The aqueous biphasic extraction (ABE) process for soil decontamination involves the selective partitioning of solutes and fine particulates between two immiscible aqueous phases. The biphase system is generated by the appropriate combination of a water-soluble polymer (e.g., polyethylene glycol) with an inorganic salt (e.g., sodium carbonate). Selective partitioning results in 99 to 99.5% of the soil being recovered in the cleaned-soil fraction, while only 0.5 to 1% is recovered in the contaminant concentrate. The ABE process is best suited to the recovery of ultrafine, refractory material from the silt and clay fractions of soils. During continuous countercurrent extraction tests with soil samples from the Fernald Environmental Management Project site (Fernald, OH), particulate thorium was extracted and concentrated between 6- and 16-fold, while the uranium concentration was reduced from about 500 mg/kg to about 77 mg/kg. Carbonate leaching alone was able to reduce the uranium concentration only to 146 mg/kg. Preliminary estimates for treatment costs are approximately $160 per ton of dry soil. A detailed flowsheet of the ABE process is provided.

The following report follows a geochemical survey and its findings in the Valdez quadrangle in south-central Alaska.

A report that provides examples of 1990's sonar advances that help map the sea floor. Two specific devices are focused on, these are the Sea Beam bathymetric mapping system and the GLORIA sidescan-sonar imaging system.

A report which provides an overview of eruptions from Mount Spurr and the Alaska Volcano Observatory's response to them.

A report about nomenclature related to planets in the solar system. It contains detailed information about all names of topographic and albedo features on planets and satellites.