3.5.1
Capacity Test
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NOTE: This test should be used to verify that the
well is developed properly and will produce the
required yield. Test pump should be capable of a
range of pumping rates, varying from about 50
percent to about 200 percent of the design capacity
of the well. Since there are a wide variety of pump
test methods, the designer should refer to a good
water wells reference book (such as "Ground Water
and Wells," by Fletcher G. Driscoll, published by
Johnson Well Screens, 1986 ) for test procedures
which best apply.
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The Contractor shall furnish and install an approved temporary test pump,
with discharge piping of sufficient size and length to conduct the water
being pumped to [point of discharge][_____], and equipment necessary for
measuring the rate of flow and water level in the well. An [8] [_____]
hour [constant-rate] [step-drawdown] capacity test shall be run with the
pumping rate and drawdown at the pump well and observation wells recorded
every [[30] [_____] minutes] [1/2 minute during the first 5 minutes after
starting the pump; then every 5 minutes for an hour; then every 20 minutes
for 2 hours. From this point on, readings taken at hourly intervals, until
the water level stabilizes, shall be sufficient].[Observation wells
(piezometers) shall be read on the same schedule as the pump well.] [During
the step-drawdown test, the pumping rate shall be increased in steps at
[regular][[2][____] hour] intervals. Specific capacity shall be measured
for each step.] The test shall begin at the rate of [the expected capacity
of well][[_____] L/s [_____] gpm] and at least that rate maintained
throughout the duration of the [test] [step interval]. [The well shall be
"step" tested at rates of approximately [1/2, 3/4, 1 and 1 1/2][____] times
the design capacity of [_____] L/s [_____] gpm.]If this capacity cannot be
maintained for the test period, the capacity test shall be terminated and
the test hole drilled deeper or relocated as directed. When the pump is
shut off, water level readings shall be taken during the rebound period for
the same intervals of time as the drawdown test. The record of the test, in
triplicate, shall be delivered to the Contracting Officer.
3.5.2
Test for Plumbness and Alignment
Upon completion of the permanent well, plumbness and alignment shall be
tested by lowering into the well, to the total depth of the well, a plumb
[12] [_____] m [40] [_____] feet long or a dummy of the same length. The
outer diameter of the plumb shall not be more than 13 mm 1/2 inch smaller
than the diameter of that part of the hole being tested. If a dummy is
used, it shall consist of a rigid spindle with three rings, each ring being
[300] [_____] mm [12] [_____] inches wide. The rings shall be cylindrical
and shall be spaced one at each end of the dummy and one in the center.
The central member of the dummy shall be rigid so that it will maintain the
alignment of the axis of the rings. The dummy shall be decontaminated as
specified in paragraph Decontamination, before use. If the plumb or dummy
fail to move freely throughout the length of the casing or well screen for
the depth of well or should the well vary from the vertical in excess of
two-thirds the inside diameter of that part of the well being tested for
each 30 m 100 feet of depth, the plumbness and alignment of the well shall
be corrected by the Contractor. If the faulty alignment and plumbness is
not correctable, as determined by the Contracting Officer, the well shall
SECTION 02521
Page 31
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