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Modeling the wind-fields of accidental releases with an operational regional forecast model

Description: The Atmospheric Release Advisory Capability (ARAC) is an operational emergency preparedness and response organization supported primarily by the Departments of Energy and Defense. ARAC can provide real-time assessments of atmospheric releases of radioactive materials at any location in the world. ARAC uses robust three-dimensional atmospheric transport and dispersion models, extensive geophysical and dose-factor databases, meteorological data-acquisition systems, and an experienced staff. Although it was originally conceived and developed as an emergency response and assessment service for nuclear accidents, the ARAC system has been adapted to also simulate non-radiological hazardous releases. For example, in 1991 ARAC responded to three major events: the oil fires in Kuwait, the eruption of Mt. Pinatubo in the Philippines, and the herbicide spill into the upper Sacramento River in California. ARAC`s operational simulation system, includes two three-dimensional finite-difference models: a diagnostic wind-field scheme, and a Lagrangian particle-in-cell transport and dispersion scheme. The meteorological component of ARAC`s real-time response system employs models using real-time data from all available stations near the accident site to generate a wind-field for input to the transport and dispersion model. Here we report on simulation studies of past and potential release sites to show that even in the absence of local meteorological observational data, readily available gridded analysis and forecast data and a prognostic model, the Navy Operational Regional Atmospheric Prediction System, applied at an appropriate grid resolution can successfully simulate complex local flows.
Date: September 11, 1995
Creator: Albritton, J.R.; Lee, R.L. & Sugiyama, G.
Partner: UNT Libraries Government Documents Department

Concentrations of a water soluble, gas-phase mercury species in ambient air: Results from measurements and modeling

Description: There are few reliable data on the speciation of Hg in ambient air, although this information is critical to understanding the fate of Hg once released from point sources. The water soluble species of Hg that are thought to exist in flue gases would be subject to far greater local removal rates than is elemental Hg vapor, but methods are lacing to quantify this species. The authors developed a method using refluxing mist chambers to measure the airborne concentrations of reactive gaseous mercury (RGM) in short-term samples under ambient conditions. The method exhibits an effective detection limit of 0.02 ng/m{sup 3} and a precision for ambient concentration levels of {+-}20--30%. Using a model that simulates atmospheric transport and fate of anthropogenic mercury emissions over the contiguous United States, the authors generated 24-hr RGM concentrations to compare to the measurement data. The average RGM concentrations measured with their mist chambers at sites in Tennessee (TN) and Indiana (IN) were 0.065 ng/m{sup 3} and 0.100 ng/m{sup 3}, respectively. These averages represent about 3% of total gaseous mercury (TGM), and RGM generally exceeds regional particulate Hg. The 24-hr model-simulated RGM concentration averages in the modeling grid cells representing TN and IN are 0.051 ng/m{sup 3} and 0.098 ng/m{sup 3} respectively, in good agreement with the data. The measured concentrations at the two sites exhibit weak positive correlations with temperature, solar radiation, O{sub 3}, SO{sub 2}, and TGM. These concentrations are high enough to suggest that RGM can play an important role in both wet and dry deposition on a regional scale.
Date: December 31, 1997
Creator: Lindberg, S. E.; Stratton, W. J.; Pai, P. & Allan, M. A.
Partner: UNT Libraries Government Documents Department

Diagnostic modeling for real-time emergency response

Description: The Atmospheric Release Advisory Capability (ARAC) provides real-time dose assessments for airborne pollutant releases. ARAC is currently in the process of developing an entirely new suite of models and system infrastructure. Diagnostic and dispersion algorithms are being created in-house and a prognostic model NO-RAPS, imported from the Naval Research Laboratory, Monterey, is currently being adapted to ARAC`s needs. Diagnostic models are essential for an emergency response capability since they provide the ability to rapidly assimilate available meteorological data and generate the mass-consistent three-dimensional wind fields required by dispersion models. The resulting wind fields may also serve to initialize and validate prognostic models. In general, the performance of diagnostic models strongly correlates with the density and distribution of measurements in the area of interest and the resolution of the terrain. problem, data can be extracted from user-specified databases within a region defined by a metdata grid. Typically the data collection region will cover a geographic domain significantly larger than the area involved in the dispersion simulation in order to provide the most complete set of meteorological information relevant to the problem. This also permits the user to redefine the problem grid size and location, within limits, without reaccessing the meteorological data extraction system. After the data has been collected, an associated meteorological preprocessor places it in a standard form for further processing. The pre-processor does not alter or interpolate wind values; it only performs reversible transformations to convert the data to a standard unambiguous form, e.g. latitude, longitude, height, wind speed and direction. This allows the diagnostic models to use a generalized data ingest routine, not dependent on the form or format of the meteorological data source or database.
Date: September 7, 1995
Creator: Sugiyama, G.; Rodriguez, D. & Lee, R.
Partner: UNT Libraries Government Documents Department

A novel optical scattering collection system for particulate monitoring applications

Description: Light collecting systems often require radically different optical surfaces than those commonly found in optical imaging systems. An optical particulate monitor must probe a volume in emission stacks to obtain a good statistical distribution of suspended particles. However, ideal imaging systems map object planes into conjugate image planes and can probe only small volumes. The authors describe the design, fabrication and performance of a novel optical scattering collection system that exploits precision-engineered reflective conical surfaces (axicons) in a telescopic arrangement that maps a line in object space onto the detector plane in image space. Such non-spherical surfaces are nearly impossible to fabricate using traditional methods, but can readily be made using the deterministic method of single-point diamond turning. In addition to complex optical surfaces, single-point diamond turning also makes possible the precision engineering of reference surfaces useful for built-in alignment of multiple surfaces and rapid assembly of the finished system.
Date: May 1, 1996
Creator: Bernacki, B.E.; Miller, A.C. Jr. & Nuspliger, R.J.
Partner: UNT Libraries Government Documents Department

Integration of GIS technology with air compliance for the Oak Ridge National Laboratory

Description: ORNL uses a Geographical Information System (GIS) to achieve air quality compliance effectively and with minimum expense. Since implementation of MapInfo for Environmental Air Compliance activities, plant-wide adoption of the sytem is occurring. The common forum for data exchange allows compliance groups to pursue more of a management and planning rather than merely a regulatory role. Field surveys are implemented by personnel directly involved with the activities and this data is then transmitted via MapInfo. Examples are given of how the Environmental Compliance Section at ORNL uses it to achieve air quality compliance for Titles III and V, NEPA, and NESHAPs.
Date: December 31, 1994
Creator: Gurney, I.A. & Humphreys, M.P.
Partner: UNT Libraries Government Documents Department

The new ozone monitor. Final report

Description: This report describes the development of an invention for measuring the concentration of ozone by measuring the heat evolved when the ozone is catalyzed and converted back to oxygen. This ozone monitor evolved through a number of prototype as described in the final report. The final instrument is accurate, reliable and can be installed as a part of a control system. This instrument can be built and calibrated for any necessary specific ozone concentration range. This instrument uses inexpensive parts and would be simple to maintain. the manufacturing cost is less than any equally reliable and accurate ozone monitor presently available. The advantage this system has is that the ozone is directly measured as the temperature of the catalyst. It does not need UV lamps (which continually degrade in use and have a variable life) or use any chemistry where a material is continuously used up. This new ozone monitor directly measures the heat that is generated from the ozone as it converts back into oxygen as the gas mixture flows through the catalyst. The catalyst has theocratically an infinite life. It can clog if the system it is installed in, is dusty. But in systems that produce ozone, it is important that the gas is clean. Under normal clean gas conditions this instrument will give long term service free monitoring.
Date: September 20, 1994
Creator: Karlson, E.L.
Partner: UNT Libraries Government Documents Department

Development of an air emissions inventory for Oak Ridge National Laboratory

Description: Accurate air emissions inventory is important in an effective Clean Air Act (CAA) compliance program; without it, a facility may have difficulty proving compliance with regulations or permit conditions. An emissions inventory can also serve for evaluating the applicability of new regulations (eg, Title V of CAA) and in complying with them. Therefore it is important for the inventory to be well-planned and comprehensive. Preparation of an emissions inventory for a large R&D facility such as ORNL can be a challenging task. ORNL, a government facility managed by Lockheed Martin Energy Research Corp. for US DOE, consists of more than 300 buildings on about 1,500 acres. It has several thousand diverse emission sources, including small laboratory hoods, several wastewater treatment facilities, and a steam plant. This paper describes the development of ORNL`s emissions inventory with emphasis on setting goals and identifying the scope of the inventory, identifying the emission points, developing/implementing the inventory methodology, compiling data, and evaluating the results.
Date: August 1, 1996
Creator: Skipper, D.D.
Partner: UNT Libraries Government Documents Department

Hanford site near-facility environmental monitoring annual report, calendar year 1996

Description: This document summarizes the results of the near-facility environmental monitoring results for 1996 in the 100, 200/600, and 300/400 areas of the Hanford Site in south-central Washington State. Surveillance activities included sampling and analyses of ambient air, surface water, groundwater, soil, sediments, and biota. Also, external radiation measurements and radiological surveys were taken at waste disposal sites, radiologically controlled areas, and roads. These activities were conducted to assess and control the effects of nuclear facilities and waste sites on the local environment. The monitoring implements applicable portions of DOE Orders 5400.1 (DOE 1988a), 5400.5 (DOE 1990), and 5820.2A (DOE 1988b); Washington Administrative Code (WAC) 246-247; and Title 40 Code of Federal Regulations (CFR) Part 61, Subpart H (EPA 1989). In addition, diffuse sources were monitored to determine compliance with federal, state, and/or local regulations. In general, although effects from nuclear facilities can still be observed on the Hanford Site and radiation levels were slightly elevated when compared to offsite locations, the differences are less than in previous years.
Date: August 5, 1997
Creator: Perkins, C.J.
Partner: UNT Libraries Government Documents Department

Hanford environmental management program multi-year work plan FY1998

Description: The Environmental Support FY 1998 Multi-Year Work Plan (MYWP), consisting of the Hanford Environmental Management Program (HEMP) and the Effluent and Environmental Monitoring (EEM) Program MYWP is prepared to specifically establish the execution year`s work scope, budget targets, and schedule baselines. The work plan contains the work breakdown structure (WBS) and the WBS dictionary, milestone listings and milestone description sheets, and cost targets that the program manager will use to manage program work for the fiscal year. Where activities required to maintain or attain compliance with environmental requirements and agreements are impacted as a result of a reduction of the authorized funds, the ``Work Authorization`` identifies the impacted scope and requires the Contracting Officer`s or Assistant Manager-Contracting Officer`s Representative signature. Change requests will be submitted to RL by the contractor for approval, further documenting the impacts of any environmental and agreement noncompliances as a result of funding limitations. This is the first year that the MYWPs are submitted under the new Project Hanford Management Contractor (PHMC). The MYWPs are structured differently than in prior years. The MYWP is divided into two main sections. Section One is titled the ``Project Summary Section`` and Section Two is titled the ``Additional Sections at the Project Baseline Summaries Level``. Section One is where the major project summary-level information is provided. Section Two is designed to detail the information for each Project Baseline Summary (PBS) that falls under the purview of the major project listed in Section One. Considering all of the PHMC MYWPs, the HEMP and EEM programs are the one exception to the above description. HEMP and EEM are two of five separate programs that are organized under one common PBS that is titled Mission Support (PBS {number_sign} RL-OT01). RL has given guidance that HEMP and EEM will be submitted as one common ...
Date: August 25, 1997
Creator: Giese, K.A.
Partner: UNT Libraries Government Documents Department

US Department of Energy report 1996 LANL radionuclide air emissions

Description: Presented is the Laboratory-wide certified report regarding radioactive effluents released into the air by the Los Alamos National Laboratory (LANL) in 1996. This information is required under the Clean Air Act and is being reported to the U.S. Environmental Protection Agency (EPA). The effective dose equivalent (EDE) to a hypothetical maximum exposed individual (MEI) of the public was calculated, using procedures specified by the EPA and described in this report. That dose was 1.93 mrem for 1996. Emissions of {sup 11}C, {sup 13}N, and {sup 15}O from a 1-mA, 800 MeV proton accelerator contributed over 92% of the EDE to LANL`s MEI. Using CAP88, the EPA`s dose assessment model, more than 86% of the total dose received by the MEI was via the air immersion pathway.
Date: August 1, 1997
Creator: Jacobson, K.W.
Partner: UNT Libraries Government Documents Department

LLNL NESHAPs 1996 Annual Report

Description: This annual report is prepared pursuant to the National Emissions Standards for Hazardous Air Pollutants (NESHAPs) 40 CFR Part 61, Subpart H; Subpart H governs radionuclide emissions to air from Department of Energy (DOE) facilities. NESHAPs limits the emission of radionuclides to the ambient air from DOE facilities to levels resulting in an annual effective dose equivalent (EDE) of 10 mrem (10 microsieverts) to any member of the public. The EDEs for the Lawrence Livermore National Laboratory (LLNL) site-wide maximally exposed members of the public from 1996 operations were (1) Livermore site: 0. 093 mrem (0.93 microsievert) (52% from point-source emissions, 48% from diffuse-source emissions); (2) Site 300: 0.033 mrem (0.33 microsievert) (99% from point-source, 1% from diffuse-source emissions). The EDEs were generally calculated using the EPA-approved CAP88-PC air-dispersion/dose-assessment model. Site-specific meteorological data, stack flow data, and emissions estimates based on radionuclide inventory data or continuous-monitoring systems data were the specific input to CAP88-PC for each modeled source. 5 figs., 8 tabs.
Date: January 6, 1997
Creator: Gallegos, G.M.
Partner: UNT Libraries Government Documents Department

Monitoring airborne alpha-emitter contamination

Description: Facilities that may produce airborne alpha emitter contamination require a continuous air monitoring (CAM) system. However, these traditional CAMs have difficulty in environments with large quantities of non-radioactive particulates such as dust and salt. Los Alamos has developed an airborne plutonium sensor (APS) for the REBOUND experiment at the Nevada Test Site which detects alpha contamination directly in the air, and so is less vulnerable to the problems associated with counting activity on a filter. In addition, radon compensation is built into the detector by the use of two measurement chambers.
Date: February 1, 1998
Creator: Kerr, P.L.; Koster, J.E.; Conaway, J.G.; Bounds, J.A.; Whitley, C.W. & Steadman, P.A.
Partner: UNT Libraries Government Documents Department

Application of resonance Raman LIDAR for chemical species identification

Description: BNL has been developing a remote sensing technique for the detection of atmospheric pollutants based on the phenomenon of resonance Raman LIDAR that has also incorporated a number of new techniques/technologies designed to extend it`s performance envelope. When the excitation frequency approaches an allowed electronic transition of the molecule, an enormous enhancement of the inelastic scattering cross-section can occur, often up to 2 to 4 orders-of-magnitude, and is referred to as resonance Raman (RR), since the excitation frequency is in resonance with an allowed electronic transition. Exploitation of this enhancement along with new techniques such as pattern recognition algorithms to take advantage of the spectral fingerprint and a new laser frequency modulation technique designed to suppress broadband fluorescence, referred to as Frequency modulated Excitation Raman Spectroscopy (FreMERS) and recent developments in liquid edge filter technology, for suppression of the elastic channel, all help increase the overall performance of Raman LIDAR.
Date: July 1, 1997
Creator: Chen, C.L.; Heglund, D.L.; Ray, M.D.; Harder, D.; Dobert, R.; Leung, K.P. et al.
Partner: UNT Libraries Government Documents Department

Trace gas measurements in Phoenix, Arizona (1998)

Description: The DOE Atmospheric Chemistry Program, and the Arizona Department of Environmentel Quality (DEQ) conducted a field program in the Phoenix Metropolitan area in the late spring of 1998. The experiment was composed of a linked set of aircraft and surface measurements designed to characterize the chemical and meteorological processes leading to ozone episodes. The existing network of Arizona DEQ sites in Phoenix was utilized to document ground level concentrations of ozone and its precursors. West of the downtown area, a site (Usery Pass) was set up for the detailed characterization of the mature Phoenix urban plume. Detailed measurements in the source region were made at several sites in downtown Phoenix. The DOE G-1 aircraft, equipped wih a comprehensive array of instruments to characterize atmospheric trace gas and aerosol composition, flew over the region at various times during the day. All times in the following discussion are local standard time (LST). Morning flights were typically made between 08:00 and 12:00 upwind, to measure background concentrations, and over the Phoenix source region, to characterize the sources of ozone precursors. Afternoon flights over the Phoenix source region and downwind between 15:00 and 18:00 were made to examine the chemical properties and physical distribution of the photochemically aged urban plume. The aircraft flights typically included an atmospheric sounding to circa 3 km upwind and over Phoenix in the morning, and downwind in the afternoon. A total of 22 flights were made on 14 different days during the one month program. The motivation for conducting the program was to examine ozone formation rates and efficiencies in an environment where the pollutant mix is dominated by vehicle emissions, where the contribution of biogenic hydocarbons to ozone formation is thought to be low, and where processing conditions are different than they are in the Eastern US. The ...
Date: January 9, 2000
Creator: Nunnermacker, L.J.
Partner: UNT Libraries Government Documents Department

SAGE II/Umkehr ozone comparisons and aerosols effects: An empirical and theoretical study. Final report

Description: The objectives of this research were to: (1) examine empirically the aerosol effect on Umkehr ozone profiles using SAGE II aerosol and ozone data; (2) examine theoretically the aerosol effect on Umkehr ozone profiles; (3) examine the differences between SAGE II ozone profiles and both old- and new-format Umkehr ozone profiles for ozone-trend information; (4) reexamine SAGE I-Umkehr ozone differences with the most recent version of SAGE I data; and (5) contribute to the SAGE II science team.
Date: September 15, 1997
Creator: Newchurch, M.
Partner: UNT Libraries Government Documents Department

A continuous sampling air-ICP for metals emission monitoring

Description: An air-inductively coupled plasma (air-ICP) system has been developed for continuous sampling and monitoring of metals as a continuous emission monitor (CEM). The plasma is contained in a metal enclosure to allow reduced-pressure operation. The enclosure and plasma are operated at a pressure slightly less than atmospheric using a Roots blower, so that sample gas is continuously drawn into the plasma. A Teflon sampling chamber, equipped with a sampling pump, is connected to the stack that is to be monitored to isokinetically sample gas from the exhaust line and introduce the sample into the air-ICP. Optical emission from metals in the sampled gas stream is detected and monitored using an acousto-optic tunable filter (AOTF)--echelle spectrometer system. A description of the continuous sampling air-ICP system is given, along with some preliminary laboratory data for continuous monitoring of metals.
Date: September 19, 1999
Creator: Baldwin, D.P.; Zamzow, D.S.; Eckels, D.E. & Miller, G.P.
Partner: UNT Libraries Government Documents Department

Status report and FY95 plans -- Re-evaluation of NOAA Dobson spectrophotometer total ozone data. 1994 annual report

Description: The goal of this project was to re-evaluate NOAA/CMDL Dobson spectrophotometer total ozone data during FY94 from the stations Haute Provence, France; Lauder, New Zealand; Perth, Australia; and Poker Flat, Alaska and the Umkehr data from Boulder, Colorado and Mauna Loa, Hawaii. During the second year the authors planned to re-evaluate total ozone data from Byrd, Hallett and South Pole, Antarctica; Fairbanks, Alaska; Puerto Montt, Chile; Huancayo, Peru and Umkehr data from Huancayo.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

296-B-13 stack monitoring and sampling system: Annual system assessment report

Description: This report presents the details of the annual system assessment of the air pollution monitoring and sampling system for the 296-13 stack at the Hanford site. Topics discussed include; system description, system status, system aging, spare parts considerations, long term maintenance plan, trends, and items requiring action.
Date: May 16, 1995
Creator: Ridge, T.M.
Partner: UNT Libraries Government Documents Department

Evaluation of ELISA screening test for detecting aflatoxin in biogenic dust samples

Description: Aflatoxin is a carcinogenic chemical that is sometimes produced when agricultural commodities are infested by the fungi Aspergillus flavus and A. Parasiticus. Aflatoxin has been found to be present in air samples taken around persons handling materials likely to be contaminated. The purpose of this investigation was to demonstrate the feasibility of using an Enzyme Linked Immunosorbent Assay (ELISA) test kit that was developed to screen for aflatoxin in bulk agricultural commodities, to an air sample. Samples were taken from two environments likely to be contaminated with aflatoxin, a dairy farm feed mixing operation and a peanut bagging operation. The dust collected from these environments was considered to be biogenic, in that it originated primarily from biological materials.
Date: May 1, 1996
Creator: Durant, J.T.
Partner: UNT Libraries Government Documents Department

Using Absolute Humidity and Radiochemical Analyses of Water Vapor Samples to Correct Underestimated Atmospheric Tritium Concentrations

Description: Los Alamos National Laboratory (LANL) emits a wide variety of radioactive air contaminants. An extensive ambient air monitoring network, known as AIRNET, is operated on-site and in surrounding communities to estimate radioactive doses to the public. As part of this monitoring network, water vapor is sampled continuously at more than 50 sites. These water vapor samples are collected every two weeks by absorbing the water vapor in the sampled air with silica gel and then radiochemically analyzing the water for tritium. The data have consistently indicated that LANL emissions cause a small, but measurable impact on local concentrations of tritium. In early 1998, while trying to independently verify the presumed 100% water vapor collection efficiency, the author found that this efficiency was normally lower and reached a minimum of 10 to 20% in the middle of summer. This inefficient collection was discovered by comparing absolute humidity (g/m{sup 3}) calculated from relative humidity and temperature to the amount of water vapor collected by the silica gel per cubic meter of air sampled. Subsequent experiments confirmed that the elevated temperature inside the louvered housing was high enough to reduce the capacity of the silica gel by more than half. In addition, their experiments also demonstrated that, even under optimal conditions, there is not enough silica gel present in the sampling canister to absorb all of the moisture during the higher humidity periods. However, there is a solution to this problem. Ambient tritium concentrations have been recalculated by using the absolute humidity values and the tritium analyses. These recalculated tritium concentrations were two to three times higher than previously reported. Future tritium concentrations will also be determined in the same manner. Finally, the water vapor collection process will be changed by relocating the sampling canister outside the housing to increase collection efficiency and, ...
Date: June 1, 1999
Creator: Eberhart, C.F.
Partner: UNT Libraries Government Documents Department

Carbon-13 isotopic abundance and concentration of atmospheric methane for background air in the Southern and Northern Hemispheres from 1978 to 1989

Description: Atmospheric methane (CH{sub 4}) may become an increasingly important contributor to global warming in future years. Its atmospheric concentration has risen, doubling over the past several hundred years, and additional methane is thought to have a much greater effect on climate, on a per molecule basis, than additional C0{sub 2} at present day concentrations (Shine et al. 1990). The causes of the increase of atmospheric CH{sub 4} have been difficult to ascertain because of a lack of quantitative knowledge of the fluxes (i.e., net emissions) from the numerous anthropogenic and natural sources. The goal of CH{sub 4} isotopic studies is to provide a constraint (and so reduce the uncertainties) in estimating the relative fluxes from the various isotopically distinct sources, whose combined fluxes must result in the measured atmospheric isotopic composition, after the fractionating effect of the atmospheric removal process is considered. In addition, knowledge of the spatial and temporal changes in the isotopic composition of atmospheric CH{sub 4}, along with estimates of the fluxes from some of the major sources, makes it possible to calculate growth rates for sources whose temporal emissions trends would be difficult to measure directly.
Date: March 1995
Creator: Stevens, C. M.; Sepanski & Morris, L. J.
Partner: UNT Libraries Government Documents Department