A remote dissolution and analytical program for irradiated thorium is given. The aluminum jacket on the slug was dissolved with 6M nitric acid and 0.005M mercuric nitrate. After a water wash, the thorium dissolution was accomplished with concentrated nitric acid made 0.04M in hydrofluoric acid. Weighing, dissolving, and sampling were done remotely in the multicurie cell at the Idaho Chemical Processing Plant. Handling techniques for weighing and dissolving the slugs are described. Transferring and sampling apparatus as well as sampling techniques for the dissolved material are discussed. Analytical data obtained are tabulated. Abstracts of analytical methods for uranium concentration and isotope ratio, aluminum, thorium, cesium, and cerium are given. (auth)

This PITA is designed to permit large-scale application of a change in process water inhibitor concentration before a permanent change to the Water Plant -- Process Standards is fully justified and implemented. Specifically, this PITA authorizes reducing process water dichromate concentration to 1.0 ppm at all reactors (C excluded), provided pH remains at 7.0 {plus_minus} .1.

Methods for dissolving unirradiated uranium-molybdenum alloy reactcr fuels in nitric acid, nitric acid--ferric nitrate, and nitric acid-- phosphoric acid solutions were studied on a laboratory scale. Flowsheets based on the results propose dissolution of alloys containing 3% molybdenum in boiling 6 M HNO/ sub 3/ to yield stsble solutions that are 0.6 M in uranium and 3 to 4 M in nitric acid. The uranium can then be easily decontaminated and recovered in a conventional Purex-type tributyl phosphate solvent extraction process. Alloys containing 10% molybdenum would be dissolved in boiling 11 M HNO/sub 3/, allowing molybdic oxide to precipitate. The molybdic oxide, which carries 5-10% of the uranium, is removed by centrifugation and the acidity of the supernatant solution adjusted tc allow recovery of the uranium by Purex-type solvent extraction procedures. The uranium carried by the molybdic oxide is recovered after the MoO/ sub 3/ is dissolved in warm 5 M NaOH. Less than 0.1% of the uranium is solubilized during the caustic dissolution. Alternative methods investigated involve dissolution in nitric acid containing 0.5 to 1 M ferric nitrate to complex the molybdenum. These techniques lead to undesirably large volumes of high-level solvent extraction waste solutions. Phosphate ion is also …