Module 4 — Water Well Drilling Agreements
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10.
Type of drilling__________________________________________________________________
11.
Diameter of hole_________________________________________________________________
The type of drilling equipment, aquifer composition, yield required and depth determine
the type of well produced. Rotary drilled and cable tool drilled wells are typically100-200 mm
(4-8
in.) in diameter; bored wells range in diameter from 45-90cm (12-36 in.). The water well
drilling industry is required by law to construct wells with casings 102mm (4in.) or more to
accommodate submersible pumps.
12.
Flowing well control_ ____________________________________________________________
In cases where a flowing well is anticipated, provision must be made to equip the well
with a flow control device that allows the flow to be shut off completely and to prevent freezing.
13.
Well connection_ ________________________________________________________________
Where the connection of the pumping equipment to the well casing is made below the
ground surface, a pitless adaptor is required under the Water (Ministerial) Regulation. Well
pits are no longer permitted. If a jet pump is being used, a pump house that houses only the
well and the pumping equipment is allowed.
14.
Formation logging procedure_ ____________________________________________________
Logging the geological formations during drilling provides key information about aquifer
location and quality. This information is especially important to accurately place well screens.
There can be several types of formation logging.
Descriptive logging records the material encountered as drilling proceeds (lithology).
Electric logging, or E logging, verifies and supplements descriptive logging. It can
only be performed in an uncased hole that is filled with drilling fluid. Basically it
reveals the character of the material and relative quality of water in the formation.
A limited number of licensed water well contractors in Alberta possess this equipment.
Gamma-ray logging can be performed in cased holes without drilling fluid and
reveals the character of the material present. Very few licensed water well contractors
in Alberta have this equipment. A combination of descriptive logging and electric or
gamma-ray logging provides very accurate information about the formations through
which the well is constructed.
Pitless Adaptor
N / A
Rotary
158
mm (6 1/4" ) and 124 mm (4 7/8" )