plumb line at the top of the well; however, this will not relieve the
Contractor of the responsibility of maintaining adequate clearance for
installation of the surging and pumping equipment required for testing and
pumping the wells. At least one plumbness check and alignment check shall
be performed on each well after placement of the filter pack. Additional
tests may be made during the performance of the work at the option of the
Contractor.]
[The well shall be constructed and all casing set round, plumb, and true.
The Contractor shall perform the following tests after the installation of
the well but prior to backfilling, and before its acceptance. Additional
tests may be made during the performance of the work at the option of the
Contractor. Should the Contractor fail to correct, at no additional cost
to the Government, any faulty alignment or plumbness disclosed as a result
of these tests, the Contracting Officer may refuse to accept the well. The
Contracting Officer may waive the requirements for plumbness if in his
judgement the Contractor has exercised all possible care in constructing
the well and the defect is due to circumstances beyond his control or if
the utility of the completed well is not materially affected or if the cost
of necessary remedial measures will be excessive. In no event will the
provisions with respect to alignment be waived.]
3.2.4.1
Plumbness
Plumbness shall be tested by use of a plumb line. The plummet shall be a
short cylinder with an outside diameter approximately 6 mm 1/4 inch smaller
than the inside of the well and/or temporary casing. It shall be suspended
from a small diameter wire rope and its point of suspension shall be in the
exact center of the plummet. The plummet shall be sufficiently heavy to
stretch the wire rope taut. The wire rope shall pass over a guide sheave
which shall be positioned at least 3 m 10 feet above the top of the well
and adjusted horizontally so that the plummet hangs in the center of the
well. Displacement of the wire rope during the plumbness check shall be
measured by means of a transparent plastic sheet on which a number of
concentric circles shall be scribed or drawn, and which is centered on the
top of the well. The exact center of these circles shall be marked, and
then a slot, slightly larger than the plumb line and extending from this
center to the edge, shall be cut in the plastic sheet. As the plummet is
lowered, any out-of-plumb condition of the well will be indicated by the
wire rope tending to drift away from the center, and the plastic sheet
shall be rotated until the slot is oriented in the direction of this drift,
while at all times maintaining the center of the concentric circles
coincident with the center of the well. Measurement of the amount of drift
shall be made along the edge of the slot for each increment by which the
plummet is lowered into the well. Drift at any depth shall be determined
by multiplying the measured plumb line displacement by the total length of
the plumb line and dividing the result by the fixed distance between the
guide sheave and the top of the well. If desired, alignment may be
calculated from the plumbness data in lieu of the alignment check described
in paragraph ALIGNMENT. Should the well vary from the vertical in excess
of [150][_____] mm [6][_____] inches per 30 m 100 feet of depth, the
plumbness of the well shall be corrected by the Contractor at no additional
cost to the Government.
3.2.4.2
Alignment
Alignment shall be tested by lowering into the well a section of cylinder
[3][6][10][15] m [10][20][40] feet long or a dummy of the same length. The
outside diameter of cylinder shall be not more than 13 mm 1/2 inch smaller
SECTION 02525A
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