Well-type scintillation counters have found use in many radiochemical laboratories. A gamma scintillation well counter has been used to measure the gamma activity of liquid samples in the 325 Building counting room for about a year. This well counter has been built and calibrated so that gamma activity measurements made with it can be easily compared with measurements made with the gamma scintillation counter (GSC). The well counter is electronically identical to the present GSC and differs only in the shape of the crystal used and the physical arrangement of the lead shield. The crystal contains a well which allows a tube containing the sample to be inserted in the crystal. The physical arrangement of the detector greatly simplifies the preparation of liquid samples for activity measurement. The 325 Building well counter and its application to chemical research and plant process analysis will be discussed in the following paragraphs. An operating procedure is also included.

A preliminary soil column experiment with a waste sample from the 207-S-11 well, which monitors the 216-S cribs, indicated that cesium was absorbed almost completely by the soil but that strontium breakthrough to ground water in the near future seemed likely. Accordingly, it was suggested that the 216-S wastes be discharged to a new disposal site, and that samples of the wastes which are currently being discharged to the 216-S cribs be obtained for soil absorption tests. The primary purpose of these tests was to obtain data which could be used to suggest ways and means of improving the absorption of strontium by soil from the process condensate stream (D-2_ and the cell drainage stream (D-1), both of which have been discharged to the 216-S cribs for the past several months.

The primary purpose of this writeup is to present a description of the electrical and mechanical features of the developed system for use in maintenance and operation of a simultaneous scaler control unit.

The absorption of the important fission products by plants is quantitatively presented as a concentration factor which is defined as the ratio of the fission product concentration found in the leaves to the fission product concentration found in the nutrient substrate. Of the fission products, the isotopes of strontium were found to be the most important by virtue of their high concentration factor, long half-life, and low maximum permissible amounts for animals. Iodine and barium follow in importance, with cesium moderately important in some soils. All other fission products have concentration factors less than strontium by 100 or more. The effect on the concentration factor of different agricultural plants, as well as different organs of the same plant, causes variations of about a factor of ten or less for each isotope. The concentration factor tends to increase as the pH of the nutrient substrate is decreased. Addition of stable carrier to the substrate does not decrease the amount of the radioactive isotope that is absorbed into the plant. The presence of iodine and yttrium carrier actually causes a significant increase in the concentration of the respective radioactive isotopes in the plant tissue.

A perspective drawing of typical hood cells arranged in series for an assembly line operation is presented. Advantages of this improved enclosure for low level radiation work are listed which recommend its use on new facilities in preference to more conventional designs.

Ultrasonic testing has been investigated as a possible non-destructive method for checking the bond integrity of certain type fuel elements. Equipment has been developed to inspect experimental fuel elements for various research programs. Circuits have been devised to discriminate the size of defects and to map the areas which are unbonded.

The information in this report is based on experience with a similar unit installed on experimental pule columns in the 321 Building. These installations were made to demonstrate the feasibility of the system. In one case, the installation on the 2A Prototype Column, the differential pressure cell (D/P cell) bottom interface control system was monitored by a capacitance-type instrument. The other installations were made on glass columns and were monitored visually.

In the Columbia River downstream from Richland, Washington there is a gradual decrease in concentration of radioactive isotope. At any one location there are fluctuations due to factors such as dilution and decay time. During this period at all locations the concentration of alpha particle emitters in water averaged below the detection limit. Beta particle emitters in water upstream of McNary Dam decreased slightly due to increased river flow this quarter, with averages at various locations. Downstream from McNary Dam, beta particle emitter average concentrations in water were about the same as the past three quarters.

During this quarter, the Hanford Atomic Products Operation reorganized with the elimination of the Radiological Sciences Department as a separate organizational entity. The new structure which was effective on September 1, 1956, is outlined in this report to indicate the new relationships.

There is a continuing high interest in the development of organic coolant technology for application to future Hanford reactors. In addition to the HAPO organic program, two other programs are being sponsored by the Atomic Energy Commission. These include the Naval Reactor program, aimed at a reactor for ship propulsion, and the Civilian Power Reactor program. Because of the similarity of the technical efforts in the three programs, an attempt is being made to establish effective liaison among the programs. To this end, a visit was made to several sites actively engaged in organic development work. These sites and their primary functions are detailed in this report.

Transfer operations of highly radioactive solutions by the normal transfer pipette leads in most instances to a spread of contamination in the shielded facility. In the dripless pipette, the solution is held in the reservoir by the use of the siphon principle.

In the fall of 1952, a pilot plant batch dissolution study was carried out to obtain the data required for the design of the Purex Plant dissolvers. Particular emphasis was placed on the rate of dissolution and the efficiency of nitrogen oxide recovery from the dissolver off-gas. The results are presented in this report.

Cluster fuel elements meet many of the requirements of high temperature recirculating water reactors and have several advantages over solid fuel elements. Operation at higher specific power levels for a given temperature limit are attainable because of the larger heat transfer surface. Failure of a single rod in cluster does not restrict coolant flow as severely as failure of a solid fuel element, hence the number and severity of stuck charges can be reduced.

Under the general heading of Reactor Lattices are reported a new method of calculating resonance escape probabilities, results for the effective mass of a proton bound in the water molecule, and a comparison of similar techniques for calculating lattice constants developed independently by Hanford physicists and by a school of Russian physicists (as reported at the Geneva Conference). An estimate of maximum errors in f and η for thermal systems is described. Experiments and analysis thereof on the effects of neutron streaming in air channels through a moderator are reported. Buckling calculations and experimental results are given for graphite lattices employing 1.17-inch diameter natural uranium slugs and U²³⁵-Aluminum alloy slugs. An experimental measurement of the critical mass of an annular cylindrical array is described. Some measurements on, and the status of, construction of the Lattice Testing Reactor are reported. Under Instrumentation, development of a BF/sub 3/ counter suitable for operation at elevated temperatures is described. Some measurements on, and the status of, construction of the Lattice Testing Reactor are reported. Under Instrumentation, development of a BF₃ counter suitable for operation at elevated temperatures is described. A method of determining the screening parameter in the Thomas-Fermi model of the atom is …