, offer multiple
opportunities and allow the choice of an optimal aquifer and
exploitation site when there is a vast territory to be explored.
￿ The hydrogeologic study is undertaken based on the given objectives, in
order to identify appropriate aquifers, to allow an objective comparison
between the various potential solutions, and to propose the most
favorable site.
Specifi c investigations then allow the determination of the most
effective catchment system, and the evaluation of the project's
productivity and its possible environmental impacts.