The scope of the decommissioning work provides for (1) the removal of all Division of Military Application (DH) fabrication and inspection equipment held in standby status in the 234-5Z Building, (2) disposition of all contaminated equipment and materials removed by packaging for 20-year retrievable storage, (3) reclamation of salvageable materials and equipment for use on site by other Energy Research and Development Administration contractors, and (4) restoration of cleared-out areas for other future Richland Operations Office programs.

Decommissioning of the DMA facilities is estimated at 65% complete compared to 60% forecast at the start of the program in April 1974. The transfer of 12 transuranic boxes to 20-year retrievable storage this quarter brings the total to date to 26, and includes all of the inspection area glove boxes and conveyor sections, four A-Line and two C-Line glove boxes, along with all auxiliary hydraulic equipment pumps, and piping serving the three areas. Removal of additional A-Line and C-Line conveyor sections, one glove box, and relocation of two other glove boxes has been authorized by the Energy Research and Development Administration. Albuquerque Operations Office, and the A-Line portion of work currently is estimated at 40% complete. The removal of the one high plutonium-containing glove box, HC-40D and B has been delayed for additional sodium iodide (NaI) gamma counting following Z-Plant Operations cleanout and recovery of over 1,900 grams of plutonium. The fiscal year 1975 cost was $1,080,000 as estimated, and includes $11,585 in accrued costs for Fiberglass Reinforced Polyester (FRP) plywood boxes delivered but not billed at month-end. Thirty-eight of the 51 FRP boxes on order have been delivered to date, and the cost of $98,767 is included in …

BeO ceramic disks were evaluated for application as dosimeters for both penetrating and non-penetrating radiation. Response to penetrating radiation was measured as thermoluminescence (TL) and to non-penetrating radiation as thermally stimulated exoelectron emission (TSEE). Field experiments demonstrated that both TSEE and TL responses from BeO can monitor diverse radiation fields. BeO disks in a passive dosimeter were found to be sensitive to a lower exposure level of 100 pCi-day/liter of radon. The depth of the more active exoelectron layer in BeO was found to be 4 ..mu..m. A second less active, exoelectron layer extends to a depth of at least 16 ..mu..m.

To supply the heat input required by space-borne Vuilleumier refrigerators, a possible design for a reliable Pu-238 radioisotope heat source, based on state-of-the-art technology, is described. The isotope heat source would replace electrical heaters powered by solar panels and batteries, and would be adaptable to existing VM refrigerators without redesign. The heat source contains all necessary safety features, and also a simple thermal control system to permit refrigerator shut-down for indefinite duration. A system for thermal interfacing with the spacecraft, the booster, and ground support is also described. The isotope heaters are compared with solar-electric heaters for the same application, and found to result in very significant weight and size savings.

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During the heat treatment step of High Temperature Gas-Cooled Reactor (HTGR) fuel beads, the /sup 233/U-loaded fuel beads are exposed to temperatures as high as 1700/sup 0/C. Since /sup 233/U fuel beads unavoidably contain a small percentage of /sup 232/U, decay products of /sup 232/U might be released during the heat treatment step. To avoid shielding requirements, experiments were conducted using /sup 232/Th-loaded fuel beads rather than /sup 232/U-loaded fuel beads. Decay products of /sup 232/U and /sup 232/Th are the same after /sup 228/Th. Experimental data were obtained by monitoring the 583 and 2614 keV gamma emissions of /sup 208/Tl. Computer simulations of the decay process and experimental data were used to infer what relative amount of the daughter products was removed. The carbonization step (300 to 500/sup 0/C) has an effect on the loss of daughter products in the conversion step. Using uncarbonized fuel beads, approximately 50 percent of /sup 220/Rn was removed at 300/sup 0/C and approximately 20 percent of /sup 220/Rn was removed at 200/sup 0/C. At most, 5 percent of /sup 220/Rn was removed from uncarbonized beads at 25/sup 0/C. Marginal /sup 220/Rn loss was detected at 100/sup 0/C using pre-carbonized beads. At 1400/sup 0/C, …

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Albedo neutron dosimeters have proven to be effective as a method of measuring the dose from low-energy neutrons that other types of personnel neutron dosimeters do not detect. Many albedo neutron dosimeters have been designed, and some are being used extensively. All albedo neutron dosimeters are energy- dependent, becoming less sensitive as the energy of the neutrons is increased. In this paper the energy dependence and the effect it has on the evaluation of the dose are discussed. Numerous measurements are shown which were made under field conditions at five reactors, two accelerators, a radiochemistry facility, two plutonium facilities, a low-scatter neutron irradiation facility, three storage vaults, and at the N.B.S. low-energy neutron beams. These measurements show the limits imposed by the energy dependence on the evaluation of the dose determined by albedo neutron dosimeters. In most cases evaluation of an individual's dose occurring in a single facility can be reasonably accurate, but it must be known in which facility the person was exposed. Procedures using the incident thermal neutron response of TLDs located on top of the dosimeter to correct for the energy dependence are discussed; and errors caused by wearing a dosimeter improperly are evaluated. (auth)

Thermoluminescence dosimetry is the principal means of measuring ambient $gamma$ radiation at the Lawrence Livermore Laboratory. These dosimeters are used at 12 perimeter locations and 41 locations in the off-site vicinity of the Laboratory, and are exchanged quarterly. Control dosimeters are stored in a 75- mm-thick lead shield located out-of-doors to duplicate temperature cycling of field dosimeters. Effect of dosimeter response to radiation in the shield is determined each quarter. Calibration irradiations are made midway through the exposure cycle to compensate for signal fading. Terrestrial exposure rates calculated from the activities of naturally occurring uranium, thorium, and potassium in Livermore Valley soils vary from 3 to 7 $mu$R/hr. Local inferred exposure rates from cosmic radiation are approximately 4 $mu$R/hr. TLD measurements are in good agreement with these data. Off-site and site perimeter data are compared, and differences related to Laboratory operations are discussed. (auth)

The characteristics of diffraction dissociation of neutrons into p$pi$$sup -$ systems at high energies were examined. A substantial correlation is observed between the mass and the t of the produced system. The spin structure of the p$pi$$sup -$ amplitudes at low mass is very complex, but is described surprisingly well by the simple Deck Mechanism. Both $pi$-exchange and proton-exchange contributions are evident in diffractive production. The t- channel and s-channel helicity amplitudes contain comparable contributions from flip and nonflip terms and the produced states are not restricted to those expected on the basis of the Morrison rule. (auth)

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A radiological survey of Bikini and Eneu Islands of the Bikini Atoll was conducted during June 1975 to assess the potential radiation doses that may be received by the returning Bikinians. Bikini Atoll was one of the U.S. nuclear weapons testing sites in the Pacific. An integral part of the survey included measurements of the gamma-ray exposure rates at 1 m above the ground with portable NaI instruments at nearly 2700 locations on the two islands. For comparison purposes, similar measurements were made with a pressurized ion chamber at approximately 200 locations, and with LiF and CaF$sub 2$:Dy thermoluminescent dosimeters (TLDs) at 80 locations. The results indicate that the NaI scintillators overresponded because of their nonlinear energy characteristics. The responses of the LiF dosimeters and the pressurized ion chamber agreed to within 13 percent. Attenuation studies with LiF TLDs indicated that roughly 25 percent of the total free air exposure rate at 1 m was due to beta radiation. (auth)