21 research outputs found
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Characterization of selected waste tanks from the active LLLW system
From September 1989 through January of 1990, there was a major effort to sample and analyze the Active Liquid-Low Level Waste (LLLW) tanks at ORNL which include the Melton Valley Storage Tanks (MVST) and the Bethel Valley Evaporator Service Tanks (BVEST). The purpose of this report is to summarize additional analytical data collected from some of the active waste tanks from November 1993 through February 1996. The analytical data for this report was collected for several unrelated projects which had different data requirements. The overall analyte list was similar for these projects and the level of quality assurance was the same for all work reported. the new data includes isotopic ratios for uranium and plutonium and an evaluation of the denature ratios to address criticality concerns. Also, radionuclides not previously measured in these waste tanks, including 99Tc and 237Np, are provided in this report
Does Solar Physics Provide Constraints to Weakly Interacting Massive Particles?
We investigate whether present data on helioseismology and solar neutrino
fluxes may constrain WIMP--matter interactions in the range of WIMP parameters
under current exploration in WIMP searches. We find that, for a WIMP mass of 30
GeV, once the effect of the presence of WIMPs in the Sun's interior is
maximized, the squared isothermal sound speed is modified, with respect to the
standard solar model, by at most 0.4% at the Sun's center. The maximal effect
on the Boron-8 solar neutrino flux is a reduction of 4.5%. Larger masses lead
to smaller effects. These results imply that present sensitivities in the
measurements of solar properties, though greatly improved in recent years, do
not provide information or constraints on WIMP properties of relevance for dark
matter. Furthermore, we show that, when current bounds from direct WIMP
searches are taken into account, the effect induced by WIMPs with dominant
coherent interactions are drastically reduced as compared to the values quoted
above. The case of neutralinos in the minimal supersymmetric standard model is
also discussed.Comment: 31 pages, 2 tables and 9 figures, typeset with ReVTeX4. The paper may
also be found at http://www.to.infn.it/~fornengo/papers/helio.ps.gz or
through http://www.to.infn.it/astropart/index.htm
Limits to the muon flux from WIMP annihilation in the center of the Earth with the AMANDA detector
A search for nearly vertical up-going muon-neutrinos from neutralino
annihilations in the center of the Earth has been performed with the AMANDA-B10
neutrino detector. The data sample collected in 130.1 days of live-time in
1997, ~10^9 events, has been analyzed for this search. No excess over the
expected atmospheric neutrino background is oberved. An upper limit at 90%
confidence level on the annihilation rate of neutralinos in the center of the
Earth is obtained as a function of the neutralino mass in the range 100
GeV-5000 GeV, as well as the corresponding muon flux limit.Comment: 14 pages, 11 figures. Version accepted for publication in Physical
Review
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Investigation of the organic matter in inactive nuclear tank liquids
Environmental Protection Agency (EPA) methodology for regulatory organics fails to account for the organic matter that is suggested by total organic carbon (TOC) analysis in the Oak Ridge National Laboratory (ORNL) inactive nuclear waste-tank liquids and sludges. Identification and measurement of the total organics are needed to select appropriate waste treatment technologies. An initial investigation was made of the nature of the organics in several waste-tank liquids. This report details the analysis of ORNL wastes
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Determination of small dialkyl organophosphonates at microgram/l concentrations in contaminated groundwaters using multiple extraction membrane disks
Di-isopropyl methylphosphonate (DIMP) and dimethyl methylphosphonate (DMMP) are byproducts and surrogates for Sarin (GB) and VX; they are readily quantitated at {mu}g/L concentrations in groundwaters. Liter aqueous samples are fortified with triethylphosphate, then passed through a sandwich of 3 preconditioned extraction disks: glass fiber filter to remove particulates, C{sub 18}-based extraction disk to collect DIMP, and carbon-based extraction disk to collect DMMP. The two extraction disks are dried and extracted with MeOH. After the extract is fortified with with diethyl ethylphosphonate internal standard, it is analyzed using a gas chromatograph with a nitrogen- phosphorus detector. When the pump and treat criterion is used, detection limits for DMMP and DIMP are 2 {mu}g/L. Method recovery is 40-50%, based on synthetic groundwaters containing 0.2-50 {mu}g/L of each analyte. DIMP and DMMP are cleanly resolved
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Determination of N-nitrosodimethylamine at part-per-trillion levels in drinking waters and contaminated groundwaters
N-nitrosodimethylamine is a high, carcinogenic manufacturing by-product of unsymmetrical dimethyl hydrazine a component of rocket fuel. Prior disposal practices resulted in the contamination of groundwater near certain military installations with both species. The current regulatory threshold promulgated by the US Environmental Protection Agency (EPA) for NDMA in surface waters designated for drinking is 0.7 ng NDMA/L (0.7 pptr)L. Existing procedures for determining NDMA in aqueous samples typically employ dichloromethane extraction followed by concentration to a final volume of 1 mL, and gas chromatographic analysis of a 2 {mu}L aliquot of concentrate using either a nitrogen-phosphorus detector (NPD), mass spectrometric detector, or chemiluminescent nitrogen detector (CLND). Such a protocol does not permit detection of NDMA at the desired health-based criterion unless high-resolution mass spectrometric (HRMS) detectors are employed. The analytical procedure described in this work employed an initial solid-phase extraction of groundwater samples with a preconditioned Empore C{sub 18} disk, used to remove interfering neutral species including di-isopropylmethane phosphonate (DIMP), prior to continuous overnight extraction
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The Hydrolysis of Di-Isopropyl Methylphosphonate in Ground Water
Di-isopropyl methylphosphonate (DIMP) is a byproduct from the manufacture of the nerve agent Sarin. The persistence of DIMP in the ground water is an important question in evaluating the potential environmental impacts of DIMP contamination. The half-life of DIMP in ground water at 10 deg C was estimated to be 500 years with a 95% confidence interval of 447 to 559 years from measurements of the hydrolysis rates at temperatures between 70 to 98 deg C.Extrapolation of the kinetics to 10 deg C used the Arrhenius equation, and calculation of the half-life assumed first-order kinetics. Inorganic phosphate was not detected
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Sampling and analysis of inactive radioactive waste tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14 at ORNL
The sampling and analysis of nine inactive liquid low-level waste (LLLW) tanks at the Oak Ridge National Laboratory (ORNL) are described-tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14. Samples of the waste tank liquids and sludges were analyzed to determine (1) the major chemical constituents, (2) the principal radionuclides, (3) metals listed on the US Environmental Protection Agency (EPA) Contract Laboratory Program Inorganic Target Analyte List, (4) organic compounds, and (5) some physical properties. The organic chemical characterization consisted of determinations of the EPA Contract Laboratory Program Target Compound List volatile and semivolatile compounds, pesticides, and polychlorinated biphenyis (PCBs). This report provides data (1) to meet requirements under the Federal Facility Agreement (FFA) for the Oak Ridge Reservation to characterize the contents of LLLW tanks which have been removed from service and (2) to support planning for the treatment and disposal of the wastes
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Characterization of explosives processing waste decomposition due to composting. Final report
The objective of this work was to provide data and methodology assisting the transfer and acceptance of composting technology for the remediation of explosives-contaminated soils and sediments. Issues and activities addressed included: (a) chemical and toxicological characterization of compost samples from new field composting experiments, and the environmental availability of composting efficiency by isolation of bacterial consortia and natural surfactants from highly efficient composts, and (c) improved assessment of compost product suitability for land application