TM 5-818-5/AFM 88-5. Chap 6/NAVFAC P-418
(Courtesy of UOP Johnson Division)
Figure C-7. Drawdown versus distance from test well.
C-4. Nonequilibrium pumping test.
flow can be expressed as
H-h =
(C-3)
a. Constant discharge tests. The coefficients of
T'
transmissibility T, permeability k, and storage S of a
where
homogeneous, isotropic aquifier of infinite extent with
H - h = drawdown at observation peizometer, feet
no recharge can be determined from a nonequilibrium
well discharge, gallons per minute
type of pumping test. Average values of S and T in the
W(u) = exponential integral termed a "well func-
vicinity of a well can be obtained by measuring the
tion" (see table C- 1)
drawdown with time in one or more piezometers while
T' = coefficient of transmissibility, gallons per
pumping the well at a known constant rate and analyz-
day per foot width
ing the data according to methods described in (1), (2),
and
and (3) below.
1.87r2S
u=
(C-4)
T't'
(1) Method 1. The formula for nonequilibrium
C-7
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