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1
Methods
QSC method The apparatus includes a
flow-controlling reservoir above the sample,
filled with water at the start of each run. The
reservoir bottom is made from a thin, flexible
material, which supports a cake of fine granular
material that controls the flow rate into the
sample.

ceramic plate
The quasi-steady centrifuge (QSC) method The
steady-state centrifuge (SSC) method, which the
QSC method derives from has a steady flow of
water within a sample in a centrifuge, applied by
either a constant head (Nimmo et al., 1987) or a
metering pump (Conca and Wright, 1998). If
suitable conditions develop within the sample,
K(q) can be computed using the centrifugal form
of Darcys law. The QSC method somewhat relaxes
the criterion for steadiness. This entails a
slight increase in measurement uncertainty, but
affords advantages including simpler apparatus,
larger sample capacity, and adaptability to
various machines and operating conditions.
The quasi-steady centrifuge (QSC) method The
steady-state centrifuge (SSC) method, which the
QSC method derives from has a steady flow of
water within a sample in a centrifuge, applied by
either a constant head (Nimmo et al., 1987) or a
metering pump (Conca and Wright, 1998). If
suitable conditions develop within the sample,
K(q) can be computed using the centrifugal form
of Darcys law. The QSC method somewhat relaxes
the criterion for steadiness. This entails a
slight increase in measurement uncertainty, but
affords advantages including simpler apparatus,
larger sample capacity, and adaptability to
various machines and operating conditions.
2
Methods
QSC method
The whole apparatus in the bucket of the
centrifuge rotor spins in a horizontal position.
The quasi-steady centrifuge (QSC) method The
steady-state centrifuge (SSC) method, which the
QSC method derives from has a steady flow of
water within a sample in a centrifuge, applied by
either a constant head (Nimmo et al., 1987) or a
metering pump (Conca and Wright, 1998). If
suitable conditions develop within the sample,
K(q) can be computed using the centrifugal form
of Darcys law. The QSC method somewhat relaxes
the criterion for steadiness. This entails a
slight increase in measurement uncertainty, but
affords advantages including simpler apparatus,
larger sample capacity, and adaptability to
various machines and operating conditions.
The quasi-steady centrifuge (QSC) method The
steady-state centrifuge (SSC) method, which the
QSC method derives from has a steady flow of
water within a sample in a centrifuge, applied by
either a constant head (Nimmo et al., 1987) or a
metering pump (Conca and Wright, 1998). If
suitable conditions develop within the sample,
K(q) can be computed using the centrifugal form
of Darcys law. The QSC method somewhat relaxes
the criterion for steadiness. This entails a
slight increase in measurement uncertainty, but
affords advantages including simpler apparatus,
larger sample capacity, and adaptability to
various machines and operating conditions.
3
Results - lithotype A
The two methods give similar results and agree
more closely for the hydraulic conductivity.
4
Results lithotype B
The two methods agree well for both the hydraulic
conductivity and the water retention.
5
Results lithotype M
water retention
hydraulic conductivity
The two methods agree well for both the hydraulic
conductivity and the water retention.
6
Results - hydraulic conductivity for all
lithotypes

• Lithotypes A and B have greater hydraulic
  conductivity than lithotype M
• Slopes of the K(q) curves are similar
• The difference in K(q) for the same lithotype
  may be due to slight variations within the
  samples
• The QSC method extends to lower values of K

7
Results - water retention curves for all
lithotypes

• For h gt 20 cm the water content of lithotype M
  exceeds that of lithotypes A and B
• Differences between A and B are negligible mainly
  for Winds method
• The two methods agree well

8
Conclusions about methods

• The data show good agreement between Winds
  method and the new Quasi-Steady Centrifuge (QSC)
  method
• Minor differences in the results may be caused by
  differences among the samples such as relative
  amounts of matrix, fossils and cement
• The agreement between the hydraulic conductivity
  values obtained with the different methods is
  important because hydraulic conductivity is
  difficult to measure and few methodologies
  currently exist
• The QSC method extends to lower values of
  hydraulic conductivity
• The QSC method shows promise for further
  measurements on calcarenite and possible
  widespread application

9
Conclusions about Calcarenite

• The hydraulic behavior of the analyzed rocks is
  very similar near saturation while it differs for
  unsaturated conditions
• This implies the need for further measurements of
  unsaturated hydraulic properties
• Accurate measurements of unsaturated hydraulic
  properties are important for quantitative
  interpretation of the behavior of water within
  the vadose zone as related to contaminant
  transport and water supply