November 2-5

1. Geoscience Horizons November 2-5 upperreservoir sample ceramic plate plate plate with holes base 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 Thequasi-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 Darcy’s 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. Thequasi-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 Darcy’s 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. Geoscience Horizons November 2-5 Methods QSC method The whole apparatus in the bucket of the centrifuge rotor spins in a horizontal position. Thequasi-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 Darcy’s 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. Thequasi-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 Darcy’s 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. Geoscience Horizons November 2-5 water retention hydraulic conductivity Results - lithotype A The two methods give similar results and agree more closely for the hydraulic conductivity.

4. Geoscience Horizons November 2-5 water retention hydraulic conductivity Results – lithotype B The two methods agree well for both the hydraulic conductivity and the water retention.

5. Geoscience Horizons November 2-5 Results – lithotype M water retention hydraulic conductivity The two methods agree well for both the hydraulic conductivity and the water retention.

6. Geoscience Horizons November 2-5 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. Geoscience Horizons November 2-5 Results - water retention curves for all lithotypes • For |h| > 20 cm the water content of lithotype M exceeds that of lithotypes A and B • Differences between A and B are negligible mainly for Wind’s method • The two methods agree well

8. Geoscience Horizons November 2-5 Conclusions about methods • The data show good agreement between Wind’s 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. Geoscience Horizons November 2-5 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