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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

The Department of Energy Savannah River Operations Office Savannah River National Laboratory Unmanned Aircraft System Aviation Implementation Plan

The Department of Energy Savannah River Operations Office Savannah River National Laboratory Unmanned Aircraft System Aviation Implementation Plan was written to provide guidance for the safe, efficient, and lawful operation of the SRNL small Unmanned Aircraft System (sUAS) Program. It shall be the intent of every sUAS remote pilot in command to make reasonable effort not to invade a person's reasonable expectation of privacy when operating the sUAS. SRS sUAS operations will be conducted in accordance all applicable Federal Aviation Administration (FAA), Department of Energy (DOE), and DOE-Savannah River Operations Office (DOE-SR) regulations, policies and procedures. All sUAS operations will be conducted in accordance with the applicable FAA issued DOE Certificate of Authorization (COA) and be approved by the applicable DOE-SR Flight Readiness Review Board (FRRB). The scope of this document is limited to remote pilots in command of sUAS's in support of the DOE, DOE-SR, or SRS missions, research & development (R&D) and national security strategic initiatives supported by SRNL, and other approved missions as required in the US National Airspace (NAS) as defined by the FAA.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2012

Savannah River Site, Liquid Waste Program, Savannah River Remediation American Recovery and Reinvestment Act Benefits and Lessons Learned - 12559

Utilizing funding provided by the American Recovery and Reinvestment Act (ARRA), the Liquid Waste Program at Savannah River site successfully executed forty-one design, procurement, construction, and operating activities in the period from September 2009 through December 2011. Project Management of the program included noteworthy practices involving safety, integrated project teams, communication, and cost, schedule and risk management. Significant upgrades to plant capacity, progress toward waste tank closure and procurement of needed infrastructure were accomplished. Over 1.5 million hours were worked without a single lost work day case. Lessons Learned were continually identified and applied to enhance the program. Investment of Recovery Act monies into the Liquid Waste Program has ensured continued success in the disposition of radioactive wastes and the closure of high level waste tanks at SRS. The funding of a portion of the Liquid Waste Program at SRS by ARRA was a major success. Significant upgrades to plant capacity, progress toward waste tank closure and procurement of needed infrastructure was accomplished. Integrated Project Teams ensured quality products and services were provided to the Operations customers. Over 1.5 million hours were worked without a single lost work day case. Lessons Learned were continually reviewed and reapplied to enhance the program. Investment of Recovery Act monies into the Liquid Waste Program has ensured continued success in the disposition of radioactive wastes and the closure of high level waste tanks at SRS. (authors)

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DOE OSTI2017

Savannah River Remediation Liquid Waste Operations Lifecycle Savings through a Lean Business System at the Savannah River Site - 17245

Savannah River Remediation (SRR) was contracted by the U.S. Department of Energy (DOE) to manage its liquid waste project at the Savannah River Site. The liquid waste project is a unique, high hazard nuclear waste treatment and disposal facility consisting of 51 one million-gallon underground waste tanks, a solvent extraction processing unit, a vitrification facility for the highest radioactive waste, and a grout solidification and disposal facility for lower radioactive decontaminated salt solution. Our Project mission is to treat the nuclear waste and close the associated storage and treatment facilities, of which, 8 tanks have been closed to date. The Lean philosophy took root decades ago in the manufacturing sector and started with the work of W. Edwards Deming and his contemporaries. In more recent years the process has matured in the Toyota Production System and migrated into fields as diverse as services industries, health-care, and now the DOE complex. At SRR, a Lean business management system was adopted to address site inefficiencies, aging infrastructure concerns and budget constraints. With yearly escalation and flat budgets, continuous improvement is taking on a larger role - improving the work accomplished for each dollar. This paper focuses on the program results achieved to date, including the lifecycle savings identified through the Rapid Improvement Event (RIE) process. The RIE process is a Lean tool which creates a cross-functional team to analyze, develop and implement improvements for a given process. DOE-EM has recently emphasized the value of contractor's continuous improvement programs through their implementation of Plan of Action and Milestone (POAM): Goal 2 (Increase Efficiency/Improve Performance) Reduce EM Operations Cost in FY16. POAM Goal 2 was a FY 16 effort to achieve 5% cost savings across most programs. This past year's cost savings initiatives will likely become a trend as DOE and its contractors look to do more with less. In support of our own business objectives, as well as, DOE's motivation to improve efficiencies, SRR has held over one hundred formal Lean events and dozens of 5S events that have driven improvement across the Project, including tank closure and production facilities. These improvements have significantly reduced the time required to process material and achieve the overall goal of hazard reduction and tank closure. (authors)

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DOE OSTI2023

Biogeochemistry of Pond B (Savannah River Site, South Carolina, USA): Sediment Core, Total extraction data, Pond B Savannah River Site July 2019. Subsurface Biogeochemistry of Actinides SFA

Pond B at Savannah River Site (SRS, South Carolina) is a monomictic reservoir that received SRS R reactor cooling water from 1961–1964. Previous studies conducted between the 1980s–1990s on the water column and sediments of Pond B measured trace amounts of Pu (33 MBq 238Pu and 430 MBq 239,240Pu), 241Am, and 137Cs. Since then, the pond has been relatively isolated and the radionuclide concentrations have not been monitored over time. Herein, about 30 years after the last publication on Pond B, we are re-evaluating the geochemistry and radionuclide distribution within Pond B at four locations along a horizontal transect from the inlet to outlet.This study investigated the distribution of anthropogenic radionuclides Pu-239 and Cs-137 along with total organic carbon, iron, and trace element in contaminated sediments of Pond B at the Savannah River Site (SRS). Pond B received reactor cooling water from 1961 to 1964, and trace amounts of Pu-239 and Cs-137 during operations. Our study collected sediment cores to determine concentrations of Pu-239, Cs-137, and major and minor elements in solid phase, pore water and an electrochemical method was used on wet cores to determine dissolved elemental concentrations.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Determining Cs-137 Background body burdens for Wild Pigs At Savannah River Site

Savannah River Site (SRS) is a unique U.S. Department of Energy facility in that most of the 310-square miles of land has not be industrialized since operations began in 1953. This has allowed abundant, undisturbed vegetation structure to exists as well as an increase in herd sizes among wildlife populations onsite. Cs-137 is widespread across SRS due to the production of nuclear materials, but is mostly from global atmospheric fallout from nuclear weapons testing. Due to most of SRS being undisturbed land, the concentrations of Cs-137 are higher on site than off site. The SRS began conducting annual deer harvests that were open to the public beginning in 1965. All animals harvested during these hunts are monitored for Cs-137, which is measured using a Sodium Iodide detector. There has been an effective method for calculating the background Cs-137 body burden for the deer population at the SRS, developed by Gaines and Novak using data collected during hunts and gamma overflight data to determine the areas contaminated by site activities. For animals that have a Cs-137 concentration above the established background level, a dose is assigned to the hunter. By applying the same method for wild pigs using data collected from hunts, gamma overflight, and developing a site-specific home range of wild pigs, we were able to calculate the Cs-137 background body burden concentrations of wild pigs on site. Objectives: Develop site-specific home range for wild pigs at SRS; Determine the average concentrations of Cs-137 in wild pigs from background; Use Gaines and Novak method for determining background Cs-137 body burdens wild pigs on SRS. Methods and Materials: Development of site-specific home range of wild pigs was determined to be 2.5 miles using: Four studies conducted between 1969 and 1992 for the SRS wild pig population. (Mayer and Brisbin) The background compartments were determined using: Gamma overflight data showing contaminated areas; Site-specific home range of the wild pigs. Results and Conclusion: All data were generated through the JMP software to provide a histogram and summary statistics. The estimate of an upper tolerance limit for the background contamination with 95% confidence is 1.965 pCi/g for the wild pigs. This means that for wild pigs on SRS from the background compartments are expected to have Cs-137 concentrations of less than 1.965 pCi/g. The current background for the deer is 2.59 pCi/g. For the background compartments Cs-137 concentrations from 2012-2018: Mean: 0.815 pCi/g, Maximum: 2.341 pCi/g, Minimum: -0.704 pCi/g.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2013

Facility Utilization and Risk Analysis for Remediation of Legacy Transuranic Waste at the Savannah River Site - 13572

Savannah River Nuclear Solutions (SRNS) completed the Accelerated TRU Project for remediating legacy waste at the Savannah River Site with significant cost and schedule efficiencies due to early identification of resources and utilization of risk matrices. Initial project planning included identification of existing facilities that could be modified to meet the technical requirements needed for repackaging and remediating the waste. The project schedule was then optimized by utilization of risk matrices that identified alternate strategies and parallel processing paths which drove the overall success of the project. Early completion of the Accelerated TRU Project allowed SRNS to pursue stretch goals associated with remediating very difficult TRU waste such as concrete casks from the hot cells in the Savannah River National Laboratory. Project planning for stretch goals also utilized existing facilities and the risk matrices. The Accelerated TRU project and stretch goals were funded under the American Recovery and Reinvestment Act (ARRA). (authors)

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

2015 Assessment of Mercury in the Savannah River Site Environment and Responses to the Agency for Toxic Substances and Disease Registry 2012 Report on Assessment of Biota Exposure to Mercury Originating from the Savannah River Site

The purpose of this report is to 1) update previous Savannah River National Laboratory (SRNL) assessment reports (Kvartek et al. 1994 and Halverson et al. 2008) on the fate of mercury in the Savannah River Site (SRS) environment and 2) address comments and recommendations from the review of SRS by the Agency for Toxic Substances and Disease Registry (ATSDR) concerning the evaluation of exposures to contaminants in biota originating from the SRS. The ATSDR reviewed and evaluated data from SRS, South Carolina Department of Health & Environmental Control (SCDHEC) and the Georgia Department of Natural Resources (GDNR) concerning the non-radioactive contaminant mercury. This report will provide a response and update to conclusions and recommendations made by the ATSDR.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Survey of Aquatic Turtles on the Savannah River Site, South Carolina, USA, for Prevalence of Ranavirus

Ranaviruses have the ability to infect amphibians, fish, and reptiles, and have caused multiple amphibian die-off events in the United States (U. S.) and Europe. Furthermore, their prevalence in amphibian populations is much more commonly studied than in chelonian populations. We examined blood samples (N=286) from eight aquatic turtle species collected during 2008-2014 on the Savannah River Site (SRS), South Carolina as part of long-term mark-recapture efforts. Previous studies in the southeastern US found high prevalence of ranavirus in amphibians, but we did not detect ranavirus in any of the turtles sampled, suggesting low presence, prevalence, or both in aquatic turtles across the SRS during the years tested.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Acquisition and Implementation of a Comprehensive Environmental Permits Linking Tool at Savannah River Site - 20234

Historically, Savannah River Nuclear Solutions LLC (SRNS) tracked environmental regulatory commitments and the requirements from hundreds of permits at the Savannah River Site (SRS) using several separate methods, making integrated compliance assurance cumbersome and labor-intensive. When SRNS experienced an increase in environmental issues in 2017, SRNS management and U.S. Department of Energy - Savannah River (DOE-SR) management decided a single, proactive approach was needed to capture environmental permit information (including regulations, Consent Orders, DOE Orders, and any other state or federally issued statement of requirements), track the tasks necessary to ensure compliance with these requirements, and thereby mitigate the risk of noncompliance. SRNS developed a list of mandatory objectives that the tool must meet to function as a Comprehensive Environmental Permits Linking Tool (CEPLT). A key requirement was the ability to map Site permits to their governed locations and display the associated requirements at the compliance point (e.g., outfall, stack, waste unit, etc.). Several options included modifying existing onsite resources, building a custom onsite solution, purchasing an off-the-shelf solution, and contracting an offsite developer to build a custom solution. SRNS concluded an off-the-shelf solution with configuration and customization options would provide the flexibility to fit the unique needs of Savannah River Site (SRS) while taking advantage of industry-tested software and providing a reduced deployment timeline. SRNS chose Gensuite{sup R} a, a cloud-based solution that offers numerous a la carte applications in the environmental, health, and safety arenas, as the best candidate. SRNS selected three (3) integrated applications (Compliance Calendar, Permit Manager, and Mapper) to function as the CEPLT. The Compliance Calendar module allows for creation and tracking of regulatory commitment tasks assigned to responsible environmental professionals. Permit Manager organizes permits and other requirement documents, linking the commitments in each to Compliance Calendar tasks and/or implementing procedures. Mapper provides GIS capability for mapping the data from the other two modules to their physical onsite locations. The CEPLT was configured to allow for other SRS Site Tenants to eventually utilize the applications. Additionally, DOE-SR uses the CEPLT to provide an overview of contractor environmental compliance activities and to organize DOE-specific documents and tasks. The CEPLT fulfilled the requirement of meeting current compliance needs as well as providing the ability to grow as new organizations are incorporated and functionality is expanded. SRNS now uses the CEPLT to more effectively manage permit requirements, improve knowledge transfer, and increase the Site's overall protection of the environment, the Site worker, and the public. Possible future uses of the system include integration of mobile applications for timely communication of potential non-compliant conditions and DOE complex-wide deployment allowing for enhanced DOE site and Head Quarters oversight. Implementation of CEPLT will result in cost savings, both in terms of dollars and man-hours. (authors)

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DOE OSTI2025

Selected Chemical Engineering Applications in Nuclear-Waste Processing at the Savannah River Site

The Savannah River Site has been successfully processing and immobilizing nuclear waste since 1996. However, recent developments in both the scientific understanding of chemical principles and the engineering of immobilizing nuclear-waste systems demand a review of the state of the art. These recent advances have significance to other locations that immobilize nuclear waste. Here, the subject matter of this review may find special applicability to chemical engineers interested in hazardous chemical processes (such as processing toxic and radioactive nuclear waste) and to those in the nuclear industry curious about current research in nuclear-waste processing at a site that has eclipsed the quarter-century mark of large-scale (136 million L total) nuclear-waste processing.

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DOE OSTI2013

Decommissioning an Active Historical Reactor Facility at the Savannah River Site - 13453

The Savannah River Site (SRS) is an 802 square-kilometer United States Department of Energy (US DOE) nuclear facility located along the Savannah River near Aiken, South Carolina, where Management and Operations are performed by Savannah River Nuclear Solutions (SRNS). In 2004, DOE recognized SRS as structure within the Cold War Historic District of national, state and local significance composed of the first generation of facilities constructed and operated from 1950 through 1989 to produce plutonium and tritium for our nation's defense. DOE agreed to manage the SRS 105-C Reactor Facility as a potentially historic property due to its significance in supporting the U.S. Cold War Mission and for potential for future interpretation. This reactor has five primary areas within it, including a Disassembly Basin (DB) that received irradiated materials from the reactor, cooled them and prepared the components for loading and transport to a Separation Canyon for processing. The 6,317 square meter area was divided into numerous work/storage areas. The walls between the individual basin compartments have narrow vertical openings called 'slots' that permit the transfer of material from one section to another. Data indicated there was over 830 curies of radioactivity associated with the basin sediments and approximately 9.1 M liters of contaminated water, not including a large quantity of activated reactor equipment, scrap metal, and debris on the basin floor. The need for an action was identified in 2010 to reduce risks to personnel in the facility and to eliminate the possible release of contaminants into the environment. The release of DB water could potentially migrate to the aquifer and contaminate groundwater. DOE, its regulators [U. S. Environmental Protection Agency (USEPA)-Region 4 and the South Carolina Department of Health and Environmental Control (SCDHEC)] and the SC Historical Preservation Office (SHPO) agreed/concurred to perform a non-time critical removal action for the In Situ Decommissioning (ISD) of the 105-C Disassembly Basin. ISD consisted of stabilization/isolation of remaining contaminated water, sediment, activated reactor equipment, and scrap metal by filling the DB with underwater non-structural grout to the appropriate (-4.877 meter) grade-level, thence with dry area non-structural grout to the final -10 centimeter level. The roof over the DB was preserved due to its potential historical significance and to prevent the infiltration of precipitation. Forced evaporation was the form of treatment implemented to remove the approximately 9.1 M liters of contaminated basin water. Using specially formulated grouts, irradiated materials and sediment were treated by solidification/isolation thus reducing their mobility, reducing radiation exposure and creating an engineered barrier thereby preventing access to the contaminants. Grouting provided a low permeability barrier to minimize any potential transport of contaminants to the aquifer. Efforts were made to preserve the historical significance of the Reactor in accordance with the National Historic Preservation Act. ISD provides a cost effective means to isolate and contain residual radioactivity from past nuclear operations allowing natural radioactive decay to reduce hazards to manageable levels. This method limits release of radiological contamination to the environment, minimizes radiation exposure to workers, prevents human/animal access to the hazardous substances, and allows for ongoing monitoring of the decommissioned facility. Field construction was initiated in August 2011; evaporator operations commenced January 2012 and ended July 2012 with over 9 M liters of water treated/removed. Over 8,525 cubic meters of grout were placed, completing in August 2012. The project completed with an excellent safety record, on schedule and under budget. (authors)

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DOE OSTI2017

Impacts of glycolate and formate radiolysis and thermolysis on hydrogen generation rate calculations for the Savannah River Site tank farm

Savannah River Remediation (SRR) personnel requested that the Savannah River National Laboratory (SRNL) evaluate available data and determine its applicability to defining the impact of planned glycolate anion additions to Savannah River Site (SRS) High Level Waste (HLW) on Tank Farm flammability (primarily with regard to H 2 production). Flammability evaluations of formate anion, which is already present in SRS waste, were also needed. This report describes the impacts of glycolate and formate radiolysis and thermolysis on Hydrogen Generation Rate (HGR) calculations for the SRS Tank Farm.

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DOE OSTI2026

Utilization of Unmanned Aircraft Systems for Environmental Purposes at the Savannah River Site – 26578

Born in the 1950s, the Savannah River Plant was constructed as a plutonium and tritium production plant. As the Cold War era came and went, a change of direction was signaled when the name of the facility changed from Savannah River Plant to Savannah River Site (1989) – the main mission at Savannah River shifted from “production” to “cleanup.” The Department of Energy is responsible for managing the 310 square miles of land that is the Savannah River Site and the cleanup/remediation activities that occur. The Savannah River National Laboratory utilizes unmanned aircraft systems to assist with some of those environmental monitoring and remediation activities. One function of unmanned aircraft systems at the Savannah River National Laboratory is conducting aerial photography and videography. Various infrastructure evaluations have been performed with unmanned aircraft – facility rooftop inspections, water tower lock verifications, earthen dam surveys, etc. An unmanned aircraft system has been used for progress footage of remediation projects – Dunbarton Bay remediation, Saltstone Disposal Unit construction, etc. Thermal cameras on an unmanned aircraft system are used to help identify cracks/leaks in structures from vantage points not readily accessible by personnel. Virtual tours of different waste units are conducted with unmanned aircraft systems for Site groups and federal/state regulators to save costs and travel time. Additionally, advanced remote sensing technologies are used on unmanned aircraft systems at the Savannah River Site. Light Detection and Ranging uses laser pulses to measure distances to the Earth's surface or other targets to create highly detailed topographic maps that accurately portray terrain (e.g., elevation changes, slopes, and contours). Data collection with a Light Detection and Ranging unit mounted on an unmanned aircraft system is quick and efficient – large-area surveys are conducted in shorter time frames. Because Light Detection and Ranging can penetrate through foliage and vegetation to ground level, it is being used in conjunction with a watershed model to study the General Separations Area of the Site to determine stormwater flow volume and direction, monitor stream stability, and forecast river flow behavior. A hyperspectral camera captures a wide spectrum of electromagnetic wavelengths across numerous narrow bands, beyond what the human eye can see. It provides detailed spectral information about the objects or surfaces in an image, which can be used to identify and analyze materials based on their spectral signatures. A hyperspectral camera mounted on an unmanned aircraft system has been used at the Savannah River Site for non-destructive evaluation of concrete and concrete structures. Unmanned aircraft systems at the Savannah River Site are also used for the application of herbicide on identified rooftops. P-Reactor and R-Reactor are entombed nuclear reactors at the Savannah River Site. Unwanted vegetation is often present on these rooftops – over time roots can penetrate seams, cracks, and joints of the general roof and concrete caps, leading to water ingress and deterioration of the structural components. For time and cost efficiencies as well as in the interest of personnel safety, an unmanned aircraft is used to dispense herbicide on rooftop areas where vegetation is noticed to help alleviate the issues/hazards.

Lorier, Troy [Savannah River National Laboratory (↗
DOE OSTI2013

Integration of Environmental Compliance at the Savannah River Site - 13024

The Savannah River Site (SRS) is a large federal installation hosting diverse missions and multiple organizations with competing regulatory needs. Accordingly, there was a need to integrate environmental compliance strategies to ensure the consistent flow of information between Department of Energy-Savannah River (DOE-SR), the regulatory agencies and other interested parties. In order to meet this objective, DOE and major SRS contractors and tenants have committed to a strategy of collaboratively working together to ensure that a consistent, integrated, and fully coordinated approach to environmental compliance and regulator relationships is maintained. DOE-SR and Savannah River Nuclear Solutions, LLC, the SRS management and operations contractor, have established an environmental compliance integration process that provides for the consistent flow down of requirements to projects, facilities, SRS contractors, and subcontractors as well as the upward flow of information to assist in the early identification and resolution of environmental regulatory issues and enhancement of compliance opportunities. In addition, this process strongly fosters teamwork to collaboratively resolve complex regulatory challenges, promote pollution prevention and waste minimization opportunities to advance site missions in a manner that balances near-term actions with the long-term site vision, while being protective of human health and the environment. Communication tools are being utilized, some with enhancements, to ensure appropriate information is communicated to all levels with environmental responsibility at SRS. SRS internal regulatory integration is accomplished through a variety of informational exchange forums (e.g., Challenges, Opportunities and Resolution (COR) Team, DOE's Joint Site Regulatory Integration Team, and the Senior Environmental Managers Council (SEMC)). SRS communications and problem-solving with the regulatory agencies have been enhanced through formation of an interagency 'SRS Regulatory Integration Team (SRIT)'. The SRIT is a partnership comprised of representatives from DOE-SR (with contractor support), EPA Region 4 and the South Carolina Department of Health and Environmental Control (SCDHEC) and is chartered to develop a consensus understanding of SRS regulatory issues and activities. These forums and a formal environmental compliance integration process improve timely cross-functional decision making, problem solving, information sharing, and issue resolution. The SRS internal process has been formally documented in an Environmental Regulatory Integration Program Description, which is linked to the SRS Environmental Policy and agreed upon by all major contractors, subcontractors and tenants. (authors)

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DOE OSTI2015

Sodium silicate treatment for uranium (vi) bearing groundwater systems at f/h area at savannah river site - 15709

The Savannah River Site (SRS) was one of the most significant manufacturing facilities during the Cold War era for producing nuclear materials. At the end of the Cold War, the Site's mission changed to support the environmental restoration of the Site due to over six decades of research, development, and production of nuclear weapons. Currently SRS is a major hazardous waste management facility responsible for nuclear materials storage, and remediation of contaminated soil and groundwater from radionuclides. This research focuses on controlling the mobilization of the contaminants, specifically uranium (VI) located in groundwater plumes at the Site's F/H Area Seepage Basin, where approximately 1.8 billion gallons of hazardous waste were deposited. Objective: To evaluate the potential use of sodium silicate for uranium removal from the aqueous phase, as well as to restore the pH of the treatment zone. Adding sodium silicate increases the pH of the treatment zone and uranium precipitation is achieved, therefore immobilizing the contaminant. Through a series of experiments the optimal concentration of sodium silicate was investigated. Part 1: An experiment was conducted in order to determine the effect of sodium silicate on the pH of a solution containing Savannah River Site soil and synthetic groundwater replicated after the Site's natural groundwater composition. Each sample was spiked with the appropriate volume from the sodium silicate stock solution in order to achieve final desired sodium silicate concentrations of 10, 20, 40,50,60,70, and 80 parts per million. The samples were placed on a platform shaker for three days during which pH readings were collected in regular intervals to determine which silicate concentration produced a pH in the neutral range (6 > pH < 8). Part 2: A sequential experiment was conducted specifically using 40 and 50 ppm of sodium silicate with Savannah River Site soil, synthetic groundwater, and 0.5 ppm of uranium (VI), in order to investigate the removal of uranium in the aqueous phase via precipitation. Samples were extracted and categorized into a filtered and non-filtered control group. Each sample was diluted 1:20 with 1% nitric acid and analyzed using the Kinetic Phosphorescence Analyzer (KPA) in order to measure uranium concentrations in the supernatant. By measuring the concentration of uranium in the supernatant the percent removal is obtained for the comparison between the filtered and non-filtered samples, revealing the amount of uranium precipitation that occurred for each silicate concentration. Results: A sodium silicate concentration of between 40-50 ppm proved ideal for achieving uranium precipitation and creating a circum-neutral pH environment in the aqueous phase. 50 ppm achieved the larger percent of uranium precipitation with a range of 30-50% removal for the filtered samples and between 60-95% removal for the non-filtered samples. A large difference between the removal of filtered and non- filtered samples from the same day was observed for both sodium silicate concentrations tested, indicating that there is a considerable amount of uranium species retained in the filter. The addition of sodium silicate proved effective in the removal of uranium precipitation from the aqueous phase. Future work: Determine potential re-solubilization of uranium concentrations; Examine mineralogy and surface morphology of dried precipitate using XRD and SEM/EDS.

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