This report analyzes Parian and Teflon that were exposed to solutions of 1AX, 1AS, and 1AF, ANL June 1, 1948 Flowsheet, under conditions described in the following report.

Objective: "The laboratory equilibrium study RC-E-1 described in this report was carried out to obtain uranium equilibrium curves at various concentrations of nitric acid and of TBP."

From introduction: "This report is concerned with exploratory experiments designed to studies the efficiency of a number of scavengers for zirconium and niobium adsorption and to provide preliminary information on the best conditions to employ on the most satisfactory of those scavengers studied, namely Super Filtrol FO. The data in this report include data obtained through October, 1949, and are by no means considered to be final. The investigation is currently being actively continued."

The following report provides results from laboratory tests on the corrosion resistance of various types of stellite facings on astenitic stainless steel T-347 to Redox streams.

Report summarizing physical studies on Redox solutions and metal waste solutions, including refractometric investigations.

Report discussing study on recovery of nitric acid in the uranium recovery process. The behavior of chloride ions and tributyl phophate is noted, and the quality of recycled nitric acid was tested. Stainless steel in the nitric acid recovery system was evaluated for corrosion.

The following report describes a chemical procedure to analyze fission products and long-lived rare earths in both untreated urine samples and the supernates from the precipitation steps in the TTA procedure for plutonium.

Introduction: "A limited test progress for the evaluation of type 347 stainless steel pipe which failed the Huey (?) test has been complicated. The tests reported herein were similar in scope to those reported in document number EW-20765, Corrosion Tests on Stainless Steel Plate, Waste Metal Recovery Process. Material tested was obtained on order number EWC-8553, National Tube Company Heat #3X9741. Lots 9789 and 9790."

Report discussing the details of a radiation burst in a spherical reactor using plutonium nitrate fuel that occurred on November 16, 1951 at Hanford Works.

This report discusses a proposed method for treating the effect of increasing critical mass of plutonium solutions, which occurs when hydrogen density is reduced by dilution with heavier nuclei.

Two xenon extraction runs were made this month. It appears that a small design change in Trap #2 will be necessary so that a dry ice-trichloroethylene slurry can be used for coolant rather than liquid freon. For each of the runs this month the enriched generator was exposed for four hours in the est pile operating at 100 watts. A period of eight hours for cooling and xenon builidup was allowed before the collection and separation runs were started.

Hanford uranium contains minute angular inclusions which affect the microstructure, reactivity, and other important factors controlling the serviceability of the metal. Small quantities of the inclusions have been isolated by chemical means, and the x-ray diffraction patterns and chemical analyses of the isolated materials have been determined. As a first step in the identification of the inclusions present in rolled uranium, a search was made for a chemical method of separating the inclusions from the matrix metal.

During the canning of slugs for Production Test 313-105-3-M, a high number of rejects were caused by gas voids in the A1-S1 bonding layer. Since the heat treatment of the slugs in a molten salt bath resulted in a chemically altered surface, an investigation was made to determine the volume of gas evolved from salt-bath heat-treated slugs as compared to other types of slugs. This test was designed as a preliminary test to determine if there were a significant differences.

The remodeling, fabrication, and instrumentation of a high vacuum system are described. The faults encountered with the old system and their solution are outlined. Tests were made on diffusion pump oils and on the reduction of pump oil back diffusion. The measurement of high vacuum pressures by a cold cathode ionization gage at various points on a vacuum system are discussed.

Abstract: "A titrimetric method for the determination of fluoride in plutonium is reported. Prior to a steam distillation of the fluoride, the bulk of the plutonium is separated by precipitation of the sulfate. The fluoride in the distillate is titrated at a pH of 3.2 with 0.001 M thorium nitrate, using chrome azurol-S indicator. Applied to samples containing 1 to 15 parts per million fluoride, the recovery is 87% and the precision on the 95% confidence level is +/- 0.65 ppm."

The purpose of this report is to present the information obtained relative to the characteristic adsorption of radioisotopes in a long (forty feet) laboratory soil column treated with a high salt, process waste of high activity density. The movement of adsorbed cations in a soil column subjected to prolonged leeching by water also was determined.

Two methods for calculating the *reduction in η due to spectral hardening have been used. In the first method it is assumed that the absorption cross section of U-238 is l/v. This indicates no change in η within the error of the calculation. In the second it is assumed that the scattering cross section of uranium is constant. A decrease in η of 3.0% at the centerline of the slug is indicated by this calculation. The assumption U-238 is a l/v absorber is regarded as the most reasonable of the two.

The erection of a concrete biological shield at Hanford, Washington presented several unique construction problems. This shield encloses the radioactive core of a reactor and is designed to protect operating personnel from the harmful effects of pile neutrons and associated gamma radiation. Permanent steel forms were erected to close tolerance around the reactor and filled with high density concrete by means of prepacked method. Prefabricated sections of the steel forms, or crates, were five to eight feet deep and weighed up to 18 tons each. During erection, the process holes through successive crates were kept within 0.012 in. of their nominal distance. The left side, top shield, and right side of this biological shield were constructed integrally to form a rigid frame. The front and rear crates, which contain numerous process holes, were keyed into the side and top shields so as to permit relative expansions of shield components and to provide for their lateral support. These massive steel and concrete walls provide considerable resistance to blast and earthquake forces, support numerous process facilities, contain pile gas, as well as protect personnel from nuclear radiation.

A knowledge of the mechanical and physical properties of uranium is important in understanding and explaining its pile behavior. The effects of irradiation on the properties of uranium will be dealt with in another chapter. However, it is important to know and understand the pre-irradiation properties of uranium prior to investigating the effects of irradiation.

This report describes the evaluation of physical properties of AGHT and 185-W graphites that are important to pile construction and operation. On the basis of these data, purified AGHT graphite was allocated to either filler block positions in the central regions of the K piles or to the upper or lower reflectors. This decision was based on the similarities of physical properties between AGHT graphite and the other moderator components. A similar allocation could be made for 185-W graphite for some future pile if it can be successfully purified or if purification is not required.

A large (size 2) Purex pulse generator was installed in the 321 Building Tan Farm to pulse solutions in the prototype Purex HA Column. Flow sheet considerations indicated a need for information on leakage rates with various size weep holes in the pulse generator piston. In addition to leakage tests, experiments were conducted to determine the air required under the piston to hold the column contents away from the pulse generator piston thereby preventing leakage during shut down and the determine the time required to bleed the air trapped in the pulse leg when the column is first filled. [...] Leakage past the piston was not appreciably affected by pulse frequency. [..] Bleeding the air out of the pulse leg under start-up conditions, even with the piston weep hole plugged, was rapid. The longest time required to bleed the pulse leg was 36 minutes, which included a column-filling time of 30 minutes.

This report is a survey of methods for determining trace amounts of nitric oxide and nitrogen dioxide in air. The methods are evaluated in relation to their applicability to continuous monitoring procedures for these substances in stack gas and in air for human consumption.

The purpose of this paper is to examine the theory and results of chemical exchange experiments for separation of heavy metal isotopes. The aim is to find a means of predicting those chemical exchange systems likely to produce large isotopic separation factors.

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.