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Sample records for lysimeter investigations low-level

  1. BNFL Lysimeter programme to investigate the leaching of radionuclides from low-level radioactive waste

    SciTech Connect

    Clayton, K.; Clegg, R.; Holmes, R.G.G.; Newton, G.W.A.

    1993-12-31

    British Nuclear Fuels plc has initiated an experimental programme to measure the leaching behavior of radionuclides from various low level radioactive waste (LLW) materials using Lysimeters. The programme commenced in 1986 and to date 10 lysimeters have been commissioned. These have concentrated on simulating shallow trench conditions but a further programme is now planned to study concrete vault environments. The aim of the study is to provide information on leaching processes as part of the ongoing Drigg Near Field Programme, and also to yield input data for radiological assessment purposes. Towards this end, data have been gained from the lysimeters on basic chemistry, gas generation and radionuclide Release Coefficients. This paper concentrates on one of the lysimeters which has recently been decommissioned and for which interim analytical data are available. Some general comments are given on BNFL`s experience using lysimeters and their applicability as a rapid and effective technique for studying near field degradation processes.

  2. Field Lysimeter Investigations: Low-Level Waste Data Base Development Program for fiscal year 1994. Annual report, Volume 7

    SciTech Connect

    McConnell, J.W. Jr.; Rogers, R.D.; Jastrow, J.D.; Sanford, W.E.; Sullivan, T.M.

    1995-05-01

    The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the US Nuclear Regulatory Commission, is (a) studying the degradation effects in EPICOR-II organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified EPICOR-II resins, (c) obtaining performance information on solidified EPICOR-II ion-exchange resins in a disposal environment, and (d) determining the condition of EPICOR-II liners. Compressive test results of 11-year-old cement and vinyl ester-styrene solidified waste forms are presented, which show effects of aging and self-irradiation. Results of the ninth year of data acquisition from the field testing are presented and discussed. During the continuing field testing, both portland type I-II cement and Dow vinyl ester-styrene waste forms are being tested in lysimeter arrays located at Argonne National Laboratory-East in Illinois and at Oak Ridge National Laboratory. The study is designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over a 20-year period.

  3. Field lysimeter investigations: Low-level waste data base development program for fiscal year 1996. Annual report; Volume 9

    SciTech Connect

    McConnell, J.W. Jr.; Rogers, R.D.; Larsen, I.L.; Jastrow, J.D.; Sanford, W.E.; Sullivan, T.M.; Fuhrmann, M.

    1997-08-01

    A data base development program, funded by the US Nuclear Regulatory Commission, is (a) studying the degradation effects in organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified ion-exchange resins, (c) obtaining performance information on solidified ion-exchange resins in a disposal environment, and (d) determining the condition of liners used to dispose the ion-exchange resins. During the field testing experiments, both portland type 1--2 cement and Dow vinyl ester-styrene waste form samples were tested in lysimeter arrays located at Argonne National Laboratory-East (ANL-E) in Illinois and at Oak Ridge National Laboratory (ORNL). The study was designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over an extended period. Those experiments have been shut down and are to be exhumed. This report discusses the plans for removal, sampling, and analysis of waste form and soil cores from the lysimeters. Results of partition coefficient determinations are presented, as well as application of a source term computer code using those coefficients to predict the lysimeter results. A study of radionuclide-containing colloids associated with the leachate waters removed from these lysimeters is described. An update of upward migration of radionuclides in the sand-filled lysimeter at ORNL is included.

  4. Field lysimeter investigations: Low-level waste data base development program for fiscal year 1995. Volume 8, Annual report, October 1994-- September 1995

    SciTech Connect

    McConnell, J.W. Jr.; Rogers, R.D.; Larsen, I.L.; Jastrow, J.D.; Sanford, W.E.; Sullivan, T.M.

    1996-06-01

    The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the U.S. Nuclear Regulatory Commission, is (a) studying the degradation effects in organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified ion-exchange resins, (c) obtaining performance information on solidified ion- exchange resins in a disposal environment, and (d) determining the condition of liners used to dispose the ion-exchange resins. Compressive test results of 12-year-old cement and vinyl ester- styrene solidified waste form samples are presented, which show effects of aging and self-irradiation. Results of the tenth year of data acquisition from the field testing are presented and discussed. During the continuing field testing, both portland type I-II cement and Dow vinyl ester-styrene waste form samples are being tested in lysimeter arrays located at Argonne National Laboratory-East in Illinois and at Oak Ridge National Laboratory. The study is designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over a 20-year period.

  5. Field Lysimeter Investigations - test results: Low-Level Waste Data Base Development Program: Test results for fiscal years 1994-1995

    SciTech Connect

    McConnell, J.W. Jr.; Rodgers, R.D.; Hilton, L.D.; Neilson, R.M. Jr.

    1996-06-01

    The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the U.S. Nuclear Regulatory Commission (NRC), is (1) studying the degradation effects in EPICOR-II organic ion-exchange resins caused by radiation, (2) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified EPICOR-II resins, (3) obtaining performance information on solidified EPICOR-II ion-exchange resins in a disposal environment, and (4) determining the condition of EPICOR-II liners. Results of the final 2 (10 total) years of data acquisition from operation of the field testing are presented and discussed. During the continuing field testing, both portland type I-II cement and Dow vinyl ester-styrene waste forms are being tested in lysimeter arrays located at Argonne National Laboratory-East in Illinois and at Oak Ridge National Laboratory. The experimental equipment is described and results of waste form characterization using tests recommended by the NRC`s {open_quotes}Technical Position on Waste Form{close_quotes} are presented. The study is designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over a 20-year period. At the end of the tenth year, the experiment was closed down. Examination of soil and waste forms is planned to be conducted next and will be reported later.

  6. Field lysimeter investigations - test results. Low-level waste data base development program: Test results for fiscal years 1986, 1987, 1988, and 1989

    SciTech Connect

    McConnell, J.W. Jr.; Rogers, R.D.; Findlay, M.W.; Davis, E.C.; Jastrow, J.D.; Neilson, R.M. Jr.; Hilton, L.D.

    1995-05-01

    The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the U.S. Nuclear Regulatory Commission (NRC), is (a) studying the degradation effects in EPICOR-II organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified EPICOR-II resins, (c) obtaining performance information on solidified EPICOR-II ion-exchange resins in a disposal environment, and (d) determining the condition of EPICOR-II liners. Results of the first 4 years of data acquisition from the field testing are presented and discussed. During the continuing field testing, both Portland type I-II cement and Dow vinyl ester-styrene waste forms are being tested in lysimeter arrays located at Argonne National Laboratory-East in Illinois and at Oak Ridge National Laboratory. The experimental equipment is described and results of waste form characterization using tests recommended by the NRC`s {open_quotes}Technical Position on Waste Form{close_quotes} are presented. The study is designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over a 20-year period.

  7. Field Lysimeter Investigations -- Test results. Low-Level Waste Data Base Development Program: Test results for fiscal years 1990, 1991, 1992, and 1993; Volume 2

    SciTech Connect

    McConnell, J.W. Jr.; Rogers, R.D.; Brey, R.R.; Neilson, R.M. Jr.; Hilton, L.D.; Jastrow, J.D.; Wickliff Hicks, D.S.; Sanford, W.E.; Sullivan, T.M.

    1995-12-01

    The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the US Nuclear Regulatory Commission (NRC), is (a) studying the degradation effects in EPICOR-II organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified EPICOR-II resins, (c) obtaining performance information on solidified EPICOR-II ion-exchange resins in a disposal environment, and (d) determining the condition of EPICOR-II liners. Results of the second 4 years of data acquisition from the field testing are presented and discussed. During the continuing field testing, both portland type 1--2 cement and Dow vinyl ester-styrene waste forms are being tested in lysimeter arrays located at Argonne National Laboratory-East in Illinois and at Oak Ridge National Laboratory. The experimental equipment is described and results of waste form characterization using tests recommended by the NRC`s ``Technical Position on Waste Form`` are presented. The study is designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over a 20-year period.

  8. An arid zone lysimeter facility for performance assessment and closure investigations at the Nevada Test Site

    SciTech Connect

    Levitt, D.G.; Lohrstorfer, C.F.; Sully, M.J.; Ginanni, J.M.

    1996-07-01

    Two precision weighing lysimeters were installed near the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada Test Site to provide support for investigations of water, solute, and heat fluxes in the near-surface of the soil. The lysimeters consist of soil tanks with a volume of 16 cubic meters mounted on a sensitive scale. One lysimeter was revegetated with native shrubs whereas the other was kept bare to stimulate a non-vegetated waste cover. Data consisting of physical and hydrological properties of the lysimeter soils, thermal and moisture conditions in the lysimeters, and atmospheric boundary conditions are being collected for calibrating and verifying computer models for simulating the flow of water and heat in the near surface alluvium at the Area 5 RWMS. This effort will provide site- specific models for demonstration of ``no migration`` of constituents to the water table. Moisture and thermal conditions in the lysimeters are monitored daily using time domain reflectometry probes and thermocouple psychrometers. Daily evaporation and evapotranspiration are calculated from the lysimeter scales. Meteorological variables are monitored by sensors mounted on a 3 meter tower adjacent to the lysimeters. An array of soil-solution samplers to be installed through the side of the soil tank will allow studies of waste mobility under natural conditions. Conceptual designs for closure at the RWMS are focused on using an upper layer of repacked native alluvium, which can be tested with the lysimeters. In addition, performance of other components such as a capillary barrier can be tested by installing a scaled version in one of the lysimeter tanks.

  9. Investigation of the low-level modulated light action

    NASA Astrophysics Data System (ADS)

    Antonov, Sergei N.; Sotnikov, V. N.; Koreneva, L. G.

    1994-07-01

    Now there exists no clear complete knowledge about mechanisms and pathways by which low level laser bioactivation works. Modulated laser light action has been investigated two new ways: dynamical infrared thermography and computing image of living brain. These ways permit observation in real time laser action on peripheral blood flow, reflex reactions to functional probes, thermoregulation mechanisms as well as brain electrical activity changes of humans. We have designed a universal apparatus which produced all regimes of the output laser light. It has a built-in He-Ne laser with an acousto-optic modulator and an infrared GaAs laser. The device provided spatial combination of both the light beams and permitted us to irradiate an object both separately and simultaneously. This research shows that the most effective frequencies range from several to dozens of hertz. The duty factor and frequency scanning are also important. On the basis of these results in Russian clinics new treatment methods using modulated light are applied in practical neurology, gynecology, etc.

  10. Lysimeter Soil Retriever (LSR) - A tool for investigation on heterogeneity of the migration and structural changes

    NASA Astrophysics Data System (ADS)

    Reth, S.; Gierig, M.; Winkler, J. B.; Mueller, C. W.; Nitsche, C.; Seyfarth, M.

    2009-04-01

    Generally research fields of lysimeter studies scheduled as long term experiments. In the course of the studies, the lysimeters act more or less as a "black box". Usually the soil material is identified and analysed at the beginning of the experiments. But there is also a strong need to analyze the soil without disturbance of the soil structure after the experiments in order to obtain information about spatial and structural changes within the soil profile. The new technique of the Lysimeter Soil Retriever for the first time enables studies on the heterogeneous migration of percolating water, and changes of soil structure as well as soil organic matter (SOM) and biomass distribution, as well as the distribution of mycorrhiza and microbes in different depths on intact soil profiles. The main target by using the LSR is the preparation of an intact soil monolith from the field lysimeter and the immediate dissection into slices to enable a direct sampling of its soil environment at several depths. Distribution and composition of SOM, pF-values, soil porosity, as well as degradation of PAH were only a few parameters, which are determined at the different soil depths. In this presentation we give some examples for the different application of the LSR and the advantage for the experiments: - The soil of 8 lysimeters, planted with young beeches was retrieved after several years of fumigation with doubled atmospheric ozone concentrations and application of fungi. Due to the accurate sectioning of the soil monoliths a very dense and intensive soil sampling was possible. As the whole soil space of 8 lysimeters could be sampled, precise spatial information were obtained about the rapid formation of SOM depth gradients within the experiment duration. - After the investigation on the mobilization of polycyclic aromatic hydrocarbons (PAH) by the seepage water, the lysimeter soil was retrieved. Investigations on the microbiological degradation of the PAH were possible in the whole

  11. Lysimeter Platform

    NASA Astrophysics Data System (ADS)

    Klammler, Gernot; Murer, Erwin; Plieschnegger, Markus

    2014-05-01

    The existing European Lysimeter Platform (www.lysimeter.at/HP_EuLP) provides an overview of lysimeter types used in Europe and show details on equipment, research results and future perspectives of lysimeter facilities. However, this platform is not user-editable and has not been updated since 2008. Thus, the Lysimeter Research Group (www.lysimeter.at) intends to serve a new database based website called Lysimeter Platform, where existing information of the former European Lysimeter Platform will be transferred to the new Lysimeter Platform and, furthermore, registered users are able to create and edit sites where lysimeters, soil water samplers and soil hydrologic measuring profiles are operated. The Lysimeter Research Group is a scientific association and, therefore, the membership is free of charge. The new Lysimeter Platform contains general information of lysimeter sites worldwide (e.g., what is measured at which site) in a standardized form to get a quick but informative overview of the sites and can be linked to more detailed, already existing information provided by the site operators. Due to the standardized information in the database the Lysimeter Platform serves also as search-engine for soil water measurements and helps to find sites of interest and corresponding contact information worldwide. The Session "Estimation of soil-atmosphere and vadose zone water fluxes by use of precision lysimeter measurements" at the EGU General Assembly 2014 would be an excellent chance to present the idea and the concept of this new Lysimeter Platform to international site operators and scientists.

  12. Compound specific isotope analysis to investigate pesticide degradation in lysimeter experiments at field conditions

    NASA Astrophysics Data System (ADS)

    Ryabenko, Evgenia; Elsner, Martin; Bakkour, Rani; Hofstetter, Thomas; Torrento, Clara; Hunkeler, Daniel

    2015-04-01

    mixtures and c) transformation of pesticides in lysimeters during the year 2014. 1 Elsner, M. Stable isotope fractionation to investigate natural transformation mechanisms of organic contaminants: principles, prospects and limitations. J. Environ. Monit. 12, 2005-2031 (2010). 2 Hofstetter, T. B. & Berg, M. Assessing transformation processes of organic contaminants by compound-specific stable isotope analysis. TrAC Trends in Analytical Chemistry 30, 618-627 (2011). 3 Elsner, M. et al. Current challenges in compound-specific stable isotope analysis of environmental organic contaminants. Anal. Bioanal. Chem. 403, 2471-2491, doi:10.1007/s00216-011-5683-y (2012).

  13. Deep Lysimeter

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    2004-06-01

    A deep lysimeter including a hollow vessel having a chamber, a fill conduit extending into the chamber through apertures, a semi-permeable member mounted on the vessel and in fluid communication with the fill conduit, and a line connection for retrieving the lysimeter.

  14. Lysimeter apparatus

    DOEpatents

    Clark, Don T.; Erickson, Eugene E.; Casper, William L.; Everett, David M.; Hubbell, Joel M.; Sisson, James B.

    2005-09-06

    A suction lysimeter for sampling subsurface liquids includes a lysimeter casing having a drive portion, a reservoir portion, and a tip portion, the tip portion including a membrane through which subsurface liquids may be sampled; a fluid conduit coupled in fluid flowing relation relative to the membrane, and which in operation facilitates the delivery of the sampled subsurface liquids from the membrane to the reservoir portion; and a plurality of tubes coupled in fluid flowing relation relative to the reservoir portion, the tubes in operation facilitating delivery of the sampled subsurface liquids from the reservoir portion for testing. A method of sampling subsurface liquids comprises using this lysimeter.

  15. The Bushland weighing lysimeters: A quarter century of crop ET investigations to advance sustainable irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 1987-1989, the first irrigated crops were grown on the four large, precision weighing lysimeters at the USDA-ARS Conservation & Production Laboratory on the Southern High Plains (SHP) at Bushland, Texas. Thus began >25-years of full- and deficit-irrigated crop growth, energy and water balance, ev...

  16. The Bushland weighing lysimeters: A quarter century of crop ET investigations to advance sustainable irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 1987-1989, the first irrigated crops were grown on the four large, precision weighing lysimeters at the USDA-ARS Laboratory at Bushland, Texas, on the Southern High Plains (SHP). Thus began >25-years of full- and deficit-irrigated crop growth, energy and water balance, evapotranspiration (ET), yi...

  17. An Investigation of Topography Modulated Low Level Moisture Convergence Patterns in the Southern Appalachians Using WRF

    NASA Astrophysics Data System (ADS)

    Wilson, A. M.; Duan, Y.; Barros, A.

    2015-12-01

    The Southern Appalachian Mountains (SAM) region is a biodiversity hot-spot that is vulnerable to land use/land cover changes due to its proximity to the rapidly growing population in the Southeast U.S. Persistent near surface moisture and associated microclimates observed in this region have been documented since the colonization of the area. The landform in this area, in particular in the inner mountain region, is highly complex with nested valleys and ridges. The geometry of the terrain causes distinct diurnal and seasonal local flow patterns that result in highly complex interactions of this low level moisture with meso- and synoptic-scale cyclones passing through the region. The Weather Research and Forecasting model (WRF) was used to conduct high resolution simulations of several case studies of warm season precipitation in the SAM with different synoptic-scale conditions to investigate this interaction between local and larger-scale flow patterns. The aim is to elucidate the microphysical interactions among these shallow orographic clouds and preexisting precipitating cloud systems and identify uncertainties in the model microphysics using in situ measurements. Findings show that ridge-valley precipitation gradients, in particular the "reverse" to the classical orographic effect observed in inner mountain valleys, is linked to horizontal heterogeneity in the vertical structure of low level cloud and precipitation promoted through landform controls on local flow. Moisture convergence patterns follow the peaks and valleys as represented by WRF terrain, and the topography effectively controls their timing and spatial structure. The simulations support the hypothesis that ridge-valley precipitation gradients, and in particular the reverse orographic enhancement effect in inner mountain valleys, is linked to horizontal heterogeneity in the vertical structure of low level clouds and precipitation promoted through landform controls on moisture convergence.

  18. Investigation of low-level-jets over rural and urban areas using two sodars

    NASA Astrophysics Data System (ADS)

    Kallistratova, M. A.

    2008-05-01

    This paper is devoted to the experimental study of jet streams at heights up to 400 m agl (the so called Low-Level Jet, or LLJ) with the help of sodars. These LLJs, which are not connected either to catabatic winds or to synoptic front passing, but are regularly observed in the mid-latitudes over a flat terrain under nocturnal inversion conditions, are investigated. Preliminary results of simultaneous investigations of LLJs over the center of the Moscow megalopolis and over a nearby rural area are presented. Continuous sodar data on wind speed profiles collected during 27 days in July 2005 were analyzed together with in situ data from a meteorological mast. Empirical distributions of the maximum jet speed and the height of jet axis were obtained. The relationships between the LLJ parameters and some characteristics of the surface layer were found. Over the urban area, the jets appear less frequently and at greater heights than over the countryside.

  19. Low-level waste data base development - EPICOR II resin/liner investigation - a program review

    SciTech Connect

    McConnell, J.W. Jr.; Reno, H.W.; Schmitt, R.C.; Ayers, A.L. Jr.

    1986-01-01

    This paper presents an overview of the titled program and gives the status of the work on resin degradation, resin solidification, and field testing of solidified samples. A brief discussion of some recent results also is included. Resin materials from EPICOR-II prefilters used during cleanup of Three Mile Island Nuclear Power Station are being examined to (a) develop a data base for low-level waste and (b) obtain information on survivability of waste forms composed of ion exchange media loaded with radionuclides and solidified in matrices of cement and Dow polymer. An unusual aspect of the investigation is the use of commercial grade resins which have been loaded with over five times the radioactivity normally seen in a commercial application. That dramatically increases the total radiation dose to the resins. 21 refs., 8 figs.

  20. Low level waste data base development - EPICOR-II resin/liner investigation. Program review

    SciTech Connect

    McConnell, J.W. Jr.

    1985-09-10

    This paper presents an overview of the titled program and gives the status of the work on resin degradation, resin solidification, and field testing of solidified samples. A brief discussion of some recent results is also included. Resin materials from EPICOR-II prefilters used in the cleanup of the Three Mile Island Nuclear Power Station are being examined to (1) develop a low level waste data base and (2) obtain information on survivability of waste forms composed of ion exchange media loaded with radionuclides and solidified in matrices of cement and Dow polymer. An unusual aspect of this investigation is the use of commercial grade resins which have been loaded with over five times the radioactivity normally seen in a commercial application. That dramatically increases the total radiation dose to the resins. 18 refs., 8 figs.

  1. Lysimeter Research Group - A scientific community network for lysimeter research

    NASA Astrophysics Data System (ADS)

    Cepuder, Peter; Nolz, Reinhard; Bohner, Andreas; Baumgarten, Andreas; Klammler, Gernot; Murer, Erwin; Wimmer, Bernhard

    2014-05-01

    A lysimeter is a vessel that isolates a volume of soil between ground surface and a certain depth, and includes a sampling device for percolating water at its bottom. Lysimeters are traditionally used to study water and solute transport in the soil. Equipped with a weighing system, soil water sensors and temperature sensors, lysimeters are valuable instruments to investigate hydrological processes in the system soil-plant-atmosphere, especially fluxes across its boundary layers, e.g. infiltration, evapotranspiration and deep drainage. Modern lysimeter facilities measure water balance components with high precision and high temporal resolution. Hence, lysimeters are used in various research disciplines - such as hydrology, hydrogeology, soil science, agriculture, forestry, and climate change studies - to investigate hydrological, chemical and biological processes in the soil. The Lysimeter Research Group (LRG) was established in 1992 as a registered nonprofit association with free membership (ZVR number: 806128239, Austria). It is organized as an executive board with an international scientific steering committee. In the beginning the LRG focused mainly on nitrate contamination in Austria and its neighboring countries. Today the main intention of the LRG is to advance interdisciplinary exchange of information between researchers and users working in the field of lysimetry on an international level. The LRG also aims for the dissemination of scientific knowledge to the public and the support of decision makers. Main activities are the organization of a lysimeter conference every two years in Raumberg-Gumpenstein (Styria, Austria), the organization of excursions to lysimeter stations and related research sites around Europe, and the maintenance of a website (www.lysimeter.at). The website contains useful information about numerous European lysimeter stations regarding their infrastructure, instrumentation and operation, as well as related links and references which

  2. Cultural Resource Investigations for the Remote Handled Low Level Waste Facility at the Idaho National Laboratory

    SciTech Connect

    Brenda R. Pace; Hollie Gilbert; Julie Braun Williams; Clayton Marler; Dino Lowrey; Cameron Brizzee

    2010-06-01

    The U. S. Department of Energy, Idaho Operations Office is considering options for construction of a facility for disposal of Idaho National Laboratory (INL) generated remote-handled low-level waste. Initial screening has resulted in the identification of two recommended alternative locations for this new facility: one near the Advanced Test Reactor (ATR) Complex and one near the Idaho Comprehensive Environmental Response, Compensation, and Liability Act Disposal Facility (ICDF). In April and May of 2010, the INL Cultural Resource Management Office conducted archival searches, intensive archaeological field surveys, and initial coordination with the Shoshone-Bannock Tribes to identify cultural resources that may be adversely affected by new construction within either one of these candidate locations. This investigation showed that construction within the location near the ATR Complex may impact one historic homestead and several historic canals and ditches that are potentially eligible for nomination to the National Register of Historic Places. No resources judged to be of National Register significance were identified in the candidate location near the ICDF. Generalized tribal concerns regarding protection of natural resources were also documented in both locations. This report outlines recommendations for protective measures to help ensure that the impacts of construction on the identified resources are not adverse.

  3. Investigation of {sup 14}C release in an engineered low-level waste disposal facility

    SciTech Connect

    Yim, M.S.; Simonson, S.A.; Sullivan, T.M.

    1996-05-01

    Atmospheric releases of {sup 14}C from a generic engineered low-level waste (LLW) disposal facility and its radiological impacts are investigated. A computer model that describes microbial gas generation and the transport has been developed and used to analyze the generation of {sup 14}C contaminated gases and subsequent migration in a facility. Models are based on a chemical kinetic description of aerobic and anaerobic decomposition of organic materials coupled with attending models of oxygen transport and consumption within waste containers in a facility. Effects of radiolysis on gas generation are addressed based on the estimated dose rate for class B and C wastes. Estimates predict that annual atmospheric release of {sup 14}C due to atmospheric pressure variations could range between {approximately}2.6 {times} 10{sup 8} and 5.5 {times} 10{sup 11} Bq as a result of microbial gas generation based on a volume of 48 000 m{sup 3} LLW disposed in a facility. The associated dose to a maximally exposed individual is estimated to be dominated by ingestion pathway and strongly depends on the fraction of the food imported from an uncontaminated outside area. Dose rates are expected to be <0.04 mSv/yr, considering a reasonable distance between the facility and the exposed population. The depletion through airborne releases of {sup 14}C inventory that is available for transport through other pathways is not expected to be a significant issue.

  4. Effect of Low-Level Laser Therapy on Orthodontic Tooth Movement: A Clinical Investigation

    PubMed Central

    Dalaie, Kazem; Kharazifard, Mohammad Javad; Mahdian, Mina; Bayat, Mehrdad

    2015-01-01

    Objectives: One major drawback of orthodontic treatment is its long duration due to slow tooth movement and the pain at the onset of treatment following application of forces. There is controversy regarding the efficacy of laser for decreasing the treatment time and pain of orthodontic treatment. The purpose of this study was to investigate the effect of low level diode laser on the rate of orthodontic tooth movement and the associated pain. Materials and Methods: In this double blind randomized controlled clinical trial, 12 orthodontic patients referring to Shahid Beheshti School of Dentistry for first premolar extraction were randomly selected and allocated to gallium aluminum-arsenide laser (GA-AL-AS diode laser, 880 nm, 100 mW, 5 j/cm2, 8 points, 80 seconds, continuous mode) or control group. The patients initially underwent leveling and alignment using the sectional system. Force (150 gr) was applied to each canine tooth via sectional closing loops. The loops were activated every month. The rate of tooth movement and pain were monitored over the treatment period and recorded on days 1, 3, 7, 30, 33, 37, 60, 63 and 67. Two-way ANOVA was used for comparison of groups. Results: There was no significant difference in terms of tooth movement and pain scores between the irradiated and non-irradiated sides at any time point (P>0.05). Conclusion: Although laser enhanced orthodontic tooth movement in the upper jaw, we failed to provide solid evidence to support the efficacy of laser for expediting tooth movement or reducing the associated pain. PMID:26622279

  5. Lysimeter study of vegetative uptake from saltstone

    SciTech Connect

    Murphy, C.E. Jr.

    1990-06-08

    At the Savannah River Site, liquid, low-level nuclear waste will be disposed of by incorporating the waste in concrete, a wasteform called saltstone. Saltstone monoliths will then be buried in the earth. To study the potential uptake of radionuclides by trees and other plants growing in the soil in the area containing buried saltstone, a lysimeter study has been in progress since 1984. Thirty two lysimeters were designed, constructed, and filled with soil. Saltstone samples, containing the liquid, low-level supernate from the tank 50 in-tank precipitation demonstration, were buried in some of the lysimeters. Other lysimeters, not containing saltstone, were used as controls. Crops, grass, and trees were planted in the lysimeters and sampled periodically to determine radionuclide concentrations. Water samples were also collected from the lysimeter sumps and analyzed for radionuclide content. This report documents the results of vegetative and lysimeter sump water measurements from the beginning of the project in November of 1984 through September of 1989. 6 refs., 22 figs., 6 tabs.

  6. Measurement of precipitation using lysimeters

    NASA Astrophysics Data System (ADS)

    Fank, Johann; Klammler, Gernot

    2013-04-01

    wind speeds and the measured outliers of lysimeter mass. Moreover, the influence of wind seems to be varying for different lysimeters. At the agricultural test site Wagna, Austria, two precipitation gauges in high temporal resolution (weighing-recording gauge and tipping-bucket gauge; both 200 cm² surface; measuring height 1.5 m) are installed. Furthermore, mass time series of various lysimeters cultivated with different vegetation is also available for the same location. Appropriate methods to compensate the influence of wind on measuring precipitation using lysimeters are investigated and results between the different measuring devices are compared. Results show that precipitation measured with lysimeters is generally higher, especially compared to the weighing-recording gauge. In addition it is detected that also the data interval of lysimeter mass time series used for quantifying precipitation (e.g., 1 day, 1 hour, 30 minutes, 10 minutes) is a crucial factor and influences the result. Summarizing, the potential of using highly precise weighable lysimeters for measuring precipitation at the point scale is rather high. However, methods used to compensate external effects on lysimeter weighing have to be enhanced for a global application of using lysimeters as precipitation gauges. Meissner, R., J. Seeger, H. Rupp, M. Seyfarth & H. Borg, 2007: Measurement of dew, fog, and rime with a high-precision gravitation Lysimeter. J. Plant Nutr. Soil Sci. 2007, 170, p. 335-344. WMO (World Meteorological Organization), 2008. Guide to Meteorological Instruments and Methods of Observation. WMO-No. 8, 140 pp.

  7. Investigation of low level neutron radiation on tantalum alloys for radioisotope power system applications

    NASA Astrophysics Data System (ADS)

    Barklay, Chadwick Douglas

    2007-12-01

    Tantalum alloys have been used by the U.S. Department of Energy (USDOE) as structural materials for space nuclear power systems such as Radioisotopic Thermoelectric Generators (RTG) since the 1960s. The thrust of this thesis research is to investigate the effects of low-level neutron radiation on the mechanical and microstructural properties of two tantalum alloys, Ta-10%W and T-111 (Ta-8%W-2%Hf), which have been used to encapsulate radioactive fuel for space nuclear power systems. Ta-10%W and T-111 test specimens were exposed to a neutron fluence level (1.2 x 1015 nvt) at temperatures less than <0.2 Tm, which is equivalent to the cumulative fluence associated with the 30-year mission life of a RTG. This fluence level resulted in an atomic displacement damage of approximately 3.0 x 10-7 dpa in both alloys. In T-111 test specimens, this level of atomic displacement damage produced an approximate 6.6% reduction in the tensile ductility, an approximate two-order of magnitude increase in the stress rupture time, and a two-order of magnitude reduction in steady state creep rate. These observations are statistically significant at the 0.05 significance level. Through the employment of Transmission Electron Microscopy it was determined that the interaction of the defects produced by atomic displacement damage with moving ao/2<111> screw dislocations increased the magnitude of cross-slip of the screw dislocations, thus leading to a five-fold increase in dislocation density and a pronouncement of the ordering of dislocations into mosaic patterns of cellular or subgranular arrangements at the boundaries of cells/subgrains. In addition, the experimental results determined that an atomic displacement damage of approximately 3.0 x 10-7 dpa did not produce a statistically significant effect on the mechanical or microstructural properties of Ta-10%W when subjected to a strain rate of 0.0017 s-1. The culmination of this research is the development of a phenomenological model based

  8. Investigation of rainfall data with regard to low-level wind flow regime for east central Florida

    NASA Technical Reports Server (NTRS)

    Brooks, Joni

    1992-01-01

    Previous research has been conducted to investigate the effect of the low-level wind region on summertime convective storms in the east central Florida area. These effects were described by analyzing the distribution of lightning flashes within classifications based on the low-level wind regime for the months June through September of 1987 to 1990. The present research utilizes the same classification strategy to study rainfall patterns for data gathered for the CaPE (Convection and Precipitation/Electrification Experiment) field program. The CaPE field program was conducted in east central Florida from July 8, 1991 to August 18, 1991.

  9. Investigation of the liquid low-level waste evaporator steam coil failure and supporting laboratory studies

    SciTech Connect

    Pawel, S.J.; Keiser, J.R.; Longmire, H.F.

    1995-05-01

    Using a remote video camera, the internals of a low-level waste evaporator tank (termed 2A2, type 304L stainless steel construction, known to have failed steam coils) were inspected. This inspection revealed at least three rather substantial holes as opposed to crack- or pit-like leak sites near the nominal solution level position on one particular steam coil. This section was removed from the evaporator vessel, and subsequent hot cell examination revealed extensive general corrosion on the process side of the coil with little or no attack on the steam side. Hot cell metallography confirmed intense general corrosion on the process side and, in addition, revealed shallow intergranular attack at the leading edge of corrosion. No pits or cracks were detected in this section of the steam coil. Laboratory corrosion tests with coupons of 304L (and other high-alloy materials) isothermally exposed in a range of solutions similar to those expected in the evaporator reveal only very low corrosion rates below 40% sodium hydroxide and the solution boiling point. However, {open_quotes}dried film{close_quotes} experiments revealed that much more dilute solutions became aggressive to stainless steel due to concentrating effects (evaporation and periodic wetting) at the air/solution interface. The high general corrosion rates observed on the failed coil section occurred at or near the air/solution interface and were attributed to such {open_quotes}splash zone{close_quotes} activity.

  10. Effect of low-level laser therapy after rapid maxillary expansion: a clinical investigation.

    PubMed

    Garcia, Valentin Javier; Arnabat, J; Comesaña, Rafael; Kasem, Khaled; Ustrell, Josep Maria; Pasetto, Stefano; Segura, Oscar Pozuelo; ManzanaresCéspedes, Maria Cristina; Carvalho-Lobato, Patricia

    2016-08-01

    To evaluate the effectiveness low-level laser therapy (LLLT) on the repair of the mid palatal suture, after rapid maxillary expansion (RME). A single-operator, randomized single-blind placebo-controlled study was performed at the Orthodontic Department at the Dental Hospital of Bellvitge. Barcelona University, Hospitalet de Llobregat, Spain. Thirty-nine children (range 6-12 years old), completed RME and were randomized to receive active LLLT (n = 20) or placebo (n = 19). The laser parameters and dose were 660 nm, 100 mW, CW, InGaAlP laser, illuminated area 0.26 cm(2), 332 mW/cm(2), 60 s to four points along midpalatal suture, and 30 s to a point each side of the suture. A total of seven applications were made on days 1, 7, 14, 28, 42, 56, and 70 of the retention phase RME. A cone beam computed tomography (CBCT) scan was carried out on the day of the first laser treatment, and at day 75, a second CBCT scan was performed. Two radiologists synchronized the slices of two scans to be assessed. P = 0.05 was considered to be statistically significant. At day 75 of the suture, the irradiated patients presented a greater percentage of approximate zones in the anterior (p = 0.008) and posterior (p = 0.001) superior suture-and less approximation in the posterior superior suture (p = 0.040)-than the placebo group. LLLT appears to stimulate the repair process during retention phase after RME. PMID:27236292

  11. Is the diagnosis of mass hysteria an excuse for incomplete investigation of low-level environmental contamination

    SciTech Connect

    Faust, H.S.; Brilliant, L.B.

    1981-01-01

    Mass hysteria is an epidemic diagnostic term used to characterize unexplained outbreaks of syncope among women. A syncope outbreak among women in a meeting in a rural area of Michigan prompted an intense investigation to etiology. Low levels of ozone, carbon monoxide, and pentane were found associated with the outbreak. These levels were too low by themselves to explain the symptoms. A sociometric scale of intensity of illness was devised and found to be highly correlated (r = -.094) with the weight of those who fainted. It is argued that mass hysteria may be the result of interactions of low levels of toxicants and may not be a result of the hysterical behavior in women at all.

  12. Is the diagnosis of mass hysteria an excuse for incomplete investigation of low-level environmental contamination

    SciTech Connect

    Faust, H.S.; Brilliant, L.B.

    1981-01-01

    Mass hysteria is an epidemic diagnostic term used to characterize unexplained outbreaks of syncope among women. A syncope outbreak among women in a meeting in a rural area of Michigan prompted an intense investigation for etiology. Low levels of ozone, carbon monoxide, and pentane were found associated with the outbreak. These levels were too low by themselves to explain the symptoms. A sociometric scale of intensity of illness was devised and found to be highly correlated (r = -0.94) with the weight of those who fainted. It is argued that mass hysteria may be the result of interactions of low levels of toxicants and may not be a result of the hysterical behavior in women at all.

  13. Investigations with large-scale forest lysimeter research of the lowlands of Northeast Germany - Results and consequences for the choice of tree species and forest management

    NASA Astrophysics Data System (ADS)

    Müller, J.

    2009-04-01

    Investigations with large-scale forest lysimeter research of the lowlands of Northeast Germany - Results and consequences for the choice of tree species and forest management Introduction At present about 28 % - i.e. 1.9 million hectares - of the Northeast German Lowlands are covered with forests. The Lowlands are among the driest and at the same time the most densely wooded regions in Germany. The low annual precipitation between 500 and 600 mm and the light sandy soils with their low water storage capacity and a high porosity lead to a limited water availability. Therefore the hydrological functions of forests play an important role in the fields of regional water budget, water supply and water distribution. Experimental sites Lysimeters are suitable measuring instruments in the fields of granular soils and loose rocks to investgate evaporation and seepage water. The usage of lysimeter of different construction has a tradition of more than 100 years in this region. To investigate the water consumption of different tree species, lysimeters were installed at Britz near Eberswalde under comparable site conditions. In the early 1970s nine large-scale lysimeters were built with an area of 100 m2 and a depth of 5 m each. In 1974 the lysimeters were planted, together with their environment, with Scots pine (Pinus sylvestris L), common beech (Fagus sylvatica L.), larch (Larix decidua L.) and Douglas-fir (Pseudotsuga menziesii [Mirb.] FRANCO) as experimental stands of 0.5 ha each according to the usual management practices. Therefore the "Large-scale lysimeters of Britz" are unparalleled in Europe. It was the initial aim of the experiment to find out the influence of the species and age of the growing stock growing on identical sandy soil under comparable weather conditions on both natural groundwater recharge and evaporation. Future forests in the north-eastern lowlands of Germany shall be mixed stands with as large a number of different species as possible. And this is

  14. Lysimeter methods and apparatus

    DOEpatents

    Clark, Don T.; Erickson, Eugene E.; Casper, William L.; Everett, David M.; Hubbell, Joel M.; Sisson, James B.

    2004-12-07

    A suction lysimeter for sampling subsurface liquids includes a lysimeter casing having a drive portion, a reservoir portion, and a tip portion, the tip portion including a membrane through which subsurface liquids may be sampled; a fluid conduit coupled in fluid flowing relation relative to the membrane, and which in operation facilitates the delivery of the sampled subsurface liquids from the membrane to the reservoir portion; and a plurality of tubes coupled in fluid flowing relation relative to the reservoir portion, the tubes in operation facilitating delivery of the sampled subsurface liquids from the reservoir portion for testing. A method of sampling subsurface liquids comprises using this lysimeter.

  15. Evaluation of EPICOR-II Resin/Liner lysimeter investigation data using MIXBATH'' a one-dimensional transport code

    SciTech Connect

    McConnell, J.W.; Rogers, R.D. ); Brey, R.R. ); Sullivan, T.M. )

    1992-01-01

    The computer code MIXBATH has been applied to compare model predictions with six years of leachate collection data from five lysimeters located at Oak Ridge and five located at Argonne National Laboratories. The goal of this study was to critique the applicability of these data for use as a basis for the long-term prediction of release and transport of radionuclides contained in Portland type I-II cement and Dow vinyl ester-styrene waste forms loaded with EPICOR-II prefilter ion exchange resins. MIXBATH was useful in providing insight into information needs for long-term performance assessment. In most cases, the total activity released from the lysimeters over the test period was indistinguishable from background, indicating a need for longer-term data collection. In cases where there was both sufficient information available and activity released, MIXBATH was able to predict releases within an order of magnitude of those measured. Releases are extremely sensitive to the soil partition coefficient and waste form diffusion coefficient, and these were identified as the key data needs for long-term performance assessment.

  16. Evaluation of EPICOR-II Resin/Liner lysimeter investigation data using ``MIXBATH`` a one-dimensional transport code

    SciTech Connect

    McConnell, J.W.; Rogers, R.D.; Brey, R.R.; Sullivan, T.M.

    1992-08-01

    The computer code MIXBATH has been applied to compare model predictions with six years of leachate collection data from five lysimeters located at Oak Ridge and five located at Argonne National Laboratories. The goal of this study was to critique the applicability of these data for use as a basis for the long-term prediction of release and transport of radionuclides contained in Portland type I-II cement and Dow vinyl ester-styrene waste forms loaded with EPICOR-II prefilter ion exchange resins. MIXBATH was useful in providing insight into information needs for long-term performance assessment. In most cases, the total activity released from the lysimeters over the test period was indistinguishable from background, indicating a need for longer-term data collection. In cases where there was both sufficient information available and activity released, MIXBATH was able to predict releases within an order of magnitude of those measured. Releases are extremely sensitive to the soil partition coefficient and waste form diffusion coefficient, and these were identified as the key data needs for long-term performance assessment.

  17. The Site Investigation Of Low-Level Radioactive Waste For Sub-Surface Disposal Facility In Japan

    NASA Astrophysics Data System (ADS)

    Hosoya, S.; Sasaki, T.

    2006-12-01

    [1.Concept of the sub-surface disposal facility] In Japan, the facilities of Low-Level Radioactive West (LLW) for near-surface disposal have already been in operation. Japan Nuclear Fuel Limited (JNFL) has a plan of a new facility of LLW for sub-surface disposal with engineered barrier, for short "the sub-surface disposal facility".This facility can accept the relatively higher low-level waste from unclear power plant operation and in core materials from the decommissioning, estimated about 20 thousands cubic meter in total.In addition, this will accept transuranim (TRU) slightly contaminated waste from reprocessing plant operation and decommissioning. It shall be located at a sufficient depth enough to avoid normal human activities in future. [2.Site investigation] From 2001 to 2006,the site investigation on geology and hydrogeology has been performed in order to acquire the basic data for the design and the safety assessment for the sub-surface disposal facility.The candidate area is located at the site of JNFL, where Rokkasho-mura, Aomori Prefecture in the northern area of the Mainland of Japan.To confirm geology hydraulic conditions and geo-chemistry, 22 boring survey including 6 holes in swamp and marsh have been performed. The 1km long access tunnel (the entrance level EL 8.0m, incline of 1/10) to the altitude of EL -86m underground, around 100m depth from surface, has excavated. During excavating the tunnel, observation of geology, permeability tests, pore water pressure measurements and so on has been performed in situ.And the large size test cavern of 18m diameters was constructed at the end of the tunnel to demonstrate stability of the tunnel. Prior to the excavation, 3 measuring tunnels were excavated surrounding the test cavern to examine the excavation. [3.Geological features] The sedimentary rock called Takahoko formation at the Neogene period is distributed upper than EL-500m in the candidate area.The quaternary stratum about 10m in thickness is

  18. Lysimeter literature review

    SciTech Connect

    Rogers, R.D.; McConnell, J.W. Jr.

    1993-08-01

    Many reports have been published concerning the use of lysimeters to obtain data on the performance of buried radioactive waste. This document presents a review of some of those reports. This review includes lysimeter studies using radioactive waste forms at Savannah River Site, Hanford Site, Argonne National Laboratory, and Oak Ridge National Laboratory; radionuclide tracer studies at Whiteshell Nuclear Research Establishment and Los Alamos National Laboratory; and water movement studies at the Nuclear Regulatory Commission`s Beltsville, Maryland site, at the Hanford Site, and at New Mexico State University. The tests, results, and conclusions of each report are summarized, and conclusions concerning lysimeter technology are presented from an overall analysis of the literature. 38 refs., 44 figs., 9 tabs.

  19. Portable Suction Lysimeter

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    2004-07-13

    A portable lysimeter including a collection vessel having an inflatable bladder and a semi-permeable member assembly at least partially movable in response to inflation of the bladder, a sample conduit in fluid communication with the semi-permeable member and a reservoir in fluid communication with the sample conduit.

  20. Paramecium tetraurelia growth stimulation under low-level chronic irradiation: investigations on a possible mechanism. [/sup 60/Co

    SciTech Connect

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H.

    1982-12-01

    Experiments were carried out to demonstrate the effects of low-level chronic irradiation on Paramecium tetraurelia proliferation. Biological effects were strongly dependent on the bacterial density of culture medium and more exactly on the catalase content of the medium. Significant growth stimulation was found under /sup 60/Co chronic irradiation at a dose rate of 2 rad/year when paramecia were grown in a medium containing a high bacterial concentration (2.5 x 10/sup 2/ cells/m) or supplemented with catalase (300 U/ml). In a medium with a low bacterial density (1 x 10/sup 6/ cell/ml) or supplemented with a catalase activity inhibitor, growth simulation was preceded by a transitory inhibiting effect which could be correlated with extracellularly radioproduced H/sub 2/O/sub 2/. H/sub 2/O/sub 2/ addition appeared to be able to simulate the biological effects of chronic irradiation. A possible mechanism is discussed.We proposed that the stimulating effects were the result of intracellular enzymatic scavenging of radioproduced H/sub 2/O/sub 2/.

  1. An investigation into the depth of penetration of low level laser therapy through the equine tendon in vivo

    PubMed Central

    2007-01-01

    Low level laser therapy (LLLT) is frequently used in the treatment of wounds, soft tissue injury and in pain management. The exact penetration depth of LLLT in human tissue remains unspecified. Similar uncertainty regarding penetration depth arises in treating animals. This study was designed to test the hypothesis that transmission of LLLT in horses is increased by clipping the hair and/or by cleaning the area to be treated with alcohol, but is unaffected by coat colour. A LLLT probe (810 nm, 500 mW) was applied to the medial aspect of the superficial flexor tendon of seventeen equine forelimbs in vivo. A light sensor was applied to the lateral aspect, directly opposite the laser probe to measure the amount of light transmitted. Light transmission was not affected by individual horse, coat colour or leg. However, it was associated with leg condition (F = 4.42, p = 0.0032). Tendons clipped dry and clipped and cleaned with alcohol, were both associated with greater transmission of light than the unprepared state. Use of alcohol without clipping was not associated with an increase in light transmission. These results suggest that, when applying laser to a subcutaneous structure in the horse, the area should be clipped and cleaned beforehand. PMID:21851694

  2. Method of retrieving a liquid sample, a suction lysimeter, a portable suction lysimeter, a lysimeter system, and a deep lysimeter

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    2003-08-26

    A method of retrieving a liquid sample comprises providing a portable lysimeter including a semi-permeable membrane and a chamber in fluid communication with the semi-permeable membrane; making a hole at a site from which a liquid sample is desired; evacuating the chamber by applying a vacuum to the chamber; lowering the portable lysimeter into the hole; obtaining a sample in the chamber; and retrieving the lysimeter from the bore; wherein it is not necessary to backfill the bore. A portable lysimeter includes a semi-permeable member and a chamber in fluid communication with the semi-permeable membrane.

  3. Investigations of Possible Low-Level Temperature and Moisture Anomalies During the AMIE Field Campaign on Manus Island

    SciTech Connect

    Long, CN; Holdridge, DJ

    2012-11-19

    This document discusses results stemming from the investigation of near-surface temperature and moisture “oddities” that were brought to light as part of the Atmospheric Radiation Measurement (ARM) Madden-Julian Oscillation (MJO) Investigation Experiment (AMIE), Dynamics of the Madden-Julian Oscillation (DYNAMO), and Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011 (CINDY2011) campaigns.

  4. Low-level liquid waste disposal at the Savannah River Site: A large scale demonstration of saltstone

    SciTech Connect

    Clark, S.B.; Wilhite, E.L.

    1990-12-31

    Lysimeters are large-scale, field experiments used at the Savannah River Site (SRS) to measure the effect of percolating rainfall on the release of contaminants from wasteforms. The saltstone lysimeters described are demonstrations of a disposal concept for a low-level radioactive waste resulting from the processing of high-level defense waste for vitrification. Results from the lysimeters confirm the efficacy of the slag formulation in retaining chromium and technetium. Lysimeter results were also useful in validating mathematical models used in predicting environmental effects of saltstone disposal in engineered vaults. 7 refs., 3 figs., 4 tabs.

  5. Low-level liquid waste disposal at the Savannah River Site: A large scale demonstration of saltstone

    SciTech Connect

    Clark, S.B.; Wilhite, E.L.

    1990-01-01

    Lysimeters are large-scale, field experiments used at the Savannah River Site (SRS) to measure the effect of percolating rainfall on the release of contaminants from wasteforms. The saltstone lysimeters described are demonstrations of a disposal concept for a low-level radioactive waste resulting from the processing of high-level defense waste for vitrification. Results from the lysimeters confirm the efficacy of the slag formulation in retaining chromium and technetium. Lysimeter results were also useful in validating mathematical models used in predicting environmental effects of saltstone disposal in engineered vaults. 7 refs., 3 figs., 4 tabs.

  6. A piloted simulation investigation of yaw dynamics requirements for turreted gun use in low-level helicopter air combat

    NASA Technical Reports Server (NTRS)

    Decker, William A.; Morris, Patrick M.; Williams, Jeffrey N.

    1988-01-01

    A piloted, fixed-base simulation study was conducted to investigate the handling qualities requirements for helicopter air-to-air combat using turreted guns in the near-terrain environment. The study used a version of the helicopter air combat system developed at NASA Ames Research Center for one-on-one air combat. The study focused on the potential trade-off between gun angular movement capability and required yaw axis response. Experimental variables included yaw axis response frequency and damping and the size of the gun-movement envelope. A helmet position and sighting system was used for pilot control of gun aim. Approximately 340 simulated air combat engagements were evaluated by pilots from the Army and industry. Results from the experiment indicate that a highly-damped, high frequency yaw response was desired for Level I handling qualities. Pilot preference for those characteristics became more pronounced as gun turret movement was restricted; however, a stable, slow-reacting platform could be used with a large turret envelope. Most pilots preferred to engage with the opponent near the own-ship centerline. Turret elevation restriction affected the engagement more than azimuth restrictions.

  7. Atomic force microscopy investigation of the interaction of low-level laser irradiation of collagen thin films in correlation with fibroblast response.

    PubMed

    Stylianou, Andreas; Yova, Dido

    2015-12-01

    Low-level red laser (LLRL)-tissue interactions have a wide range of medical applications and are garnering increased attention. Although the positive effects of low-level laser therapy (LLLT) have frequently been reported and enhanced collagen accumulation has been identified as one of the most important mechanisms involved, little is known about LLRL-collagen interactions. In this study, we aimed to investigate the influence of LLRL irradiation on collagen, in correlation with fibroblast response. Atomic force microscopy (AFM) and fluorescence spectroscopy were used to characterize surfaces and identify conformational changes in collagen before and after LLRL irradiation. Irradiated and non-irradiated collagen thin films were used as culturing substrates to investigate fibroblast response with fluorescence microscopy. The results demonstrated that LLRL induced small alterations in fluorescence emission and had a negligible effect on the topography of collagen thin films. However, fibroblasts cultured on LLRL-irradiated collagen thin films responded to LRLL. The results of this study show for the first time the effect of LLRL irradiation on pure collagen. Although irradiation did not affect the nanotopography of collagen, it influenced cell behavior. The role of collagen appears to be crucial in the LLLT mechanism, and our results demonstrated that LLRL directly affects collagen and indirectly affects cell behavior. PMID:26498450

  8. Investigation of the Relationship Between Turbulence and Drizzle Onset and Development in Continental and Marine Stratiform Low-level Clouds Using ARM Observations

    NASA Astrophysics Data System (ADS)

    Luke, E. P.; Borque, P.; Chiu, J. Y. C.; Kollias, P.

    2014-12-01

    The response of shallow cloud systems to changes in atmospheric greenhouse gases and aerosols is a major source of uncertainty limiting the accuracy of predictions of future climate. Factors contributing to this uncertainty are drizzle formation and intensity. Drizzle is ubiquitous in low-level clouds, and the two primary parameters that control the production (autoconversion) and development (accretion) of drizzle are liquid water path (LWP) and aerosol loading. While LWP is the dominant parameter controlling the production and development of drizzle, several numerical studies and field observations have provided evidence of an aerosol role in drizzle suppression. However, it remains unclear to what extent small-scale turbulence influences the production and development of drizzle in low-level stratiform clouds. Here, we use observations from the US Department of Energy Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) deployments in the Black Forest, Germany, from April to December 2007 and at the Azores from June 2009 to December 2010. Several days of continental and maritime stratocumulus clouds are identified. Using synergy between ground-based aerosol observing systems and active and passive remote-sensing instruments, time series of LWP, cloud condensation nuclei (CCN) number concentration (NCCN), and cloud base drizzle rate (RCB) are derived (Mann et al., 2014). This dataset is conditionally sampled with respect to LWP and NCCN, and for each subset within a specific range of LWP and NCCN values, several additional parameters are estimated to provide information on drizzle onset, drizzle growth and in-cloud turbulence. In particular, the profiling cloud radar Doppler spectra dataset is used to estimate the radar Doppler spectrum skewness, a particularly sensitive parameter in the detection of drizzle onset (Kollias et al., 2011). The rate of drizzle growth is determined using average profiles of radar reflectivity and mean Doppler velocity. In

  9. Use of Long-Term Lysimeter Data in Support of Shallow Land Waste Disposal Cover Design

    SciTech Connect

    Desotell, L.T.; Hudson, D.B.; Yucel, V.; Carilli, J.T.

    2006-07-01

    Water balance studies using two precision weighing lysimeters have been conducted at the Nevada Test Site in support of low-level radioactive waste disposal since 1994. The lysimeters are located in northern Frenchman Flat approximately 400 meters (m) from the southwest corner of the Area 5 Radioactive Waste Management Site. Frenchman Flat is in the northern Mojave Desert and has an average annual precipitation of 125 millimeters (mm). Each lysimeter consists of a 2 m by 4 m by 2 m deep steel tank filled with native alluvium, supported on a sensitive scale. The scale is instrumented with an electronic load-cell and data-logger for continuous measurement of total soil water storage with a precision of approximately {+-}800 grams or {+-}0.1 mm of soil water storage. Data-loggers are linked to cell phone modems for remote data acquisition. One lysimeter is vegetated with native creosote bush, four wing salt bush, and annual grass at the approximate density of the surrounding landscape while the other is maintained as bare soil. Since no drainage has been observed from the bottom of the lysimeters and run-on/run-off is precluded, the change in soil-water storage is equal to precipitation minus evaporation/evapotranspiration. After equilibration, the bare lysimeter contains approximately 20.2 centimeters (cm) of water (10.1 % volumetric water content) and the vegetated lysimeter contains approximately 11.6 cm of water (5.8 % volumetric water content). The finite difference code UNSAT-H was used to simulate the continuous water balance of the lysimeters. Calibrated one-dimensional model simulations were generally in agreement with field data. 30-year model simulations were conducted to evaluate long-term potential transport of radionuclides via the soil water migration pathway. A 30-year climate record was generated by repeating the existing data record. Simulations indicate a 2 m thick closure cover, in conjunction with native vegetation, will essentially eliminate

  10. Simultaneous estimation of precipitation and actual evapotranspiration by lysimeters - Comparison with tipping bucket and eddy covariance

    NASA Astrophysics Data System (ADS)

    Hendricks Franssen, H. J.; Gebler, S.; Puetz, T.; Post, H.; Schmidt, M.; Vereecken, H.

    2014-12-01

    Although precipitation and actual evapotranspiration measurements have a long tradition, accurate estimates of precipitation (P) and actual evapotranspiration (ETa) remain a challenge. Our study compares actual evapotranspiration estimates acquired with the Eddy-Covariance (EC) method and ETa measurements by a set of six redundant weighable lysimeters for a managed grassland site at Rollesbroich (Eifel, Western Germany). The comparison of ETa measured by EC (accounting for energy balance deficit correction) and by lysimeters is hardly reported in literature and gains more insight into the performance of both techniques. The evaluation of ETa estimates by both methods for the year 2012 shows a good agreement with a total difference of ca. 4 %, which is mainly related to variations in grass height at the lysimeters and in the EC footprint. We also used the lysimeter records to estimate precipitation amounts in combination with the AWAT filter algorithm. The estimated precipitation volumes of the lysimeter measurements show significant differences compared to the precipitation data of the Hellman type tipping bucket rain gauge at the test site. For the entire year 2012 the lysimeter measurements exhibit a 16 % higher precipitation amount than the tipping bucket data. With help of an on-site video surveillance system the precipitation data of the lysimeters were investigated in more detail. It was found that the precipitation surplus in lysimeter records in part is related to the detection of rime and dew, which contributes 17 % to the yearly difference between both methods. We concluded that weighable lysimeter data can be used to simultaneously estimate precipitation and actual evapotranspiration in a reliable fashion. Furthermore, lysimeter allow a plausible detection of rime and dew in contrast to standard rain gauges.

  11. Noise Reduction Methods for Weighing Lysimeters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanical vibration of the grass and crop weighing lysimeters, located at the University of California West Side Field Research and Extension Station at Five Points, CA generated noise in lysimeter mass measurements and reduced the quality of evapotranspiration (ET) data. Two filtering methods for ...

  12. Teaching the Low Level Achiever.

    ERIC Educational Resources Information Center

    Salomone, Ronald E., Ed.

    1986-01-01

    Intended for teachers of the English language arts, the articles in this issue offer suggestions and techniques for teaching the low level achiever. Titles and authors of the articles are as follows: (1) "A Point to Ponder" (Rachel Martin); (2) "Tracking: A Self-Fulfilling Prophecy of Failure for the Low Level Achiever" (James Christopher Davis);…

  13. Field lysimeter studies for performance evaluation of grouted Hanford defense wastes

    SciTech Connect

    Last, G.V.; Serne, R.J.; LeGore, V.L.

    1995-02-01

    The Grout Waste Test Facility (GWTF) consisted of four large field lysimeters designed to test the leaching and migration rates of grout-solidified low-level radioactive wastes generated by Hanford Site operations. Each lysimeter was an 8-m-deep by 2-media closed-bottom caisson that was placed in the ground such that the uppermost rim remained just above grade. Two of these lysimeters were used; the other two remained empty. The two lysimeters that were used (A-1 and B-1) were backfilled with a two-layer soil profile representative of the proposed grout disposal site. The proposed grout disposal site (termed the Grout Treatment Facility Landfill) is located immediately east of the Hanford Site`s 200 East Area. This soil profile consisted of a coarse sand into which the grout waste forms were placed and covered by 4 m of a very fine sand. The A-1 lysimeter was backfilled in March 1985, with a grout-solidified phosphate/sulfate liquid waste from N Reactor decontamination and ion exchange resin regeneration. The B-1 lysimeter was backfilled in September 1985 and received a grout-solidified simulated cladding removal waste representative of waste generated from fuel reprocessing operations at the head end of the Plutonium Uranium Extraction (PUREX) plant. Routine monitoring and leachate collection activities were conducted for over three years, terminating in January 1989. Drainage was collected sporadically between January 1989 and December 1992. Decontamination and decommissioning of these lysimeters during the summer of 1994, confirmed the presence of a 15 to 20-cm-long hairline crack in one of the bottom plate welds. This report discusses the design and construction of the GWTF, presents the routine data collected from this facility through January 1989 and subsequent data collected sporadically between 1989 and 1993, and provides a brief discussion concerning preliminary interpretation of the results.

  14. Investigation of low-level laser therapy potentiality on proliferation and differentiation of human osteoblast-like cells in the absence/presence of osteogenic factors

    NASA Astrophysics Data System (ADS)

    Bloise, Nora; Ceccarelli, Gabriele; Minzioni, Paolo; Vercellino, Marco; Benedetti, Laura; De Angelis, Maria Gabriella Cusella; Imbriani, Marcello; Visai, Livia

    2013-12-01

    Several studies have shown that low-level laser irradiation (LLLI) has beneficial effects on bone regeneration. The objective of this study was to examine the in vitro effects of LLLI on proliferation and differentiation of a human osteoblast-like cell line (Saos-2 cell line). Cultured cells were exposed to different doses of LLLI with a semiconductor diode laser (659 nm 10 mW power output). The effects of laser on proliferation were assessed daily up to seven days of culture in cells irradiated once or for three consecutive days with laser doses of 1 or 3 J/cm2. The obtained results showed that laser stimulation enhances the proliferation potential of Saos-2 cells without changing their telomerase pattern or morphological characteristics. The effects on cell differentiation were assessed after three consecutive laser irradiation treatments in the presence or absence of osteo-inductive factors on day 14. Enhanced secretion of proteins specific for differentiation toward bone as well as calcium deposition and alkaline phosphatase activity were observed in irradiated cells cultured in a medium not supplemented with osteogenic factors. Taken together these findings indicate that laser treatment enhances the in vitro proliferation of Saos-2 cells, and also influences their osteogenic maturation, which suggest it is a helpful application for bone tissue regeneration.

  15. Selection of liquid-level monitoring method for the Oak Ridge National Laboratory inactive liquid low-level waste tanks, remedial investigation/feasibility study

    SciTech Connect

    Not Available

    1994-11-01

    Several of the inactive liquid low-level waste (LLLW) tanks at Oak Ridge National Laboratory contain residual wastes in liquid or solid (sludge) form or both. A plan of action has been developed to ensure that potential environmental impacts from the waste remaining in the inactive LLLW tank systems are minimized. This document describes the evaluation and selection of a methodology for monitoring the level of the liquid in inactive LLLW tanks. Criteria are established for comparison of existing level monitoring and leak testing methods; a preferred method is selected and a decision methodology for monitoring the level of the liquid in the tanks is presented for implementation. The methodology selected can be used to continuously monitor the tanks pending disposition of the wastes for treatment and disposal. Tanks that are empty, are scheduled to be emptied in the near future, or have liquid contents that are very low risk to the environment were not considered to be candidates for installing level monitoring. Tanks requiring new monitoring equipment were provided with conductivity probes; tanks with existing level monitoring instrumentation were not modified. The resulting data will be analyzed to determine inactive LLLW tank liquid level trends as a function of time.

  16. Prediction of waste leaching from solidified low-level radioactive waste

    NASA Astrophysics Data System (ADS)

    Tahboub, Alaeddin Borhan

    In 1983 a research program called Special Waste-Form Lysimeter Arid (SWLA) was initiated at Hanford Lysimeter testing facility near Richland, Washington to evaluate radionuclide release from solidified Low-Level Radioactive waste from underground burial facilities. The goal of this research is to help interpret experimental results from the Hanford site and formulate recommendations regarding source-term modeling for Low- Level waste forms. The specific objective is to test the diffusion source-term models based on ANS/ANSI 16.1 (ANS, 1986) laboratory leach test. The project uses the SWMS_2d model to predict the leaching of 137Cs, 90Sr, 60Co, and 3H radio nuclides from the waste form contained in Hanford lysimeters. Effective diffusion coefficients (De's) as measured by the above standard test were obtained from published literature for each nuclide. These De's together with the published soil properties and environmental conditions at the Hanford site are the model input. The source term modeling results are compared to the measured lysimeter data. Results showed that, the model is able to predict release of 3H. The model was not able to predict the release of 60Co from the waste form, which indicate that there are other processes rather than diffusion involved. The effective diffusion coefficient from ANS/ANSI 16.1 test can be used only for non reactive radionuclides like 3H (tritium).

  17. On-road and laboratory investigation of low-level PM emissions of a modern diesel particulate filter equipped diesel passenger car

    NASA Astrophysics Data System (ADS)

    Bergmann, Maik; Kirchner, Ulf; Vogt, Rainer; Benter, Thorsten

    Modern diesel particulate filter (DPF) systems are very effective in reducing particle emissions from diesel vehicles. In this work low-level particulate matter (PM) emissions from a DPF equipped EURO-4 diesel vehicle were studied in the emission test laboratory as well as during real-world chasing on a high-speed test track. Size and time resolved data obtained from an engine exhaust particle sizer (EEPS) and a condensation particle counter (CPC) are presented for both loaded and unloaded DPF condition. The corresponding time and size resolved emission factors were calculated for acceleration, deceleration, steady state driving and during DPF regeneration, and are compared with each other. In addition, the DPF efficiency of the tested vehicle was evaluated during the New European Driving Cycle (NEDC) by real time pre-/post-DPF measurements and was found to be 99.5% with respect to PM number concentration and 99.3% for PM mass, respectively. PM concentrations, which were measured at a distance of about 10 m behind the test car, ranged from 1 to 1.5 times background level when the vehicle was driven on the test track under normal acceleration conditions or at constant speeds below 100 kmh -1. Only during higher speeds and full load accelerations concentrations above 3 times background level could be observed. The corresponding tests in the emission laboratory confirmed these results. During DPF regeneration the total PM number emission of nucleation mode particles was 3-4 orders of magnitude higher compared to those emitted at the same speed without regeneration, while the level of the accumulation mode particles remained about the same. The majority of the particles emitted during DPF regeneration was found to be volatile, and is suggested to originate from accumulated sulfur compounds.

  18. Lysimeter Kleče Sanitation

    NASA Astrophysics Data System (ADS)

    Bracic Zeleznik, Branka; Cencur Curk, Barbara

    2010-05-01

    Ljubljana field aquifer is the main source of drinking water for Ljubljana. About 35% of the recharge area is used for agriculture, predominantly for intensive vegetable production therefore two lysimeters were built in 1991 at the area of the water pumping station Klece in order to study natural nitrate percolation through the unsaturated zone. The lysimeters consist of two concrete pipes (radius: 0,9 m, depth: 2,0 m), filled with autochthon soil, sandy (pebbles of 2-4 cm diameter) gravel and drainage material, each 50 cm thick. Both lysimeters are connected with control shaft. The mean porosity of the lysimeter is 22 %. At the bottom of the lysimeter outflow a drain pipe leads into adjacent control shaft where outflow is measured with tipping bucket. The measurements of percolating water indicated that the southern lysimeter is damaged, because the part of the percolating water is lost through the bottom of the container. This was the reason for the removal of the southern lysimeter and replacing it with hydro-lysimeter. The monolith of 2 m height and 1,1m diameter will be cut from sandy gravel sediments on the area of the water pumping station. Inside the monolith tensiometers, TDR probes and suction cups will be installed in three levels in depths of 50 cm, 100 cm and 150 cm. Additionally 2 tensiometers for temperature and tension in the depths 190 cm to transfer field matrix potential into the lysimeter will be installed. Long term observations of water balance and nitrate percolation are very important in order to assess trends in groundwater recharge and nitrate content. Measurements and monitoring of NO3-N in percolated water from non-fertilised area give information about nitrate natural background, which helps to determine the correct use of plant fertilizers and enables prompt reactions to negative trends on the groundwater quality.

  19. Design and Performance of a Large Modular Zero-Tension Lysimeter for in-situ Water Collection from Preferential Flow Paths

    NASA Astrophysics Data System (ADS)

    Peters, A.; Durner, W.

    2009-04-01

    We present a modular system that allows large zero-tension lysimeter plates to be installed under undisturbed soils. Such large sampling devices are necessary if preferential flow paths are present in soils. We conducted a numerical 2-D simulation study using homogeneous and heterogeneous soils to investigate the influence of the lysimeter on the water flow field in the soil, and thus the representativity of the measurements. The results show that the collection efficiency is highly dependent on the soil hydraulic functions, infiltration rate, and lysimeter size. If the soil is homogeneous, zero tension plate lysimeters can collect soil water only in soils with relatively small saturated hydraulic conductivity. The collection efficiency increases with increasing infiltration intensities and lysimeter sizes. In homogeneous soils with high saturated conductivities, even very large lysimeters (width 250 cm) are bypassed completely. Heterogeneity of soil hydraulic properties results in a network of flow channels that may either hit or bypass small sampling devices. For large lysimeters, it generally increases the collection efficiency. Tracer transport simulations with an inert solute in a heterogeneous medium show that the solute breakthrough into the lysimeter occurs slightly retarded as compared to the free soil. To test the performance of the plate lysimeter under real conditions, we conducted a field study with lysimeters of size 1.25 x 1.25 m. A tracer experiment with surface irrigation showed a collection efficiency of 45% and an almost immediate arrival of the tracers. This indicates that almost all collected water originated from preferential flow paths.

  20. Determining water and nitrogen balances for beneficial management practices using lysimeters at Wagna test site (Austria).

    PubMed

    Klammler, Gernot; Fank, Johann

    2014-11-15

    The shallow Murtal aquifer south of Graz, Austria, provides easily withdrawable groundwater, which is supplied as drinking water without any chemical treatment. The aquifer is also used intensively by agriculture. Common agricultural management practices are the main source for diffuse nitrogen leaching and high groundwater nitrate concentrations. To safeguard the coexisting use of these two important resources, lysimeters are operated at the agricultural test site Wagna, Austria, and the influence of two beneficial management practices--low nitrogen input and organic farming--on nitrogen leaching towards groundwater is investigated. The technical lysimeter design as presented here consists of: (1) high-resolution weighing cells, (2) a suction controlled lower boundary condition for sucking off seepage water, thus emulating undisturbed field conditions, (3) comparative soil temperature, water content and matrix potential measurements inside and outside the lysimeter at different depths, (4) an installation of the lysimeters directly into test plots and (5) a removable upper lysimeter ring enabling machinery soil tillage. Our results indicate that oasis effects or fringe effects of the lysimeter cylinder on unsaturated water flow did not occur. Another lysimeter cultivated with lawn is operated for observing grass-reference evapotranspiration, which resulted in good agreement with calculated grass-reference evapotranspiration according to the FAO-Penman-Monteith method. We conclude that lysimeters installed at Wagna test site did not show any fringe effects and, thus, are appropriate tools for measuring water balance elements and nitrogen leaching of arable and grass land at point scale. Furthermore, our results for the period of 2005 to 2011 show that beneficial management practices reduced nitrate leaching and, hence, may allow for a sustainable coexistence of drinking water supply and agriculture in the Murtal aquifer. PMID:24982000

  1. Investigation of Novel Electrode Materials for Electrochemically-Based Remediation of High- and Low-Level Mixed Wastes in the DOE Complex - Final Report

    SciTech Connect

    Lewis, N.S.; Anderson, M.

    2000-12-01

    New materials are investigated, based on degenerately-doped titanias, for use in the electrochemical degradation of organics and nitrogen-containing compounds in sites of concern to the DOE remediation effort. The data collected in this project appear to provide a rational approach for design of more efficient nanoporous electrodes. Also, osmium complexes appear to be promising candidates for further optimization in operating photo electrochemical cells for solar energy conversion applications.

  2. Environmental, Safety, and Health Plan for the remedial investigation of the liquid low-level waste tanks at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    SciTech Connect

    Not Available

    1991-09-01

    The Environmental, Safety, and Health (ES&H) Plan presents the concepts and methodologies to be used during the Oak Ridge National Laboratory (ORNL) RI/FS project to protect the health and safety of employees, the public, and the environment. The ES&H Plan acts as a management extension for ORNL and Energy Systems to direct and control implementation of the project ES&H program. This report describes the program philosophy, requirements, quality assurance measures, and methods for applying the ES&H program to individual task remedial investigations, project facilities, and other major tasks assigned to the project.

  3. Environmental, Safety, and Health Plan for the remedial investigation of the liquid low-level waste tanks at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    SciTech Connect

    DeFalco, S.; Kaiser, L. L.; May, L. E.

    1991-09-01

    The Environmental, Safety, and Health (ES H) Plan presents the concepts and methodologies to be used during the Oak Ridge National Laboratory (ORNL) RI/FS project to protect the health and safety of employees, the public, and the environment. The ES H Plan acts as a management extension for ORNL and Energy Systems to direct and control implementation of the project ES H program. This report describes the program philosophy, requirements, quality assurance measures, and methods for applying the ES H program to individual task remedial investigations, project facilities, and other major tasks assigned to the project.

  4. Can low-level ethanol exposure during pregnancy influence maternal care? An investigation using two strains of rat across two generations.

    PubMed

    Popoola, Daniel O; Borrow, Amanda P; Sanders, Julia E; Nizhnikov, Michael E; Cameron, Nicole M

    2015-09-01

    Gestational alcohol use is well documented as detrimental to both maternal and fetal health, producing an increase in offspring's tendency for alcoholism, as well as in behavioral and neuropsychological disorders. In both rodents and in humans, parental care can influence the development of offspring physiology and behavior. Animal studies that have investigated gestational alcohol use on parental care and/or their interaction mostly employ heavy alcohol use and single strains. This study aimed at investigating the effects of low gestational ethanol dose on parental behavior and its transgenerational transmission, with comparison between two rat strains. Pregnant Sprague Dawley (SD) and Long Evans (LE) progenitor dams (F0) received 1g/kg ethanol or water through gestational days 17-20 via gavage, or remained untreated in their home cages. At maturity, F1 female offspring were mated with males of the same strain and treatment and were left undisturbed through gestation. Maternal behavior was scored in both generations during the first six postnatal days. Arch-back nursing (ABN) was categorized as: 1, when the dam demonstrated minimal kyphosis; 2, when the dam demonstrated moderate kyphosis; and 3, when the dam displayed maximal kyphosis. Overall, SD showed greater amounts of ABN than LE dams and spent more time in contact with their pups. In the F0 generation, water and ethanol gavage increased ABN1 and contact with pups in SD, behaviors which decreased in treated LE. For ABN2, ethanol-treated SD dams showed more ABN2 than water-treated dams, with no effect of treatment on LE animals. In the F1 generation, prenatal exposure affected retrieval. Transgenerational transmission of LG was observed only in the untreated LE group. Strain-specific differences in maternal behavior were also observed. This study provides evidence that gestational gavage can influence maternal behavior in a strain-specific manner. Our results also suggest that the experimental procedure during

  5. Investigation of novel electrode materials for electrochemically based remediation of high and low-level mixed wastes in the DOE complex. 1997 annual progress report

    SciTech Connect

    Anderson, M.A.; Lewis, N.S.

    1997-01-01

    'This work is focused on the preparation of novel electrode materials for the degradation of toxic wastes in the DOE complex. One of the goals of this work is to characterize whether it is possible to use controlled doping of TiO{sub 2} with species such as Nb in order to create new electrode materials that will facilitate the destruction of undesirable organics and inorganics, without light and instead only with an applied potential, in the waste tanks at the DOE sites. In the first part of this project, the authors have therefore spent an extensive amount of effort characterizing, as a baseline, the chemical and electrochemical behavior of TiO{sub 2} itself, so that they can make robust comparisons to the behavior of the Nb-doped systems in subsequent work on this project. The preparation of these electrode films is being performed by Marc Anderson at Wisconsin, who is preparing a number of different stoichiometries, grain sizes, etc. for investigation of their electrochemical properties by the Lewis group at Caltech. First they report on the progress of the electrode preparation work, and then they describe progress on the electrochemical work.'

  6. An overview of the geochemical code MINTEQ: Applications to performance assessment for low-level wastes

    SciTech Connect

    Peterson, S.R.; Opitz, B.E.; Graham, M.J.; Eary, L.E.

    1987-03-01

    The MINTEQ geochemical computer code, developed at the Pacific Northwest Laboratory (PNL), integrates many of the capabilities of its two immediate predecessors, MINEQL and WATEQ3. The MINTEQ code will be used in the Special Waste Form Lysimeters-Arid program to perform the calculations necessary to simulate (model) the contact of low-level waste solutions with heterogeneous sediments of the interaction of ground water with solidified low-level wastes. The code can calculate ion speciation/solubilitya, adsorption, oxidation-reduction, gas phase equilibria, and precipitation/dissolution of solid phases. Under the Special Waste Form Lysimeters-Arid program, the composition of effluents (leachates) from column and batch experiments, using laboratory-scale waste forms, will be used to develop a geochemical model of the interaction of ground water with commercial, solidified low-level wastes. The wastes being evaluated include power-reactor waste streams that have been solidified in cement, vinyl ester-styrene, and bitumen. The thermodynamic database for the code was upgraded preparatory to performing the geochemical modeling. Thermodynamic data for solid phases and aqueous species containing Sb, Ce, Cs, or Co were added to the MINTEQ database. The need to add these data was identified from the characterization of the waste streams. The geochemical model developed from the laboratory data will then be applied to predict the release from a field-lysimeter facility that contains full-scale waste samples. The contaminant concentrations migrating from the waste forms predicted using MINTEQ will be compared to the long-term lysimeter data. This comparison will constitute a partial field validation of the geochemical model.

  7. Long-term lysimeter experiment to analyze the influence of the climate change on matter fluxes

    NASA Astrophysics Data System (ADS)

    Pütz, Thomas; Groh, Jannis; Wollschläger, Ute; Gerke, Horst; Priesack, Eckart; Kiese, Ralf; Borg, Erik; Vereecken, Harry

    2015-04-01

    Based on the TERENO SoilCan infrastructure, a long-term large-scale experiment was designed to study the effects of climate change on terrestrial systems. The water and matter fluxes in soil are the main focuses of SoilCan. In the frame of SoilCan, fully automated lysimeter systems were installed on several highly equipped experimental field sites of the TERENO-observatories and the relevant status variables of each ecosystem were monitored (e.g. climate, hydrology, biosphere-atmosphere exchange, biodiversity, etc.). In total, 90 lysimeters (1.5 m depth, 1m2 surface) were filled with soil monoliths at the four TERENO-observatories and were instrumented with TDRs, tensiometers, temperature sensors, soil heat flux plates, and CO2 sensors. For the controlling of the lower boundary condition, suction candle rakes were installed into the lysimeter bottoms. In combination with bi-directional pumps and tanks, the water content of the lysimeters was adjusted to the surrounded original field sites. To simulate the expected climate change, 48 lysimeters were transferred along temperature and rainfall gradients within the respective observatories and between the observatories, based on the principle 'Space for Time'. In case of the "Rur" observatory, three intensively instrumented field sites ("Wüstebach", "Rollesbroich" und "Selhausen") were equipped with lysimeter stations. These three field sites include different land uses, "Wüstebach" as a forest site, "Rollesbroich" as a grassland and "Selhausen" as an arable site. In order to standardize the agronomic management, the crop rotation at the arable lysimeters comprised winter wheat - winter rye - winter barley - oats. For investigation of the matter flux, soil solutions and leachates were regularly sampled. The water balances and the dynamics of the carbon and nitrogen fluxes in the first two years of the experiment will be presented.

  8. The effects of aging on compressive strength of low-level radioactive waste form samples

    SciTech Connect

    McConnell, J.W. Jr.; Neilson, R.M. Jr.

    1996-06-01

    The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the US Nuclear Regulatory Commission (NRC), is (a) studying the degradation effects in organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified ion-exchange resins, (c) obtaining performance information on solidified ion-exchange resins in a disposal environment, and (d) determining the condition of liners used to dispose ion-exchange resins. Compressive tests were performed periodically over a 12-year period as part of the Technical Position testing. Results of that compressive testing are presented and discussed. During the study, both portland type I-II cement and Dow vinyl ester-styrene waste form samples were tested. This testing was designed to examine the effects of aging caused by self-irradiation on the compressive strength of the waste forms. Also presented is a brief summary of the results of waste form characterization, which has been conducted in 1986, using tests recommended in the Technical Position on Waste Form. The aging test results are compared to the results of those earlier tests. 14 refs., 52 figs., 5 tabs.

  9. Geochemical analysis of leachates from cement/low-level radioactive waste/soil systems

    SciTech Connect

    Criscenti, L.J.; Serne, R.J.

    1988-09-01

    Laboratory experiments were conducted as part of the Special Waste Form Lysimeters/endash/Arid Program. These experiments were conducted to investigate the performance of solidified low-level nuclear waste in a typical arid, near-surface disposal site, and to evaluate the ability of laboratory tests to predict leaching in actual field conditions. Batch leaching, soil adsorption column, and soil/waste form column experiments were conducted using Portland III cement waste forms containing boiling-water reactor evaporator concentrate and ion-exchange resin waste. In order to understand the reaction chemistry of the cement waste form/soil/ground-water system, the compositions of the leachates from the laboratory experiments were studied with the aid of the MINTEQ ion speciation/solubility and mass transfer computer code. The purpose of this report is to describe the changes in leachate composition that occur during the course of the experiments, to discuss the geochemical modeling results, and to explore the factors controlling the major element chemistry of these leachates. 18 refs., 84 figs., 14 tabs.

  10. Codisposal of diminimus levels of low-level radioactive waste and sanitary waste: Final report

    SciTech Connect

    Chian, E.S.K.; Ghosh, S.B.; Kahn, B.; Giabbai, M.; Pohland, F.G.

    1986-02-01

    Codisposal of low-level radioactive waste (LLRW) with municipal refuse was investigated in two pilot-scale controlled concrete lysimeters; 3.05 m x 3.05 m x 4.28 m that were lined with 0.762 mm (30-mil) HDA Gundline liner, elastomeric polyolefin alloy based high density polyethylene, and had provisions for leachate collection and recirculation. Shredded municipal refuse was placed within the landfills and spiked with radionuclides (Co-58, Sr-85, and Ce-141) at a level of 28 nCi/gm to simulate codisposal of LLRW with municipal refuse. Water was added to simulate normal rainfall events; the extent to which radionuclides and organics were leached from both landfills was recorded. To compare the effect of leachate recirculation on the indicator parameters, leachate recycle was practiced in one of the landfills, while the other was operated as a single-pass system. Analyses on leachate samples, collected from both landfills, included detection of Co-58, Sr-85, and Ce-141 along with pH, ORP, conductivity, total alkalinity, COD, BOD/sub 5/, TOC, volatile fatty acids (acetic, propionic, isobutyric, butyric, and valeric), sulfide, chloride, iron, manganese, zinc, nickel, and cobalt. 113 refs., 47 figs., 23 tabs.

  11. Behavior of water balance components at sites with shallow groundwater tables: Possibilities and limitations of their simulation using different types of groundwater lysimeters

    NASA Astrophysics Data System (ADS)

    Dietrich, Ottfried; Fahle, Marcus

    2015-04-01

    Groundwater lysimeters are a special type of lysimeter that can provide valuable insights into processes occurring at sites with shallow groundwater tables. Typically, water balance simulations for such sites using hydrological models are complicated by the permanently changing directions of the water fluxes due to percolation and capillary rise and the complex hydrological conditions. Problems also arise when trying to imitate such conditions correctly in a lysimeter. The biggest challenge is to realistically simulate the lower boundary condition, which has a pronounced impact on most of the hydrological variables, especially when considering time scales shorter than one day. Historically, groundwater levels in soil monoliths of groundwater lysimeters were controlled by so-called Mariotte bottles (type 1). Even nowadays, most groundwater lysimeters use such systems. From a technical standpoint, the solution is reliable and simple to operate and maintain. Nevertheless, the accuracy of Mariotte bottles (type 1) is limited when simulatingnatural shallow groundwater table conditions which are characterized by fluctuations on a short time scale. Today's lysimeters are able to simulate measured groundwater levels with higher accuracy, even for short time steps (type 2). However, conditions in the lysimeter and the place where the reference groundwater level is measured have to be consistent in order to get reliable results. Problems also arise if the behavior of the groundwater level itself is the aim of the investigation as the groundwater level has to be pre-defined, i.e. it is the control value. A new approach regulates the lower boundary condition by controlling the in- and outflows of the lysimeter (type 3). This enlarges the field of possible applications of groundwater lysimeters, especially with respect to simulations of natural site conditions and short time scales. The presentation compares the performance of different types of groundwater lysimeters with

  12. Leaching studies of low-level radioactive waste forms

    SciTech Connect

    Dayal, R.; Arora, H.; Milian, L.; Clinton, J.

    1985-01-01

    A research program has been underway at the Brookhaven National Laboratory to investigate the release of radionuclides from low-level waste forms under laboratory conditions. This paper describes the leaching behavior of Cs-137 from two major low-level waste streams, that is, ion exchange bead resin and boric acid concentrate, solidified in Portland cement. The resultant leach data are employed to evaluate and predict the release behavior of Cs-137 from low-level waste forms under field burial conditions.

  13. Whole Genome Sequencing Investigation of a Tuberculosis Outbreak in Port-au-Prince, Haiti Caused by a Strain with a "Low-Level" rpoB Mutation L511P - Insights into a Mechanism of Resistance Escalation.

    PubMed

    Ocheretina, Oksana; Shen, Lishuang; Escuyer, Vincent E; Mabou, Marie-Marcelle; Royal-Mardi, Gertrude; Collins, Sean E; Pape, Jean W; Fitzgerald, Daniel W

    2015-01-01

    The World Health Organization recommends diagnosing Multidrug-Resistant Tuberculosis (MDR-TB) in high burden countries by detection of mutations in Rifampin (RIF) Resistance Determining Region of Mycobacterium tuberculosis rpoB gene with rapid molecular tests GeneXpert MTB/RIF and Hain MTBDRplus. Such mutations are found in >95% of Mycobacterium tuberculosis strains resistant to RIF by conventional culture-based drug susceptibility testing (DST). However routine diagnostic screening with molecular tests uncovered specific "low level" rpoB mutations conferring resistance to RIF below the critical concentration of 1 μg/ml in some phenotypically susceptible strains. Cases with discrepant phenotypic (susceptible) and genotypic (resistant) results for resistance to RIF account for at least 10% of resistant diagnoses by molecular tests and urgently require new guidelines to inform therapeutic decision making. Eight strains with a "low level" rpoB mutation L511P were isolated by GHESKIO laboratory between 2008 and 2012 from 6 HIV-negative and 2 HIV-positive patients during routine molecular testing. Five isolates with a single L511P mutation and two isolates with double mutation L511P&M515T had MICs for RIF between 0.125 and 0.5 μg/ml and tested susceptible in culture-based DST. The eighth isolate carried a double mutation L511P&D516C and was phenotypically resistant to RIF. All eight strains shared the same spoligotype SIT 53 commonly found in Haiti but classic epidemiological investigation failed to uncover direct contacts between the patients. Whole Genome Sequencing (WGS) revealed that L511P cluster isolates resulted from a clonal expansion of an ancestral strain resistant to Isoniazid and to a very low level of RIF. Under the selective pressure of RIF-based therapy the strain acquired mutation in the M306 codon of embB followed by secondary mutations in rpoB and escalation of resistance level. This scenario highlights the importance of subcritical resistance to RIF

  14. Upscaling of lysimeter measurements to regional groundwater nitrate distribution

    NASA Astrophysics Data System (ADS)

    Klammler, Gernot; Fank, Johann; Kupfersberger, Hans; Rock, Gerhard

    2015-04-01

    For many European countries nitrate leaching from the soil zone into the aquifer due to surplus application of mineral fertilizer and animal manure by farmers constitutes the most important threat to groundwater quality. This is a diffuse pollution situation and measures to change agricultural production have to be investigated at the aquifer scale to safeguard drinking water supply from shallow groundwater resources Lysimeters are state-of-the-art measurements for water and solute fluxes through the unsaturated zone towards groundwater at the point scale, but due to regional heterogeneities (especially concerning soil conditions) lysimeters cannot provide aquifer-wide groundwater recharge and solute leaching. Thus, in this work the numerical simulation model SIMWASER/STOTRASIM (Stenitzer, 1988; Feichtinger, 1998) for quantifying groundwater recharge and nitrate leaching at aquifer scale is applied. Nevertheless, according to Groenendijk et al. (2014) a model calibration by means of lysimeter measurements is essential, since uncalibrated models are generally far from acceptable. Thus, a lysimeter provides the basis for the parameterization of numerical simulation models. To quantify also the impact on regional nitrate distribution in the groundwater, we couple the unsaturated zone model SIMWASER/STOTRASIM with the saturated groundwater flow and solute transport model FELOW (Diersch, 2009) sequentially. In principal, the problem could be solved by the 3 dimensional equation describing variable saturated groundwater flow and solute transport. However, this is computationally prohibitive due to the temporal and spatial scope of the task, particularly in the framework of running numerous simulations to compromise between conflicting interests (i.e. good groundwater status and high agricultural yield). To account for the unknown regional distribution of crops grown and amount, timing and kind of fertilizers used a stochastic tool (Klammler et al, 2011) is developed that

  15. Packaged low-level waste verification system

    SciTech Connect

    Tuite, K.; Winberg, M.R.; McIsaac, C.V.

    1995-12-31

    The Department of Energy through the National Low-Level Waste Management Program and WMG Inc. have entered into a joint development effort to design, build, and demonstrate the Packaged Low-Level Waste Verification System. Currently, states and low-level radioactive waste disposal site operators have no method to independently verify the radionuclide content of packaged low-level waste that arrives at disposal sites for disposition. At this time, the disposal site relies on the low-level waste generator shipping manifests and accompanying records to ensure that low-level waste received meets the site`s waste acceptance criteria. The subject invention provides the equipment, software, and methods to enable the independent verification of low-level waste shipping records to ensure that the site`s waste acceptance criteria are being met. The objective of the prototype system is to demonstrate a mobile system capable of independently verifying the content of packaged low-level waste.

  16. Low level tank waste disposal study

    SciTech Connect

    Mullally, J.A.

    1994-09-29

    Westinghouse Hanford Company (WHC) contracted a team consisting of Los Alamos Technical Associates (LATA), British Nuclear Fuel Laboratories (BNFL), Southwest Research Institute (SwRI), and TRW through the Tank Waste Remediation System (TWRS) Technical Support Contract to conduct a study on several areas concerning vitrification and disposal of low-level-waste (LLW). The purpose of the study was to investigate how several parameters could be specified to achieve full compliance with regulations. The most restrictive regulation governing this disposal activity is the National Primary Drinking Water Act which sets the limits of exposure to 4 mrem per year for a person drinking two liters of ground water daily. To fully comply, this constraint would be met independently of the passage of time. In addition, another key factor in the investigation was the capability to retrieve the disposed waste during the first 50 years as specified in Department of Energy (DOE) Order 5820.2A. The objective of the project was to develop a strategy for effective long-term disposal of the low-level waste at the Hanford site.

  17. Chemical characterization, leach, and adsorption studies of solidified low-level wastes

    SciTech Connect

    Walter, M.B.; Serne, R.J.; Jones, T.L.; McLaurine, S.B.

    1986-12-01

    Laboratory and field leaching experiments are beig conducted by Pacific Northwest Laboratory (PNL) to investigate the performance of solidified low-level nuclear waste in a typical, arid, near-surface disposal site. Under PNL's Special Waste Form Lysimeters-Arid Program, a field test facility was constructed to monitor the leaching of commercial solidified waste. Laboratory experiments were conducted to investigate the leaching and adsorption characteristics of the waste forms in contact with soil. Liquid radioactive wastes solidified in cement, vinyl ester-styrene, and bitumen were obtained from commercial boiling water and pressurized water reactors, and buried in a field leaching facility on the Hanford site in southeastern Washington State. Batch leaching, soil column adsorption, and soil/waste form column experiments were conducted in the laboratory, using small-scale cement waste forms and Hanford site ground water. The purpose of these experiments is to evaluate the ability of laboratory leaching tests to predict leaching under actual field conditions and to determine which mechanisms (i.e., diffusion, solubility, adsorption) actually control the concentration of radionuclides in the soil surrounding the waste form. Chemical and radionuclide analyses performed on samples collected from the field and laboratory experiments indicate strong adsorption of /sup 134,137/Cs and /sup 85/Sr onto the Hanford site sediment. Small amounts of /sup 60/Co are leached from the waste forms as very mobile species. Some /sup 60/Co migrated through the soil at the same rate as water. Chemical constituents present in the reactor waste streams also found at elevated levels in the field and laboratory leachates include sodium, sulfate, magnesium, and nitrate. Plausible solid phases that could be controlling some of the chemical and radionuclide concentrations in the leachate were identified using the MINTEQ geochemical computer code.

  18. Low level moisture from VAS

    NASA Technical Reports Server (NTRS)

    Hayden, C. M.

    1980-01-01

    Previous research and current opinion are too pessimistic concerning the capability of defining moisture fields from satellite measurements. The TIROS-N sounder is a close analogue to what will fly on GEOS-D and can be used to investigate the probable capability of VAS. Basically, there are three frequencies applied to sensing moisture in the troposphere. The ability of these three measurements to define the moisture pattern is assessed. It is certainly true that one cannot achieve the detail available with a radiosonde hygristor. Sharp discontinuities cannot be sensed by a passive sounder, especially since the measurement tends to "saturate" with the first moisture layer encountered. However, the satellite measurements demonstrate a high degree of skill in defining the horizontal gradient. Moisture "tongues" and "dry lines" are readily delineated with some, perhaps two layers, of vertical definition. These attributes allow both the calculation of important advective quantities as well as (in concert with the temperature sounding) a gross definition of the vertical stability. The skill is demonstrably commensurate with subsynoptic forecast models and perhaps even to regional scale models.

  19. Low-level waste program technical strategy

    SciTech Connect

    Bledsoe, K.W.

    1994-10-01

    The Low-Level Waste Technical Strategy document describes the mechanisms which the Low-Level Waste Program Office plans to implement to achieve its mission. The mission is to manage the receipt, immobilization, packaging, storage/disposal and RCRA closure (of the site) of the low-level Hanford waste (pretreated tank wastes) in an environmentally sound, safe and cost-effective manner. The primary objective of the TWRS Low-level waste Program office is to vitrify the LLW fraction of the tank waste and dispose of it onsite.

  20. Impact of agricultural management practices on DOC leaching - results of a long-term lysimeter study

    NASA Astrophysics Data System (ADS)

    Wagner, A.; Ollesch, G.; Seeger, J.; Meißner, R.; Rode, M.

    2009-04-01

    Dissolved organic carbon (DOC) fluxes are recently increasing in surface waters of humid climate regions. Due to its substantial importance for leaching processes, aquatic foodwebs, and drinking water purification a better understanding of sources and pathways of DOC is needed. Therefore this study aims to analyse and simulate DOC fluxes in agricultural ecosystems with selected crop rotations. A data set of 24 lysimeters of the UFZ Lysimeter station at Falkenberg (Saxony-Anhalt) covering nine years of DOC investigation has been selected and examined. The data set covers a wide range of climatic conditions with deviating management practices for grasslands and agricultural crop rotations. The monthly DOC concentrations assessed in the leached water range from 2.4 to 34.1 mg /l. DOC concentrations depend on temperature, precipitation and discharge. The type of crop grown on the lysimeter is an important trigger for DOC leaching - especially lysimeters used as pasture, or planted with rape and carrots exhibit high DOC concentrations. Management practices and fertilizer application modify the leaching of DOC and offer potentials to reduce DOC losses. The results form the basis of further process simulation studies and upscaling of the results to the small catchment scale.

  1. Characterizing soil water dynamics on steep hillslopes from long-term lysimeter data

    NASA Astrophysics Data System (ADS)

    Augenstein, Michael; Goeppert, Nadine; Goldscheider, Nico

    2015-10-01

    Understanding soil water dynamics on hillslopes is of crucial importance to the prediction of floods and other hydrological events in mountainous catchments, to the identification of natural vegetation patterns, and to the optimization of agricultural land use. In principle, such information can be obtained from lysimeters, but most experimental lysimeter facilities have been installed on flat terrain. This study presents a long-term and high-resolution investigation of soil moisture, surface and subsurface flow using three large-scale lysimeters on a slope with 23.5° inclination on a landfill site in Karlsruhe, Germany. Data from a 10-year observation period were evaluated for this study, including weekly soil moisture data obtained by neutron probes, continuous discharge data from the land surface and several layers within the soil zone, and hydrometeorological data from a climate station. The results reveal (i) clear temporal and spatial patterns of soil moisture variations down to a depth of 250 cm, (ii) substantially higher discharge and faster percolation rates in the lower part of the lysimeter field, indicating significant downhill flow at various depths within the soil profile, (iii) characteristic threshold values for flow processes in the soil, associated with a hysteresis effect between soil moisture and flow processes. These results can be used as a basis of improved numerical models for the simulation of floods, soil moisture distributions, and vegetation patterns.

  2. Wireless lysimeters for real-time online soil water monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Identification of nitrate-nitrogen (NO3-N) in drainage water allows accessing the effectiveness of water quality management. A passive capillary wick-type lysimeter (PCAPs) was used to monitor water flux and NO3-N leached below the root zone under an irrigated cropping system. Wireless lysimeters we...

  3. Field Lysimeter Test Facility: Protective barrier test results (FY 1990, the third year)

    SciTech Connect

    Campbell, M.D.; Gee, G.W.

    1990-11-01

    The Field Lysimeter Test Facility (FLTF) was constructed to test protective barriers for isolating low-level radioactive and hazardous wastes from the biosphere. Protective barriers are specially configured earth materials placed over near-surface wastes to prevent intrusion of water, plants, and animals. Low-level radioactive waste is stored in near-surface repositories at the Hanford Site and can be transported into the biosphere by water, plants, and animals. The purpose of the FLTF is to measure water balance within barriers as precipitation is partitioned to evaporation (including transpiration), storage, and drainage. Runoff was prevented by raised edges on the lysimeters. Water balance in protective barriers depends on the water-holding capacity of the soil, the gradient of a potential, and the conductivity of the underlying capillary barrier. Current barrier design uses soil with a high water storage capacity and a capillary barrier underlying the soil to increase its water storage capacity. This increased storage capacity is to hold water, which would normally drain, near the the surface where evaporation can cycle it back to the atmosphere. 7 refs., 23 figs., 5 tabs.

  4. Improving the performance of lysimeters with thermal imaging

    NASA Astrophysics Data System (ADS)

    Voortman, Bernard; Bartholomeus, Ruud; Witte, Jan-Philip

    2014-05-01

    Precision weighing lysimeters generate data of evapotranspiration (ET) at a high resolution in the order of 0.01 to 0.05 mm. Though this resolution is often reported as the accuracy of the lysimeter, it is in fact the precision of the weighing device. The accuracy of a lysimeter is heavily dependent on its ability to duplicate environmental conditions of its surroundings. In general, measurement errors will decrease with increasing lysimeter dimension, primarily because a larger part of the lysimeter is unaffected by its boundaries and because heterogeneities in soil hydraulic properties and micro-climate are more averaged out. However, the cost of large lysimeters make them unattractive and scientists often choose for more economical solutions, optimizing between lysimeter dimensions and costs. Instead of investing in large lysimeters or putting effort in duplicating environmental conditions, we invested in monitoring the surface temperature of zero tension lysimeters with a thermal infrared camera to detect deviations in ET. In such a system, measurement errors caused by deviations in moisture content can be compensated, without the struggle of controlling the lysimeter moisture content with pressure plates and vacuum pumps or preventing wall flow. Other advantages of using thermal imaging are that (i) measurements of ET can be extrapolated to much larger areas than the surface area of most conventional lysimeters, and (ii) ET can be split into soil evaporation and transpiration, which allows us to study the effects of the vegetation structure on the water balance. Several experiments were performed to estimate differences in ET between lysimeters based on the radiometric surface temperature. Two simple methods, 1) linear scaling and 2) a comparison of the surface energy balance were applied to translate differences in surface temperature to differences in ET. We examined the application of both methods on bare sand, moss and grass. We show that the performance

  5. Mixed and Low-Level Treatment Facility Project

    SciTech Connect

    Not Available

    1992-04-01

    This appendix contains the mixed and low-level waste engineering design files (EDFS) documenting each low-level and mixed waste stream investigated during preengineering studies for Mixed and Low-Level Waste Treatment Facility Project. The EDFs provide background information on mixed and low-level waste generated at the Idaho National Engineering Laboratory. They identify, characterize, and provide treatment strategies for the waste streams. Mixed waste is waste containing both radioactive and hazardous components as defined by the Atomic Energy Act and the Resource Conservation and Recovery Act, respectively. Low-level waste is waste that contains radioactivity and is not classified as high-level waste, transuranic waste, spent nuclear fuel, or 11e(2) byproduct material as defined by DOE 5820.2A. Test specimens of fissionable material irradiated for research and development only, and not for the production of power or plutonium, may be classified as low-level waste, provided the concentration of transuranic is less than 100 nCi/g. This appendix is a tool that clarifies presentation format for the EDFS. The EDFs contain waste stream characterization data and potential treatment strategies that will facilitate system tradeoff studies and conceptual design development. A total of 43 mixed waste and 55 low-level waste EDFs are provided.

  6. Variably-saturated flow in large weighing lysimeters under dry conditions: inverse and predictive modeling

    NASA Astrophysics Data System (ADS)

    Iden, Sascha; Reineke, Daniela; Koonce, Jeremy; Berli, Markus; Durner, Wolfgang

    2015-04-01

    A reliable quantification of the soil water balance in semi-arid regions requires an accurate determination of bare soil evaporation. Modeling of soil water movement in relatively dry soils and the quantitative prediction of evaporation rates and groundwater recharge pose considerable challenges in these regions. Actual evaporation from dry soil cannot be predicted without detailed knowledge of the complex interplay between liquid, vapor and heat flow and soil hydraulic properties exert a strong influence on evaporation rates during stage-two evaporation. We have analyzed data from the SEPHAS lysimeter facility in Boulder City (NV) which was installed to investigate the near-surface processes of water and energy exchange in desert environments. The scientific instrumentation consists of 152 sensors per Lysimeter which measured soil temperature, soil water content, and soil water potential. Data from three weighing lysimeters (3 m long, surface area 4 m2) were used to identifiy effective soil hydraulic properties of the disturbed soil monoliths by inverse modeling with the Richards equation assuming isothermal flow conditions. Results indicate that the observed soil water content in 8 different soil depths can be well matched for all three lysimeters and that the effective soil hydraulic properties of the three lysimeters agree well. These results could only be obtained with a flexible model of the soil hydraulic properties which guaranteed physical plausibility of water retention towards complete dryness and accounted for capillary, film and isothermal vapor flow. Conversely, flow models using traditional parameterizations of the soil hydraulic properties were not able to match the observed evaporation fluxes and water contents. After identifying the system properties by inverse modeling, we checked the possibility to forecast evaporation rates by running a fully coupled water, heat and vapor flow model which solved the energy balance of the soil surface. In these

  7. Coupled pot and lysimeter experiments assessing plant performance in microbially assisted phytoremediation.

    PubMed

    Nicoară, Andrei; Neagoe, Aurora; Stancu, Paula; de Giudici, Giovanni; Langella, Francesca; Sprocati, Anna Rosa; Iordache, Virgil; Kothe, Erika

    2014-01-01

    We performed an experiment at pot scale to assess the effect of plant growth-promoting bacteria (PGPB) on the development of five plant species grown on a tailing dam substrate. None of the species even germinated on inoculated unamended tailing material, prompting use of compost amendment. The effect of inoculation on the amended material was to increase soil respiration, and promote elements immobilisation at plant root surface. This was associated with a decrease in the concentrations of elements in the leaching water and an increase of plant biomass, statistically significant in the case of two species: Agrostis capillaris and Festuca rubra. The experiment was repeated at lysimeter scale with the species showing the best development at pot scale, A. capillaris, and the significant total biomass increase as a result of inoculation was confirmed. The patterns of element distribution in plants also changed (the concentrations of metals in the roots of A. capillaris and F. rubra significantly decreased in inoculated treatments, while phosphorus concentration significantly increased in roots of A. capillaris in inoculated treatment at lysimeter scale). Measured variables for plant oxidative stress did not change after inoculations. There were differences of A. capillaris plant-soil system response between experimental scales as a result of different substrate column structure and plant age at the sampling moment. Soil respiration was significantly larger at lysimeter scale than at pot scale. Leachate concentrations of As, Mn and Ni had significantly larger concentrations at lysimeter scale than at pot scale, while Zn concentrations were significantly smaller. Concentrations of several metals were significantly smaller in A. capillaris at lysimeter scale than at pot scale. From an applied perspective, a system A. capillaris-compost-PGPB selected from the rhizosphere of the tailing dam native plants can be an option for the phytostabilisation of tailing dams. Results

  8. Low-level waste forum meeting reports

    SciTech Connect

    Sternwheeler, W.D.E.

    1992-12-31

    This paper provides highlights from the 1992 winter meeting of the Low Level Radioactive Wastes Forum. Topics of discussion included: legal information; state and compact reports; freedom of information requests; and storage.

  9. Low-level waste forum meeting reports

    SciTech Connect

    1992-12-31

    This report provides highlights from the 1992 fall meeting of the Low LEvel Radioactive Waste Forum. Topics included: disposal options after 1992; interregional agreements; management alternatives; policy; and storage.

  10. Using lysimeters to test the Penman Monteith actual evapotranspiration.

    NASA Astrophysics Data System (ADS)

    Ben Asher, Jiftah; Volinski, Roman; Zilberman, Arkadi; Bar Yosef, Beni; Silber, Avner

    2015-04-01

    Differences in actual transpiration (ETa) of banana plants were quantified in a lysimeter experiment. ETA was computed using instantaneous data from two weighing lysimeters and compared to PM (Penman-Monteith) model for ETa. Two critical problems were faced in this test. A) Estimating canopy and aerodynamic resistances ("rc" and "ra" respectively ) and B) converting the lysimeter changes in water volume ( LYv cm3 ) to ETa length units ( cm ). The two unknowns " rc" and "ra" were obtained from continuous measurements of the differences between canopy and air temperature (Tc - Ta). This difference was established by means of the infrared thermometry which was followed by numerical and analytical calculation of ETa using the modification suggested by R. Jackson to the PM model. The conversion of lysimeter volumetric units (LYv) to ETa length units was derived from the slope of cumulative LYv/ETa. This relationship was significantly linear (r2=0.97and 0.98.). Its slope was interpreted as "evaporating leaf area" which accounted for 1.8E4 cm2 in lysimeter 1 and 2.3E4 cm2.in lysimeter 2 . The comparison between LYv and PM model was acceptable even under very low ETa. The average of two lysimeters was 1.1mm/day (1.4 mm/day , LYv 1 and 0.8 LYv 2) while ETa calculated on the basis of PM model was 1.2 mm/day. It was concluded that although lysimeters are most accurate systems to measure ETa one of its disadvantages ( beside the high cost) is the volumetric output that in many cases should be supported by a one dimensional energy balance system. The PM model was found to be a reliable complementary tool to convert lysimeters volumetric output into conventional length units of ETa.

  11. Characteristics of low-level smokers.

    PubMed

    Hyland, Andrew; Rezaishiraz, Hamed; Bauer, Joseph; Giovino, Gary A; Cummings, K Michael

    2005-06-01

    Average daily cigarette consumption has decreased, and some evidence suggests that the rate of "some day" smoking has increased; however, relatively little is known about low-level smokers. The present analysis describes and compares low-level versus heavier smokers, using cross-sectional and longitudinal data. Data from the Community Intervention Trial for Smoking Cessation (COMMIT) were used in this analysis. Population-based cross-sectional tobacco use telephone surveys were performed in 22 North American communities in 1988 and 1993, and the prevalence and characteristics of low-level smoking and reasons for quitting are reported from the 1993 prevalence survey. In addition, a cohort of 6,603 smokers was identified in 1988 and interviewed again in 1993 and 2001 to assess patterns of low-level smoking over time and its association with smoking cessation. In 1988, 7.6% were low-level smokers; in 1993, 10.7% were low-level smokers. Compared with heavier smokers, low-level smokers were more likely to be female, older, not married, Black or Hispanic; to have a 4-year college degree; to have no other adult smokers in the household; and to wait longer in the day to have their first cigarette. Low-level smokers also were less likely to report trying to quit because of the expense of smoking or physician advice to quit. They were more likely to try to quit because of trying to set a good example; concern for second-hand smoke; and factors such as bad breath, smell, or the taste of smoking. Those who smoked full-priced premium brands and who worked in a completely smoke-free worksite were more likely to be low-level smokers. Compared with heavier smokers, low-level smokers had similar rates of making a future quit attempt, lower use rates of nicotine replacement therapy, and higher cessation rates. Low-level smokers may be a growing segment of the smoker population and have different characteristics, health risks, and intervention needs compared with their heavier

  12. Low-level-waste-form criteria

    SciTech Connect

    Barletta, R.E.; Davis, R.E.

    1982-01-01

    Efforts in five areas are reported: technical considerations for a high-integrity container for resin wastes; permissible radionuclide loadings for organic ion exchange resin wastes; technical factors affecting low-level waste form acceptance requirements of the proposed 10 CFR 61 and draft BTP; modeling of groundwater transport; and analysis of soils from low-level waste disposal sites (Barnwell, Hanford, and Sheffield). (DLC)

  13. Polyethylene solidification of low-level wastes

    SciTech Connect

    Kalb, P.D.; Colombo, P.

    1985-02-01

    This topical report describes the results of an investigation on the solidification of low-level radioactive waste in polyethylene. Waste streams selected for this study included those which result from advanced volume reduction technologies (dry evaporator concentrate salts and incinerator ash) and those which remain problematic for solidification using contemporary agents (ion exchange resins). Four types of commercially available low-density polyethylenes were employed which encompass a range of processing and property characteristics. Process development studies were conducted to ascertain optimal process control parameters for successful solidification. Maximum waste loadings were determined for each waste and polyethylene type. Property evaluation testing was performed on laboratory-scale specimens to assess the potential behavior of actual waste forms in a disposal environment. Waste form property tests included water immersion, deformation under compressive load, thermal cycling and radionuclide leaching. Recommended waste loadings of 70 wt % sodium sulfate, 50 wt % boric acid, 40 wt % incinerator ash, and 30 wt % ion exchange resins, which are based on process control and waste form performance considerations are reported. 37 refs., 33 figs., 22 tabs.

  14. A lysimeter-based approach to quantify the impact of climate change on soil hydrological processes

    NASA Astrophysics Data System (ADS)

    Slawitsch, Veronika; Steffen, Birk; Herndl, Markus

    2016-04-01

    The predicted climate change involving increasing CO2 concentrations and increasing temperatures will have effects on both vegetation and soil properties and thus on the soil water balance. The aim of this work is to quantify the effects of changes in these climatic factors on soil hydrological processes and parameters. For this purpose data of six high precision weighable lysimeters will be used. The lysimeters are part of a Lysi-T-FACE concept, where free-air will be enriched with CO2 (FACE-Technique) and infrared heaters heat the plots for investigation on effects of increasing temperatures (T-FACE-Technique). The Lysi-T-FACE concept was developed on the „Clim Grass Site" at the HBLFA Raumberg-Gumpenstein (Styria, Austria) in 2011 and 2012 with a total of 54 experimental plots. These include six plots with lysimeters where the two climatic factors are varied in different combinations. On the basis of these grass land lysimeters the soil hydraulic parameters under different experimental conditions will be investigated. The lysimeters are equipped with TDR-Trime sensors and temperature sensors combined with tensiometers in different depths. In addition, a mechanical separation snow cover system is implemented to obtain a correct water balance in winter. To be able to infer differences between the lysimeters reliably a verification of functionalities and a plausibility check of the data from the lysimeters as well as adequate data corrections are needed. Both an automatic and a user-defined control including the recently developed filter method AWAT (Adaptive Window and Adaptive Threshold Filter) are combined with a visualisation tool using the software NI DIAdem. For each lysimeter the raw data is classified in groups of matric potentials, soil water contents and lysimeter weights. Values exceeding technical thresholds are eliminated and marked automatically. The manual data control is employed every day to obtain high precision seepage water weights. The

  15. Packaged low-level waste verification system

    SciTech Connect

    Tuite, K.T.; Winberg, M.; Flores, A.Y.; Killian, E.W.; McIsaac, C.V.

    1996-08-01

    Currently, states and low-level radioactive waste (LLW) disposal site operators have no method of independently verifying the radionuclide content of packaged LLW that arrive at disposal sites for disposal. At this time, disposal sites rely on LLW generator shipping manifests and accompanying records to insure that LLW received meets the waste acceptance criteria. An independent verification system would provide a method of checking generator LLW characterization methods and help ensure that LLW disposed of at disposal facilities meets requirements. The Mobile Low-Level Waste Verification System (MLLWVS) provides the equipment, software, and methods to enable the independent verification of LLW shipping records to insure that disposal site waste acceptance criteria are being met. The MLLWVS system was developed under a cost share subcontract between WMG, Inc., and Lockheed Martin Idaho Technologies through the Department of Energy`s National Low-Level Waste Management Program at the Idaho National Engineering Laboratory (INEL).

  16. Visualizing Moisture Storage in Basin Lysimeters Using Electrical Resistivity Tomography

    NASA Astrophysics Data System (ADS)

    Schnabel, W.; Munk, J.; Lee, W.

    2010-12-01

    Electrical resistivity tomography (ERT) was utilized to evaluate soil moisture in two large (10m x 20m x 2m) basin lysimeters over a four-year period in Anchorage, Alaska. The lysimeters were intended to test the efficacy of two competing landfill cover designs, thus water balance information was collected over the entire experimental period. The first lysimeter contained a thin (0.5m) layer of compacted soil within its 2m depth and was planted with local grasses. The second lysimeter contained no compacted soil layer and was planted with deep-rooting woody vegetation to maximize moisture removal via evapotranspiration. After four years of observation, 291mm of moisture percolated through the compacted soil lysimeter compared to 201mm in the evapotranspiration lysimeter. This presentation describes the observed water balance results, discusses efficacy of utilizing compacted soils versus evapotranspiration as the primary means of minimizing infiltration into engineered soil systems, and demonstrates the use of ERT as a technique for visualizing soil moisture storage.

  17. Geochemical Modeling of ILAW Lysimeter Water Extracts

    SciTech Connect

    Cantrell, Kirk J.

    2014-12-22

    Geochemical modeling results of water extracts from simulated immobilized low-activity waste (ILAW) glasses, placed in lysimeters for eight years suggest that the secondary phase reaction network developed using product consistency test (PCT) results at 90°C may need to be modified for field conditions. For sediment samples that had been collected from near the glass samples, the impact of glass corrosion could be readily observed based upon the pH of their water extracts. For unimpacted sediments the pH ranged from 7.88 to 8.11 with an average of 8.04. Sediments that had observable impacts from glass corrosion exhibited elevated pH values (as high as 9.97). For lysimeter sediment samples that appear to have been impacted by glass corrosion to the greatest extent, saturation indices determined for analcime, calcite, and chalcedony in the 1:1 water extracts were near equilibrium and were consistent with the secondary phase reaction network developed using PCT results at 90°C. Fe(OH)3(s) also appears to be essentially at equilibrium in extracts impacted by glass corrosion, but with a solubility product (log Ksp) that is approximately 2.13 units lower than that used in the secondary phase reaction network developed using PCT results at 90°C. The solubilities of TiO2(am) and ZrO2(am) also appear to be much lower than that assumed in the secondary phase reaction network developed using PCT results at 90°C. The extent that the solubility of TiO2(am) and ZrO2(am) were reduced relative to that assumed in the secondary phase reaction network developed using PCT results at 90°C could not be quantified because the concentrations of Ti and Zr in the extracts were below the estimated quantification limit. Gibbsite was consistently highly oversaturated in the extract while dawsonite was at or near equilibrium. This suggests that dawsonite might be a more suitable phase for the secondary phase reaction network than gibbsite under field conditions. This may be due to the

  18. FIELD STUDIES ON PARAHO RETORTED OIL SHALE LYSIMETERS: LEACHATE, VEGETATION, MOISTURE, SALINITY, AND RUNOFF, 1977-1980

    EPA Science Inventory

    A disposal scheme for Paraho retorted shale utilizing lysimeters to simulate a low-elevation (dry site) and a high-elevation (moist site) was constructed. Objectives of the study were to investigate (1) vegetative stabilization of Paraho retored shale, as affected by leaching and...

  19. Effects of dietary protein concentration on ammonia volatilization, nitrate leaching, and plant nitrogen uptake from dairy manure applied to lysimeters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This lysimeter experiment was designed to investigate the effects of dietary crude protein (CP) concentration on nitrate-N (NO3-N) and ammonia (NH3) losses from dairy manure applied to soil and manure N use for plant growth. Lactating dairy cows were fed diets with 16.7 (HighCP) or 14.8% (LowCP) cru...

  20. Low-level waste forum meeting reports

    SciTech Connect

    1990-12-31

    This paper provides highlights from the October 1990 meeting of the Low Level Radioactive Waste Forum. Topics of discussion included: a special session on liability and financial assurance needs; proposal to dispose of mixed waste at federal facilities; state plans for interim storage; and hazardous materials legislation.

  1. Vital parameters related low level laser radiation

    NASA Astrophysics Data System (ADS)

    Palmieri, Beniamino; Capone, Stefania

    2011-08-01

    The first work hypotesis is that biosensors on the patient detecting heart, breath rate and skin parameters, modulate laser radiation to enhance the therapeutic outcome; in the second work hypotesis: biofeedback could be effective, when integrated in the low level laser energy release.

  2. Low-level waste forum meeting reports

    SciTech Connect

    1991-12-31

    This report contains highlights from the 1991 fall meeting of the Low Level Radioactive Waste Forum. Topics included legal updates; US NRC updates; US EPA updates; mixed waste issues; financial assistance for waste disposal facilities; and a legislative and policy report.

  3. Low-level waste forum meeting reports

    SciTech Connect

    1993-12-31

    This paper provides the results of the winter meeting of the Low Level Radioactive Waste Forum. Discussions were held on the following topics: new developments in states and compacts; adjudicatory hearings; information exchange on siting processes, storage surcharge rebates; disposal after 1992; interregional access agreements; and future tracking and management issues.

  4. Low-level waste forum meeting reports

    SciTech Connect

    1995-12-31

    This paper provides highlights from the 1995 summer meeting of the Low Level radioactive Waste Forum. Topics included: new developments in state and compacts; federal waste management; DOE plans for Greater-Than-Class C waste management; mixed wastes; commercial mixed waste management; international export of rad wastes for disposal; scintillation cocktails; license termination; pending legislation; federal radiation protection standards.

  5. Infrared low-level wind shear work

    NASA Technical Reports Server (NTRS)

    Adamson, Pat

    1988-01-01

    Results of field experiments for the detection of clear air disturbance and low level wind shear utilizing an infrared airborne system are given in vugraph form. The hits, misses and nuisance alarms scores are given. Information is given on the infrared spatial resolution technique. The popular index of aircraft hazard (F= WX over g - VN over AS) is developed for a remote temperature sensor.

  6. Effects of soil type, irrigation volume and plant species on treatment of log yard run-off in lysimeters.

    PubMed

    Jonsson, Maria; Dimitriou, Ioannis; Aronsson, Pär; Elowson, Torbjörn

    2004-09-01

    Wet storage of timber and pulpwood produces large quantities of run-off water. A study was conducted to determine the purification efficiency of soil-plant systems for log yard run-off. Sixteen 1200-l lysimeters (1.2 m deep soil columns) with clay or sand soil were planted with willow (Salix sp.) or alder (Alnus glutinosa), and irrigated with run-off from a Norway spruce (Picea abies) log yard. Drainage water was analysed for total organic carbon (TOC), phenols, total P and total N in order to determine concentrations and levels of retention. High retention of TOC, phenols and P occurred in the lysimeters, but no clear differences between willows and alder or clay and sand were identified. Lysimeters with high levels of irrigation showed greater retention than those with low levels. Soil-plant systems using willow and alder could provide an alternative for log yard run-off purification: the key requirement is to optimise irrigation rather than manipulate the plants or soils. PMID:15325190

  7. Effect of rice husk gasification residue application on herbicide behavior in micro paddy lysimeter.

    PubMed

    Ok, Junghun; Pisith, Sok; Watanabe, Hirozumi; Thuyet, Dang Quoc; Boulange, Julien; Takagi, Kazuhiro

    2015-06-01

    Effects of rice husk gasification residues (RHGR) application on the fate of herbicides, butachlor and pyrazosulfuron-ethyl, in paddy water were investigated using micro paddy lysimeters (MPLs). The dissipation of both herbicides in paddy water was faster in the RHGR treated MPL than in the control MPL. The average concentrations of butachlor and pyrazosulfuron-ethyl in paddy water in the lysimeter treated with RHGR during 21 days were significantly reduced by 51% and 48%, respectively, as compared to those in the lysimeter without RHGR application. The half-lives (DT50) of butachlor in paddy water for control and treatment were 3.1 and 2.3 days respectively, and these values of pyrazosulfuron-ethyl were 3.0 and 2.2 days, respectively. Based on this study, RHGR application in rice paddy environment is an alternative method to reduce the concentration of herbicide in paddy field water and consequently to reduce potential pollution to aquatic environment. PMID:25763539

  8. Weighing Lysimeters for Developing Crop Coefficients and Efficient Irrigation Practices for Vegetable Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large weighing lysimeters are expensive but invaluable tools for measuring crop evapotranspiration and developing crop coefficients for horticultural crops. Crop coefficients are used by both growers and researchers to estimate crop water use and accurately schedule irrigations. Two lysimeters of ...

  9. Comparison of simple rain gauge measurements with precision lysimeter data

    NASA Astrophysics Data System (ADS)

    Hoffmann, Marieke; Schwartengräber, Reinhild; Wessolek, Gerd; Peters, Andre

    2016-06-01

    Standard precipitation measurement techniques are subject to random and systematic errors, affecting the exact determination of precipitation at ground level. The aim of this study was to find a useful and cost-efficient workaround to minimize these errors. For a period of 418 days, precipitation was measured by a tipping bucket rain gauge installed at 1 m height, three Hellmann rain gauges placed on the ground and three lysimeters. Precipitation catch of the lysimeters showed very small deviation (< 0.5%) and was regarded as reference. The tipping bucket at 1 m height caught 12.7% less precipitation. By contrast, ground-level Hellmann gauges caught, on average, similar precipitation as lysimeters. Both methods exhibited large undercatch in wintertime and low undercatch (tipping bucket) or even overcatch (Hellmann gauge) in summertime. Hellmann gauge measurements at ground level allow a fairly exact determination of precipitation for long time periods with low cost and effort.

  10. Lid design for low level waste container

    DOEpatents

    Holbrook, Richard H.; Keener, Wendell E.

    1995-01-01

    A container for low level waste includes a shell and a lid. The lid has a frame to which a planar member is welded. The lid frame includes a rectangular outer portion made of square metal tubing, a longitudinal beam extending between axial ends of the rectangular outer portion, and a transverse beam extending between opposite lateral sides of the rectangular outer portion. Two pairs of diagonal braces extend between the longitudinal beam and the four corners of the rectangular outer portion of the frame.

  11. Liquid low level waste management expert system

    SciTech Connect

    Ferrada, J.J.; Abraham, T.J. ); Jackson, J.R. )

    1991-01-01

    An expert system has been developed as part of a new initiative for the Oak Ridge National Laboratory (ORNL) systems analysis program. This expert system will aid in prioritizing radioactive waste streams for treatment and disposal by evaluating the severity and treatability of the problem, as well as the final waste form. The objectives of the expert system development included: (1) collecting information on process treatment technologies for liquid low-level waste (LLLW) that can be incorporated in the knowledge base of the expert system, and (2) producing a prototype that suggests processes and disposal technologies for the ORNL LLLW system. 4 refs., 9 figs.

  12. Lid design for low level waste container

    DOEpatents

    Holbrook, R.H.; Keener, W.E.

    1995-02-28

    A container for low level waste includes a shell and a lid. The lid has a frame to which a planar member is welded. The lid frame includes a rectangular outer portion made of square metal tubing, a longitudinal beam extending between axial ends of the rectangular outer portion, and a transverse beam extending between opposite lateral sides of the rectangular outer portion. Two pairs of diagonal braces extend between the longitudinal beam and the four corners of the rectangular outer portion of the frame. 6 figs.

  13. Low level vapor verification of monomethyl hydrazine

    NASA Technical Reports Server (NTRS)

    Mehta, Narinder

    1990-01-01

    The vapor scrubbing system and the coulometric test procedure for the low level vapor verification of monomethyl hydrazine (MMH) are evaluated. Experimental data on precision, efficiency of the scrubbing liquid, instrument response, detection and reliable quantitation limits, stability of the vapor scrubbed solution, and interference were obtained to assess the applicability of the method for the low ppb level detection of the analyte vapor in air. The results indicated that the analyte vapor scrubbing system and the coulometric test procedure can be utilized for the quantitative detection of low ppb level vapor of MMH in air.

  14. Low-level structural recognition of documents

    SciTech Connect

    Chenevoy, Y.; Belaied, A.

    1994-12-31

    This paper focuses on the qualitative approach of the low-level structured document analysis. The system identifies the different logical fields within the document and produces as output a structured flow with confidence scores. The strategy is driven by a generic model and by an OCR flow. Logical labels are attached to research areas after hypothesizing and testing typographical, lexical and contextual properties. A qualitative recognition is performed, which allows to amphasize ambiguities and unrecognized fields. Library references are treated to illustrate this method.

  15. Russian low-level waste disposal program

    SciTech Connect

    Lehman, L.

    1993-03-01

    The strategy for disposal of low-level radioactive waste in Russia differs from that employed in the US. In Russia, there are separate authorities and facilities for wastes generated by nuclear power plants, defense wastes, and hospital/small generator/research wastes. The reactor wastes and the defense wastes are generally processed onsite and disposed of either onsite, or nearby. Treating these waste streams utilizes such volume reduction techniques as compaction and incineration. The Russians also employ methods such as bitumenization, cementation, and vitrification for waste treatment before burial. Shallow land trench burial is the most commonly used technique. Hospital and research waste is centrally regulated by the Moscow Council of Deputies. Plans are made in cooperation with the Ministry of Atomic Energy. Currently the former Soviet Union has a network of low-level disposal sites located near large cities. Fifteen disposal sites are located in the Federal Republic of Russia, six are in the Ukraine, and one is located in each of the remaining 13 republics. Like the US, each republic is in charge of management of the facilities within their borders. The sites are all similarly designed, being modeled after the RADON site near Moscow.

  16. Weighing lysimeters for the determination of crop water requirements and crop coefficients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weighing lysimeters are accurate instruments to measure crop evapotranspiration. Three weighing lysimeters consisting of undisturbed 1.5- × 2.0-m surface area by 2.5-m depth cores of soil, were constructed and installed at the Texas Agricultural Experiment Station in Uvalde, Texas. Two lysimeters, e...

  17. A method for installing zero-tension pan and wick lysimeters in soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zero-tension pan lysimeters and passive capillary fiberglass wick lysimeters are useful in determining water quality and volumetric aspects of subsurface water flow. Installation of pan and wick lysimeters beneath undisturbed soil may be complicated by the tendency for the soil to cave-in as the lys...

  18. Long-term fate of the herbicide cinosulfuron in lysimeters planted with rice over four consecutive years.

    PubMed

    Lee, Jae Koo; Führ, Fritz; Kwon, Jeong Wook; Ahn, Ki Chang

    2002-10-01

    In order to elucidate the long-term fate of the sulfonylurea herbicide cinosulfuron, the 14C-labelled chemical was applied to a clay loam soil, encased in two lysimeters, 22 days after rice (Oryza sativa L.) transplanting, and rice plants were grown for four consecutive years. Throughout the experimental period, leaching through soil profiles, absorption and translocation by rice plants, and distribution of 14C by downward movement in the soil layers were clarified. The total volume of leachates collected through the lysimeter soil over the four years amounted to 168 and 146 L in lysimeters I and II, respectively. The leachates contained 2.43% and 2.99% of the originally applied 14C-radioactivity, corresponding to an average concentration of 0.29 and 0.41 microg/L as the cinosulfuron equivalent in lysimeters I and II, respectively. The total 14C-radioactivity translocated to rice plants in the third and fourth year was 0.69% and 0.60% (lysimeter I), and 1.02% and 0.84% (lysimeter II) of the 14C applied, respectively. Larger amounts of cinosulfuron equivalents (0.54-0.75%) remained in the straw in the fourth year than in any other parts. The 14C-radioactivities distributed down to a depth of 70 cm after four years were 56.71-57.52% of the 14C applied, indicating the continuous downward movement and degradation of cinosulfuron in soil. The non-extractable residues were more than 88% of the soil radioactivity and some 45-48% of them was incorporated into the humin fraction. The 14C-radioactivity partitioned into the aqueous phase was nearly 30% of the extractable 14C, suggesting strongly that cinosulfuron was degraded into some polar products during the experimental period. It was found out in a supplemental investigation that flooding and constant higher temperature enhanced mineralization of [14C]cinosulfuron to 14CO2 in soil, indicating the possibility of chemical hydrolysis and microbial degradation of the compound in the flooded lysimeter soil. PMID:12375864

  19. Concepts and data-collection techniques used in a study of the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Healy, R.W.; DeVries, M.P.; Striegl, R.G.

    1986-01-01

    A study of water and radionuclide movement through the unsaturated zone is being conducted at the low level radioactive waste disposal site near Sheffield, Illinois. Included in the study are detailed investigations of evapotranspiration, movement of water through waste trench covers, and movement of water and radionuclides (dissolved and gaseous) from the trenches. An energy balance/Bowen ratio approach is used to determine evapotranspiration. Precipitation, net radiation, soil-heat flux, air temperature and water vapor content gradients, wind speed, and wind direction are measured. Soil water tension is measured with tensiometers which are connected to pressure transducers. Meteorological sensors and tensiometers which are connected to pressure transducers. Meteorological sensors and tensiometers are monitored with automatic data loggers. Soil moisture contents are measured through small-diameter access tubes with neutron and gamma-ray attenuation gages. Data beneath the trenches are obtained through a 130-meter-long tunnel which extends under four of the trenches. Water samples are obtained with suction lysimeters, and samples of the geologic material are obtained with core tubes. These samples are analyzed for radiometric and inorganic chemistry. Gas samples are obtained from gas piezometers and analyzed for partial pressures of major constituents, Radon-222, tritiated water vapor, and carbon-14 dioxide. (USGS)

  20. A comprehensive filtering scheme for high-resolution estimation of the water balance components from high-precision lysimeters

    NASA Astrophysics Data System (ADS)

    Hannes, M.; Wollschlager, U.; Schrader, F.; Durner, W.; Gebler, S.; Putz, T.; Fank, J.; von Unold, G.; Vogel, H.-J.

    2015-08-01

    Large weighing lysimeters are currently the most precise method to directly measure all components of the terrestrial water balance in parallel via the built-in weighing system. As lysimeters are exposed to several external forces such as management practices or wind influencing the weighing data, the calculated fluxes of precipitation and evapotranspiration can be altered considerably without having applied appropriate corrections to the raw data. Therefore, adequate filtering schemes for obtaining most accurate estimates of the water balance components are required. In this study, we use data from the TERENO (TERrestrial ENvironmental Observatories) SoilCan research site in Bad Lauchstadt to develop a comprehensive filtering procedure for high-precision lysimeter data, which is designed to deal with various kinds of possible errors starting from the elimination of large disturbances in the raw data resulting e.g., from management practices all the way to the reduction of noise caused e.g., by moderate wind. Furthermore, we analyze the influence of averaging times and thresholds required by some of the filtering steps on the calculated water balance and investigate the ability of two adaptive filtering methods (the adaptive window and adaptive threshold filter (AWAT filter; Peters et al., 2014), and a new synchro filter applicable to the data from a set of several lysimeters) to further reduce the filtering error. Finally, we take advantage of the data sets of all 18 lysimeters running in parallel at the Bad Lauchstadt site to evaluate the performance and accuracy of the proposed filtering scheme. For the tested time interval of 2 months, we show that the estimation of the water balance with high temporal resolution and good accuracy is possible. The filtering code can be downloaded from the journal website as Supplement to this publication.

  1. Measurements for low level RF control systems

    NASA Astrophysics Data System (ADS)

    Simrock, S. N.

    2007-08-01

    The low level RF control system for the European x-ray free electron laser, which is based on TESLA technology, requires information on a large number of signals and parameters which are either directly measurable as physical signals or must be derived from the physical signals. In most cases, calibrations are required to obtain the desired quantities. The measured signals are used in the real time feedback loops for field and resonance control, and for diagnostic purposes to support automation and exception handling. Good system models and powerful signal processors (including field programmable gate arrays and digital signal processors) combined with fast communication links allow for processing a large number of complex algorithms in real time. Several of these algorithms have been implemented at the free electron laser at Hamburg (FLASH) for evaluation and have increased the availability of the facility for user operation.

  2. Low level image segmentation: an expert system.

    PubMed

    Nazif, A M; Levine, M D

    1984-05-01

    A major problem in robotic vision is the segmentation of images of natural scenes in order to understand their content. This paper presents a new solution to the image segmentation problem that is based on the design of a rule-based expert system. General knowledge about low level properties of processes employ the rules to segment the image into uniform regions and connected lines. In addition to the knowledge rules, a set of control rules are also employed. These include metarules that embody inferences about the order in which the knowledge rules are matched. They also incorporate focus of attention rules that determine the path of processing within the image. Furthermore, an additional set of higher level rules dynamically alters the processing strategy. This paper discusses the structure and content of the knowledge and control rules for image segmentation. PMID:21869225

  3. Airborne infrared low level wind shear predictor

    NASA Technical Reports Server (NTRS)

    Kuhn, P. M.; Kurkowski, R. L.

    1984-01-01

    The operating principles and test performance of an airborne IR (13-16 micron) temperature-sensing detection and warning system for low-level wind shear (LLWS) are presented. The physics of LLWS phenomena and of the IR radiometer are introduced. The cold density-current outflow or gust front related to LLWS is observed in the IR spectrum of CO2 by a radiometer with + or - 0.5-C accuracy at 0.5-Hz sampling rate; LLWS alerts are given on the basis of specific criteria. Test results from the JAWS experiments conducted at Denver in July 1982, are presented graphically and discussed. The feasibility of the passive IR system is demonstrated, with an average warning time of 51 sec, corresponding to a distance from touchdown of about 2 miles.

  4. Detecting low levels of radionuclides in fluids

    DOEpatents

    Patch, Keith D.; Morgan, Dean T.

    2000-01-01

    An apparatus and method for detecting low levels of one or more radionuclides in a fluid sample uses a substrate that includes an ion exchange resin or other sorbent material to collect the radionuclides. A collecting apparatus includes a collecting chamber that exposes the substrate to a measured amount of the fluid sample such that radionuclides in the fluid sample are collected by the ion exchange resin. A drying apparatus, which can include a drying chamber, then dries the substrate. A measuring apparatus measures emissions from radionuclides collected on the substrate. The substrate is positioned in a measuring chamber proximate to a detector, which provides a signal in response to emissions from the radionuclides. Other analysis methods can be used to detect non-radioactive analytes, which can be collected with other types of sorbent materials.

  5. R&D ERL: Low level RF

    SciTech Connect

    Smith, K.

    2010-01-15

    A superconducting RF (SRF) Energy Recovery Linac (ERL) is currently under development at the Collider-Accelerator Department (C-AD) at Brookhaven National Laboratory (BNL). The major components from an RF perspective are (a) a 5-cell SRF ERL cavity, (b) an SRF photocathode electron gun, and (c) a drive laser for the photocathode gun. Each of these RF subsystems has its own set of RF performance requirements, as well as common requirements for ensuring correct synchronism between them. A low level RF (LLRF) control system is currently under development, which seeks to leverage both technology and experience gained from the recently commissioned RHIC LLRF system upgrade. This note will review the LLRF system requirements and describe the system to be installed at the ERL.

  6. Statistical analysis of low level atmospheric turbulence

    NASA Technical Reports Server (NTRS)

    Tieleman, H. W.; Chen, W. W. L.

    1974-01-01

    The statistical properties of low-level wind-turbulence data were obtained with the model 1080 total vector anemometer and the model 1296 dual split-film anemometer, both manufactured by Thermo Systems Incorporated. The data obtained from the above fast-response probes were compared with the results obtained from a pair of Gill propeller anemometers. The digitized time series representing the three velocity components and the temperature were each divided into a number of blocks, the length of which depended on the lowest frequency of interest and also on the storage capacity of the available computer. A moving-average and differencing high-pass filter was used to remove the trend and the low frequency components in the time series. The calculated results for each of the anemometers used are represented in graphical or tabulated form.

  7. Mechanisms of low level light therapy

    NASA Astrophysics Data System (ADS)

    Hamblin, Michael R.; Demidova, Tatiana N.

    2006-02-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing tissue damage has been known for almost forty years since the invention of lasers. Originally thought to be a peculiar property of laser light (soft or cold lasers), the subject has now broadened to include photobiomodulation and photobiostimulation using non-coherent light. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial. This likely is due to two main reasons; firstly the biochemical mechanisms underlying the positive effects are incompletely understood, and secondly the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. In particular a biphasic dose response has been frequently observed where low levels of light have a much better effect than higher levels. This introductory review will cover some of the proposed cellular chromophores responsible for the effect of visible light on mammalian cells, including cytochrome c oxidase (with absorption peaks in the near infrared) and photoactive porphyrins. Mitochondria are thought to be a likely site for the initial effects of light, leading to increased ATP production, modulation of reactive oxygen species and induction of transcription factors. These effects in turn lead to increased cell proliferation and migration (particularly by fibroblasts), modulation in levels of cytokines, growth factors and inflammatory mediators, and increased tissue oxygenation. The results of these biochemical and cellular changes in animals and patients include such benefits as increased healing in chronic wounds, improvements in sports injuries and

  8. Large Plate Lysimeter Efficiency for Collecting Water Transported from Soil to Ground Water

    SciTech Connect

    Robison, W; Stone, E L; Hamilton, T

    2004-04-14

    A large, zero-tension, plate lysimeter (3.05 x 2.13 m) was installed to intercept percolating soil water at Bikini Atoll (11 35'N, 165 25'E), a former nuclear test-site. In two experiments controlled amounts of irrigation water were applied over the lysimeter and leachate water was collected. Evapotranspiration (ET) calculations were made using the Penman-Monteith equation and climate data collected at the atoll. The efficiency of the lysimeter was essentially 100% in contrast to low efficiencies reported for smaller plate lysimeters. Lysimeter design, installation, and water balance results are discussed.

  9. Weighing lysimeter studies as basis for irrigation management

    NASA Astrophysics Data System (ADS)

    Cepuder, P.; Nolz, R.

    2009-04-01

    Efficient irrigation management aims for an optimum water supply for the plant in order to maximize yield on the one hand, and minimize losses of water and energy on the other hand. One approach in this regard is to keep the soil water content within an ideal range for plant water uptake. Therefore, it is essential to know the current soil water content during the vegetation period. In general, the soil water content is increased by rainfall R and irrigation I, and it is decreased by evapotranspiration ET and deep percolation P. Provided that the necessary data are available, the change of the soil water content dS can be computed using the water balance equation dS=R+I-ET-P. Beside this method, the soil water content can be measured using soil water sensors. For example, FDR-sensors can measure the water content in a soil profile with a high temporal resolution. Both methods are the basis for irrigation scheduling in the Marchfeld, an intensively used agricultural area in the eastern part of Austria. The lysimeter- and agro-meteorological station in Groß-Enzersdorf lies in the Marchfeld. The lysimeters are operated by the University of Natural Resources and Applied Life Sciences, Vienna. Two weighing lysimeters are used to adapt and improve irrigation management practices. One lysimeter is grown with grass in order to determine the reference-evapotranspiration, the second one is planted with different annual crops that are typical for the Marchfeld. The amount of percolation water and the change of weight are measured and stored automatically. FDR-sensors are installed in the lysimeter for measuring the soil water content in different soil layers. ET is determined from the lysimeter data and calculated from equations, e.g. Penman-Montieth. The essential weather data originate from the nearby meteorological station of the Austrian national weather service. As a result, daily measured soil water content is compared with calculated soil water and FDR-sensor readings

  10. Disposal of low-level and low-level mixed waste: audit report

    SciTech Connect

    1998-09-03

    The Department of Energy (Department) is faced with the legacy of thousands of contaminated areas and buildings and large volumes of `backlog` waste requiring disposal. Waste management and environmental restoration activities have become central to the Department`s mission. One of the Department`s priorities is to clean up former nuclear weapons sites and find more effective and timely methods for disposing of nuclear waste. This audit focused on determining if the Department was disposing of low-level and low-level mixed waste in the most cost-effective manner.

  11. A Protocol for Collecting and Constructing Soil Core Lysimeters.

    PubMed

    Saporito, Louis S; Bryant, Ray B; Kleinman, Peter J A

    2016-01-01

    Leaching of nutrients from land applied fertilizers and manure used in agriculture can lead to accelerated eutrophication of surface water. Because the landscape has complex and varied soil morphology, an accompanying disparity in flow paths for leachate through the soil macropore and matrix structure is present. The rate of flow through these paths is further affected by antecedent soil moisture. Lysimeters are used to quantify flow rate, volume of water and concentration of nutrients leaching downward through soils. While many lysimeter designs exist, accurately determining the volume of water and mass balance of nutrients is best accomplished with bounded lysimeters that leave the natural soil structure intact. Here we present a detailed method for the extraction and construction of soil core lysimeters equipped with soil moisture sensors at 5 cm and 25 cm depths. Lysimeters from four different Coastal Plain soils (Bojac, Evesboro, Quindocqua and Sassafras) were collected on the Delmarva Peninsula and moved to an indoor climate controlled facility. Soils were irrigated once weekly with the equivalent of 2 cm of rainfall to draw down soil nitrate-N concentrations. At the end of the draw down period, poultry litter was applied (162 kg TN ha(-1)) and leaching was resumed for an additional five weeks. Total recovery of applied irrigation water varied from 71% to 85%. Nitrate-N concentration varied over the course of the study from an average of 27.1 mg L(-1) before litter application to 40.3 mg L(-1) following litter application. While greatest flux of nutrients was measured in soils dominated by coarse sand (Sassafras) the greatest immediate flux occurred from the finest textured soil with pronounced macropore development (Quindocqua). PMID:27341654

  12. Experimental incineration of low level radioactive samples.

    PubMed

    Yumoto, Y; Hanafusa, T; Nagamatsu, T; Okada, S

    2000-08-01

    To determine the volume reduction potential for incineration of radioactivity in low-level radioactive waste, an incineration experiment was performed at the Okayama University Radioisotope Center (OURIC). Solid low-level radioactive samples (LLRS) were prepared for 15 routinely used radionuclides (45Ca, 1251, 32p, 33p, 35S, 59Fe, 123I, 131I, 67Ga, 99mTc, 111In, 3H, 14C, 51Cr, and 201Tl). For each radionuclide, incinerated one at a time, the smoke duct radioisotope concentration was less than 1/10 of the regulatory concentration limit (The Japanese law concerning prevention of radiation hazard due to radioisotopes, etc.). The radionuclide-containing combustible and semi-combustible LLRS were incinerated at the AP-1 50R furnace erected at OURIC, and the distribution of radioactivity inside and outside the furnace was measured. In the experimental incineration of LLRS containing these 15 radionuclides, the fractions released (RF) in the gas phase of the final smoke duct ranged from 0.165 to 0.99. The radioactivities remaining in the incineration residue were 99mTc, 87%; 59Fe, 83.1%; 45Ca, 75%; 51Cr, 62.1%; 33P, 62.0%; 32P, 61.1%; 67Ga, 57.7%; 35S, 26.0%; 111In, 21.1%; 201Tl, 16.6%; 123I, 11.9%; 131I, 8.2%; 125I, 2.4%; 14C, 0.39%; 3H, 0.04%. In the incineration of LLR S containing 35S, the rate of adhesion to the furnace wall was lower at high-temperature (809 degrees C) incineration than at low-temperature (376 degrees C) incineration. For LLRS containing one of the three radioiodines, 123I, 125I, or 131I, no such difference was observed between low (372 degrees C) and high (827 degrees C) temperature incineration (RF varied from 0.82 to 0.94). PMID:10910400

  13. The effects of radiative transfer on low-level cyclogenesis

    SciTech Connect

    Leach, M.J.; Raman, S.

    1995-04-01

    Many investigators have documented the role that thermodynamic forcing due to radiative flux divergence plays in the enhancement or generation of circulation. Most of these studies involve large-scale systems, small-scale systems such as thunderstorms, and squall lines. The generation of circulation on large scales results from the creation of divergence in the upper troposphere and the maintenance of low-level potentially unstable air, and the maintenance of baroclinicity throughout the atmosphere. On smaller scales, radiative flux divergence acts similarly. In the thunderstorms and squall lines, the radiative forcing acts as a pump, increasing the divergence at the top of the storm systems and increasing the updraft velocity and the intensity of inflow at mid-levels in the storm systems. Other researchers have examined the role of surface processes and low-level baroclinicity in east coast cyclogenesis. In this paper, we examine the interactive role that radiative flux divergence, clouds, and surface processes play in low-level cyclogenesis and the creation or maintenance of the boundary layer baroclinicity.

  14. Forearm muscle oxygenation decreases with low levels of voluntary contraction

    NASA Technical Reports Server (NTRS)

    Murthy, G.; Kahan, N. J.; Hargens, A. R.; Rempel, D. M.

    1997-01-01

    The purpose of our investigation was to determine if the near infrared spectroscopy technique was sensitive to changes in tissue oxygenation at low levels of isometric contraction in the extensor carpi radialis brevis muscle. Nine subjects were seated with the right arm abducted to 45 degrees, elbow flexed to 85 degrees, forearm pronated 45 degrees, and wrist and forearm supported on an armrest throughout the protocol. Altered tissue oxygenation was measured noninvasively with near infrared spectroscopy. The near infrared spectroscopy probe was placed over the extensor carpi radialis brevis of the subject's right forearm and secured with an elastic wrap. After 1 minute of baseline measurements taken with the muscle relaxed, four different loads were applied just proximal to the metacarpophalangeal joint such that the subjects isometrically contracted the extensor carpi radialis brevis at 5, 10, 15, and 50% of the maximum voluntary contraction for 1 minute each. A 3-minute recovery period followed each level of contraction. At the end of the protocol, with the probe still in place, a value for ischemic tissue oxygenation was obtained for each subject. This value was considered the physiological zero and hence 0% tissue oxygenation. Mean tissue oxygenation (+/-SE) decreased from resting baseline (100% tissue oxygenation) to 89 +/- 4, 81 +/- 8, 78 +/- 8, and 47 +/- 8% at 5, 10, 15, and 50% of the maximum voluntary contraction, respectively. Tissue oxygenation levels at 10, 15, and 50% of the maximum voluntary contraction were significantly lower (p < 0.05) than the baseline value. Our results indicate that tissue oxygenation significantly decreases during brief, low levels of static muscle contraction and that near infrared spectroscopy is a sensitive technique for detecting deoxygenation noninvasively at low levels of forearm muscle contraction. Our findings have important implications in occupational medicine because oxygen depletion induced by low levels of muscle

  15. MESERAN Calibration for Low Level Organic Residues

    SciTech Connect

    Benkovich, M.G.

    2004-04-08

    Precision cleaning studies done at Honeywell Federal Manufacturing & Technologies (FM&T), the Kansas City Plant (KCP), and at other locations within the Department of Energy (DOE) Weapons complex over the last 30 years have depended upon results from MESERAN Evaporative Rate Analysis for detecting low levels of organic contamination. The characterization of the surface being analyzed is carried out by depositing a Carbon-14 tagged radiochemical onto the test surface and monitoring the rate at which the radiochemical disappears from the surface with a Geiger-Mueller counter. In the past, the total number of counts over a 2-minute span have been used to judge whether a surface is contaminated or not and semi-quantitatively to what extent. This technique is very sensitive but has not enjoyed the broad acceptance of a purely quantitative analysis. The work on this project developed calibrations of various organic contaminants typically encountered in KCP operations. In addition, a new analysis method was developed to enhance the ability of MESERAN Analyzers to detect organic contamination and yield quantitative data in the microgram and nanogram levels.

  16. Language abstractions for low level optimization techniques

    NASA Astrophysics Data System (ADS)

    Dévai, Gergely; Gera, Zoltán; Kelemen, Zoltán

    2012-09-01

    In case of performance critical applications programmers are often forced to write code at a low abstraction level. This leads to programs that are hard to develop and maintain because the program text is mixed up by low level optimization tricks and is far from the algorithm it implements. Even if compilers are smart nowadays and provide the user with many automatically applied optimizations, practice shows that in some cases it is hopeless to optimize the program automatically without the programmer's knowledge. A complementary approach is to allow the programmer to fine tune the program but provide him with language features that make the optimization easier. These are language abstractions that make optimization techniques explicit without adding too much syntactic noise to the program text. This paper presents such language abstractions for two well-known optimizations: bitvectors and SIMD (Single Instruction Multiple Data). The language features are implemented in the embedded domain specific language Feldspar which is specifically tailored for digital signal processing applications. While we present these language elements as part of Feldspar, the ideas behind them are general enough to be applied in other language definition projects as well.

  17. Investigating effects of different evapotranspiration (ET) schemes on soil water dynamics and ET partitioning: a large lysimeter case of summer maize in a semi-arid environment northwest of China

    NASA Astrophysics Data System (ADS)

    Yu, L.; Zeng, Y.; Su, Z.; Cai, H.; Zheng, Z.

    2015-09-01

    Different evapotranspiration (ET) schemes can affect significantly the performance of land surface models in capturing the soil water dynamics and ET partitioning over various land cover and climates, the accurate understanding of which is crucial to determine the effective irrigation. In this study, a land model considering the coupled transfer of water, vapor and heat in the soil, with two alternative ET schemes, was used to investigate how the coupled mechanism can affect the soil water dynamics in a crop field and how the ET partitioning was influenced. There are two different evapotranspiration (ET) schemes, one is based on reference crop evapotranspiration (ET0) and use LAI to partition into soil evaporation and transpiration, denoted as the ETind scheme; the other is one-step calculation of actual soil evaporation and potential transpiration by incorporating canopy minimum resistance and actual soil resistance into Penman-Monteith model, denoted as the ETdir scheme. Results indicated that the coupled model with the two different ET schemes differed in simulating soil water content and crop evapotranspiration components while agreed well for the simulation of soil temperature. Considering the aerodynamic and surface resistance terms made the ETdir scheme better in simulating soil evaporation especially after irrigations. Furthermore, the results of different crop growth scenarios indicated that the uncertainty in LAI played an important role in estimating the relative transpiration and evaporation fraction. The soil drying seemed to intensify the disturbance of maximum rooting depth and root growth rate in calculating ET components. The former was more important at the late growing season while the latter dominated at the early growing season.

  18. Investigation of Low-Level Cascadia Tremor Between Major Episodes

    NASA Astrophysics Data System (ADS)

    Ulberg, C.; Wech, A. G.; Creager, K. C.

    2006-12-01

    Major episodes of episodic tremor and slip (ETS) located under the Olympic peninsula, Washington, and further north occur every 14 months and have been well-studied using both seismic and geodetic data. The next major episode is expected in November 2006. We look at the interval between major events using seismic data and find that there are still tremor episodes, although of smaller duration and magnitude. We examined vertical component data from 22 Pacific Northwest Seismograph Network seismometers broadly distributed across western Washington and Oregon. The data were band-pass filtered at 1 to 6 Hz. An envelope function calculated from these waveforms was then low-pass filtered at 0.03 Hz. We classify tremor as an emergent increase in seismic activity across multiple stations lasting anywhere from 10 minutes to many hours and exhibiting similarly shaped waveforms for nearby stations. Crude estimates of tremor location are based on the geographic variability of tremor amplitude. Typical smaller tremor bursts occur over 2 to 3 days, containing periods of up to 8 continuous hours exhibiting similar waveforms, and appear in 2 to 8 stations at a time. The longest period without any tremor was 10 days. Preliminary analysis shows that more tremor occurs under Washington than Oregon and occurs with a possible two-week periodicity, suggesting a potential effect of tidal forcing.

  19. Monitoring the performance of an alternative cover using caisson lysimeters

    SciTech Connect

    Waugh, W.J.; Smith, G.M.; Mushovic, P.S.

    2004-02-29

    The U.S. Department of Energy (DOE) office in Grand Junction, Colorado, and the U.S. Environmental Protection Agency (EPA), Region 8, collaborated on a series of field lysimeter studies to design and monitor the performance of an alternative cover for a uranium mill tailings disposal cell at the Monticello, Utah, Superfund Site. Because groundwater recharge is naturally limited at Monticello in areas with thick loess soils, DOE and EPA chose to design a cover for Monticello using local soils and a native plant community to mimic this natural soilwater balance. Two large drainage lysimeters fabricated of corrugated steel culvert lined with high-density polyethylene were installed to evaluate the hydrological and ecological performance of an alternative cover design constructed in 2000 on the disposal cell. Unlike conventional, lowpermeability designs, this cover relies on (1) the water storage capacity of a 163-cm soil “sponge” layer overlying a sand-and-gravel capillary barrier to retain precipitation while plants are dormant and (2) native vegetation to remove precipitation during the growing season. The sponge layer consists of a clay loam subsoil compacted to 1.65 g/cm2 in one lysimeter and a loam topsoil compacted to 1.45 g/cm2 in the other lysimeter, representing the range of as-built conditions constructed in the nearby disposal cell cover. About 0.1 mm of drainage occurred in both lysimeters during an average precipitation year and before they were planted, an amount well below the EPA target of <3.0 mm/yr. However, the cover with less compacted loam topsoil sponge had a 40% greater water storage capacity than the cover with overly compacted clay loam subsoil sponge. The difference is attributable in part to higher green leaf area and water extraction by plants in the loam topsoil. The lesson learned is that seemingly subtle differences in soil types, sources, and compaction can result in salient differences in performance. Diverse, seeded communities of

  20. Numerical study of different bottom boundary conditions on water flow in lysimeters

    NASA Astrophysics Data System (ADS)

    Groh, Jannis; Vanderborght, Jan; Pütz, Thomas; Vereecken, Harry

    2015-04-01

    The separation of the bottom of the lysimeter from its surroundings in the field introduces an artificial boundary that may impact the water balance of lysimeters. The use of tension controlled lysimeter (TCL) prevents an artificial boundary at the end of the lysimeter. Water flow across the lysimeter bottom can be controlled by the adjustment of matric potentials at the lower end of the lysimeter to measured field conditions in the close vicinity of the facility. However lysimeters are often transferred from the place where the soil monoliths were sampled to another location for practical reasons or to study the effect of climate change (e.g. SOILCan). The water flux across the bottom boundary of translocated TCL can be affected if climatic conditions, soil properties and the hydrogeological setting in the field differ from the place where the lysimeter was taken from. To assess the potential impact of different bottom boundary conditions on the water balance of translocated TCL a numerical study in virtual soils was conducted. We present a comparison of different approaches using water balance simulations. Results shows that water balance components of translocated TCL are sensitive towards the soil hydraulic parameters and hydrogeological setting in the field. The change in field conditions can impact the water flux dynamic across the lysimeter bottom, change the evaporation and the plant water uptake and release. A shift in the climate regime (translocation) will modify the depth and dynamics of the water table and impact the water balance of lysimeters.

  1. Issue briefs on low-level radioactive wastes

    SciTech Connect

    Not Available

    1981-01-01

    This report contains 4 Issue Briefs on low-level radioactive wastes. They are entitled: Handling, Packaging, and Transportation, Economics of LLW Management, Public Participation and Siting, and Low Level Waste Management.

  2. Construction and evaluation of simulated pilot scale landfill lysimeter in Bangladesh.

    PubMed

    Rafizul, Islam M; Howlader, Milon Kanti; Alamgir, Muhammed

    2012-11-01

    This research concentrates the design, construction and evaluation of simulated pilot scale landfill lysimeter at KUET campus, Khulna, Bangladesh. Both the aerobic and anaerobic conditions having a base liner and two different types of cap liner were simulated. After the design of a reference cell, the construction of landfill lysimeter was started in January 2008 and completed in July 2008. In all construction process locally available civil construction materials were used. The municipal solid waste (MSW) of 2800-2985 kg having the total volume of 2.80 m(3) (height 1.6 m) and moisture content of 65% was deposited in each lysimeter by applying required compaction energy. In contrast, both the composition in terms of methane (CH(4)), carbon dioxide (CO(2)) and oxygen (O(2)) as well as the flow rate of landfill gas (LFG) generated from MSW in landfill lysimeter were measured and varied significantly in relation to the variation of lysimeter operational condition. Moreover, anaerobic lysimeter-C shows the highest composition of LFG in compare to the anaerobic lysimeter-B due to the providing of lower compaction of cap liner in anaerobic lysimeter-C. Here, it is interesting to note that in absence of compacted clay liner (CCL) and hence percolation of rainwater that facilitates rapid degradation of MSW in aerobic lysimeter-A has resulted in the highest settlement than that of anaerobic landfill lysimeter-B and C. Moreover, in case of anaerobic lysimeter-B and C, the leachate generation was lower than that of aerobic lysimeter-A due to the providing of cap liner in anaerobic lysimeter-B and C, played an important role to reduce the percolation of rainwater. The study also reveals that the leachate pollution index (LPI) has decreased in relation to the increasing of elapsed period as well as the LPI for collection system of aerobic lysimeter-A was higher than that of the collection system of anaerobic lysimeter-B and C. Finally, it can be depicted that LPI for lysimeter

  3. Design of top covers supporting aerobic in situ stabilization of old landfills - An experimental simulation in lysimeters

    SciTech Connect

    Hrad, Marlies; Huber-Humer, Marion; Wimmer, Bernhard; Reichenauer, Thomas G.

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Tested engineered covers as surrogate to gas extraction during and after in situ aeration. Black-Right-Pointing-Pointer Examined how covers influence gas emissions, water balance and leachate generation. Black-Right-Pointing-Pointer Investigated effect of top covers on air-distribution in waste mass during aeration. Black-Right-Pointing-Pointer We suggest criteria and cover design to meet the demands during and after aeration. Black-Right-Pointing-Pointer Such cover systems may offer greenhouse gas emission reduction also after active aeration. - Abstract: Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 Multiplication-Sign 2 Multiplication-Sign 3 m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH{sub 4} loadings up to 300 l CH{sub 4}/m{sup 2} d. In addition, the compost material provided high air permeability

  4. Simulating the dissipation of two herbicides using micro paddy lysimeters.

    PubMed

    Nhung, Dang Thi Tuyet; Phong, Thai Khanh; Watanabe, Hirozumi; Iwafune, Takashi; Thuyet, Dang Quoc

    2009-11-01

    A set of packed micro paddy lysimeters, placed in a greenhouse, was used to simulate the dissipation of two herbicides, simetryn and thiobencarb, in a controlled environment. Data from a field monitoring study in 2003, including the soil condition and water balances, were used in the simulation. The herbicides were applied and monitored over a period of 21 d. The water balances under two water management scenarios, intermittent irrigation management (AI) and continuous irrigation management (CI), were simulated. In the AI scenario, the pattern of herbicide dissipation in the surface water of the field were simulated, following the first-order kinetics. In the CI scenario, similarity was observed in most lysimeter and field concentrations, but there were differences in some data points. Dissipation curves of both herbicides in the surface water of the two simulated scenarios were not significantly different (P>0.05) from the field data except for intercept of the thiobencarb curve in the CI scenario. The distribution of simetryn and thiobencarb in the soil profile after simulation were also similar to the field data. The highest concentrations of both herbicides were found on the topsoil layer at 0-2.5 cm depth. Only a small amount of herbicides moved down to the deeper soil layers. Micro paddy lysimeters are thus a good alternative for the dissipation study of pesticides in the paddy environment. PMID:19811801

  5. Design of top covers supporting aerobic in situ stabilization of old landfills--an experimental simulation in lysimeters.

    PubMed

    Hrad, Marlies; Huber-Humer, Marion; Wimmer, Bernhard; Reichenauer, Thomas G

    2012-12-01

    Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 × 2 × 3m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH(4) loadings up to 300 lCH(4)/m(2)d. In addition, the compost material provided high air permeability even at 100% water holding capacity (WHC). In contrast, the more cohesive, mineral soil cover was expected to cause a notably uniform distribution of the injected air within the waste layer. Laboratory results also revealed sufficient air permeability of the soil materials (TS-F and SS-Z) placed in lysimeter C. However, at higher compaction density SS-Z became impermeable at 100% WHC. Methane emissions from the reference lysimeter with the smaller substrate cover (12-52 g CH(4)/m(2)d) were significantly higher than fluxes from the other lysimeters (0-19 g CH(4)/m(2)d) during in situ aeration. Regarding water balance, lysimeters covered with

  6. Revisiting hydraulic hysteresis based on long-term monitoring of hydraulic states in lysimeters

    NASA Astrophysics Data System (ADS)

    Hannes, M.; Wollschläger, U.; Wöhling, T.; Vogel, H.-J.

    2016-05-01

    Hysteretic processes have been recognized for decades as an important characteristic of soil hydraulic behavior. Several studies confirmed that wetting and drying periods cannot be described by a simple functional relationship, and that some nonequilibrium of the water retention characteristics has to be taken into account. A large number of models describing the hysteresis of the soil water retention characteristic were successfully tested on soil cores under controlled laboratory conditions. However, its relevance under field conditions under natural forcings has rarely been investigated. In practice, the modeling of field soils usually neglects the hysteretic nature of soil hydraulic properties. In this study, long-term observations of water content and matric potential in lysimeters of the lysimeter network TERENO-SoilCan are presented, clearly demonstrating the hysteretic behavior of field soils. We propose a classification into three categories related to different time scales. Based on synthetic and long-term monitoring data, three different models of hysteresis were applied to data sets showing different degrees of hysteresis. We found no single model to be superior to the others. The model ranking depended on the degree of hysteresis. All models were able to reflect the general structure of hysteresis in most cases but failed to reproduce the detailed trajectories of state variables especially under highly transient conditions. As an important result we found that the temporal dynamics of wetting and drying significantly affects these trajectories which should be accounted for in future model concepts.

  7. A comparison of refuse attenuation in laboratory and field scale lysimeters.

    PubMed

    Youcai, Zhao; Luochun, Wang; Renhua, Hua; Dimin, Xu; Guowei, Gu

    2002-01-01

    For this study, small and middle scale laboratory lysimeters, and a large scale field lysimeter in situ in Shanghai Refuse Landfill, with refuse weights of 187,600 and 10,800,000 kg, respectively, were created. These lysimeters are compared in terms of leachate quality (pH, concentrations of COD, BOD and NH3-N), refuse composition (biodegradable matter and volatile solid) and surface settlement for a monitoring period of 0-300 days. The objectives of this study were to explore both the similarities and disparities between laboratory and field scale lysimeters, and to compare degradation behaviors of refuse at the intensive reaction phase in the different scale lysimeters. Quantitative relationships of leachate quality and refuse composition with placement time show that degradation behaviors of refuse seem to depend heavily on the scales of the lysimeters and the parameters of concern, especially in the starting period of 0-6 months. However, some similarities exist between laboratory and field lysimeters after 4-6 months of placement because COD and BOD concentrations in leachate in the field lysimeter decrease regularly in a parallel pattern with those in the laboratory lysimeters. NH3-N, volatile solid (VS) and biodegradable matter (BDM) also gradually decrease in parallel in this intensive reaction phase for all scale lysimeters as refuse ages. Though the concrete data are different among the different scale lysimeters, it may be considered that laboratory lysimeters with sufficient scale are basically applicable for a rough simulation of a real landfill, especially for illustrating the degradation pattern and mechanism. Settlement of refuse surface is roughly proportional to the initial refuse height. PMID:11942702

  8. Annual Report for Gravity Collection Lysimeter Monitoring Plan - ERDF Cells 5 and 6

    SciTech Connect

    W.E. Remsen

    2006-12-21

    The objectives of the Annual Report are to: 1) describe changes in the volume of liquid seen in each lysimeter, 2) describe concentrations and changes or trends in the concentrations of leachate-indicator constituents in any liquids accumulated in each lysimeter, 3) summarize the finding in regard to the presence or absence of leachate in each lysimeter, 4) make recommendations, if any, limited to vadose-zone study-related variables. The data and analyses contained in this report reflect the initial characterization of construction and consolidation water in Cells 5 and 6 lysimeters.

  9. Modified sulfur cement solidification of low-level wastes

    SciTech Connect

    Not Available

    1985-10-01

    This topical report describes the results of an investigation on the solidification of low-level radioactive wastes in modified sulfur cement. The work was performed as part of the Waste Form Evaluation Program, sponsored by the US Department of Energy's Low-Level Waste Management Program. Modified sulfur cement is a thermoplastic material developed by the US Bureau of Mines. Processing of waste and binder was accomplished by means of both a single-screw extruder and a dual-action mixing vessel. Waste types selected for this study included those resulting from advanced volume reduction technologies (dry evaporator concentrate salts and incinerator ash) and those which remain problematic for solidification using contemporary agents (ion exchange resins). Process development studies were conducted to ascertain optimal process control parameters for successful solidification. Maximum waste loadings were determined for each waste type and method of processing. Property evaluation testing was carried out on laboratory scale specimens in order to compare with waste form performance for other potential matrix materials. Waste form property testing included compressive strength, water immersion, thermal cycling and radionuclide leachability. Recommended waste loadings of 40 wt. % sodium sulfate and boric acid salts and 43 wt. % incinerator ash, which are based on processing and performance considerations, are reported. Solidification efficiencies for these waste types represent significant improvements over those of hydraulic cements. Due to poor waste form performance, incorporation of ion exchange resin waste in modified sulfur cement is not recommended.

  10. Formation of secondary minerals in a lysimeter approach - A mineral-microbe interaction

    NASA Astrophysics Data System (ADS)

    Schäffner, F.; Merten, D.; De Giudici, G.; Beyer, A.; Akob, D. M.; Ricci, P. C.; Küsel, K.; Büchel, G.

    2012-04-01

    Heavy metal contamination of large areas due to uranium mining operations poses a serious long-term environmental problem. In the Ronneburg district (eastern Thuringia, Germany), leaching of low grade uranium bearing ores (uranium content < 300 g/t) occurred from 1972 to 1990 using acid mine drainage (AMD; pH 2.7-2.8) and diluted sulphuric acid (10 g/l). Secondary mineral phases like birnessite, todorokite and goethite occur within a natural attenuation process associated with enrichment of heavy metals, especially Cd, Ni, Co, Cu and Zn due to a residual contamination even after remediation efforts. To reveal the processes of secondary mineral precipitation in the field a laboratory lysimeter approach was set up under in situ-like conditions. Homogenized soil from the field site and pure quartz sand were used as substrates. In general, in situ measurements of redox potentials in the substrates showed highly oxidizing conditions (200-750 mV). Water was supplied to the lysimeter from below via a mariottés bottle containing contaminated groundwater from the field. Evaporation processes were allowed, providing a continuous flow of water. This led to precipitation of epsomite and probably aplowite on the top layer of substrate, similar to what is observed in field investigations. After 4 weeks, the first iron and manganese bearing secondary minerals became visible. Soil water samples were used to monitor the behaviour of metals within the lysimeter. Saturation indices (SI) for different secondary minerals were calculated with PHREEQC. The SI of goethite showed oversaturation with respect to the soil solution. SEM-EDX analyses and IR spectroscopy confirmed the formation of goethite. Geochemical data revealed that goethite formation was mainly dominated by Eh/pH processes and that heavy metals, e.g. Zn and U, could be enriched in this phase. Although Eh/pH data does not support formation of manganese minerals, Mn(II)-oxidizing bacteria (MOB) could be isolated from field

  11. Screening Experiments for Removal of Low-Level Tritiated Water

    SciTech Connect

    Kim, Yun Mi; Baney, Ronald; Powers, Kevin; Koopman, Ben; Tulenko, James

    2005-03-15

    Screening experiments for low levels of tritiated water (HTO) remediation based upon selective adsorption/desorption mechanisms utilizing equilibrium isotope effects have been carried out. Several organic and inorganic high surface area materials were investigated to assess their ability to selectively adsorb low concentrations of HTO. Ion-exchange resins with cation functionalities, chitosan, sodium alginate, and several inorganic media modified with metal cations exhibited promising results. Biomaterials, for example, chitosan and modified alginate, demonstrated positive results. Based on the literature and our preliminary testing, we postulate four possible mechanisms for selected tritium adsorption: hydrogen ion exchange, HTO coordination with surface cation sites, hydrogen bonding to surface basic sites, and secondary hydrogen bonding (structural water) in fine pores.

  12. Luminous fabric devices for wearable low-level light therapy

    PubMed Central

    Shen, Jing; Chui, Chunghin; Tao, Xiaoming

    2013-01-01

    In this paper, a flexible luminous fabric device was developed and investigated for wearable three-dimensionally fitted low-level light therapy. The fabric device exhibited excellent optical and thermal properties. Its optical power density and operating temperature were stable during usage for 10 hours. In vitro experiments demonstrated a significant increase in collagen production in human fibroblast irradiated by the fabric device, compared with the fibroblast without light irradiation. A series of tests were conducted for the safety of the fabric for human skin contact according to ISO standard ISO 10993-1:2003. The results showed that there was no potential hazard when the luminous fabrics were in direct contact with human skin. PMID:24409391

  13. Low-level light therapy (LLLT) for cosmetics and dermatology

    NASA Astrophysics Data System (ADS)

    Sawhney, Mossum K.; Hamblin, Michael R.

    2014-02-01

    Over the last few years, low-level laser (light) therapy (LLLT) has been demonstrated to be beneficial to the field of aesthetic medicine, specifically aesthetic dermatology. LLLT encompasses a broad spectrum of procedures, primarily cosmetic, which provide treatment options for a myriad of dermatological conditions. Dermatological disorders involving inflammation, acne, scars, aging and pigmentation have been investigated with the assistance of animal models and clinical trials. The most commercially successful use of LLLT is for managing alopecia (hair loss) in both men and women. LLLT also seems to play an influential role in procedures such as lipoplasty and liposuction, allowing for noninvasive and nonthermal methods of subcutaneous fat reduction. LLLT offers a means to address such conditions with improved efficacy versatility and no known side-effects; however comprehensive literature reports covering the utility of LLLT are scarce and thus the need for coverage arises.

  14. Field Lysimeter Test Facility status report IV: FY 1993

    SciTech Connect

    Gee, G.W.; Felmy, D.G.; Ritter, J.C.; Campbell, M.D.; Downs, J.L.; Fayer, M.J.; Kirkham, R.R.; Link, S.O.

    1993-10-01

    At the U.S. Department of Energy`s Hanford Site near Richland, Washington, a unique facility, the Field Lysimeter Test Facility (FLTF) is used to measure drainage from and water storage in soil covers. Drainage has ranged from near zero amounts to more than 50% of the applied water, with the amount depending on vegetative cover and soil type. Drainage occurred from lysimeters with coarse soils and gravel covers, but did not occur from capillary barrier-type lysimeters (1.5 m silt loam soil over coarse sands and gravels) except under the most extreme condition tested. For capillary barriers that were irrigated and kept vegetation-free (bare surface), no drainage occurred in 5 of the past 6 years. However, this past year (1992--1993) a record snowfall of 1,425 mm occurred and water storage in the irrigated, bare-surfaced capillary barriers exceeded 500 mm resulting in drainage of more than 30 mm from these barriers. In contrast, capillary barriers, covered with native vegetation (i.e., shrubs and grasses) did not drain under any climatic condition (with or without irrigation). In FY 1994, the FLTF treatments will be increased from 11 to 17 with the addition of materials that will simulate portions of a prototype barrier planned for construction in 1994 at the Hanford Site. The 17 FLTF treatments are designed to test the expected range of surface soil, vegetation, and climatic conditions encountered at the Hanford Site and will assist in evaluating final surface barrier designs for a waste disposal facility.

  15. Twelfth annual US DOE low-level waste management conference

    SciTech Connect

    Not Available

    1990-01-01

    The papers in this document comprise the proceedings of the Department of Energy's Twelfth Annual Low-Level Radioactive Waste Management Conference, which was held in Chicago, Illinois, on August 28 and 29, 1990. General subjects addressed during the conference included: mixed waste, low-level radioactive waste tracking and transportation, public involvement, performance assessment, waste stabilization, financial assurance, waste minimization, licensing and environmental documentation, below-regulatory-concern waste, low-level radioactive waste temporary storage, current challenges, and challenges beyond 1990.

  16. Annual Report for Gravity Collection Lysimeter Monitoring in ERDF Cells 5, 6, 7, an 8, CY 2009

    SciTech Connect

    R.L. Weiss, B.L. Lawrence

    2010-07-08

    The purpose of this annual report is to evaluate the conditions and identify trends to develop Hanford Site specific data on the performance of the lysimeter systems related to the vadose zone monitoring and potential future use of lysimeter systems.

  17. Water balance measurements and simulations of maize plants on lysimeters

    NASA Astrophysics Data System (ADS)

    Heinlein, Florian; Biernath, Christian; Klein, Christian; Thieme, Christoph; Priesack, Eckart

    2016-04-01

    In Central Europe expected major aspects of climate change are a shift of precipitation events and amounts towards winter months, and the general increase of extreme weather events like heat waves or summer droughts. This will lead to strongly changing regional water availability and will have an impact on future crop growth, water use efficiency and yields. Therefore, to estimate future crop yields by growth models accurate descriptions of transpiration as part of the water balance is important. In this study, maize was grown on weighing lysimeters (sowdate: 24 April 2013). Transpiration was determined by sap flow measurement devices (ICT International Pty Ltd, Australia) using the Heat-Ratio-Method: two temperature probes, 0.5 cm above and below a heater, detect a heat pulse and its speed which allows the calculation of sap flow. Water balance simulations were executed with different applications of the model framework Expert-N. The same pedotransfer and hydraulic functions and the same modules to simulate soil water flow, soil heat and nitrogen transport, nitrification, denitrification and mineralization were used. Differences occur in the chosen potential evapotranspiration ETpot (Penman-Monteith ASCE, Penman-Monteith FAO, Haude) and plant modules (SPASS, CERES). In all simulations ETpot is separated into a soil and a plant part using the leaf are index (LAI). In a next step, these parts are reduced by soil water availability. The sum of these parts is the actual evapotranspiration ETact which is compared to the lysimeter measurements. The results were analyzed from Mid-August to Mid-September 2013. The measured sap flow rates show clear diurnal cycles except on rainy days. The SPASS model is able to simulate these diurnal cycles, overestimates the measurements on rainy days and at the beginning of the analyzed period, and underestimates transpiration on the other days. The main reason is an overestimation of potential transpiration Tpot due to too high

  18. Low-Level Waste (LLW) forum meeting report

    SciTech Connect

    1995-12-31

    The Low-Level Radioactive Waste Forum (LLW Forum) is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  19. A PROCESSING METHOD FOR WEIGHING LYSIMETER DATA AND COMPARISON TO MICROMETEOROLOGICAL ETO PREDICTIONS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weighing lysimeters make direct measurements of water loss from a growing crop and the soil surface around a crop (evapotranspiration, ET) and thus provide basic data to validate other ET prediction methods. The objective of this study was the improvement of the lysimeter data processing to eliminat...

  20. WEB-BASED REAL-TIME MONITORING OF LYSIMETER USING WIRELESS SENSOR NETWORK

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Identification of nitrate-nitrogen (NO3-N) in drainage water allows accessing the effectiveness of water quality management. A wick-type lysimeters was used to monitor water flux and NO3-N leached below the root zone under irrigated cropping system. A wireless lysimeter design was proposed and eval...

  1. Annual Report for Gravity Collection Lysimeter Monitoring Plan- ERDF Cells 5 and 6, CY 2008

    SciTech Connect

    R. L. Weiss; D. W. Woolery

    2009-08-25

    The purpose of this annual report is to evaluate the conditions and identify trends to develop Hanford site-specific data on the performance of the lysimeter systems related to the vadose zone monitoring and potential future use of lysimeter systems.

  2. Unsaturated zone moisture and vapor movement induced by temperature variations in asphalt barrier field lysimeters

    SciTech Connect

    Holford, D.J.; Fayer, M.J.

    1990-08-01

    Protective barriers are being considered for use at the Hanford Site to enhance the isolation of radioactive wastes from water, plant, and animal intrusion. Lysimeters were constructed to evaluate the performance of asphalt barrier formulations under natural environmental conditions. These lysimeters were constructed of 1.7-m lengths of PVC pipe that have a diameter of 30 cm. The lysimeters were filled with layers of gravel, coarse sand, and asphalt. The sand and gravel placed under the asphalt barrier were wet when installed. TOUGH was used to conduct simulations to assess the effect of temperature variations on moisture and vapor movement beneath the asphalt layer in field test lysimeters. All variables in TOUGH were converted to double precision so that simulations could be run on a Sun-4 UNIX workstation. A radially symmetric grid was used to simulate the lysimeter. 8 refs., 9 figs.

  3. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1994-08-01

    This report presents a history of commercial low-level radioactive waste disposal in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the last decade to ensure the safe disposal of low-level radioactive waste in the 1990s and beyond. These steps include the issuance of comprehensive State and Federal regulations governing the disposal of low-level radioactive waste, and the enactment of Federal laws making States responsible for the disposal of such waste generated within their borders.

  4. Responses to the low-level-radiation controversy

    SciTech Connect

    Bond, V.P.

    1981-10-07

    Some data sets dealing with the hazards of low-level radiation are discussed. It is concluded that none of these reports, individually or collectively, changes appreciably or even significantly the evaluations of possible low-level radiation effects that have been made by several authoritative national and international groups. (ACR)

  5. Application of Low level Lasers in Dentistry (Endodontic)

    PubMed Central

    Asnaashari, Mohammad; Safavi, Nassimeh

    2013-01-01

    Low level lasers, cold or soft lasers: These lasers do not produce thermal effects on tissues and induce photoreactions in cells through light stimulation which is called photobiostimulation. Power of these lasers is usually under 250mW. The main point differentiating low level lasers and high power ones is the activation of photochemical reactions without heat formation. The most important factor to achieve this light characteristic in lasers is not their power, but their power density for each surfa ceunit (i.e cm2). Density lower than 670mW/cm2, can induce the stimulatory effects of low level lasers without thermal effects. Low level lasers (therapeutic) used today as treatment adjunctive devices in medicine and dentistry. Numerous studies have been performed on the applications of low level lasers in patient pain reduction. Mechanisms of pain reduction with therapeutic lasers and their application are expressed, and the studies realized in this field are presented. PMID:25606308

  6. The Role of Low-Level Laser in Periodontal Surgeries

    PubMed Central

    Sobouti, Farhad; Khatami, Maziar; Heydari, Mohaddase; Barati, Maryam

    2015-01-01

    Treatment protocols with low-level Laser (also called ‘soft laser therapy) have been used in health care systems for more than three decades. Bearing in mind the suitable sub-cellular absorption and the cellular-vascular impacts, low-level laser may be a treatment of choice for soft tissues. Low-level lasers have played crucial and colorful roles in performing periodontal surgeries. Their anti-inflammatory and painless effects have been variously reported in in-vitro studies. In this present review article, searches have been made in Pub Med, Google Scholar, and Science Direct, focusing on the studies which included low-level lasers, flap-periodontal surgeries, gingivectomy, and periodontal graft. The present study has sought to review the cellular impacts of low-level lasers and its role on reducing pain and inflammation following soft tissue surgical treatments. PMID:25987968

  7. The role of low-level laser in periodontal surgeries.

    PubMed

    Sobouti, Farhad; Khatami, Maziar; Heydari, Mohaddase; Barati, Maryam

    2015-01-01

    Treatment protocols with low-level Laser (also called 'soft laser therapy) have been used in health care systems for more than three decades. Bearing in mind the suitable sub-cellular absorption and the cellular-vascular impacts, low-level laser may be a treatment of choice for soft tissues. Low-level lasers have played crucial and colorful roles in performing periodontal surgeries. Their anti-inflammatory and painless effects have been variously reported in in-vitro studies. In this present review article, searches have been made in Pub Med, Google Scholar, and Science Direct, focusing on the studies which included low-level lasers, flap-periodontal surgeries, gingivectomy, and periodontal graft. The present study has sought to review the cellular impacts of low-level lasers and its role on reducing pain and inflammation following soft tissue surgical treatments. PMID:25987968

  8. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1990-10-01

    This report presents a history of commercial low-level radioactive waste management in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the 1980s to ensure the safe disposal of low-level waste in the 1990s and beyond. These steps include the issuance of Title 10 Code of Federal Regulations Part 61, Licensing Requirements for the Land Disposal of Radioactive Waste, the Low-Level Radioactive Waste Policy Act of 1980, the Low-Level Radioactive Waste Policy Amendments Act of 1985, and steps taken by states and regional compacts to establish additional disposal sites. 42 refs., 13 figs., 1 tab.

  9. Low-level microwave irradiation and central cholinergic systems

    SciTech Connect

    Lai, H.; Carino, M.A.; Horita, A.; Guy, A.W. )

    1989-05-01

    Our previous research showed that 45 min of exposure to low-level, pulsed microwaves (2450-MHz, 2-microseconds pulses, 500 pps, whole-body average specific absorption rate 0.6 W/kg) decreased sodium-dependent high-affinity choline uptake in the frontal cortex and hippocampus of the rat. The effects of microwaves on central cholinergic systems were further investigated in this study. Increases in choline uptake activity in the frontal cortex, hippocampus, and hypothalamus were observed after 20 min of acute microwave exposure, and tolerance to the effect of microwaves developed in the hypothalamus, but not in the frontal cortex and hippocampus, of rats subjected to ten daily 20-min exposure sessions. Furthermore, the effects of acute microwave irradiation on central choline uptake could be blocked by pretreating the animals before exposure with the narcotic antagonist naltrexone. In another series of experiments, rats were exposed to microwaves in ten daily sessions of either 20 or 45 min, and muscarinic cholinergic receptors in different regions of the brain were studied by 3H-QNB binding assay. Decreases in concentration of receptors occurred in the frontal cortex and hippocampus of rats subjected to ten 20-min microwave exposure sessions, whereas increase in receptor concentration occurred in the hippocampus of animals exposed to ten 45-min sessions. This study also investigated the effects of microwave exposure on learning in the radial-arm maze. Rats were trained in the maze to obtain food reinforcements immediately after 20 or 45 min of microwave exposure.

  10. Do the Low Levels of Reading Course Material Continue? An Examination in a Forensic Psychology Graduate Program

    ERIC Educational Resources Information Center

    Clump, Michael A.; Doll, Jason

    2007-01-01

    Clump, Bauer, and Bradley (2004) and Burchfield and Sappington (2000) previously found extremely low levels of reading in undergraduate psychology courses. The current study investigated whether these low levels of reading are also found with graduate students, or if this value is altered by only investigating individuals who show continued…

  11. Hanford low-level tank waste interim performance assessment

    SciTech Connect

    Mann, F.M.

    1996-09-16

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single- and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and its performance as early as possible in the project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives.

  12. Hanford low-level tank waste interim performance assessment

    SciTech Connect

    Mann, F.M.

    1997-09-12

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and performance early in the disposal system project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives.

  13. The Field Lysimeter Test Facility (FLTF) at the Hanford Site: Installation and initial tests

    SciTech Connect

    Gee, G.W.; Kirkham, R.R.; Downs, J.L.; Campbell, M.D.

    1989-02-01

    The objectives of this program are to test barrier design concepts and to demonstrate a barrier design that meets established performance criteria for use in isolating wastes disposed of near-surface at the Hanford Site. Specifically, the program is designed to assess how well the barriers perform in controlling biointrusion, water infiltration, and erosion, as well as evaluating interactions between environmental variables and design factors of the barriers. To assess barrier performance and design with respect to infiltration control, field lysimeters and small- and large-scale field plots are planned to test the performance of specific barrier designs under actual and modified (enhanced precipitation) climatic conditions. The Field Lysimeter Test Facility (FLTF) is located in the 600 Area of the Hanford Site just east of the 200 West Area and adjacent to the Hanford Meteorological Station. The FLTF data will be used to assess the effectiveness of selected protective barrier configurations in controlling water infiltration. The facility consists of 14 drainage lysimeters (2 m dia x 3 m deep) and four precision weighing lysimeters (1.5 m x 1.5 m x 1.7 m deep). The lysimeters are buried at grade and aligned in a parallel configuration, with nine lysimeters on each side of an underground instrument chamber. The lysimeters were filled with materials to simulate a multilayer protective barrier system. Data gathered from the FLTF will be used to compare key barrier components and to calibrate and test models for predicting long-term barrier performance.

  14. Influence of tropical seasonal variations on landfill leachate characteristics--results from lysimeter studies.

    PubMed

    Tränkler, J; Visvanathan, C; Kuruparan, P; Tubtimthai, O

    2005-01-01

    Considering the quality of design and construction of landfills in developing countries, little information can be derived from randomly taken leachate samples. Leachate generation and composition under monsoon conditions have been studied using lysimeters to simulate sanitary landfills and open cell settings. In this study, lysimeters were filled with domestic waste, highly organic market waste and pre-treated waste. Results over two subsequent dry and rainy seasons indicate that the open cell lysimeter simulation showed the highest leachate generation throughout the rainy season, with leachate flow in all lysimeters coming to a halt during the dry periods. More than 60% of the precipitation was found in the form of leachate. The specific COD and TKN load discharged from the open cell was 20% and 180% more than that of the sanitary landfill lysimeters. Types of waste material and kind of pre-treatment prior to landfilling strongly influenced the pollutant load. Compared to the sanitary landfill lysimeter filled with domestic waste, the specific COD and TKN load discharged from the pre-treated waste lysimeter accounted for only 4% and 16%, respectively. Considering the local settings of tropical landfills, these results suggest that landfill design and operation has to be adjusted. Leachate can be collected and stored during the rainy season, and recirculation of leachate is recommended to maintain a steady and even accelerated degradation during the prolonged dry season. The open cell approach in combination with leachate recirculation is suggested as an option for interim landfill operations. PMID:16002273

  15. Bibliographic Data on Low-Level Radioactive Waste Documents

    Energy Science and Technology Software Center (ESTSC)

    1995-11-10

    The purpose of the system is to allow users (researchers, policy makers, etc) to identify existing documents on a range of subjects related to low-level radioactive waste management. The software is menu driven.

  16. Mixed Low-Level Radioactive Waste (MLLW) Primer

    SciTech Connect

    W. E. Schwinkendorf

    1999-04-01

    This document presents a general overview of mixed low-level waste, including the regulatory definitions and drivers, the manner in which the various kinds of mixed waste are regulated, and a discussion of the waste treatment options.

  17. SRNL RADIONUCLIDE FIELD LYSIMETER EXPERIMENT: BASELINE CONSTRUCTION AND IMPLEMENTATION

    SciTech Connect

    Roberts, K.; Kaplan, D.; Bagwell, L.; Powell, B.; Almond, P.; Emerson, H.; Hixon, A.; Jablonski, J.; Buchanan, C.; Waterhouse, T.

    2012-10-17

    The purpose of this document is to compile information regarding experimental design, facility design, construction, radionuclide source preparation, and path forward for the ten year Savannah River National Laboratory (SRNL) Radionuclide Field Lysimeter Experiment at the Savannah River Site (SRS). This is a collaborative effort by researchers at SRNL and Clemson University. The scientific objectives of this study are to: Study long-term radionuclide transport under conditions more representative of vadose zone conditions than laboratory experiments; Provide more realistic quantification of radionuclide transport and geochemistry in the vadose zone, providing better information pertinent to radioactive waste storage solutions than presently exists; Reduce uncertainty and improve justification for geochemical models such as those used in performance assessments and composite analyses.

  18. Actual evapotranspiration and precipitation measured by lysimeters: a comparison with eddy covariance and tipping bucket

    NASA Astrophysics Data System (ADS)

    Gebler, S.; Hendricks Franssen, H.-J.; Pütz, T.; Post, H.; Schmidt, M.; Vereecken, H.

    2014-12-01

    This study compares actual evapotranspiration (ETa) measurements by a set of six weighable lysimeters, ETa estimates obtained with the eddy covariance (EC) method, and potential crop evapotranspiration according to FAO (ETc-FAO) for the Rollesbroich site in the Eifel (Western Germany). The comparison of ETa measured by EC (including correction of the energy balance deficit) and by lysimeters is rarely reported in literature and allows more insight into the performance of both methods. An evaluation of ETa for the two methods for the year 2012 shows a good agreement with a total difference of 3.8% (19 mm) between the ETa estimates. The highest agreement and smallest relative differences (<8%) on monthly basis between both methods are found in summer. ETa was close to ETc-FAO, indicating that ET was energy limited and not limited by water availability. ETa differences between lysimeter, ETc-FAO, and EC were mainly related to differences in grass height caused by harvesting management and the EC footprint. The lysimeter data were also used to estimate precipitation amounts in combination with a filter algorithm for high precision lysimeters recently introduced by Peters et al. (2014). The estimated precipitation amounts from the lysimeter data show significant differences compared to the precipitation amounts recorded with a standard rain gauge at the Rollesbroich test site. For the complete year 2012 the lysimeter records show a 16% higher precipitation amount than the tipping bucket. With the help of an on-site camera the precipitation measurements of the lysimeters were analyzed in more detail. It was found that the lysimeters record more precipitation than the tipping bucket in part related to the detection of rime and dew, which contributes 17% to the yearly difference between both methods. In addition, fog and drizzle explain an additional 5.5% of the total difference. Larger differences are also recorded for snow and sleet situations. During snowfall, the

  19. Actual evapotranspiration and precipitation measured by lysimeters: a comparison with eddy covariance and tipping bucket

    NASA Astrophysics Data System (ADS)

    Gebler, S.; Hendricks Franssen, H.-J.; Pütz, T.; Post, H.; Schmidt, M.; Vereecken, H.

    2015-05-01

    This study compares actual evapotranspiration (ETa) measurements by a set of six weighable lysimeters, ETa estimates obtained with the eddy covariance (EC) method, and evapotranspiration calculated with the full-form Penman-Monteith equation (ETPM) for the Rollesbroich site in the Eifel (western Germany). The comparison of ETa measured by EC (including correction of the energy balance deficit) and by lysimeters is rarely reported in the literature and allows more insight into the performance of both methods. An evaluation of ETa for the two methods for the year 2012 shows a good agreement with a total difference of 3.8% (19 mm) between the ETa estimates. The highest agreement and smallest relative differences (< 8%) on a monthly basis between both methods are found in summer. ETa was close to ETPM, indicating that ET was energy limited and not limited by water availability. ETa differences between lysimeter and EC were mainly related to differences in grass height caused by harvest and the EC footprint. The lysimeter data were also used to estimate precipitation amounts in combination with a filter algorithm for the high-precision lysimeters recently introduced by Peters et al. (2014). The estimated precipitation amounts from the lysimeter data differ significantly from precipitation amounts recorded with a standard rain gauge at the Rollesbroich test site. For the complete year 2012 the lysimeter records show a 16 % higher precipitation amount than the tipping bucket. After a correction of the tipping bucket measurements by the method of Richter (1995) this amount was reduced to 3%. With the help of an on-site camera the precipitation measurements of the lysimeters were analyzed in more detail. It was found that the lysimeters record more precipitation than the tipping bucket, in part related to the detection of rime and dew, which contribute 17% to the yearly difference between both methods. In addition, fog and drizzle explain an additional 5.5% of the total

  20. Effect of exposure on the water balance of two identical lysimeters

    NASA Astrophysics Data System (ADS)

    Hagenau, J.; Meissner, R.; Borg, H.

    2015-01-01

    This study looks at the water balance of two identical weighable lysimeters located right next to each other. They contain the same soil and are managed in the same way. Both were planted with maize. The area around them was planted with maize, too, to ensure that the lysimeters were located inside a crop. The only difference between them was that one side of lysimeter 2 was exposed due to a footpath. At first both yielded similar results. However, as the maize became taller lysimeter 2 began to show consistently more precipitation and drainage. After harvest the differences disappeared again. Since precipitation often falls at an angle, a crop with an exposed side receives more than a crop without one, if the precipitation falls towards the exposed side. The additional precipitation a crop with an exposed side may capture increases with the height of the crop. After harvest this exposure effect therefore disappears completely. Compared to lysimeter 1, lysimeter 2 accumulated >100 mm of additional precipitation during the growth of the maize. After the maize was removed, both crops recorded the same amount of precipitation again. Lysimeter 2 showed more drainage, too, because the additional precipitation led to higher water contents, which in turn caused the water holding capacity of the soil to be exceeded on more days than in the case of lysimeter 1. The difference in actual evapotranspiration was small, because lysimeter 2 was exposed towards west-northwest and therefore received only little more radiation, and because the distribution of the rainfall pattern was such that the additional precipitation led to a similar amount of additional drainage rather than to an increase in the volume of stored water, which could have been consumed by evapotranspiration later. The data clearly illustrate that exposure can significantly alter the water balance of a lysimeter, which makes it inadvisable to extrapolate data obtained under such circumstances to the field. This

  1. Dielectric Properties of Low-Level Liquid Waste

    SciTech Connect

    L. E. Lagos; M. A. Ebadian

    1998-10-20

    The purpose of this study was to develop a data collection containing values for the dielectric properties of various low-level liquid waste (LLLW) simulants measured as a function of frequency, temperature, and composition. The investigation was motivated by current interest in the use of microwave processing for the treatment of radioactive waste. A large volume of transuranic liquid and sludge produced by the U.S. Department of Defense (DOD) during the production of nuclear fiel bars is stored at several U.S. Department of Energy (DOE) sites around the United States. Waste storage and disposal space is scarce, expensive, and must be minimized. Thus, several DOE sites are pursuing the use of microwave heating as a means of achieving volume reduction and solidification of low-level liquid wastes. It is important to know which microwave frequencies should be employed tc achieve the most efficient processing at a range of different temperatures. The dielectric properties of the LLLW simulants can be utilized to determine the optimum frequencies for use with a particular LLLW or with other LLLWS of similar composition. Furthermore, nonlinear thermal processes, such as thermal runaway, which occur in the material being treated cannot be modeled without a knowledge of the temperature dependence of the dielectric properties. Often, this data does not exist; however, when it does, only very limited data near room temperature are available. The data collection generated in this study can be used to predict the behavior of a variety of microwave thermal treatment technologies, which have the potential of substantially reducing the volume of the LLLWS that are currently stored at many DOE sites. This information should help the users of the microwave reduction and solidification technology to optimize microwave processes used in the treatment of LLLW. The microwave reduction and solidification technology has clear advantages over other methods of reducing LLLWS. These

  2. Studying water budget of paved urban sites using weighable lysimeters

    NASA Astrophysics Data System (ADS)

    Rim, Yong-Nam; Nehls, Thomas; Litz, Norbert; Trinks, Steffen; Wessolek, Gerd

    2010-05-01

    Our lysimeter study addresses high-resolution analysis of the water balance of permeable pavements used for sidewalks and streets. Berlin's typical pavers, "Bernburg cobble stone" and "concrete paver" are analysed for actual evaporation, runoff and groundwater recharge. To achieve the reasonable boundary condition realistic seam material were bed in surface construction. The lysimeter bodies, filled with construction sand, stand in 1.5 m deep stainless cave on a scale with a 100g/sec resolution. The seepage water is captured by four suction plates with a suction of 63 hPa. To measure the run-off separately, special gutters are set up directly along the surface edge. This gutter leads the run-off water immediately to a separate discharge pipe and the run-off will be measured with a resolution of 0.0005 mm/sec; no water gets lost within this procedure. A dynamic runoff coefficient could be gained for a span of typical rainfall intensities. We will present runoff coefficients (RC) from both pavements as functions of the rainfall intensity, based on about 40 individual precipitation events. We could show that the rainfall intensity is the best predictor for the runoff behaviour. Concrete pavers can cause runoff with higher RC at lower intensity. However, for intensities > 0.1 mm/min their RCs tend to increase slower than those of mosaic cobble stone pavements. RCs might not be dependent on pavements during strong precipitation events. The measured RC are typical for the rainfall characteristic of Berlin, Germany and should not be used for other climate regions. First, the controlling variable must be identified and incorporated into process based models. Such models are essential for the prediction of urban evaporation so as to develop new urban water and climate management strategies.

  3. Engineered sorbent barriers for low-level waste disposal.

    SciTech Connect

    Freeman, H.D.; Mitchell, S.J.; Buelt, J.L.

    1986-12-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is investigating sorbent materials to prevent the migration of soluble radio nuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Laboratory studies identifield promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent and was adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and local soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow-land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 7 refs., 14 figs., 12 tabs.

  4. Aerobic Denitrifying Bacteria That Produce Low Levels of Nitrous Oxide

    PubMed Central

    Takaya, Naoki; Catalan-Sakairi, Maria Antonina B.; Sakaguchi, Yasushi; Kato, Isao; Zhou, Zhemin; Shoun, Hirofumi

    2003-01-01

    Most denitrifiers produce nitrous oxide (N2O) instead of dinitrogen (N2) under aerobic conditions. We isolated and characterized novel aerobic denitrifiers that produce low levels of N2O under aerobic conditions. We monitored the denitrification activities of two of the isolates, strains TR2 and K50, in batch and continuous cultures. Both strains reduced nitrate (NO3−) to N2 at rates of 0.9 and 0.03 μmol min−1 unit of optical density at 540 nm−1 at dissolved oxygen (O2) (DO) concentrations of 39 and 38 μmol liter−1, respectively. At the same DO level, the typical denitrifier Pseudomonas stutzeri and the previously described aerobic denitrifier Paracoccus denitrificans did not produce N2 but evolved more than 10-fold more N2O than strains TR2 and K50 evolved. The isolates denitrified NO3− with concomitant consumption of O2. These results indicated that strains TR2 and K50 are aerobic denitrifiers. These two isolates were taxonomically placed in the β subclass of the class Proteobacteria and were identified as P. stutzeri TR2 and Pseudomonas sp. strain K50. These strains should be useful for future investigations of the mechanisms of denitrifying bacteria that regulate N2O emission, the single-stage process for nitrogen removal, and microbial N2O emission into the ecosystem. PMID:12788710

  5. Technical issues in licensing low-level radioactive waste facilities

    SciTech Connect

    Junkert, R.

    1993-03-01

    The California Department of Health Service spent two years in the review of an application for a low-level radioactive waste disposal facility in California. During this review period a variety of technical issues had to be evaluated and resolved. One of the first issues was the applicability and use of NRC guidance documents for the development of LLW disposal facilities. Other technical issues that required intensive evaluations included surface water hydrology, seismic investigation, field and numerical analysis of the unsaturated zone, including a water infiltration test. Source term verification became an issue because of one specific isotope that comprised more than 90% of the curies projected for disposal during the operational period. The use of trench liners and the proposed monitoring of the unsaturated zone were reviewed by a highly select panel of experts to provide guidance on the need for liners and to ensure that the monitoring system was capable of monitoring sufficient representative areas for radionuclides in the soil, soil gas, and soil moisture. Finally, concerns about the quality of the preoperational environmental monitoring program, including data, sample collection procedures, laboratory analysis, data review and interpretation and duration of monitoring caused a significant delay in completing the licensing review.

  6. Evaluation of Low-Level Laser Therapy in TMD Patients

    PubMed Central

    Ayyildiz, Simel; Emir, Faruk; Sahin, Cem

    2015-01-01

    Light amplification by stimulated emission of radiation (laser) is one of the most recent treatment modalities in dentistry. Low-level laser therapy (LLLT) is suggested to have biostimulating and analgesic effects through direct irradiation without causing thermal response. There are few studies that have investigated the efficacy of laser therapy in temporomandibular disorders (TMD), especially in reduced mouth opening. The case report here evaluates performance of LLLT with a diode laser for temporomandibular clicking and postoperative findings were evaluated in two cases of TMD patients. First patient had a history of limited mouth opening and pain in temporomandibular joint (TMJ) region since nine months. Second patient's main complaint was his restricted mouth opening, which was progressed in one year. LLLT was performed with a 685 nm red probed diode laser that has an energy density of 6.2 J/cm2, three times a week for one month, and application time was 30 seconds (685 nm, 25 mW, 30 s, 0.02 Hz, and 6.2 J/cm2) (BTL-2000, Portative Laser Therapy Device). The treatment protocol was decided according to the literature. One year later patients were evaluated and there were no changes. This application suggested that LLLT is an appropriate treatment for TMD related pain and limited mouth opening and should be considered as an alternative to other methods. PMID:26587294

  7. Low Level Waste Conceptual Design Adaption to Poor Geological Conditions

    SciTech Connect

    Bell, J.; Drimmer, D.; Giovannini, A.; Manfroy, P.; Maquet, F.; Schittekat, J.; Van Cotthem, A.; Van Echelpoel, E.

    2002-02-26

    Since the early eighties, several studies have been carried out in Belgium with respect to a repository for the final disposal of low-level radioactive waste (LLW). In 1998, the Belgian Government decided to restrict future investigations to the four existing nuclear sites in Belgium or sites that might show interest. So far, only two existing nuclear sites have been thoroughly investigated from a geological and hydrogeological point of view. These sites are located in the North-East (Mol-Dessel) and in the mid part (Fleurus-Farciennes) of the country. Both sites have the disadvantage of presenting poor geological and hydrogeological conditions, which are rather unfavorable to accommodate a surface disposal facility for LLW. The underground of the Mol-Dessel site consists of neogene sand layers of about 180 m thick which cover a 100 meters thick clay layer. These neogene sands contain, at 20 m depth, a thin clayey layer. The groundwater level is quite close to the surface (0-2m) and finally, the topography is almost totally flat. The upper layer of the Fleurus-Farciennes site consists of 10 m silt with poor geomechanical characteristics, overlying sands (only a few meters thick) and Westphalian shales between 15 and 20 m depth. The Westphalian shales are tectonized and strongly weathered. In the past, coal seams were mined out. This activity induced locally important surface subsidence. For both nuclear sites that were investigated, a conceptual design was made that could allow any unfavorable geological or hydrogeological conditions of the site to be overcome. In Fleurus-Farciennes, for instance, the proposed conceptual design of the repository is quite original. It is composed of a shallow, buried concrete cylinder, surrounded by an accessible concrete ring, which allows permanent inspection and control during the whole lifetime of the repository. Stability and drainage systems should be independent of potential differential settlements an d subsidences

  8. Migration and leaching risk of extraneous antimony in three representative soils of China: lysimeter and batch experiments.

    PubMed

    Hou, H; Yao, N; Li, J N; Wei, Y; Zhao, L; Zhang, J; Li, F S

    2013-11-01

    Antimony (Sb) distribution, solubility and mobility onto natural soils of China were studied in lysimeter and batch experiments as a function of physicochemical properties of the soil. An outdoor lysimeter experiment investigated the leaching and migration of Sb in the soils with Sb-polluted topsoil and unpolluted subsoil over a 5month period. Soil solutions were collected by suction cups installed at different depth of lysimeters, and leachates were regularly collected and analyzed for Sb concentrations. The majority of the added Sb was retained in the topsoil layers, but small portions were moved to the sub-layers. Sb concentrations in the soil solutions and leachates ranged from 0-755.5 (6.38±54 on average) μg l(-1) and 0-0.45 (smaller than the detection limit) μg l(-1) respectively, indicating the low solubility of Sb in the soils. Batch experiments were performed in order to determine the sorption capacity and the partition coefficient (Kd). Freundlich isotherm described properly the equilibrium experimental data and results show that the Kd values for Primosol, Isohumosol, Ferrosol equal to 22.5, 87.8, 704 L kg(-1), respectively. These results showed the strong capacity of the soils to retain Sb, and prevent it being leached down the profile. The mobilizable Sb was in the order: Primosol>Isohumosol>Ferrosol. Sb migration in the soils was mainly associated with the exchangeable, carbonate-bound, and metal-organic complex-bound fractions. Health risk assessment indicates that Sb leaching from Ferrosol will not harm to human health through groundwater under the test conditions, while it has certain health risks from the Isohumosol and Primosol. PMID:23931906

  9. Construction and demolition waste: Comparison of standard up-flow column and down-flow lysimeter leaching tests.

    PubMed

    Butera, Stefania; Hyks, Jiri; Christensen, Thomas H; Astrup, Thomas F

    2015-09-01

    Five samples of construction and demolition waste (C&DW) were investigated in order to quantify leaching of inorganic elements under percolation conditions according to two different experimental setups: standardised up-flow saturated columns (<4mm particle size) and unsaturated, intermittent down-flow lysimeters (<40mm particle size). While standardised column tests are meant primarily to provide basic information on characteristic leaching properties and mechanisms and not to reproduce field conditions, the lysimeters were intended to mimic the actual leaching conditions when C&DW is used in unbound geotechnical layers. In practice, results from standardised percolation tests are often interpreted as estimations of actual release from solid materials in percolation scenarios. In general, the two tests yielded fairly similar results in terms of cumulative release at liquid-to-solid ratio (L/S) 10l·kgTS; however, significant differences were observed for P, Pb, Ba, Mg and Zn. Further differences emerged in terms of concentration in the early eluates (L/S<5l·kg(-1)TS) for Al, As, Ba, Cd, Cu, DOC, Mg, Mn, Ni, P, Pb, Sb, Se, Si, Zn. Observed differences between tests are likely to be due to differences in pH related to crushing and exposure of fresh particle surfaces, as well as in equilibrium conditions. In the case of C&DW, the standardised column tests, which are more practical, are considered to acceptably describe cumulative releases at L/S 10l·kg(-1)TS in percolation scenarios. However, when the focus is on estimation of initial concentrations for (for example) risk assessment, data from standardised column tests may not be fully applicable, and data from lysimeters may be used for validation purposes. Se, Cr and, to a lesser extent, SO4 and Sb were leaching from C&DW in critical amounts compared with existing limit values. PMID:26031330

  10. Phytotoxicity testing of lysimeter leachates from aided phytostabilized Cu-contaminated soils using duckweed (Lemna minor L.).

    PubMed

    Marchand, Lilian; Mench, Michel; Marchand, Charlotte; Le Coustumer, Philippe; Kolbas, Aliaksandr; Maalouf, Jean-Paul

    2011-12-01

    Aided phytostabilization of a Cu-contaminated soil was conducted at a wood preservation site located in southwest France using outdoor lysimeters to study leaching from the root zone and leachate ecotoxicity. The effects of Cu-tolerant plants (Agrostis gigantea L. and Populus trichocarpa x deltoides cv. Beaupré) and four amendments were investigated with seven treatments: untreated soil without plants (UNT) and with plants (PHYTO), and planted soils amended with compost (OM, 5% per air-dried soil weight), dolomitic limestone (DL, 0.2%), Linz-Donawitz slag (LDS, 1%), OM with DL (OMDL), and OM with 2% of zerovalent iron grit (OMZ). Total Cu concentrations (mgkg(-1)) in lysimeter topsoil and subsoil were 1110 and 111-153, respectively. Lysimeter leachates collected in year 3 were characterized for Al, B, Ca, Cu, Fe, Mg, Mn, P, K and Zn concentrations, free Cu ions, and pH. Total Cu concentration in leachates (mgL(-1)) ranged from 0.15±0.08 (LDS) to 1.95±0.47 (PHYTO). Plants grown without soil amendment did not reduce total Cu and free Cu ions in leachates. Lemna minor L. was used to assess the leachate phytotoxicity, and based on its growth, the DL, LDS, OM and OMDL leachates were less phytotoxic than the OMZ, PHYTO and UNT ones. The LDS leachates had the lowest Cu, Cu(2+), Fe, and Zn concentrations, but L. minor developed less in these leachates than in a mineral water and a river freshwater. Leachate Mg concentrations were in decreasing order OMDL>DL>PHYTO=OM=LDS>UNT=OMZ and influenced the duckweed growth. PMID:22000292

  11. Case study of a hillside lysimeter with realistic boundary conditions on slope and hillside in an inner alpine area, Switzerland

    NASA Astrophysics Data System (ADS)

    Rey, Emmanuel; Weingartner, Rolf; Liniger, Hanspeter

    2014-05-01

    The MontanAqua project aims to study the water resources management in the region Sierre-Montana (Valais, Switzerland). Thus, datas is of importance to have a precise idea of the water resources. As most of the measuring systems are usually installed at lower altitudes (less than 1500 m asl), water inputs and outputs were monitored through a dense measuring network from the bottom of the Rhone valley to the Plaine Morte glacier (from 550 m asl to 2800 m asl). Weather and discharge stations, but also soil moisture sensors were installed in the key areas of our study region (Sierre-Crans-Motana region, Valais, Switzerland). But Evapotranspiration is a crucial data for water resources management. A hillside lysimeter was built in a typical unirrigated dry meadow to get the actual evapotranspiration on the driest place of the study area. This case study allows us to compare the usual evapotranspiration measurements using soil moisture datas (Seneviratnae et al. 2010). We will calibrate our soil moisture measurements using the lysimeter datas to compute actual evapotranspiration on the whole region. To our knowledge this is the first time a lysimeter is built on slope on an hillside. It was built in September 2010 and the first month were used to set up the lysimeter and all the sensors. Measurements began in 2011 and still occur. The results of the measuring network bring out a north-south and a west-east important rainfall gradients in the region. This mainly means for the region, that the water remain on the upper areas, as higher from Montana, 2000 mm/a of water is coming as rainfall, and less than 800 mm/a fall on the lower area. The lysimeter measured an actual evapotranspiration of 400-440 mm/a on 2011-2012, which leaves less than 200 mm/a of water for the grassland/pasture system. As most of the grassland are irrigated, our soil moisture and lysimeter measurements bring out the amount of water necessary for the agriculture in the region for the next year

  12. Low-level radioactive waste regulation: Science, politics and fear

    SciTech Connect

    Burns, M.E.

    1988-01-01

    An inevitable consequence of the use of radioactive materials is the generation of radioactive wastes and the public policy debate over how they will be managed. In 1980, Congress shifted responsibility for the disposal of low-level radioactive wastes from the federal government to the states. This act represented a sharp departure from more than 30 years of virtually absolute federal control over radioactive materials. Though this plan had the enthusiastic support of the states in 1980, it now appears to have been at best a chimera. Radioactive waste management has become an increasingly complicated and controversial issue for society in recent years. This book discusses only low-level wastes, however, because Congress decided for political reasons to treat them differently than high-level wastes. The book is based in part on three symposia sponsored by the division of Chemistry and the Law of the American Chemical Society. Each chapter is derived in full or in part from presentations made at these meetings, and includes: (1) Low-level radioactive wastes in the nuclear power industry; (2) Low-level radiation cancer risk assessment and government regulation to protect public health; and (3) Low-level radioactive waste: can new disposal sites be found.

  13. Laboratory And Lysimeter Experimentation And Transport Modeling Of Neptunium And Strontium In Savannah River Site Sediments

    SciTech Connect

    Kaplan, Daniel I.; Powell, B. A.; Miller, Todd J.

    2012-09-24

    The Savannah River Site (SRS) conducts performance assessment (PA) calculations to determine the appropriate amount of low-level radiological waste that can be safely disposed on site. Parameters are included in these calculations that account for the interaction between the immobile solid phase and the mobile aqueous phase. These parameters are either the distribution coefficient (K{sub d} value) or the apparent solubility value (K{sub sp}). These parameters are readily found in the literature and are used throughout the DOE complex. One shortcoming of K{sub d} values is that they are only applicable to a given set of solid and aqueous phase conditions. Therefore, a given radionuclide may have several K{sub d} values as it moves between formations and comes into contact with different solids and different aqueous phases. It is expected that the K{sub d} construct will be appropriate to use for a majority of the PA and for a majority of the radionuclides. However, semi-mechanistic models would be more representative in isolated cases where the chemistry is especially transitory or the radionuclide chemistry is especially complex, bringing to bear multiple species of varying sorption tendencies to the sediment. Semi-mechanistic models explicitly accommodate the dependency of K{sub d} values, or other sorption parameters, on contaminant concentration, competing ion concentrations, pH-dependent surface charge on the adsorbent, and solute species distribution. Incorporating semi-mechanistic concepts into geochemical models is desirable to make the models more robust and technically defensible. Furthermore, these alternative models could be used to augment or validate a Kd?based DOE Order 435.1 Performance Assessment. The objectives of this study were to: 1) develop a quantitative thermodynamically-based model for neptunium sorption to SRS sediments, and 2) determine a sorption constant from an SRS 11-year lysimeter study. The modeling studies were conducted with

  14. Low Level Laser Therapy: A Panacea for oral maladies

    PubMed Central

    Kathuria, Vartika; Kalra, Gauri

    2015-01-01

    Aim: To review the applications of low level laser therapy on various soft and hard oral tissues. A variety of therapeutic effects of Low Level Laser Therapy have been reported on a broad range of disorders. It has been found amenably practical in dental applications including soft as well as hard tissues of the oral cavity. LLLT has been found to be efficient in acceleration of wound healing, enhanced remodelling and bone repair, regeneration of neural cells following injury, pain attenuation, endorphin release stimulation and modulation of immune system. The aforementioned biological processes induced by Low level lasers have been effectively applied in treating various pathological conditions in the oral cavity. With is article, we attempt to review the possible application of Low Laser Therapy in the field of dentistry. PMID:26557737

  15. Commission operation. National Low-Level Radioactive Waste Management Program

    NASA Astrophysics Data System (ADS)

    1984-09-01

    Since Congress enacted the Low-Level Radioactive Waste Policy Act, the states have prepared to meet their responsibilities for management of low-level radioactive waste by entering into regional compacts. This option document is intended to provide a framework for the operation of a compact commission formed as the governing body of a low-level radioactive waste compact. The document is designed to be easily modified to meet the needs of various regional compacts. The ideas and format presented were taken in general from the Federal Administrative procedures Act, various state administrative procedures, and the state regulatory agencies' rules of procedure. Requirements of filing, time frames, and standard language are written from a legal perspective.

  16. Remote-Handled Low Level Waste Disposal Project Alternatives Analysis

    SciTech Connect

    David Duncan

    2010-10-01

    This report identifies, evaluates, and compares alternatives for meeting the U.S. Department of Energy’s mission need for management of remote-handled low-level waste generated by the Idaho National Laboratory and its tenants. Each alternative identified in the Mission Need Statement for the Remote-Handled Low-Level Waste Treatment Project is described and evaluated for capability to fulfill the mission need. Alternatives that could meet the mission need are further evaluated and compared using criteria of cost, risk, complexity, stakeholder values, and regulatory compliance. The alternative for disposal of remote-handled low-level waste that has the highest confidence of meeting the mission need and represents best value to the government is to build a new disposal facility at the Idaho National Laboratory Site.

  17. Modelling of a Tracer experiment (Bromide) at the lysimeter Wagna/Austria with MIKE-SHE

    NASA Astrophysics Data System (ADS)

    Reszler, Christian; Fank, Johann

    2015-04-01

    Data of a tracer experiment with Bromide at one of the three lysimeters in Wagna/Austria are used to test the unsaturated zone solute transport model in MIKE-SHE. On April 4th, 2005 50 mg/l of Bromide were applied on the lysimeter operated with conventional farming. At this time the lysimeter was covered with bare soil until the start of the cultivation of pumpkin one month later. Concentrations at the lysimeter bottom (180 cm depth) were measured and, after break-through, plant uptake was measured to quantify mass recovery. The model using the Richards-Van Genuchten-Mualem approach is setup by comprehensive data of vegetation and soil hydraulic properties available at the lysimeter. Water movement simulation in the unsaturated zone is tested against measured seepage rates at the lysimeter bottom and soil water contents in different soil depths in a period of five years. A sensitivity study shows that, particularly in the quaternary gravel zone two different parameter sets are necessary to represent the different dynamics of water content and seepage. With both two sets the general dynamics of the tracer experiment are simulated well. However, the early rapid rise of the measured concentrations could not be represented by either parameter set, which indicates a complex pore system consisting of different flow paths in the gravel zone, e.g., a system of matrix flow and macro-pore flow.

  18. Low level laser therapy reduces inflammation in activated Achilles tendinitis

    NASA Astrophysics Data System (ADS)

    Bjordal, Jan M.; Iversen, Vegard; Lopes-Martins, Rodrigo Alvaro B.

    2006-02-01

    Objective: Low level laser therapy (LLLT) has been forwarded as therapy for osteoarthritis and tendinopathy. Results in animal and cell studies suggest that LLLT may act through a biological mechanism of inflammatory modulation. The current study was designed to investigate if LLLT has an anti-inflammatory effect on activated tendinitis of the Achilles tendon. Methods: Seven patients with bilateral Achilles tendonitis (14 tendons) who had aggravated symptoms by pain-inducing activity immediately prior to the study. LLLT (1.8 Joules for each of three points along the Achilles tendon with 904nm infrared laser) and placebo LLLT were administered to either Achilles tendons in a random order to which patients and therapist were blinded. Inflammation was examined by 1) mini-invasive microdialysis for measuring the concentration of inflammatory marker PGE II in the peritendinous tissue, 2) ultrasound with Doppler measurement of peri- and intratendinous blood flow, 3) pressure pain algometry and 4) single hop test. Results: PGE 2- levels were significantly reduced at 75, 90 and 105 minutes after active LLLT compared both to pre-treatment levels (p=0.026) and to placebo LLLT (p=0.009). Changes in pressure pain threshold (PPT) were significantly different (P=0.012) between groups. PPT increased by a mean value of 0.19 kg/cm2 [95%CI:0.04 to 0.34] after treatment in the active LLLT group, while pressure pain threshold was reduced by -0.20 kg/cm2 [95%CI:-0.45 to 0.05] after placebo LLLT. Conclusion: LLLT can be used to reduce inflammatory musculskeletal pain as it reduces inflammation and increases pressure pain threshold levels in activity-induced pain episodes of Achilles tendinopathy.

  19. A robotic inspector for low-level radioactive waste

    SciTech Connect

    Byrd, J.S.; Pettus, R.O.

    1996-06-01

    The Department of Energy has low-level radioactive waste stored in warehouses at several facilities. Weekly visual inspections are required. A mobile robot inspection system, ARIES (Autonomous Robotic Inspection Experimental System), has been developed to survey and inspect the stored drums. The robot will travel through the three- foot wide aisles of drums stacked four high and perform a visual inspection, normally performed by a human operator, making decisions about the condition of the drums and maintaining a database of pertinent information about each drum. This mobile robot system will improve the quality of inspection, generate required reports, and relieve human operators from low-level radioactive exposure.

  20. Modeling and low-level waste management: an interagency workshop

    SciTech Connect

    Little, C.A.; Stratton, L.E.

    1980-01-01

    The interagency workshop on Modeling and Low-Level Waste Management was held on December 1-4, 1980 in Denver, Colorado. Twenty papers were presented at this meeting which consisted of three sessions. First, each agency presented its point of view concerning modeling and the need for models in low-level radioactive waste applications. Second, a larger group of more technical papers was presented by persons actively involved in model development or applications. Last of all, four workshops were held to attempt to reach a consensus among participants regarding numerous waste modeling topics. Abstracts are provided for the papers presented at this workshop.

  1. Immobilized low-level waste disposal options configuration study

    SciTech Connect

    Mitchell, D.E.

    1995-02-01

    This report compiles information that supports the eventual conceptual and definitive design of a disposal facility for immobilized low-level waste. The report includes the results of a joint Westinghouse/Fluor Daniel Inc. evaluation of trade-offs for glass manufacturing and product (waste form) disposal. Though recommendations for the preferred manufacturing and disposal option for low-level waste are outside the scope of this document, relative ranking as applied to facility complexity, safety, remote operation concepts and ease of retrieval are addressed.

  2. GRABGAM Analysis of Ultra-Low-Level HPGe Gamma Spectra

    SciTech Connect

    Winn, W.G.

    1999-07-28

    The GRABGAM code has been used successfully for ultra-low level HPGe gamma spectrometry analysis since its development in 1985 at Savannah River Technology Center (SRTC). Although numerous gamma analysis codes existed at that time, reviews of institutional and commercial codes indicated that none addressed all features that were desired by SRTC. Furthermore, it was recognized that development of an in-house code would better facilitate future evolution of the code to address SRTC needs based on experience with low-level spectra. GRABGAM derives its name from Gamma Ray Analysis BASIC Generated At MCA/PC.

  3. A preliminary evaluation of alternatives for disposal of INEL low-level waste and low-level mixed waste

    SciTech Connect

    Smith, T.H.; Roesener, W.S.; Jorgenson-Waters, M.J.

    1993-07-01

    The Mixed and Low-Level Waste Disposal Facility (MLLWDF) project was established in 1992 by the US Department of Energy Idaho Operations Office to provide enhanced disposal capabilities for Idaho National Engineering Laboratory (INEL) low-level mixed waste and low-level waste. This Preliminary Evaluation of Alternatives for Disposal of INEL Low-Level Waste and Low-Level Mixed Waste identifies and evaluates-on a preliminary, overview basis-the alternatives for disposal of that waste. Five disposal alternatives, ranging from of no-action`` to constructing and operating the MLLWDF, are identified and evaluated. Several subalternatives are formulated within the MLLWDF alternative. The subalternatives involve various disposal technologies as well as various scenarios related to the waste volumes and waste forms to be received for disposal. The evaluations include qualitative comparisons of the projected isolation performance for each alternative, and facility, health and safety, environmental, institutional, schedule, and rough order-of-magnitude life-cycle cost comparisons. The performance of each alternative is evaluated against lists of ``musts`` and ``wants.`` Also included is a discussion of other key considerations for decisionmaking. The analysis of results indicated further study is necessary to obtain the best estimate of long-term future waste volume and characteristics from the INEL Environmental Restoration activities and the expanded INEL Decontamination and Decommissioning Program.

  4. Transportation and disposal configuration for DOE-managed low-level and mixed low-level waste

    SciTech Connect

    Johnsen, T.

    1993-06-01

    This report briefly examines the current U.S. Department of Energy complex-wide configuration for transportation and disposal of low-level and mixed low-level waste, and also retraces the historical sequence of events and rationale that has guided its development. The study determined that Nevada Test Site and the Hanford Site are the only two sites that currently provide substantial disposal services for offsite low-level waste generators. It was also determined that mixed low-level waste shipments are infrequent and are generally limited to shipments to offsite commercial treatment facilities or other Department of Energy sites for storage. The current alignment of generator to disposal site for low-level waste shipments is generally consistent with the programmatic mission of the generator; that is, defense-generated waste is shipped to the Nevada Test Site and research-generated waste is transported to the Hanford Site. The historical development of the current configuration was resurrected by retrieving Department of Energy documentation and interviewing both current and former department and contractor personnel. According to several accounts, the basic framework of the system was developed during the late 1970s, and was reportedly based on the ability of the disposal site to manage a given waste form. Documented evidence to support this reasoning, however, could not be uncovered.

  5. Central nervous system transplantation benefited by low-level laser irradiation

    NASA Astrophysics Data System (ADS)

    Rochkind, S.; Lubart, Rachel; Wollman, Yoram; Simantov, Rabi; Nissan, Moshe; Barr-Nea, Lilian

    1990-06-01

    Effect of low-level laser irradiation on the central nervous system transplantation is reported. Ernbryonal brain allografts were transplanted into the brain of 20 adult rats and peripheral nerve graft transplanted into the severely injured spinal cord of 16 dogs. The operated wound of 10 rats and 8 dogs were exposed daily for 21 days to lowpower laser irradiation CW HeNe laser (35 mW, 632.8 run, energy density of 30 J/cm2 at each point for rats and 70 J/cm2 at each point for dogs). This study shows that (i) the low-level laser irradiation prevents extensive glial scar formation (a limiting factor in CNS regeneration) between embryonal transplants and host brain; (ii) Dogs made paraplegic by spinal cord injury were able to walk 3-6 months later. Recovery of these dogs was effected by the implantation of a fragment of autologous sciatic nerve at the site of injury and subsequently exposing the dogs to low-level laser irradiation. The effect of laser irradiation on the embryonal nerve cells grown in tissue culture was also observed. We found that low-level laser irradiation induced intensive migration of neurites outward of the aggregates 15-22 The results of the present study and our previous investigations suggest that low-level laser irradiation is a novel tool for treatment of peripheral and central nervous system injuries.

  6. Effect of photon energy in collagen generation by interstitial low level laser stimulation

    NASA Astrophysics Data System (ADS)

    Jun, Eunkwon; Ha, Myungjin; Lee, Sangyeob; Radfar, Edalat; Park, Jihoon; Jung, Byungjo

    2015-03-01

    Although the mechanism of low level laser therapy (LLLT) is unclear, many studies demonstrated the positive clinical performance of LLLT for skin rejuvenation. An increase in dermal collagen plays an important role in skin rejuvenation and wound healing. This study aimed to investigate collagen generation after interstitial low level laser stimulation (ILLS). Rabbits were divided into two groups: surfacing irradiation and minimally invasive irradiation. 660nm diode laser of 20mW with 10J, 13J and 15J was applied to the backside of rabbits. Collagen formation was evaluated with ultrasound skin scanner every 12 hours. Results shows that ILLS groups have denser collagen density than surfacing groups.

  7. Forearm Muscle Oxygenation Decreases During Low Levels of Brief, Isometric Contraction

    NASA Technical Reports Server (NTRS)

    Murthy Gita; Kahan, N. J.; Hargens, Alan R.; Rempel, D. M.; Hargens, Murthy G. (Technical Monitor)

    1997-01-01

    Regional muscle pain syndromes can be caused by repeated and sustained exertion of a specific muscle. Such exertion may elevate local tissue fluid pressure, reduce blood flow and tissue oxygenation (TO2), and cause fatigue, pain and functional deficits of the Involved muscle. Low levels (less than 20% maximum voluntary contraction (MVC)) of prolonged static contraction of the upper extremity are common In many occupational settings and May cause fatigue. The purpose of our Investigation was to determine whether TO2 decreases significantly at low levels of static contraction of the extensor carpi radialis brevis (ECRB).

  8. Utilization of critical periods during development to study the effects of low levels of environmental agents

    SciTech Connect

    Russell, L. B.

    1980-01-01

    Careful definition of critical periods in the development of selected characters can result in experimental systems that may be highly useful in studying risk at low levels of exposure. Three examples are presented. Epidemiological investigations can lose much of their value unless critical periods are known for the end points being studied.

  9. LOW-LEVEL CARBON MONOXIDE EXPOSURE AND WORK CAPACITY AT 1600 METERS

    EPA Science Inventory

    At sea level, low-level carbon monoxide (CO) exposure impairs exercise performance. To determine if altitude residence at 1600 m augments this CO effect, two studies of graded treadmill work capacity were done. The Initial Study investigated nine, non-smoking male subjects breath...

  10. Mixed and Low-Level Waste Treatment Facility project

    SciTech Connect

    Not Available

    1992-04-01

    Mixed and low-level wastes generated at the Idaho National Engineering Laboratory (INEL) are required to be managed according to applicable State and Federal regulations, and Department of Energy Orders that provide for the protection of human health and the environment. The Mixed and Low-Level Waste Treatment Facility Project was chartered in 1991, by the Department of Energy to provide treatment capability for these mixed and low-level waste streams. The first project task consisted of conducting engineering studies to identify the waste streams, their potential treatment strategies, and the requirements that would be imposed on the waste streams and the facilities used to process them. The engineering studies, initiated in July 1991, identified 37 mixed waste streams, and 55 low-level waste streams. This report documents the waste stream information and potential treatment strategies, as well as the regulatory requirements for the Department of Energy-owned treatment facility option. The total report comprises three volumes and two appendices. This report consists of Volume 1, which explains the overall program mission, the guiding assumptions for the engineering studies, and summarizes the waste stream and regulatory information, and Volume 2, the Waste Stream Technical Summary which, encompasses the studies conducted to identify the INEL's waste streams and their potential treatment strategies.

  11. Low-Level Waste Disposal Alternatives Analysis Report

    SciTech Connect

    Timothy Carlson; Kay Adler-Flitton; Roy Grant; Joan Connolly; Peggy Hinman; Charles Marcinkiewicz

    2006-09-01

    This report identifies and compares on-site and off-site disposal options for the disposal of contract-handled and remote-handled low-level waste generated by the Idaho National Laboratory and its tenants. Potential disposal options are screened for viability by waste type resulting in a short list of options for further consideration. The most crediable option are selected after systematic consideration of cost, schedule constraints, and risk. In order to holistically address the approach for low-level waste disposal, options are compiled into comprehensive disposal schemes, that is, alternative scenarios. Each alternative scenario addresses the disposal path for all low-level waste types over the period of interest. The alternative scenarios are compared and ranked using cost, risk and complexity to arrive at the recommended approach. Schedule alignment with disposal needs is addressed to ensure that all waste types are managed appropriately. The recommended alternative scenario for the disposal of low-level waste based on this analysis is to build a disposal facility at the Idaho National Laboratory Site.

  12. Teaching Low-Level Adult ESL Learners. ERIC Digest.

    ERIC Educational Resources Information Center

    Holt, Grace Massey

    In recent years, the English-as-a-Second-Language (ESL) teaching profession has made discoveries about teaching beginning or low-level adult learners (those with little or no schooling in their native languages, learners who may not be familiar with the Roman alphabet, those with learning disabilities, and those literate in their native languages…

  13. Low-level radioactive waste disposal facility closure

    SciTech Connect

    White, G.J.; Ferns, T.W.; Otis, M.D.; Marts, S.T.; DeHaan, M.S.; Schwaller, R.G.; White, G.J. )

    1990-11-01

    Part I of this report describes and evaluates potential impacts associated with changes in environmental conditions on a low-level radioactive waste disposal site over a long period of time. Ecological processes are discussed and baselines are established consistent with their potential for causing a significant impact to low-level radioactive waste facility. A variety of factors that might disrupt or act on long-term predictions are evaluated including biological, chemical, and physical phenomena of both natural and anthropogenic origin. These factors are then applied to six existing, yet very different, low-level radioactive waste sites. A summary and recommendations for future site characterization and monitoring activities is given for application to potential and existing sites. Part II of this report contains guidance on the design and implementation of a performance monitoring program for low-level radioactive waste disposal facilities. A monitoring programs is described that will assess whether engineered barriers surrounding the waste are effectively isolating the waste and will continue to isolate the waste by remaining structurally stable. Monitoring techniques and instruments are discussed relative to their ability to measure (a) parameters directly related to water movement though engineered barriers, (b) parameters directly related to the structural stability of engineered barriers, and (c) parameters that characterize external or internal conditions that may cause physical changes leading to enhanced water movement or compromises in stability. Data interpretation leading to decisions concerning facility closure is discussed. 120 refs., 12 figs., 17 tabs.

  14. 77 FR 26991 - Low-Level Radioactive Waste Management Issues

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-08

    ... Volume Reduction and Low-Level Radioactive Waste Management'' (76 FR 50500; August 15, 2011); and the... regulations were published in the Federal Register on December 27, 1982 (47 FR 57446). The rule applies to any... (74 FR 30175; Docket ID NRC-2009-0257), the NRC staff subsequently developed a technical...

  15. Credit WCT. Photographic copy of photograph, low level aerial view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit WCT. Photographic copy of photograph, low level aerial view of Test Stand "D," looking due west, after completion of Dd station installation in 1961. Note Test Stand "D" "neutralization pond" to immediate southeast of tower. (JPL negative no. 384-2997-B, 12 December 1961) - Jet Propulsion Laboratory Edwards Facility, Test Stand D, Edwards Air Force Base, Boron, Kern County, CA

  16. Effects of low levels of radiation on humans

    SciTech Connect

    Auxier, J.A.

    1981-01-01

    The state of knowledge on effects of low-level ionizing radiations on humans is reviewed. Several problems relating to dose thresholds or lack of thresholds for several types of cancer and high LET radiations and the effects of fractionation and dose protection are discussed. (ACR)

  17. Environmentalism and low-level waste-the aftermath

    SciTech Connect

    Pastorelle, P.J.

    1995-05-01

    Radical Environmentalists, anxious to shut down nuclear power, are directing efforts against the disposal of low-level radioactive wastes (contaminated coveralls, tools, paper, plastic, glass, etc.). The rationals is that if nuclear power facilities cannot dispose of their waste streams, eventually they may have to stop operating. This article discusses the political and practical issues surrounding this approach.

  18. Field Lysimeter Test Facility: Second year (FY 1989) test results

    SciTech Connect

    Campbell, M.D.; Gee, G.W.; Kanyid, M.J.; Rockhold, M.L.

    1990-04-01

    The Record of Decision associated with the Hanford Defense Waste Environmental Impact Statement (53 FR 12449-53) commits to an evaluation of the use of protective barriers placed over near-surface wastes. The barrier must protect against wind and water erosion and limit plant and animal intrusion and infiltration of water. Successful conclusion of this program will yield the necessary protective barrier design for near-surface waste isolation. This report presents results from the second year of tests at the FLTF. The primary objective of testing protective barriers at the FLTF was to measure the water budgets within the various barriers and assess the effectiveness of their designs in limiting water intrusion into the zone beneath each barrier. Information obtained from these measurements is intended for use in refining barrier designs. Four elements of water budget were measured during the year: precipitation, evaporation, storage, and drainage. Run-off, which is a fifth element of a complete water budget, was made negligible by a lip on the lysimeters that protrudes 5 cm above the soil surface to prevent run-off. A secondary objective of testing protective barriers at the FLTF was to refine procedures and equipment to support data collection for verification of the computer model needed for long-term projections of barrier performance. 6 refs.

  19. Cadmium leaching from micro-lysimeters planted with the hyperaccumulator Thlaspi caerulescens: experimental findings and modeling.

    PubMed

    Ingwersen, Joachim; Bücherl, Barbara; Neumann, Günter; Streck, Thilo

    2006-01-01

    The use of heavy metal hyperaccumulating plants has the potential to become a promising new technique to remediate contaminated sites. We investigated the role of metal mobilization in the Cd hyperaccumulation of Thlaspi caerulescens (J. & C. Presl, 'Ganges'). In a micro-lysimeter experiment we investigated the dynamics of Cd concentration of leachate as well as Cd removal by plant uptake in four treatments: (i) Control (bare soil), (ii) T. caerulescens, (iii) nonhyperaccumulator Brassica juncea (L.) Czern. ('PI 426308'), and (iv) co-cropping of the hyperaccumulator and nonhyperaccumulator. The experimental findings were analyzed using one- and two-site rate-limited desorption models. Co-cropping of T. caerulescens and B. juncea did not enhance metal uptake by B. juncea. Although Cd uptake of T. caerulescens was 10 times higher than that of B. juncea, the Cd concentration of leachate of the T. caerulescens treatment did not decrease below that of the B. juncea treatment. The Cd depletion in leachate was well reproduced by the two-site rate-limited desorption model. The optimized desorption coefficient was three orders of magnitude higher in the rhizosphere than in the bulk soil. Our results indicate that T. caerulescens accelerates the resupply of Cd from soil pointing to an important role of kinetic desorption in the hyperaccumulation by T. caerulescens. PMID:17071874

  20. Automatic Measurement of Low Level Contamination on Concrete Surfaces

    SciTech Connect

    Tachibana, M.; Itoh, H.; Shimada, T.; Yanagihara, S.

    2002-02-28

    Automatic measurement of radioactivity is necessary for considering cost effectiveness in final radiological survey of building structures in decommissioning nuclear facilities. The RAPID (radiation measuring pilot device for surface contamination) was developed to be applied to automatic measurement of low level contamination on concrete surfaces. The RAPID has a capability to measure contamination with detection limit of 0.14 Bq/cm2 for 60Co in 30 seconds of measurement time and its efficiency is evaluated to be 5 m2/h in a normal measurement option. It was confirmed that low level contamination on concrete surfaces could be surveyed by the RAPID efficiently compared with direct measurement by workers through its actual application.

  1. National Low-Level Waste Management Program Radionuclide Report Series

    SciTech Connect

    J.P. Adams; M.L. Carboneau; W.E. Allred

    1999-02-01

    The National Low Level Waste Management Program at the Idaho National Engineering and Environmental Laboratory has published a report containing key information about selected radionuclides that are most likely to contribute significantly to the radiation exposures estimated from a performance assessment of a low-level radioactive waste (LLW) disposal facility. The information includes physical and chemical characteristics, production means, waste forms, behavior of the radionuclide in soils, plants, groundwater, and air, and biological effects in animals and humans. The radionuclides included in this study comprise all of the nuclides specifically listed in 10CFR61.55, Tables 1 and 2, 3 H, 14 C, 59 Ni, 60 Co, 63 Ni, 90 Sr, 94 Nb, 99 Tc, 129 I, 137 Cs, 241 Pu, and 242 Cm. Other key radionuclides addressed in the report include 237 Np, 238 U, 239 Pu, and 241 Am. This paper summarizes key information contained within this report.

  2. National Low-Level Waste Management Program Radionuclide Report Series

    SciTech Connect

    Adams, James Paul; Carboneau, Michael Leonard; Allred, William Edgar

    1999-03-01

    The National Low Level Waste Management Program at the Idaho National Engineering and Environmental Laboratory has published a report containing key information about selected radionuclides that are most likely to contribute significantly to the radiation exposures estimated from a performance assessment of a low-level radioactive waste (LLW) disposal facility. The information includes physical and chemical characteristics, production means, waste forms, behavior of the radionuclide in soils, plants, groundwater, and air, and biological effects in animals and humans. The radionuclides included in this study comprise all of the nuclides specifically listed in 10CFR61.55, Tables 1 and 2, 3 H, 14 C, 59 Ni, 60 Co, 63 Ni, 90 Sr, 94 Nb, 99 Tc, 129 I, 137 Cs, 241 Pu, and 242 Cm. Other key radionuclides addressed in the report include 237 Np, 238 U, 239 Pu, and 241 Am. This paper summarizes key information contained within this report.

  3. Criticality safety considerations for low-level-waste facilities

    SciTech Connect

    Hopper, C.M.

    1995-04-01

    The nuclear criticality safety for handling and burial of certain special nuclear materials (SNM) at low-level-waste (LLW) facilities is licensed by the US Nuclear Regulatory Commission (NRC). Recently, Oak Ridge National Laboratory (ORNL) staff assisted the NRC Office of Nuclear Material Safety and Safeguards, Low-Level-Waste and Decommissioning Projects Branch, in developing technical specifications for the nuclear criticality safety of {sup 235}U and {sup 235}Pu in LLW facilities. This assistance resulted in a set of nuclear criticality safety criteria that can be uniformly applied to the review of LLW package burial facility license applications. These criteria were developed through the coupling of the historic surface-density criterion with current computational technique to establish safety criteria considering SNM material form and reflector influences. This paper presents a summary of the approach used to establish and to apply the criteria to the licensing review process.

  4. Low-level RF control for the AFEL

    SciTech Connect

    Ziomek, C.; Kinross-Wright, J.; Plato, J.

    1994-09-01

    A limiting factor in the performance of the Los Alamos Advanced Free Electron Laser (AFEL) is the stability of the RF accelerating field. A high-performance low-level RF control system has been implemented that uses analog feedback and digital feed forward to regulate the RF field. This low-level RF control system has achieved long-term amplitude and phase stabilities better than {+-}0.25% and {+-}0.33{degree} respectively. In order to improve the RF field stability further, a detailed system analysis and design is proceeding. Subsystem measurements are being used to model the system performance, predict the performance-limiting components, and determine possible improvements. Results to-date, modeling analyses, and suggested future improvements are presented.

  5. A model for a national low level waste program

    SciTech Connect

    Blankenhorn, James A

    2009-01-01

    A national program for the management of low level waste is essential to the success of environmental clean-up, decontamination and decommissioning, current operations and future missions. The value of a national program is recognized through procedural consistency and a shared set of resources. A national program requires a clear waste definition and an understanding of waste characteristics matched against available and proposed disposal options. A national program requires the development and implementation of standards and procedures for implementing the waste hierarchy, with a specitic emphasis on waste avoidance, minimization and recycling. It requires a common set of objectives for waste characterization based on the disposal facility's waste acceptance criteria, regulatory and license requirements and performance assessments. Finally, a national waste certification program is required to ensure compliance. To facilitate and enhance the national program, a centralized generator services organization, tasked with providing technical services to the generators on behalf of the national program, is necessary. These subject matter experts are the interface between the generating sites and the disposal facility(s). They provide an invaluable service to the generating organizations through their involvement in waste planning prior to waste generation and through championing implementation of the waste hierarchy. Through their interface, national treatment and transportation services are optimized and new business opportunities are identified. This national model is based on extensive experience in the development and on-going management of a national transuranic waste program and management of the national repository, the Waste Isolation Pilot Plant. The Low Level Program at the Savannah River Site also successfully developed and implemented the waste hierarchy, waste certification and waste generator services concepts presented below. The Savannah River Site

  6. Mixed and low-level waste treatment facility project

    SciTech Connect

    Not Available

    1992-04-01

    The technology information provided in this report is only the first step toward the identification and selection of process systems that may be recommended for a proposed mixed and low-level waste treatment facility. More specific information on each technology will be required to conduct the system and equipment tradeoff studies that will follow these preengineering studies. For example, capacity, maintainability, reliability, cost, applicability to specific waste streams, and technology availability must be further defined. This report does not currently contain all needed information; however, all major technologies considered to be potentially applicable to the treatment of mixed and low-level waste are identified and described herein. Future reports will seek to improve the depth of information on technologies.

  7. Low-level waste disposal in highly populated areas

    SciTech Connect

    Kowalski, E.; McCombie, C.; Issler, H.

    1989-11-01

    Nuclear-generated electricity supplies almost 40% of the demand in Switzerland (the rest being hydro-power). Allowing for a certain reserve and assuming an operational life-time of 40 years for each reactor, and taking into account wastes from decommissioning and from medicine, industry and research, the total amount of low-level radioactive waste to be disposed of is about 175,000 m{sup 3}. Since there are no unpopulated areas in Switzerland, and since Swiss Federal Law specifies that the safety of disposal may not depend upon supervision of the repository, no shallow-land burial has been foreseen, even for short-lived low-level waste. Instead, geological disposal in a mined cavern system with access through a horizontal tunnel was selected as the best way of meeting the requirements and ensuring the necessary public acceptance.

  8. The Argonne low level /sup 14/C counting system

    SciTech Connect

    Gray, J.; Rymas, S.J.; Studebaker, L.D.; Yule, H.P.

    1987-01-01

    A low level /sup 14/CO/sub 2/ counting system is described. This system was used to process several thousand CO/sub 2/ samples derived from atmospheric collections at various altitudes. Special features include counter construction utilizing electrolytic copper and shielding with neutron moderating and absorbing paraffin containing sodium metaborate. The effect of steel shielding thickness is shown, and the anticoincidence counters are described. Purification of the CO/sub 2/ for proportional counting is discussed. 5 refs., 3 figs.

  9. Waste Management Facilities cost information for low-level waste

    SciTech Connect

    Shropshire, D.; Sherick, M.; Biadgi, C.

    1995-06-01

    This report contains preconceptual designs and planning level life-cycle cost estimates for managing low-level waste. The report`s information on treatment, storage, and disposal modules can be integrated to develop total life-cycle costs for various waste management options. A procedure to guide the US Department of Energy and its contractor personnel in the use of cost estimation data is also summarized in this report.

  10. Commercial low-level radioactive waste disposal in the US

    SciTech Connect

    Smith, P.

    1995-10-01

    Why are 11 states attempting to develop new low-level radioactive waste disposal facilities? Why is only on disposal facility accepting waste nationally? What is the future of waste disposal? These questions are representative of those being asked throughout the country. This paper attempts to answer these questions in terms of where we are, how we got there, and where we might be going.

  11. Chemical digestion of low level nuclear solid waste material

    DOEpatents

    Cooley, Carl R.; Lerch, Ronald E.

    1976-01-01

    A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230.degree.-300.degree.C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue.

  12. Soil-atmosphere and vadose zone water fluxes at the Wagna - lysimeter: Workflow, models, and results

    NASA Astrophysics Data System (ADS)

    Fank, Johann

    2014-05-01

    A precise knowledge of the water fluxes between the soil-plant system and the atmosphere is of great importance for understanding and modeling water, solute and energy transfer in the soil-plant-atmosphere system. Weighing lysimeters are precise tools to allow the determination of the hydrological cycle components in very short time intervals. Lysimeters with controlled suction at the lower boundary allow estimation of capillary rise and deep water percolation on short time scales. Evapotranspiration, rainfall, and irrigation can be computed from weight changes. In the last decades resolution and precision of the weighing systems have been substantially improved, so that modern lysimeters, resting on weighing cells can reach resolutions of up to 0.01 mm. Nevertheless, a lot of external effects (e.g. from maintenance, surface treatment) and small mechanical disturbances (e.g. caused by wind) became visible in the data. Seepage mass data are affected by water sampling and the emptying process of the seepage water container. Increasing parts of corrected seepage mass data show deep water percolation, decreasing parts in dry weather periods can be interpreted as capillary rise. In the evaluation process of corrected lysimeter mass data every increase in system weight (lysimeter mass + cumulative seepage mass) might be interpreted as rainfall or irrigation, whereas every decrease in system weight is interpreted as evapotranspiration. To apply this concept correctly, the noise in both data sets has to be separated from signals using a filtering routine (e.g. Peters et al., 2013) which is appropriate for any event, including events with low disturbances as well as strong wind and heavy precipitation in small time intervals. Based on the data set from the "Wagna" lysimeter in Austria with a high resolution of the scale (~ 0,015 mm) and very low noise due to low wind velocities for the year 2010 a lysimeter data preparation workflow will be executed: (a) correction of the

  13. Lidar Measurements of Summer Low Level Jet Events over Baltimore

    NASA Astrophysics Data System (ADS)

    Delgado, R.; Weldegaber, M.; Woodman, M.; Seybold, M.; Demoz, B.; McCann, K. J.; Whiteman, D. N.; Hoff, R. M.

    2008-05-01

    Remote sensing of atmospheric aerosols and water vapor, in the lower troposphere, have been carried out at the University of Maryland, Baltimore County (UMBC) by the Atmospheric Lidar Group during summer low level jet events over Maryland for two years and especially during the Water Vapor Variability - Satellite/Sondes (WAVES) campaigns of 2006 and 2007. For lofted layers encountered the aerosol lidar ratio (Sa) was computed to determine the aerosol extinction and subsequently the optical depth. Aerosol stratification and disturbance of nocturnal boundary layer, observed by lidar at UMBC, was confirmed by Maryland Department of the Environment (MDE) wind profiler measurements. The vertical and horizontal distribution of the low level jet was identified with the Weather Research and Forecasting (WRF) model to characterize the nature and possible effects of the incoming low level jet air mass on surface ozone within the boundary layer. Ground measurements from MDE monitoring stations and lidar optical depth are compared to evaluate aerosol loading due to long range transport in the boundary layer.

  14. Low-level radioactive waste technology: a selected, annotated bibliography

    SciTech Connect

    Fore, C.S.; Vaughan, N.D.; Hyder, L.K.

    1980-10-01

    This annotated bibliography of 447 references contains scientific, technical, economic, and regulatory information relevant to low-level radioactive waste technology. The bibliography focuses on environmental transport, disposal site, and waste treatment studies. The publication covers both domestic and foreign literature for the period 1952 to 1979. Major chapters selected are Chemical and Physical Aspects; Container Design and Performance; Disposal Site; Environmental Transport; General Studies and Reviews; Geology, Hydrology and Site Resources; Regulatory and Economic Aspects; Transportation Technology; Waste Production; and Waste Treatment. Specialized data fields have been incorporated into the data file to improve the ease and accuracy of locating pertinent references. Specific radionuclides for which data are presented are listed in the Measured Radionuclides field, and specific parameters which affect the migration of these radionuclides are presented in the Measured Parameters field. In addition, each document referenced in this bibliography has been assigned a relevance number to facilitate sorting the documents according to their pertinence to low-level radioactive waste technology. The documents are rated 1, 2, 3, or 4, with 1 indicating direct applicability to low-level radioactive waste technology and 4 indicating that a considerable amount of interpretation is required for the information presented to be applied. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. Indexes are provide for (1) author(s), (2) keywords, (3) subject category, (4) title, (5) geographic location, (6) measured parameters, (7) measured radionuclides, and (8) publication description.

  15. Mixed and Low-Level Waste Treatment Facility Project

    SciTech Connect

    Not Available

    1992-04-01

    Mixed and low-level wastes generated at the Idaho National Engineering Laboratory (INEL) are required to be managed according to applicable State and Federal regulations, and Department of Energy Orders that provide for the protection of human health and the environment. The Mixed and Low-Level Waste Treatment Facility Project was chartered in 1991, by the Department of Energy to provide treatment capability for these mixed and low-level waste streams. The first project task consisted of conducting engineering studies to identify the waste streams, their potential treatment strategies, and the requirements that would be imposed on the waste streams and the facilities used to process them. This report documents those studies so the project can continue with an evaluation of programmatic options, system tradeoff studies, and the conceptual design phase of the project. This report, appendix B, comprises the engineering design files for this project study. The engineering design files document each waste steam, its characteristics, and identified treatment strategies.

  16. Low-level measurements of tritium in water.

    PubMed

    Villa, M; Manjón, G

    2004-01-01

    Using a liquid scintillation counter, an experimental procedure for measuring low-level activity concentrations of tritium in environmental water has been developed by our laboratory, using the electrolytic tritium enrichment. Additionally, some quality tests were applied in order to assure the goodness of the method. Well-known water samples collected in the Tagus River (West of Spain) and the Danube River (Bulgaria), both affected by nuclear plant releases, were analysed and results were compared to previous data. The analytical procedure was applied to drinking water samples from the public water supply of Seville and mineral waters from different springs in Spain in order to characterize its origin. Due to the very low levels of tritium in the analysed samples, some results were reported as lower than the minimum detectable activity concentration (MDA). However, the count rate of these measurements was over the background count rate of LS counter in all the cases. For that reason, an exhaustive discussion about the meaning of the MDA, using an experimental essay, was made in order to establish a rigorous criterion that leads to a reliable value in the case of low-level measurements. PMID:15177365

  17. Management of low-level radioactive wastes around the world

    SciTech Connect

    Lakey, L.T.; Harmon, K.M.; Colombo, P.

    1985-04-01

    This paper reviews the status of various practices used throughout the world for managing low-level radioactive wastes. Most of the information in this review was obtained through the DOE-sponsored International Program Support Office (IPSO) activities at Pacific Northwest Laboratory (PNL) at Richland, Washington. The objective of IPSO is to collect, evaluate, and disseminate information on international waste management and nuclear fuel cycle activities. The center's sources of information vary widely and include the proceedings of international symposia, papers presented at technical society meetings, published topical reports, foreign trip reports, and the news media. Periodically, the information is published in topical reports. Much of the information contained in this report was presented at the Fifth Annual Participants' Information Meeting sponsored by DOE's Low-Level Waste Management Program Office at Denver, Colorado, in September of 1983. Subsequent to that presentation, the information has been updated, particularly with information provided by Dr. P. Colombo of Brookhaven National Laboratory who corresponded with low-level waste management specialists in many countries. The practices reviewed in this paper generally represent actual operations. However, major R and D activities, along with future plans, are also discussed. 98 refs., 6 tabls.

  18. Greater-confinement disposal of low-level radioactive wastes

    SciTech Connect

    Trevorrow, L.E.; Gilbert, T.L.; Luner, C.; Merry-Libby, P.A.; Meshkov, N.K.; Yu, C.

    1985-01-01

    Low-level radioactive wastes include a broad spectrum of wastes that have different radionuclide concentrations, half-lives, and physical and chemical properties. Standard shallow-land burial practice can provide adequate protection of public health and safety for most low-level wastes, but a small volume fraction (about 1%) containing most of the activity inventory (approx.90%) requires specific measures known as ''greater-confinement disposal'' (GCD). Different site characteristics and different waste characteristics - such as high radionuclide concentrations, long radionuclide half-lives, high radionuclide mobility, and physical or chemical characteristics that present exceptional hazards - lead to different GCD facility design requirements. Facility design alternatives considered for GCD include the augered shaft, deep trench, engineered structure, hydrofracture, improved waste form, and high-integrity container. Selection of an appropriate design must also consider the interplay between basic risk limits for protection of public health and safety, performance characteristics and objectives, costs, waste-acceptance criteria, waste characteristics, and site characteristics. This paper presents an overview of the factors that must be considered in planning the application of methods proposed for providing greater confinement of low-level wastes. 27 refs.

  19. Steam reforming of low-level mixed waste

    SciTech Connect

    Voelker, G.E.; Steedman, W.G.; Chandran, R.R.

    1996-12-31

    The U.S. department of Energy (DOE) is responsible for the treatment and disposal of an inventory of approximately 160,000 tons of Low-Level Mixed Waste (LLMW). Most of this LLMW is stored in drums, barrels and steel boxes at 20 different sites throughout the DOE complex. The basic objective of low-level mixed waste treatment systems is to completely destroy the hazardous constituents and to simultaneously isolate and capture the radionuclides in a superior final waste form such as glass. The DOE is sponsoring the development of advanced technologies that meet this objective while achieving maximum volume reduction, low-life cycle costs and maximum operational safety. ThermoChem, Inc. is in the final stages of development of a steam-reforming system capable of treating a wide variety of DOE low-level mixed waste that meets these objectives. The design, construction, and testing of a nominal 1 ton/day Process Development Unit is described.

  20. Recent progress in low-level gamma imaging

    SciTech Connect

    Mahe, C.; Girones, Ph.; Lamadie, F.; Le Goaller, C.

    2007-07-01

    The CEA's Aladin gamma imaging system has been operated successfully for several years in nuclear plants and during decommissioning projects with additional tools such as gamma spectrometry detectors and dose rate probes. The radiological information supplied by these devices is becoming increasingly useful for establishing robust and optimized decommissioning scenarios. Recent technical improvements allow this gamma imaging system to be operated in low-level applications and with shorter acquisition times suitable for decommissioning projects. The compact portable system can be used in places inaccessible to operators. It is quick and easy to implement, notably for onsite component characterization. Feasibility trials and in situ measurements were recently carried out under low-level conditions, mainly on waste packages and glove boxes for decommissioning projects. This paper describes recent low-level in situ applications. These characterization campaigns mainly concerned gamma emitters with {gamma} energy < 700 keV. In many cases, the localization of hot spots by gamma camera was confirmed by additional measurements such as dose rate mapping and gamma spectrometry measurements. These complementary techniques associated with advanced calculation codes (MCNP, Mercure 6.2, Visiplan and Siren) offer a mobile and compact tool for specific assessment of waste packages and glove boxes. (authors)

  1. Mixed and Low-Level Waste Treatment Facility project

    SciTech Connect

    Not Available

    1992-04-01

    Mixed and low-level wastes generated at the Idaho National Engineering Laboratory (INEL) are required to be managed according to applicable State and Federal regulations, and Department of Energy Orders that provide for the protection of human health and the environment. The Mixed and Low-Level Waste Treatment Facility Project was chartered in 1991, by the Department of Energy to provide treatment capability for these mixed and low-level waste streams. The first project task consisted of conducting engineering studies to identify the waste streams, their potential treatment strategies, and the requirements that would be imposed on the waste streams and the facilities used to process them. This report, Appendix A, Environmental Regulatory Planning Documentation, identifies the regulatory requirements that would be imposed on the operation or construction of a facility designed to process the INEL's waste streams. These requirements are contained in five reports that discuss the following topics: (1) an environmental compliance plan and schedule, (2) National Environmental Policy Act requirements, (3) preliminary siting requirements, (4) regulatory justification for the project, and (5) health and safety criteria.

  2. Modeling of pilot's visual behavior for low-level flight

    NASA Astrophysics Data System (ADS)

    Schulte, Axel; Onken, Reiner

    1995-06-01

    Developers of synthetic vision systems for low-level flight simulators deal with the problem to decide which features to incorporate in order to achieve most realistic training conditions. This paper supports an approach to this problem on the basis of modeling the pilot's visual behavior. This approach is founded upon the basic requirement that the pilot's mechanisms of visual perception should be identical in simulated and real low-level flight. Flight simulator experiments with pilots were conducted for knowledge acquisition. During the experiments video material of a real low-level flight mission containing different situations was displayed to the pilot who was acting under a realistic mission assignment in a laboratory environment. Pilot's eye movements could be measured during the replay. The visual mechanisms were divided into rule based strategies for visual navigation, based on the preflight planning process, as opposed to skill based processes. The paper results in a model of the pilot's planning strategy of a visual fixing routine as part of the navigation task. The model is a knowledge based system based upon the fuzzy evaluation of terrain features in order to determine the landmarks used by pilots. It can be shown that a computer implementation of the model selects those features, which were preferred by trained pilots, too.

  3. A comparison of simulation models for predicting soil water dynamics in bare and vegetated lysimeters

    SciTech Connect

    Link, S.O.; Kickert, R.N.; Fayer, M.J.; Gee, G.W.

    1993-06-01

    This report describes the results of simulation models used to predict soil water storage dynamics at the Field Lysimeter Test Facility (FLTF) weighing lysimeters. The objectives of this research is to develop the capability to predict soil water storage dynamics with plants in support of water infiltration control studies for the Hanford Permanent Isolation Barrier Development Program. It is important to gain confidence in one`s ability to simulate soil water dynamics over long time periods to assess the barrier`s ability to prevent drainage. Two models were compared for their ability to simulate soil water storage dynamics with and without plants in weighing lysimeters, the soil water infiltration and movement (SWIM) and the simulation of production and utilization of rangelands (SPUR-91) models. These models adequately simulated soil water storage dynamics for the weighing lysimeters. The range of root mean square error values for the two models was 7.0 to 19.8. This compares well with the range reported by Fayer et al. (1992) for the bare soil data sets of 8.1 to 22.1. Future research will test the predictive capability of these models for longer term lysimeter data sets and for historical data sets collected in various plant community types.

  4. Seventh annual DOE LLWMP participants' information meeting. DOE Low-Level Waste Management Program. Abstracts

    SciTech Connect

    Not Available

    1985-08-01

    The following sessions were held: International Low-Level Waste Management Activities; Low-Level Waste Disposal; Characteristics and Treatment of Low-Level Waste; Environmental Monitoring and Performance; Greater Confinement and Alternative Disposal Methods; Low-Level Waste Management; Corrective Measures; Performance Prediction and Assessment; and Siting New Defense and Commercial Low-Level Waste Disposal Facilities.

  5. A preliminary evaluation of alternatives for treatment of INEL Low-Level Waste and low-level mixed waste

    SciTech Connect

    Smith, T.H.; Roesener, W.S.; Jorgensen-Waters, M.J.; Edinborough, C.R.

    1992-06-01

    The Mixed and Low-Level Waste Treatment Facility (MLLWTF) project was established in 1991 by the US Department of Energy Idaho Field Office to provide treatment capabilities for Idaho National Engineering Laboratory (INEL) low-level mixed waste and low-level waste. This report identifies and evaluates the alternatives for treating that waste. Twelve treatment alternatives, ranging from ``no-action`` to constructing and operating the MLLWTF, are identified and evaluated. Evaluations include facility performance, environmental, safety, institutional, schedule, and rough order-of-magnitude cost comparisons. The performance of each alternative is evaluated against lists of ``musts`` and ``wants.`` Also included is a discussion of other key considerations for decision making. Analysis of results indicated further study is necessary to obtain the best estimate of future waste volumes and characteristics from the expanded INEL Decontamination and Decommissioning Program. It is also recommended that conceptual design begin as scheduled on the MLLWTF, maximum treatment alternative while re-evaluating the waste volume projections.

  6. Combining low level features and visual attributes for VHR remote sensing image classification

    NASA Astrophysics Data System (ADS)

    Zhao, Fumin; Sun, Hao; Liu, Shuai; Zhou, Shilin

    2015-12-01

    Semantic classification of very high resolution (VHR) remote sensing images is of great importance for land use or land cover investigation. A large number of approaches exploiting different kinds of low level feature have been proposed in the literature. Engineers are often frustrated by their conclusions and a systematic assessment of various low level features for VHR remote sensing image classification is needed. In this work, we firstly perform an extensive evaluation of eight features including HOG, dense SIFT, SSIM, GIST, Geo color, LBP, Texton and Tiny images for classification of three public available datasets. Secondly, we propose to transfer ground level scene attributes to remote sensing images. Thirdly, we combine both low-level features and mid-level visual attributes to further improve the classification performance. Experimental results demonstrate that i) Dene SIFT and HOG features are more robust than other features for VHR scene image description. ii) Visual attribute competes with a combination of low level features. iii) Multiple feature combination achieves the best performance under different settings.

  7. A rainfall loading response recorded at 300 meters depth: Implications for geological weighing lysimeters

    USGS Publications Warehouse

    Sophocleous, M.; Bardsley, E.; Healey, J.

    2006-01-01

    Static pore water pressures in confined aquifers vary in response to ground surface loading changes, including precipitation and evaporation. Under certain hydrogeological conditions such aquifers can function as giant natural weighing lysimeters, referenced here as 'geological weighing lysimeters'. The extent of the land area 'weighed' increases with aquifer depth and it is of interest to establish at what depth it is still possible to monitor surface water budgets. An 86 mm rainfall event produced a clear loading signal in a well in western Kansas at 300 m depth. The loading effect is quantitatively consistent with elastic deformation induced by the rainfall mass and suggests that geological weighing lysimeters could operate at considerably greater depths, thereby monitoring water budgets over a significant land area. ?? 2005 Elsevier Ltd All rights reserved.

  8. A calibration procedure for load cells to improve accuracy of mini-lysimeters in monitoring evapotranspiration

    NASA Astrophysics Data System (ADS)

    Misra, R. K.; Padhi, J.; Payero, J. O.

    2011-08-01

    SummaryWe used twelve load cells (20 kg capacity) in a mini-lysimeter system to measure evapotranspiration simultaneously from twelve plants growing in separate pots in a glasshouse. A data logger combined with a multiplexer was used to connect all load cells with the full-bridge excitation mode to acquire load-cell signal. Each load cell was calibrated using fixed load within the range of 0-0.8 times the full load capacity of load cells. Performance of all load cells was assessed on the basis of signal settling time, excitation compensation, hysteresis and temperature. Final calibration of load cells included statistical consideration of these effects to allow prediction of lysimeter weights and evapotranspiration over short-time intervals for improved accuracy and sustained performance. Analysis of the costs for the mini-lysimeter system indicates that evapotranspiration can be measured economically at a reasonable accuracy and sufficient resolution with robust method of load-cell calibration.

  9. Quantifying soil evaporation and transpiration at the scale of a remote sensing pixel by extrapolating mini-lysimeter results with the aid of remote sensed surface temperatures

    NASA Astrophysics Data System (ADS)

    Voortman, B.; Bartholomeus, R.; Witte, J. M.

    2012-12-01

    Lysimeters are often used to measure evapotranspiration (Et) by changes in mass of a volume of soil. Precision lysimeters generate data of Et at a high resolution in the order of 0.02 to 0.05 mm. This resolution is often reported as the accuracy of the lysimeter, which is in fact the accuracy of the weighing device. Improper installation or design of lysimeters is often not accounted for when assessing their accuracy. In general, measurement errors due to improper environmental conditions will decrease with increasing surface area and depth of the lysimeter. This is primarily because a larger part of the lysimeter is unaffected by its boundaries and because heterogeneities in soil hydraulic properties and micro-climate are more averaged out. However, the cost of large systems make them unattractive and scientists often choose for more economical solutions, optimizing between lysimeter dimensions and costs. One of the difficulties when designing a lysimeter is controlling the boundary condition at the base of the lysimeter. In case of a freely draining lysimeter (atmospheric pressure at the bottom), the lower portion of the lysimeter must saturate to generate a hydraulic gradient in downward direction, after which the lysimeter starts to drain. In groundwater independent sites this will lead to a higher soil moisture content in the lysimeter in comparison with the surrounding soil. One could overcome this problem by using suction plates and vacuum pumps to set a suction level at the base of the lysimeter equal to the surrounding soil., In dry soils, however, suction plates may dry out beyond the air entry value of the ceramic material, which neutralizes the suction pressure. Furthermore, a sophisticated drainage system will increase the maintenance and construction cost of the lysimeter. Moisture conditions in lysimeters are difficult to control and whenever this affects the available water for rooting plants this will lead to erroneous measurements of Et. We

  10. The role of lysimeters in the development of our understanding of processes in the vadose zone relevant to contamination of groundwater aquifers

    NASA Astrophysics Data System (ADS)

    Goss, Michael J.; Ehlers, Wilfried; Unc, Adrian

    further highlighted the importance of preferential flow. Lysimeters have permitted investigation of the mechanisms by which these chemical and biological materials, which can be hazardous to human health, reach our sources of drinking water. They have also provided the means of identifying soil management practices that could be used to reduce the movement contaminants in the leachate from agricultural fields.