This paper describes experimental approaches and apparatus that we have developed to study solute and colloid transport in porous media using Idaho National Laboratory's 2-m radius centrifuge. The experimental techniques include water flux scaling with applied acceleration at the top of the column and subatmospheric pressure control at the column base, automation of data collection, and remote experimental control over the internet. These apparatus include a constant displacement piston pump, a

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... custom designed liquid fraction collector based on switching valve technology, and modified moisture monitoring equipment. Successful development of these experimental techniques and equipment is illustrated through application to transport of a conservative tracer through unsaturated sand column, with centrifugal acceleration up to 40 gs. Development of such experimental equipment that can withstand high accelerations enhances the centrifuge technique to conduct highly controlled unsaturated solute/colloid transport experiments and allows in-flight liquid sample collection of the effluent.