Beauheim 1987 - Waste Isolation Pilot Plant - U.S. Department of ...

pressure data recorded from downhole transducers
during the pumping and recovery portions of this test
are reported in HydroGeoChem (1985).
The fluid-pressure responses of DOE-1 during the
drawdown and recovery periods were very different.
The shape of the drawdown-data curve on a log-log
plot (Figure 5-76) is indicative of a well intersecting a
single, high-conductivity fracture, with multiple noflow
boundary effects evident at late time. The loglog
plot of the recovery data (Figure 5-77), on the
other hand, shows a clear double-porosity response
with no indications of hydraulic boundaries.
The log-log drawdown plot (Figure 5-76) includes a
simulation generated by INTERPRET for a well
intersected by a single high-conductivity fracture.
The transmissivity of the Culebra apart from the
fracture is 28 ft*/day (Table 5-3) for this simulation.
Assuming a porosity of 20%, a total-system
compressibility of 1 .O x 10-5 psi-‘, and a fluid viscosity
of 1.0 cp, the skin factor for this simulation is -5.1, a
reasonable value for a well intersecting a fracture.
The data match the simulation reasonably well for the
first 13.5 hr, but then, starting with a discrete
pressure drop caused by increasing the pumping
rate from 9.1 to 10.3 gpm (HydroGeoChem, 1985)’
the data deviate above the simulation. This type of
deviation is usually indicative of no-flow (or lower
permeability) hydraulic boundaries. In this case,
multiple boundaries are indicated by the amount of
deviation from the simulation.
102
I I I I
n
ui
5 10’
m
w
K
n
m
m
W
-I
z
0
m
2 100
w
E
n
MATCH PARAMETERS
Ap = 1.0 psi
t
= 1.0 hr
pD = 0.21
tD/CD = 173
CDeZs 7.64 x
n PRESSURE DATA
3i PRESSURE-DERIVATIVE DATA
- SIMULATIONS
%P
*
10-’10c
Y
* I I I I
10’ 102 103 104 105
Figure 5-76. DOE-11Culebra Pumping Test Drawdown Log-Log Plot with INTERPRET Simulation
103