Download or read book Assessment of Hexavalent Chromium Natural Attenuation for the Hanford Site 100 Area written by and published by . This book was released on 2015 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hexavalent chromium (Cr(VI)) plumes are present in the 100 Area at the Hanford Site. Remediation efforts are under way with objectives of restoring the groundwater to meet the drinking-water standard (48 æg/L) and protecting the Columbia River by ensuring that discharge of groundwater to the river is below the surface-water quality standard (10 æg/L). Current remedies include application of Pump-and-Treat (P & T) at the 100-D, 100-H, and 100-K Areas and Monitored Natural Attenuation (MNA) at the 100-F/IU Area. Remedy selection is still under way at the other 100 Areas. Additional information about the natural attenuation processes for Cr(VI) is important in all of these cases. In this study, laboratory experiments were conducted to demonstrate and quantify natural attenuation mechanisms using 100 Area sediments and groundwater conditions.

Download or read book Evaluation of Chromium Speciation and Transport Characteristics in the Hanford Site 100D and 100H Areas written by and published by . This book was released on 1995 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Field and laboratory investigations have been conducted to define the fate and transport characteristics of chromium contamination present in the 100D/H Areas of the Hanford Site. This information is relevant to assessing the impact of the release of hexavalent chromium to the Columbia River. Included in this study was the determination of the concentration and aqueous speciation of chromium in the unconfined acquifer and an assessment of potential changes in speciation as groundwater passes through the river/acquifer transition zone and mixes with the Columbia River. The results of this study indicate that chromium present within the Hanford acquifer is predominantly in the oxidized hexavalent state. Chromium is apparently stable in the oxidized form owing to its lack of organic matter within the acquifer. A portion of the chromium is removed as groundwater passes through the transition zone due to reduction and precipitation associated with sediment/water interaction processes. Chemical data collected from seep water samples, however, suggests, that most of the hexavalent chromium ultimately discharges into the Columbia River. Dilution of hexavalent chromium subsequently occurs during the mixing of groundwater and river water, with relatively little change taking place in speciation.

Download or read book Natural Attenuation of Hexavalent Chromium in Ground Water and Soils written by Carl D. Palmer and published by . This book was released on 1994 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Engineering Tools for Environmental Risk Management written by Katalin Gruiz and published by CRC Press. This book was released on 2019-01-08 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: The four volumes of the book series "Engineering Tools for Environmental Risk Management" deal with environmental management, assessment & monitoring tools, environmental toxicology and risk reduction technologies. This last volume focuses on engineering solutions usually needed for industrial contaminated sites, where nature’s self-remediation is inefficient or too slow. The success of remediation depends on the selection of an increasing number of conventional and innovative methods. This volume classifies the remedial technologies and describes the reactor approach to understand and manage in situ technologies similarly to reactor-based technologies. Technology types include physicochemical, biological or ecological solutions, where near-natural, sustainable remediation has priority. A special chapter is devoted to natural attenuation, where natural changes can help achieve clean-up objectives. Natural attenuation and biological and ecological remediation establish a serial range of technologies from monitoring only to fully controlled interventions, using ‘ just’ the natural ecosystem or sophisticated artificial living systems. Passive artificial ecosystems and biodegradation-based remediation – in addition to natural attenuation – demonstrate the use of these ‘green’ technologies and how engineering intervention should be kept at a minimum to limit damage to the environment and create a harmonious ecosystem. Remediation of sites contaminated with organic substances is analyzed in detail including biological and physicochemical methods. Comprehensive management of pollution by inorganic contaminants from the mining industry, leaching and bioleaching and acid mine drainage is studied in general and specifically in the case of an abandoned mine in Hungary where the innovative technology of combined chemical and phytostabilization has been applied. The series of technologies is completed by electrochemical remediation and nanotechnologies. Monitoring, verification and sustainability analysis of remediation provide a comprehensive overview of the management aspect of environmental risk reduction by remediation. This book series focuses on the state of knowledge about the environment and its conscious and structured application in environmental engineering, management and decision making.

Download or read book Sampling and Analysis Instruction for Evaluation of Hexavalent Chromium in Soil Near the 100 D Area Sodium Dichromate Transfer Station Railroad written by Wendy S. Thompson and published by . This book was released on 2004 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results from Recent Science and Technology Investigations Targeting Chromium in the 100D Area Hanford Site Washington Usa written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Sodium dichromate was used in Hanford's 100D Area during the reactor operations period of 1950 to 1964 to retard corrosion in the reactor cooling systems. Some of the sodium dichromate was released to the environment by spills and/or leaks from pipelines used to deliver the chemical to water treatment plants in the area. As a result, hexavalent chromium [Cr(VI)] has migrated through the vadose zone to the groundwater and contaminated nearly 1 km2 of groundwater to above the drinking water standard of 48 [mu]g/L. Three technology tests have recently been completed in this area to characterize the source area of the plumes and evaluate alternative methods to remove Cr(VI) from groundwater. These are (1) refine the source area of the southern plume; (2) test electrocoagulation as an alternative groundwater treatment technology; and (3) test the ability to repair a permeable reactive barrier by injecting micron or nanometer-size zero-valent iron (ZVI). The projects were funded by the US Department of Energy as part of a program to interject new technologies and accelerate active cleanup. Groundwater monitoring over the past 10 years has shown that Cr(VI) concentrations in the southern plume have not significantly diminished, strongly indicating a continuing source. Eleven groundwater wells were installed in 2007 and 2008 near a suspected source area and monitored for Cr(VI) and groundwater levels. Interpretation of these data has led to refinement of the source area location to an area of less than 1 hectare (ha, 2.5 acres). Vadose zone soil samples collected during drilling did not discover significant concentrations of Cr(VI), indicating the source is localized, with a narrow wetted path from the surface to the water table. Electrocoagulation was evaluated through a pilot-scale treatability test. Over 8 million liters of groundwater were treated to Cr(VI) concentrations of ≤20 [mu]g/L. The test determined that this technology has the potential to treat Cr(VI) to these low levels, but system reliability and operational complexity rendered electrocoagulation less cost effective than the baseline technology of ion exchange. Laboratory and field tests were conducted to evaluate the practicality of injecting ZVI into the aquifer to increase the lifespan and effectiveness of an existing permeable reactive barrier. From a database of 30 ZVI materials, 6 were chosen and tested in the laboratory to determine their geochemical and physical performance under simulated 100D aquifer conditions. The best-performing ZVI was injected into the aquifer and met the primary goals of communicating the iron at least 7 meters from the injection point and reducing the aquifer to transform mobile Cr(VI) to trivalent chromium Cr(III), which is effectively immobile in the aquifer.

Download or read book A Field Laboratory and Modeling Study of Natural Attenuation Processes Affecting the Fate and Transport of Hexavalent Chromium in a Redox Variable Groundwater Environment written by Lucas Ammi Hellerich and published by . This book was released on 2004 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In Situ Treatment of Soil and Groundwater Contaminated with Chromium written by National Risk Management Research Laboratory (U.S.) and published by . This book was released on 2000 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Agronomy written by Donald L. Sparks and published by Elsevier. This book was released on 2022-10-11 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Agronomy, Volume 176, the latest release in this leading reference on agronomy, contains a variety of updates and highlights new advances in the field. Each chapter is written by an international board of authors. Includes numerous, timely, state-of-the-art reviews on the latest advancements in agronomy Features distinguished, well recognized authors from around the world Builds upon this venerable and iconic review series Covers the extensive variety and breadth of subject matter in the crop and soil sciences

Download or read book Remediation of Legacy Hazardous and Nuclear Industrial Sites written by Stuart T. Arm and published by CRC Press. This book was released on 2024-09-12 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: Remediation of Legacy Hazardous and Nuclear Industrial Sites provides an overview of the key elements involved in remediating complex waste sites using the Hanford nuclear site as a case study. Hanford is one of the most complex waste sites in the world and has examples of most, if not all, characteristics of the complex waste sites that exist globally. This book is aimed at a non-technical audience and describes the stages of remediation based on general RCRA/CERCLA processes, from establishing a strategy that includes all stakeholders to site assessment, waste treatment and disposal, and long-term monitoring. Features: Informs a non-technical audience of the important elements involved in complex waste site remediation Employs the Hanford Site as a case study throughout to explain real-world applications of remediation steps Connects the “human” element to the technical aspects through interviews with key current and retired individuals at the Hanford Site Includes discussion of stakeholders and the engagement process in remediation Demonstrates how all elements of complex waste site remediation from demolition of buildings to groundwater management are interrelated Focuses on broader technical and sociopolitical challenges for remediation of a contaminated site Aimed at a broad audience, this book offers approachable guidance to technical and non-technical readers through a series of real-world examples that cover each important step in the complex waste cleanup process.

Download or read book Treatability Study of in Situ Technologies for Remediation of Hexavalent Chromium in Groundwater at the Puchack Well Field Superfund Site New Jersey written by Vincent R. Vermeul and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Hexavalent Chromium Flux to Groundwater at the 100 C 7 written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Deep excavation of soil has been conducted at the 100-C-7 and 100-C-7:1 waste sites within the 100-BC Operable Unit at the Department of Energy (DOE) Hanford Site to remove hexavalent chromium (Cr(VI)) contamination with the excavations reaching to near the water table. Soil sampling showed that Cr(VI) contamination was still present at the bottom of the 100-C-7:1 excavation. In addition, Cr(VI) concentrations in a downgradient monitoring well have shown a transient spike of increased Cr(VI) concentration following initiation of excavation. Potentially, the increased Cr(VI) concentrations in the downgradient monitoring well are due to Cr(VI) from the excavation site. However, data were needed to evaluate this possibility and to quantify the overall impact of the 100-C-7:1 excavation site on groundwater. Data collected from a network of aquifer tubes installed across the floor of the 100-C-7:1 excavation and from temporary wells installed at the bottom of the entrance ramp to the excavation were used to evaluate Cr(VI) releases into the aquifer and to estimate local-scale hydraulic properties and groundwater flow velocity.

Download or read book SCIENCE AND TECHNOLOGY ACTIVITIES FOR CHROMIUM IN THE 100 AREAS written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: {Sm_bullet} Primary Objective: Protect the Columbia River - Focus is control and treatment of contamination at or near the shoreline, which is influenced by bank storage {sm_bullet} Secondary Objective: Reduce hexavalent chromium to 48 parts per billion (ppb) in aquifer (drinking water standard) - Large plumes with isolated areas of high chromium concentrations ( 40,000 ppb), - Unknown source location(s); probably originating in reactor operation areas.

Download or read book ADVANCES IN HEXAVALENT CHROMIUM REMOVAL AT HANFORD written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: At the Hanford Site, chromium was used as a corrosion inhibitor in the reactor cooling water and was introduced into the groundwater as a result of planned and unplanned discharges from reactors during plutonium production since 1944. Beginning in 1995, groundwater treatment methods were evaluated leading to the use of pump and treat facilities with ion exchange using Dowex 21 K, a regenerable strong base anion exchange resin. This required regeneration of the resin, which is currently performed offsite. Resin was installed in a 4 vessel train, with resin removal required from the lead vessel approximately once a month. In 2007, there were 8 trains (32 vessels) in operation. In 2008, DOE recognized that regulatory agreements would require significant expansion in the groundwater chromium treatment capacity. Previous experience from one of the DOE project managers led to identification of a possible alternative resin, and the contractor was requested to evaluate alternative resins for both cost and programmatic risk reductions. Testing was performed onsite in 2009 and 2010, using a variety of potential resins in two separate facilities with groundwater from specific remediation sites to demonstrate resin performance in the specific groundwater chemistry at each site. The testing demonstrated that a weak base anion single-use resin, ResinTech SIR-700, was effective at removing chromium, had a significantly higher capacity, could be disposed of efficiently on site, and would eliminate the complexities and programmatic risks from sampling, packaging, transportation and return of resin for regeneration. This resin was installed in Hanford's newest groundwater treatment facility, called 100-DX, which began operations in November, 2010, and used in a sister facility, 100-HX, which started up in September of 2011. This increased chromium treatment capacity to 25 trains (100 vessels). The resin is also being tested in existing facilities that utilize Dowex 21 K for conversion to the new resin. This paper will describe the results of the testing, performance in the facilities, continued optimization in the pump and treat facilities, and the estimated savings and non-tangible benefits of the conversion.

Download or read book Results of Hexavalent Chromium Sampling Near 100 D Area Sodium Dichromate Transfer Station Railroad Tracks written by K. A. Anselm and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sampling and Analysis Instructions for Investigating Chromium Groundwater Contamination in the 600 Area Between 100 D and 100 H written by Stephen Harvey Hall and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Trace Elements in Waterlogged Soils and Sediments written by Jörg Rinklebe and published by CRC Press. This book was released on 2016-08-19 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many wetlands around the world act as sinks for pollutants, in particular for trace elements. In comparison to terrestrial environments, wetlands are still far less studied. A collaborative effort among world experts, this book brings the current knowledge concerning trace elements in temporary waterlogged soils and sediments together. It discusses factors controlling the dynamics and release kinetics of trace elements and their underlying biogeochemical processes. It also discusses current technologies for remediating sites contaminated with trace metals, and the role of bioavailability in risk assessment and regulatory decision making. This book is intended for professionals around the world in disciplines related to contaminant bioavailability in aquatic organisms, contaminant fate and transport, remediation technologies, and risk assessment of aquatic and wetland ecosystems.