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

I
,EQUILIBRATION
BUILDUP
Elapsed Time in hours
Stan Date 08/05 87
SIanTlme OOOOW
Linear-Linear Sequence Plot
H-16 DST 677-690iTAMAUIS.K CLAYSTONE
Figure 5-83. H-1 6/Tamarisk Claystone Shut-In Test Linear-Linear Sequence Plot
least-transmissive unit successfully tested in H-16,
the unnamed lower member siltstone (2 x
10-4 ftz/day; Table 5-2).
5.2.4 Magenta Dolomite Member. The Magenta
dolomite was tested in wells H-14 and H-16. The
objectives of the Magenta testing were to obtain
quantitative information on the hydraulic head and
transmissivity of the unit.
5.2.4.1 H-14. At H-14, the Magenta lies from
423.8 to 447.5 ft deep (Figure 3-6). The Magenta was
tested in a DST straddle interval from 420.0 to
448.5 ft deep, which included 4.8 ft of overlying and
underlying gypsum. This gypsum is not thought to
have contributed significantly to the responses
observed during testing. The Magenta was tested
from October 10 to 13, 1986. Drillstem testing
consisted of three flow periods and three buildup
periods (Figure 5-84). Descriptions of the test
instrumentation and the test data are contained in
Stensrud et al. (1987).
To obtain equivalent constant-rate flow periods, each
of the three flow periods was subdivided into two
shorter periods. The FFL, which lasted about 15
minutes, was divided into two periods with flow rates
of 0.049 and 0.014 gpm (Table 5-1). The SFL, which
lasted about 30 minutes, was divided into two
periods with flow rates of 0.036 and 0.010 gpm.
Finally, the TFL, which lasted about 60 minutes, was
divided into shorter periods with flow rates of 0.014
and 0.007 gprn. The durations of the buildup periods
were approximately 18.5, 23.5, and 21.1 hr for the
FBU, SBU, and TBU, respectively.
As can be seen first on the linear-linear sequence
plot of the Magenta DST's (Figure 5-84), the
presence of an overpressure skin had a significant
effect on the observed buildup responses. When the
Magenta interval was initially shut in for an
equilibration period following swabbing, the fluid
pressure rose to a peak of 134.2 psia and then
gradually declined. Six hours into the FBU, the
pressure peaked at 123.2 psia, and then declined for
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