The preceding report follows an extensive study made at Hanford of methods and equipment to remove effectively the dissolver vent gases.

Report summarizing data from Purex tests for pulse column specifications. These test results were used to estimate pilot plant specifications.

The following report provides data collected during an investigation in the Columbia River. The purpose of this investigation was to research the radioactivity present in the bottom-living organisms of the river.

Abstract: "This is the preliminary report of a radiological-ecological survey of the invertebrate fauna that inhabit the Columbia River within the confines of Hanford Works and downstream to the site of McNary Dam. The survey was carried out during the period of October, 1948 through February, 1950. Materials and methods are discussed and the results of extensive radioassays, qualitative and quantitative biological determinations, and hydrographic studies are given and analyzed. Twelve figures and twenty-three tables are included. All aquatic invertebrates were found to be concentrating radioactivity from the river water. A maximum activity density of 4.4-10-(-3) μc/g wet weight was found in the larvae of midges (Hydrobaeninae) collected near Hanford during September, 1949. Radioactive wastes were not found to be causing any apparent deleterious effects to the natural invertebrate fauna. Existing population variations are caused by biological and hydrographic conditions."

This report follows an investigation of a cargo truck found contaminated by various radioactive material on a routine trip from Arco, Idaho to the Hanford plant on May 8, 1952. The report analyzes the truck's route in an attempt to find the location of the contaminating region.

Abstract: The data obtained from the radioassay of fish collected in vicinity of the Hanford Works between April, 1948 and June, 1950 are presented. Most of the radioactivity in the fish resulted from the concentration of p32 in the scales, bone, and certain visceral organs. The level of activity density in the fish was influenced by size, feeding habits and metabolic rate in addition to the activity density of the water. Changes in operation of nuclear reactors have resulted in progressive increases in activity densities of fish from one year to the next. The levels of radioactivity are not sufficiently high to be hazardous to either the fish or persons eating them.