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Combustion Byproducts Recycling Consortium

Description: Each year, over 100 million tons of solid byproducts are produced by coal-burning electric utilities in the United States. Annual production of flue gas desulfurization (FGD) byproducts continues to increase as the result of more stringent sulfur emission restrictions. In addition, stricter limits on NOx emissions mandated by the 1990 Clean Air Act have resulted in utility burner/boiler modifications that frequently yield higher carbon concentrations in fly ash, which restricts the use of the ash as a cement replacement. Controlling ammonia in ash is also of concern. If newer, “clean coal” combustion and gasification technologies are adopted, their byproducts may also present a management challenge. The objective of the Combustion Byproducts Recycling Consortium (CBRC) is to develop and demonstrate technologies to address issues related to the recycling of byproducts associated with coal combustion processes. A goal of CBRC is that these technologies, by the year 2010, will lead to an overall ash utilization rate from the current 34% to 50% by such measures as increasing the current rate of FGD byproduct use and increasing in the number of uses considered “allowable” under state regulations. Another issue of interest to the CBRC would be to examine the environmental impact of both byproduct utilization and disposal. No byproduct utilization technology is likely to be adopted by industry unless it is more cost-effective than landfilling. Therefore, it is extremely important that the utility industry provide guidance to the R&D program. Government agencies and privatesector organizations that may be able to utilize these materials in the conduct of their missions should also provide input. The CBRC will serve as an effective vehicle for acquiring and maintaining guidance from these diverse organizations so that the proper balance in the R&D program is achieved.
Date: August 31, 2008
Creator: Ziemkiewicz, Paul; Vandivort, Tamara; Pflughoeft-Hassett, Debra; Chugh, Y Paul & Hower, James
Partner: UNT Libraries Government Documents Department

An aerial radiological survey of the Nevada Test Site

Description: A team from the Remote Sensing Laboratory conducted an aerial radiological survey of the US Department of Energy's Nevada Test Site including three neighboring areas during August and September 1994. The survey team measured the terrestrial gamma radiation at the Nevada Test Site to determine the levels of natural and man-made radiation. This survey included the areas covered by previous surveys conducted from 1962 through 1993. The results of the aerial survey showed a terrestrial background exposure rate that varied from less than 6 microroentgens per hour (mR/h) to 50 mR/h plus a cosmic-ray contribution that varied from 4.5 mR/h at an elevation of 900 meters (3,000 feet) to 8.5 mR/h at 2,400 meters (8,000 feet). In addition to the principal gamma-emitting, naturally occurring isotopes (potassium-40, thallium-208, bismuth-214, and actinium-228), the man-made radioactive isotopes found in this survey were cobalt-60, cesium-137, europium-152, protactinium-234m an indicator of depleted uranium, and americium-241, which are due to human actions in the survey area. Individual, site-wide plots of gross terrestrial exposure rate, man-made exposure rate, and americium-241 activity (approximating the distribution of all transuranic material) are presented. In addition, expanded plots of individual areas exhibiting these man-made contaminations are given. A comparison is made between the data from this survey and previous aerial radiological surveys of the Nevada Test Site. Some previous ground-based measurements are discussed and related to the aerial data. In regions away from man-made activity, the exposure rates inferred from the gamma-ray measurements collected during this survey agreed very well with the exposure rates inferred from previous aerial surveys.
Date: December 1, 1999
Creator: Hendricks, T J & Riedhauser, S R
Partner: UNT Libraries Government Documents Department

Appalachian Rivers II Conference: Technology for Monitoring, Assessing, and Restoring Streams, Rivers, and Watersheds

Description: On July 28-29, 1999, the Federal Energy Technology Center (FETC) and the WMAC Foundation co-sponsored the Appalachian Rivers II Conference in Morgantown, West Virginia. This meeting brought together over 100 manufacturers, researchers, academicians, government agency representatives, watershed stewards, and administrators to examine technologies related to watershed assessment, monitoring, and restoration. Sessions included presentations and panel discussions concerning watershed analysis and modeling, decision-making considerations, and emerging technologies. The final session examined remediation and mitigation technologies to expedite the preservation of watershed ecosystems.
Date: July 29, 1999
Partner: UNT Libraries Government Documents Department

Hanford Site Groundwater Monitoring for Fiscal Year 2000

Description: This report presents the results of groundwater and vadose zone monitoring and remediation for fiscal year 2000 on the U.S. Department of Energy's Hanford Site, Washington. The most extensive contaminant plumes are tritium, iodine-129, and nitrate, which all had multiple sources and are very mobile in groundwater. Carbon tetrachloride and associated organic constituents form a relatively large plume beneath the central part of the Site. Hexavalent chromium is present in smaller plumes beneath the reactor areas along the river and beneath the central part of the site. Strontium-90 exceeds standards beneath each of the reactor areas, and technetium-99 and uranium are present in the 200 Areas. RCRA groundwater monitoring continued during fiscal year 2000. Vadose zone monitoring, characterization, remediation, and several technical demonstrations were conducted in fiscal year 2000. Soil gas monitoring at the 618-11 burial ground provided a preliminary indication of the location of tritium in the vadose zone and in groundwater. Groundwater modeling efforts focused on 1) identifying and characterizing major uncertainties in the current conceptual model and 2) performing a transient inverse calibration of the existing site-wide model. Specific model applications were conducted in support of the Hanford Site carbon tetrachloride Innovative Treatment Remediation Technology; to support the performance assessment of the Immobilized Low-Activity Waste Disposal Facility; and in development of the System Assessment Capability, which is intended to predict cumulative site-wide effects from all significant Hanford Site contaminants.
Date: March 1, 2001
Creator: Hartman, Mary J.; Morasch, Launa F. & Webber, William D.
Partner: UNT Libraries Government Documents Department

Use of Multi-Level Wells in Developing a 3-Dimensional Understanding of Groundwater Flow and Contaminant Migration at the Savannah River Site

Description: Understanding the flow of groundwater and contaminants in 3-dimensions, along with hydraulic properties, is instrumental in selection and implementation of successful remediation efforts. Advances in multi-level groundwater monitoring at the Savannah River Site (SRS) are enabling engineers and geologists to collect the needed characterization data in an efficient, cost-effective manner. The SRS has developed a new multi-level groundwater monitoring well, �StrataSampler�, which is being deployed for characterization and monitoring at several large groundwater plumes on the SRS. The installation method used allowed collection of data during the drilling process allowing optimization of screen placement within the aquifers and minimization of drilling costs and waste generation. Data generated during the installation of the StrataSamplers along with data collected from the installed wells is being used to understand the 3-dimensional nature of contaminant fate and transport. The L-Area Southern Groundwater Operable Unit is the first full-scale deployment of StrataSampler wells at SRS. Twenty-two StrataSampler wells with a total of 52 sampling zones were installed. The installation, development, hydraulic testing, sampling of the StrataSamplers at this unit and the resulting understanding of the contaminant plumes will be discussed in the paper and presentation.
Date: February 25, 2003
Creator: Vangelas, K. M.; Nichols, R. L.; Flach, G. P.; Sappington, F.; Simmons, J. L.; Betivas, C. R. et al.
Partner: UNT Libraries Government Documents Department

PROGRESSIVE VENTILATION OF THE OCEANS - POTENTIAL FOR RETURN TO ANOXIC CONDITIONS IN THE POST-PALEOZOIC

Description: After the ventilation of the residual anoxic layer in the late Paleozoic (Berry and Wilde, 1978) a return to ephemeral anoxic conditions in the ocean is suggested by anoxic sediments found in the Mesozoic cores of the deep-sea drilling program (Schlanger and Jenkyns 1977, and Theide and Van Andel 1977). A preliminary physical oceanographic model is presented to explain the development of oxygen depleted layers in mid-waters below the surface wind-mixed layer during non-glacial climates. The model shows the range of temperature, salinity and density values for hypothetical water masses for two climatically related oceanographic situations: Case A where bottom waters are formed at mid-latitudes at the surface salinity maxima, and Case B where bottom waters are produced at high latitudes but not by sea-ice formation as in the modern ocean. The hypothetical water masses are characterized by examples from the modern ocean and extrapolation to non-glacial times is made by eliminating water masses produced by or influenced by sea-ice formation in modern glacial times. The state of oxidation is made by plotting the model water masses on an oxygen saturation diagram and comparing the relative oxygen capacity with modern conditions of zonal organic productivity. The model indicates for Case A (high latitude temperatures above 5°C) two oxygen, depleted layers in the equatorial regions (1) from about 200m to the depth of completed oxidation of surface material separated by an oxygenated zone to (2) a deep depleted zone along the base of the pycnocline at 2900 M. The deep depleted zone extends along the Case A pycnocline polarward toward the high latitude productivity maximum. For case B with a pycnocline at about 1500m the deep anoxic layer is not sustained. Considerations of density only, suggest that neutral stratification and the potential for overturn is enhanced for climates transitional between Case …
Date: September 1, 1980
Creator: Wilde, Pat & Berry, William B.N.
Partner: UNT Libraries Government Documents Department

NNSS Soils Monitoring: Plutonium Valley (CAU366) FY2012

Description: The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Nevada Site Office (NSO), Environmental Restoration Soils Activity has authorized the Desert Research Institute (DRI) to conduct field assessments of potential sediment transport of contaminated soil from Corrective Action Unit (CAU) 366, Area 11 Plutonium Valley Dispersion Sites Contamination Area (CA) during precipitation runoff events. Field measurements at the T-4 Atmospheric Test Site (CAU 370) suggest that radionuclide-contaminated soils may have migrated along a shallow ephemeral drainage that traverses the site (NNSA/NSO, 2009). (It is not entirely clear how contaminated soils got into their present location at the T-4 Site, but flow to the channel has been redirected and the contamination does not appear to be migrating at present.) Aerial surveys in selected portions of the Nevada National Security Site (NNSS) also suggest that radionuclide-contaminated soils may be migrating along ephemeral channels in Areas 3, 8, 11, 18, and 25 (Colton, 1999). In Area 11, several low-level airborne surveys of the Plutonium Valley Dispersion Sites (CAU 366) show plumes of Americium 241 (Am-241) extending along ephemeral channels (Figure 1, marker numbers 5 and 6) below Corrective Action Site (CAS) 11-23-03 (marker number 3) and CAS 11 23-04 (marker number 4) (Colton, 1999). Plutonium Valley in Area 11 of the NNSS was selected for the study because of the aerial survey evidence suggesting downstream transport of radionuclide-contaminated soil. The aerial survey (Figure 1) shows a well defined finger of elevated radioactivity (marker number 5) extending to the southwest from the southernmost detonation site (marker number 4). This finger of contamination overlies a drainage channel mapped on the topographic base map used for presentation of the survey data suggesting surface runoff as a likely cause of the contaminated area. Additionally, instrumenting sites strongly suspected of conveying soil from areas of surface …
Date: January 1, 2013
Creator: Julianne J Miller, Steve A. Mizell, George Nikolich, Greg McCurdy, and Scott Campbell
Partner: UNT Libraries Government Documents Department

Innovative Water Management Technology to Reduce Environmental Impacts of Produced Water

Description: Clemson University with Chevron as an industry partner developed and applied treatment technology using constructed wetland systems to decrease targeted constituents in simulated and actual produced waters to achieve reuse criteria and discharge limits. Pilot-scale and demonstration constructed wetland treatment system (CWTS) experiments led to design strategies for treating a variety of constituents of concern (COCs) in produced waters including divalent metals, metalloids, oil and grease, and ammonia. Targeted biogeochemical pathways for treatment of COCs in pilot-scale CWTS experiments included divalent metal sulfide precipitation through dissimilatory sulfate reduction, metal precipitation through oxidation, reduction of selenite to insoluble elemental selenium, aerobic biodegradation of oil, nitrification of ammonia to nitrate, denitrification of nitrate to nitrogen gas, separation of oil using an oilwater separator, and sorption of ammonia to zeolite. Treatment performance results indicated that CWTSs can be designed and built to promote specific environmental and geochemical conditions in order for targeted biogeochemical pathways to operate. The demonstration system successfully achieved consistent removal extents even while inflow concentrations of COCs in the produced water differed by orders of magnitude. Design strategies used in the pilot-scale and demonstration CWTSs to promote specific conditions that can be applied to designing full-scale CWTSs include plant and soil selection, water-depth selection, addition of amendments, and hydraulic retention time (HRT). These strategies allow conditions within a CWTS to be modified to achieve ranges necessary for the preferred biogeochemical treatment pathways. In the case of renovating a produced water containing COCs that require different biogeochemical pathways for treatment, a CWTS can be designed with sequential cells that promote different conditions. For example, the pilot-scale CWTS for post-reverse osmosis produced water was designed to promote oxidizing conditions within the first wetland cell for nitrification of ammonia, and the subsequent three cells were designed to promote reducing conditions for denitrification of …
Date: May 15, 2013
Creator: Castle, James; Rodgers, John; Alley, Bethany; Beebe, Alex; Coffey, Ruthanne; Jurinko, Kristen et al.
Partner: UNT Libraries Government Documents Department

ON CALCULATING THE TRANSFER OF CARBON-13 IN RESERVOIR MODELS OF THE CARBON CYCLE

Description: An approach to calculating the transfer of isotopic tracers in reservoir models is outlined that takes into account the effects of isotopic fractionation at phase boundaries without any significant approximations. Simultaneous variations in both the rare isotopic tracer and the total elemental (the sum of its isotopes) concentration are considered. The proposed procedure is applicable to most models of the carbon cycle and a four-box model example is discussed. Although the exact differential equations are non-linear, a simple linear approximation exists that gives insight into the nature of the solution. The treatment will be in terms of isotopic ratios which are the directly measured quantities.
Date: February 1, 1980
Creator: Tans, Pieter P.
Partner: UNT Libraries Government Documents Department

The beryllium quandary: will the lower exposure limits spur new developments in sampling and analysis?

Description: At the time this article was written, new rulemakings were under consideration at OSHA and the U.S. Department of Energy (DOE) that would propose changes to occupational exposure limits for beryllium. Given these developments, it’s a good time to review the tools and methods available to IHs for assessing beryllium air and surface contamination in the workplace—what’s new and different, and what’s tried and true. The article discusses limit values and action levels for beryllium, problematic aspects of beryllium air sampling, sample preparation, sample analysis, and data evaluation.
Date: June 3, 2013
Creator: Brisson, Michael
Partner: UNT Libraries Government Documents Department

Final Report-Confirmatory Survey Results for the ABB Combustion Engineering Site, Windsor, Connecticut; Revision 1 (DCN 5158-SR-02-1) (Docket No. 030-03754; RFTA No. 12-003)

Description: The objectives of the confirmatory activities were to provide independent contractor field data reviews and to generate independent radiological data for use by the NRC in evaluating the adequacy and accuracy of the contractor�s procedures and FSS results. ORAU reviewed ABB CE�s decommissioning plan, final status survey plan, and the applicable soil DCGLs, which were developed based on an NRC-approved radiation dose assessment. The surveys included gamma surface scans, gamma direct measurements, and soil sampling.
Date: January 28, 2013
Creator: ADAMS, WADE C
Partner: UNT Libraries Government Documents Department
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