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jksweets
Apr 16, 2012, 06:19 PM
A) a confined aquifer will rise in the well
Above the elevation at which was first
Encountered.

B) The water table is flat, featureless sur-
Face between the zones of aeration and
Saturation.
C) The water in a well drilled into an uncon-
Fined aquifer will rise to the elevation of
The water table.
Which of the preceding statements is/are
True?

sean_s
Apr 17, 2012, 01:10 PM
water table is not necessarily flat .so B is not true.
if the aquifer is unconfined, then the entry zones are at gauge pressure = 0, and that is the definition of local water table, from static height law of free fluid (gauge pressure are same at same depth anywhere in connected fluid body, with pressure = 0 at depth = 0), it will rise so up to watter table. C is true.

usually confined aquifers have pressure built in them, usually because of there structure (water entering only from a distance, and expanding the clay/rock intergrain space matrix to get stored) and will cause it to rise above where it is encountered. HOWEVER, in the region where water enters, called recharge zone, a confined aquifer behaves unconfined. In that place, water will not climb above water table or gauge pressure height zero. So I if you know by "confined" the location far away from recharge zone is meant, then A is true