Download or read book Mobilization of Plutonium IV from Savannah River Site Sediments written by Leo Gumapas and published by . This book was released on 2005 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plutonium Oxication State Transformations and Their Consequence on Plutonium Transport Through Sediment During an 11 year Field Study written by DANIEL. KAPLAN and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Savannah River Site (SRS) contains a large inventory of plutonium (Pu), some of it in the form of Low-Level Waste (LLW). Much of this LLW has been or will be disposed at the E Area LLW Facility. As part of the permitting of LLW on-site disposal, SRS is required to periodically update the Performance Assessment calculations used in part to establish the facility specific amount of waste that can be safely disposed (or establish the Waste Acceptance Criteria). The objective of this project was to determine if a recent discovered change in plutonium chemistry (i.e., oxidation of PuO2, a common form of Pu waste, may form plutonium in the more mobile hexavalent form) was within the assumptions, parameters, and bases of the approved Performance Assessment WSRC (2000) and Composite Assessment, WSRC (1997). This project was initiated in 2001, and this is the final report describing laboratory and lysimeter (field) studies. Results from this year's work provided additional technical support f or the conceptual Pu geochemical model proposed for future risk-based calculations. When lysimeters containing Pu(III) or Pu(IV) were left exposed to the natural environment for 11 years, essentially all of the sediment-bound Pu existed as Pu(IV) and possibly Pu(III), the least mobile forms of Pu. This result was confirmed by two independent measurements, a very sensitive, indirect wet-chemistry method and a less-sensitive, direct spectroscopic technique, micro-X-ray adsorption near-edge structure (micro-XANES) spectroscopy. In these lysimeters, Pu sediment concentrations decreased on average an order-of-magnitude per centimeter for the first 5 cm below the source, an astounding rate of contaminant retardation. When Pu(VI), the more mobile form, may form from PuO2, was added to the lysimeters, the Pu moved faster than it had in the other lysimeters: Pu moving on average 12.5 cm/yr in the Pu(VI) lysimeter, compared to 0.9 cm/yr in the Pu(III) and Pu(IV) lysimeters. Importantly, transport modeling of the data clearly suggested that reduction of the original Pu(VI) occurred, thus most of the transport of the Pu in the lysimeter must have progressed during the early portion of the study, prior to the sediment-induced reduction of Pu(VI). When Pu(V) was added to the lysimeter sediment in a laboratory study, the Pu(V) quickly reduced to Pu(IV) within a couple days. These data together with those from previous reports for this project conclusively show that Pu, irrespective of the form it is introduced into SRS sediments, tends to convert rapidly to the plus 4, and possible plus 3, oxidation state, the least mobile form of Pu.

Download or read book F Canyon Plutonium Solutions Savannah River Site Aiken County Barnwell County written by and published by . This book was released on 1994 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book FORM AND AGING OF PLUTONIUM IN SAVANNAH RIVER SITE WASTE TANK 18 written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides a summary of the effects of aging on and the expected forms of plutonium in Tank 18 waste residues. The findings are based on available information on the operational history of Tank 18, reported analytical results for samples taken from Tank 18, and the available scientific literature for plutonium under alkaline conditions. These findings should apply in general to residues in other waste tanks. However, the operational history of other waste tanks should be evaluated for specific conditions and unique operations (e.g., acid cleaning with oxalic acid) that could alter the form of plutonium in heel residues. Based on the operational history of other tanks, characterization of samples from the heel residues in those tanks would be appropriate to confirm the form of plutonium. During the operational period and continuing with the residual heel removal periods, Pu(IV) is the dominant oxidation state of the plutonium. Small fractions of Pu(V) and Pu(VI) could be present as the result of the presence of water and the result of reactions with oxygen in air and products from the radiolysis of water. However, the presence of Pu(V) would be transitory as it is not stable at the dilute alkaline conditions that currently exists in Tank 18. Most of the plutonium that enters Savannah River Site (SRS) high-level waste (HLW) tanks is freshly precipitated as amorphous plutonium hydroxide, Pu(OH){sub 4(am)} or hydrous plutonium oxide, PuO{sub 2(am, hyd)} and coprecipitated within a mixture of hydrous metal oxide phases containing metals such as iron, aluminum, manganese and uranium. The coprecipitated plutonium would include Pu{sup 4+} that has been substituted for other metal ions in crystal lattice sites, Pu{sup 4+} occluded within hydrous metal oxide particles and Pu{sup 4+} adsorbed onto the surface of hydrous metal oxide particles. The adsorbed plutonium could include both inner sphere coordination and outer sphere coordination of the plutonium. PuO{sub 2(am, hyd)} is also likely to be present in deposits and scales that have formed on the steel surfaces of the tank. Over the operational period and after closure of Tank 18, Ostwald ripening has and will continue to transform PuO{sub 2(am, hyd)} to a more crystalline form of plutonium dioxide, PuO{sub 2(c)}. After bulk waste removal and heel retrieval operations, the free hydroxide concentration decreased and the carbonate concentration in the free liquid and solids increased. Consequently, a portion of the PuO{sub 2(am, hyd)} has likely been converted to a hydroxy-carbonate complex such as Pu(OH)2(CO3){sub (s)}. or PuO(CO3) · xH2O{sub (am)}. Like PuO{sub 2(am, hyd)}, Ostwald ripening of Pu(OH)2(CO3){sub (s)} or PuO(CO3) · xH2O{sub (am)} would be expected to occur to produce a more crystalline form of the plutonium carbonate complex. Due to the high alkalinity and low carbonate concentration in the grout formulation, it is expected that upon interaction with the grout, the plutonium carbonate complexes will transform back into plutonium hydroxide. Although crystalline plutonium dioxide is the more stable thermodynamic state of Pu(IV), the low temperature and high water content of the waste during the operating and heel removal periods in Tank 18 have limited the transformation of the plutonium into crystalline plutonium dioxide. During the tank closure period of thousands of years, transformation of the plutonium into a more crystalline plutonium dioxide form would be expected. However, the continuing presence of water, reaction with water radiolysis products, and low temperatures will limit the transformation, and will likely maintain an amorphous Pu(OH)4 or PuO{sub 2(am, hyd)} form on the surface of any crystalline plutonium dioxide produced after tank closure. X-ray Absorption Spectroscopic (XAS) measurements of Tank 18 residues are recommended to confirm coordination environments of the plutonium. If the presence of PuO(CO3){sub (am, hyd)} is confirmed by XAS, it is recommended that experiments be conducted to determine if plutonium carbonates are transformed back into PuO{sub 2(am, hyd)} upon contact with grout.

Download or read book Fluid Dynamics in Complex Fractured Porous Systems written by Boris Faybishenko and published by John Wiley & Sons. This book was released on 2015-06-04 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite of many years of studies, predicting fluid flow, heat, and chemical transport in fractured-porous media remains a challenge for scientists and engineers worldwide. This monograph is the third in a series on the dynamics of fluids and transport in fractured rock published by the American Geophysical Union (Geophysical Monograph Series, Vol. 162, 2005; and Geophysical Monograph, No. 122, 2000). This monograph is dedicated to the late Dr. Paul Witherspoon for his seminal influence on the development of ideas and methodologies and the birth of contemporary fractured rock hydrogeology, including such fundamental and applied problems as environmental remediation; exploitation of oil, gas, and geothermal resources; disposal of spent nuclear fuel; and geotechnical engineering. This monograph addresses fundamental and applied scientific questions and is intended to assist scientists and practitioners bridge gaps in the current scientific knowledge in the areas of theoretical fluids dynamics, field measurements, and experiments for different practical applications. Readers of this book will include researchers, engineers, and professionals within academia, Federal agencies, and industry, as well as graduate/undergraduate students involved in theoretical, experimental, and numerical modeling studies of fluid dynamics and reactive chemical transport in the unsaturated and saturated zones, including studies pertaining to petroleum and geothermal reservoirs, environmental management and remediation, mining, gas storage, and radioactive waste isolation in underground repositories. Volume highlights include discussions of the following: Fundamentals of using a complex systems approach to describe flow and transport in fractured-porous media. Methods of Field Measurements and Experiments Collective behavior and emergent properties of complex fractured rock systems Connection to the surrounding environment Multi-disciplinary research for different applications

Download or read book Environmental Forensics written by Robert D. Morrison and published by Elsevier. This book was released on 2010-08-04 with total page 579 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental forensics is the application of scientific techniques for the purpose of identifying the source and age of a contaminant. Over the past several years, this study has been expanding as a course of study in academia, government and commercial markets. The US Environmental Protection Agency (EPA), Federal Bureau of Investigation (FBI), and Federal Emergency Management Agency (FEMA) are among the governmental agencies that utilize the study of environmental forensics to ensure national security and to ensure that companies are complying with standards. Even the International Network for Environmental Compliance and Enforcement (INECE), a group supported by the European Commission and the World Bank, utilizes the study of environmental forensics as it applies to terror threats.This title is a hands-on guide for environmental scientists, engineers, consultants and industrial scientists to identify the origin and age of a contaminant in the environment and the issues involved in the process. An expansion of the authors’ first title with Academic Press, Introduction to Environmental Forensics, this is a state-of-the-art reference for those exploring the scientific techniques available. Up-to-date compendium for referencing forensic techniques unique to particular contaminants. International scientific unit system Contributors from around the world providing international examples and case studies.

Download or read book The Effect of Sedimentation on Plutonium Transport in Fourmile Branch written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major mechanisms of radioactive material transport and fate in surface water are sources, dilution, advection and dispersion of radionuclides by flow and surface waves, radionuclide decay, and interaction between sediment and radionuclides. STREAM II, an aqueous transport module of the Savannah River Site emergency response WIND system, accounts for the source term, and the effects of dilution, advection and dispersion. Although the model has the capability to account for nuclear decay, due to the short time interval of interest for emergency response, the effect of nuclear decay is very small and so it is not employed. The interactions between the sediment and radionuclides are controlled by the flow conditions and physical and chemical characteristics of the radionuclides and the sediment constituents. The STREAM II version used in emergency response must provide results relatively quickly; it therefore does not model the effects of sediment deposition/resuspension. This study estimates the effects of sediment deposition/resuspension on aqueous plutonium transport in Fourmile Branch. There are no measured data on plutonium transport through surface water available for direct model calibration. Therefore, a literature search was conducted to find the range of plutonium partition coefficients based on laboratory experiments and field measurements. A sensitivity study of the calculated plutonium peak concentrations as a function of the input parameter of partition coefficient was then performed. Finally, an estimation of the plutonium partition coefficient was made for the Fourmile Branch.

Download or read book Site Selection for Surplus Plutonium Disposition Facilities at the Savannah River Site written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study is to identify, assess, and rank potential sites for the proposed Surplus Plutonium Disposition Facilities complex at the Savannah River Site.

Download or read book Assessment of Plutonium in the Savannah River Site Environment Revision 1 written by and published by . This book was released on 1992 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plutonium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fifth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. These are living documents, each to be revised and updated on a two-year schedule. This document describes the sources of plutonium in the environment, its release from SRS, environmental transport and ecological concentration of plutonium, and the radiological impact of SRS releases to the environment. Plutonium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite SNAP 9-A, plane crashes involving nuclear weapons, and small releases from reactors and reprocessing plants. Plutonium has been produced at SRS during the operation of five production reactors and released in small quantities during the processing of fuel and targets in chemical separations facilities. Approximately 0.6 Ci of plutonium was released into streams and about 12 Ci was released to seepage basins, where it was tightly bound by clay in the soil. A smaller quantity, about 3.8 Ci, was released to the atmosphere. Virtually all releases have occurred in F- and H-Area separation facilities. Plutonium concentration and transport mechanisms for the atmosphere, surface water, and ground water releases have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases to the offsite maximum individual can be characterized by a total dose of 15 mrem (atmospheric) and 0.18 mrem (liquid), compared with the dose of 12,960 mrem from non-SRS sources during the same period of time (1954--1989). Plutonium releases from SRS facilities have resulted in a negligible impact to the environment and the population it supports.

Download or read book The Office of Environmental Management Technical Reports written by and published by . This book was released on 1997 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sources Speciation and Mobility of Plutonium and Other Transuranics in the Groundwater at the Savannah River Site written by Ken O. Buesseler and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: This annual report summarizes work to date on our EMSP project: Sources, Speciation and Mobility of Plutonium and Other Transuranics in the Groundwater at the Savannah River Site? (Sept. 2003-Sept. 2006 SIGNIFICANCE TO DOE EMSP Migration of plutonium in the environment is a major issue at several DOE sites (Riley and Zachara, 1992)). As such, fundamental data concerning the interactions between various chemical forms of plutonium with compounds in the environment are essential for predicting Pu's behavior in the aqueous environment. Our research has focused on two important DOE sites, namely the Savannah River Site and the Hanford Site, and at both sites we see no need to invoke colloid facilitated transport to explain Pu groundwater distributions. This conclusion has important practical implications because much of the uncertainty associated with Pu subsurface transport, including at the Hanford Site (Mann et al. 1998) and the SRS (McDowell et al., 2000) is attributed directly to the uncertainty associated with the role that mobile colloids may or may not play in transporting Pu.

Download or read book PEIS Upgrade Data Report on Plutonium Storage at the Savannah River Site written by United States. Department of Energy and published by . This book was released on 1996 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Entretien entre le maire municipal le ma tre d cole d une commune du d partement du Mont Terrible sur le d part des pr tres qui on refus de pr ter le serment civique written by and published by . This book was released on 1798 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plutonium Mobilization from Sedimentary Sources to Solution in the Marine Environment written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Inventories of plutonium radionuclides greatly in excess of global fallout levels persists in the benthic environments of Bikini and Eniwetok Atolls. It now appears that the atolls have reached a chemical steadystate condition with respect to the partitioning of /sup 239 +240/Pu between solution and solid phases of the environment. The mobilized /sup 239 +240/Pu has solute-like characteristics, passes rapidly and readily through dialysis membranes, has adsorption characteristics similar to those of fallout plutonium in the open ocean, and exists in solution primarily as some oxidized +5 or +6 chemical species. Water-column profiles of /sup 239 +240/Pu taken outside the atolls show a plutonium excess in the deep water mass. This remobilized /sup 239 +240/Pu possibly originates from the contaminated sediments previously deposited on the outer slopes of the atolls and surrounding basins.

Download or read book Sources Speciation and Mobility of Plutonium and Other Transuranics in the Groudwarter at the Savannah River Site written by Ken O. Buesseler and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This annual report summarizes work to date on our EMSP project:?Sources, Speciation and Mobility of Plutonium and Other Transuranics in the Groundwater at the Savannah River Site (Sept. 2003-Sept. 2006). Our research focus is to further evaluate the sources and fate of Pu and other transuranics in groundwater at the Savannah River Site (SRS). Our overarching goal is to understand Pu speciation and mobility well enough to support safe remediation, containment and long term stewardship at any site with transuranic wastes and sources. Methods developed under prior funding for the determination Pu isotopes, oxidation state and size fractionation in groundwater are providing the best direct evidence for rejecting or not, hypotheses concerning whether colloids enhance the transport of Pu and other transuranics in groundwater. Survey samples collected in the fall of 2003 from F-area well FSB 78 had a 240/239 Pu atom ratio 7.087 +/-0.048 and reflects the continued presences of decayed 244Cm. In October 2004, we returned to the F-area and completed comprehensive field sampling of 7 wells. Field experiments included 6 different extraction rates at well 92D to test sensitivity to artifacts related to well pumping rates, and an aging experiment to evaluate Pu behavior by re-oxidation of reducing groundwater. Sampling of Pond B was included in the site visit to explore unique conditions of redox potential on Pu within the pond. To date, more than 70 Pu redox and whole water samples have been processed and are awaiting analysis at PNNL. Also, five samples from our 1998 visit are undergoing chemistry at PNNL to directly measure Cm with analysis of 2004 samples to follow. Work is continuing to evaluate particle affinity under controlled conditions and a site specific groundwater transport model which we will apply to our lab and field data to obtain a better understanding of the importance of these processes on Pu transport.

Download or read book Groundwater Flow and Tritium Migration in Coastal Plain Sediments Savannah River Site South Carolina written by and published by . This book was released on 1998 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Groundwater modeling was performed to assess groundwater flow and contaminant migration for a tritium plume at the Savannah River Site (SRS). The study supports the Corrective Measures Study and Interim Action Plan regulatory documents for the Old Radioactive Waste Burial Ground (ORWBG). Modeling scenarios were designed to provide data for an economic analysis of alternatives, and subsequently evaluate the effectiveness of the selected remedial technologies for tritium reduction to surface waters. Scenarios assessed include no action, vertical and surface barriers, pump-treat-reinject, and vertical recirculation wells. Hydrostratigraphic units in the area consist of fluvial, deltaic, and shallow marine sand, mud, and calcareous sediments that exhibit abrupt facies changes over short distances. The complex heterogeneity of the sediments, along with characterization data, and tritium contaminant source data required a three-dimensional model be developed in order to accurately illustrate the size, shape and orientation of the plume. Results demonstrate that the shallow confining zone in the region controls the migration path of the plume. The size and shape of the plume were modeled in three-dimensions using detailed core, geophysical and cone-penetrometer data, depth-discrete contaminant data, monitoring well data, and seepline/surface water samples. Three-dimensional tritium plume maps were created for the>20,000,>500 and>50 pCi/ml concentration levels. The three-dimensional plume maps and volumetric calculations indicate that 63 percent of the total activity and 12 percent of the volume above 50 pCi/ml resides in a layer less than 6-m thick riding on top of the shallow confining zone.

Download or read book Department of Energy Plutonium ES H Vulnerability Assessment Savannah River Site Interim Compensatory Measures written by and published by . This book was released on 1994 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: