[en] Two main topics are addressed in this report. The first topic relates to the assessment process for shallow land burial site design. This overview includes basic descriptions of water balance, transport processes and technology needs for waste management at an arid (dry) site. The second topic deals with specific results of research activities at PNL related to water and radionuclide transport under arid, shallow land burial conditions. Technology needs at arid-zone (dry) sites are summarized and unique features of radionuclide disposal at dry sites are explained. The report emphasizes the need to understand the interaction between climate, soil, plants, engineered barriers, and buried waste in order to evaluate performance of a waste disposal system at a dry site. Water balance data, collected since FY 1978 at the Buried Waste Test Facility (BWTF) at Hanford, are used to illustrate the influence of climate variables (rainfall distribution patterns and evaporative conditions) on soil water storage and drainage at an arid site. For dry site conditions, with no vegetation and coarse soil, significant deep drainage was measured. Deep drainage below the root zone was also measured at a grass-covered site on the Hanford site after early spring rains, which emphasizes the need to carefully monitor site water balances even at arid (dry) sites. The monitoring technology, water balance, and radionuclide transport at arid sites are discussed, and the use of neutron probes, electrical resistance units, tensiometers, and psychrometers are explained, and examples are given on their applications in arid-site monitoring. Measurements of water flow and radionuclide transport coefficients needed to describe movement in unsaturated soils are documented. 40 references, 21 figures, 5 tables