The following report summarizes the work of many investigators in widely varied fields of interest in engineering geology. Detailed documents are referred to in the Plowshare bibliography.

Disposal on a specific retention basic of certain radioactive liquid waste solutions emanating from separations from separations plants has been practiced at Hanford since 1944. As used at Hanford, the term "specific retention" is defined as that volume of waste liquids that may be disposed to the soil* and be held against the force of gravity by the molecular attraction between sand grains and the surface tension of the water, when expressed as percent of packed soil volume. In practice it represents the volume of liquid that may be discharged to a disposal pit of known dimensions without leakage to the ground, water, expressed as percent of the total volume of a column of soil with the same cross section as the pit, and extending from the bottom of the pit to the water table. It is recognized that some degree of lateral spreading will occur which has the effect of enlarging the volume of soil contacted by the liquid.

Basic Studies. It has been reported previously that a reduction of PuO2 to a suboxide does not occur when a powder sample is heated for one hour at 1450 C. To investigate this anomaly, the present hooded facilities were converted from full air flow to an argon atmosphere to prevent oxidation of a possible suboxide. Five grams of PuO2 powder were heated in dry hydrogen to 1500 C for times of one and eight hours. Immediately after discharge, they were mounted and transferred to a helium atmosphere diffractometer hood. The resulting x-ray diffraction pattern consisted only of the single FCC PuO2 phase.

A design and economic analysis is presented for a 44,000 DWT tanker utilizing a 27,300 shp direct cycle boiling water reactor propulsion system. Included are design descriptions and drawings, estimates of operating and capitol costs for the reference ship, estimates of long range potential, descriptions of required research and development programs, a preliminary safeguards analysis, an analysis of ship's motion on boiling water reactor performance, a summary reactor physics analysis, and a discussion of direct cycle accessibility considerations. Also included are summary descriptions for various design alternatives which were considered.