equipment shall be of an approved type and of sufficient capacity to remove
all cutting fluids, sand, rock cuttings, and any other foreign material.
The well shall be thoroughly cleaned from top to bottom before beginning
the well tests. Development shall be performed using only mechanical
surging, over pumping, or jetting, or a combination thereof per ASTM D 5521.
Details of the proposed development method shall be included in the Well
Installation Plan. At the time of development of any well, the well shall
be free of drawdown or surcharge effects due to pump testing, developing or
drilling at another location. The Contractor shall be responsible for
maintaining at the well site the needed access and work area and
clearance, necessary to accomplish development. The Contractor shall
furnish, install, or construct the necessary discharge line and troughs to
conduct and dispose of the discharge [a sufficient distance from the work
areas to prevent damage] [as directed in paragraph CONTAINERIZATION OF
DEVELOPMENT WATER, AND DRILL CUTTINGS]. Development shall be conducted to
achieve a stable well of maximum efficiency and shall be continued until a
satisfactory sand test, as specified in paragraph Sand Test, is obtained.
During predevelopment of the well, filter pack material shall be added to
the annular space around the screen to maintain the top elevation of the
filter pack to the specified elevation. The Contractor shall provide an
open tube or other approved means for accurately determining the water
level in the well under all conditions. If, at any time during the
development process it becomes apparent in the opinion of the Contracting
Officer that the well may be damaged, development operations shall be
immediately terminated. The Contracting Officer may require a change in
method if the method selected does not accomplish the desired results. The
Contracting Officer may order that wells which continue to produce
excessive amounts of fines after development for [6][___] hours be
abandoned, plugged, and backfilled, and may require the Contractor to
construct new wells nearby. All materials pulled into the well by the
development process shall be removed prior to performing the pumping test.
3.4.1
Jetting
Jetting should be performed using either a single or double ring jet. If a
double ring jet is used the rings should be 600 mm 2 feet apart. The
jetting tool shall be constructed of high-strength material and
conservatively designed and proportioned so that it will withstand high
pressures. The jetting tool shall have [two [7][8][10] mm [3/16]
[1/4][3/8] inch diameter hydraulically balanced nozzles spaced 180 degrees]
[four [7][8][10] mm [3/16][1/4][3/8] inch diameter holes spaced 90 degrees]
apart and which shall exert the jetting force horizontally through the
screen slots. The rings shall be constructed such that the tips of the
jets shall be within 13 mm 1/2 inch from the inner surface of the well
screen. The pump used in conjunction with the jetting tool shall be
capable of providing [pressures up to [1700] [_____] kPa [250][_____] psi.]
[a minimum jetting fluid exit velocity of 45 m/s 150 f/s]. Prior to
commencing jetting, and following each jetting cycle, all sand and/or other
materials shall be removed from inside the screen. The jetting process
shall start at the bottom of the screen and consist of rotating the jetting
tool [slowly] [1 cycle per 30 seconds] [[_____] cycles per [_____] seconds]
while rotating the pipe [180][90] degrees for two minutes at each location
then raising the pipe [150][_____] mm [6][_____] inches. All wells, more
than 100 mm 4 inches in diameter, shall be pumped during the jetting cycle
to remove incoming sand and other material. Such pumping shall be at a
rate not less than 115 percent of the rate at which fluid is introduced
through the jetting tool. This will allow a flow of material into the well
as it is being developed. Water used for development shall be free of
sand. The contracting officer may require other means of developing the
SECTION 02521
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