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Screening of Potential Remediation Methods for the 200-ZP-1 Operable Unit at the Hanford Site

Description: A screening-level evaluation of potential remediation methods for application to the contaminants of concern (COC) in the 200-ZP-1 Operable Unit at the Hanford Site was conducted based on the methods outlined in the Guidance for Conducting Remedial Investigations and Feasibility Studies under CERCLA Interim Final. The scope of this screening was to identify the most promising remediation methods for use in the more detailed analysis of remediation alternatives that will be conducted as part of the full feasibility study. The screening evaluation was conducted for the primary COC (potential major risk drivers). COC with similar properties were grouped for the screening evaluation. The screening evaluation was conducted in two primary steps. The initial screening step evaluated potential remediation methods based on whether they can be effectively applied within the environmental setting of the 200-ZP-1 Operable Unit for the specified contaminants. In the second step, potential remediation methods were screened using scoping calculations to estimate the scale of infrastructure, overall quantities of reagents, and conceptual approach for applying the method for each defined grouping of COC. Based on these estimates, each method was screened with respect to effectiveness, implementability, and relative cost categories of the CERCLA feasibility study screening process defined in EPA guidance.
Date: August 7, 2006
Creator: Truex, Michael J.; Nimmons, Michael J.; Johnson, Christian D.; Dresel, P EVAN. & Murray, Christopher J.
Partner: UNT Libraries Government Documents Department

How Does Your Data Center Measure Up? Energy Efficiency Metrics and Benchmarks for Data Center Infrastructure Systems

Description: Data centers are among the most energy intensive types of facilities, and they are growing dramatically in terms of size and intensity [EPA 2007]. As a result, in the last few years there has been increasing interest from stakeholders - ranging from data center managers to policy makers - to improve the energy efficiency of data centers, and there are several industry and government organizations that have developed tools, guidelines, and training programs. There are many opportunities to reduce energy use in data centers and benchmarking studies reveal a wide range of efficiency practices. Data center operators may not be aware of how efficient their facility may be relative to their peers, even for the same levels of service. Benchmarking is an effective way to compare one facility to another, and also to track the performance of a given facility over time. Toward that end, this article presents the key metrics that facility managers can use to assess, track, and manage the efficiency of the infrastructure systems in data centers, and thereby identify potential efficiency actions. Most of the benchmarking data presented in this article are drawn from the data center benchmarking database at Lawrence Berkeley National Laboratory (LBNL). The database was developed from studies commissioned by the California Energy Commission, Pacific Gas and Electric Co., the U.S. Department of Energy and the New York State Energy Research and Development Authority.
Date: April 1, 2009
Creator: Mathew, Paul; Greenberg, Steve; Ganguly, Srirupa; Sartor, Dale & Tschudi, William
Partner: UNT Libraries Government Documents Department

Analysis of 2011 Meteorological Data from the Knolls Atomic Power Laboratory and Kesselring Site Operations Facilities

Description: Both the Knolls Atomic Power Laboratory (KAPL) in Schenectady, NY and the Kesselring Site Operations (KSO) facility near Ballston Spa, NY are required to estimate the effects of hypothetical emissions of radiological material from their respective facilities by the US Environmental Protection Agency (EPA), which regulates these facilities. An atmospheric dispersion model known as CAP88, which was developed and approved by the EPA for such purposes, is used by KAPL and KSO to meet this requirement. CAP88 calculations over a given time period are based on statistical data on the meteorological conditions for that period. Both KAPL and KSO have on-site meteorological towers which take atmospheric measurements at a frequency ideal for EPA regulatory model input. However, an independent analysis and processing of the meteorological data from each tower is required to derive a data set appropriate for use in the CAP88 model. The National Atmospheric Release Advisory Center (NARAC) was contracted by KAPL to process the on-site data for the calendar year 2011. The purpose of this document is to: (1) summarize the procedures used in the preparation/analysis of the 2011 meteorological data; and (2) document adherence of these procedures to the guidance set forth in 'Meteorological Monitoring Guidance for Regulatory Modeling Applications', EPA document - EPA-454/R-99-005 (EPA-454). This document outlines the steps in analyzing and processing meteorological data from the Knolls Atomic Power Laboratory and Kesselring Site Operations facilities into a format that is compatible with the steady state dispersion model CAP88. This process is based on guidance from the EPA regarding the preparation of meteorological data for use in regulatory dispersion models. The analysis steps outlined in this document can be easily adapted to process data sets covering time period other than one year. The procedures will need to be modified should the guidance in EPA-454 be ...
Date: February 27, 2012
Creator: Aluzzi, F J
Partner: UNT Libraries Government Documents Department

Memo to Skip Laitner of EPA: initial comments on 'The internetbegins with coal'

Description: This memo explores the assumptions in Mark P. Mills' report titled 'The Internet Begins with Coal' that relate to current electricity use 'associated with the Internet'. We find that Mills has significantly overestimated electricity use, in some cases by more than an order of magnitude. We adjust his estimates to reflect measured data and more accurate assumptions, which reduces Mills' overall estimate of total Internet-related electricity use by about a factor of eight.
Date: December 9, 1999
Creator: Koomey, Jonathan G.
Partner: UNT Libraries Government Documents Department

Surface water discharges from onshore stripper wells.

Description: Under current US Environmental Protection Agency (EPA) rules, small onshore oil producers are allowed to discharge produced water to surface waters with approval from state agencies; but small onshore gas producers, however, are prohibited from discharging produced water to surface waters. The purpose of this report is to identify those states that allow surface water discharges from small onshore oil operations and to summarize the types of permitting controls they use. It is intended that the findings of this report will serve as a rationale to encourage the EPA to revise its rules and to remove the prohibition on surface water discharges from small gas operations.
Date: January 16, 1998
Creator: Veil, J. A.
Partner: UNT Libraries Government Documents Department

K basins interim remedial action health and safety plan

Description: The K Basins Interim Remedial Action Health and Safety Plan addresses the requirements of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), as they apply to the CERCLA work that will take place at the K East and K West Basins. The provisions of this plan become effective on the date the US Environmental Protection Agency issues the Record of Decision for the K Basins Interim Remedial Action, currently planned in late August 1999.
Date: September 14, 1999
Creator: Day, P. T.
Partner: UNT Libraries Government Documents Department

Converting Limbo Lands to Energy-Generating Stations: Renewable Energy Technologies on Underused, Formerly Contaminated Sites

Description: This report addresses the potential for using 'Limbo Lands' (underused, formerly contaminated sites, landfills, brownfields, abandoned mine lands, etc. ) as sites for renewable energy generating stations.
Date: October 1, 2007
Creator: Mosey, G.; Heimiller, D.; Dahle, D.; Vimmerstedt, L. & Brady-Sabeff, L.
Partner: UNT Libraries Government Documents Department

Radionuclide Air Emission Report for 2007

Description: Berkeley Lab operates facilities where radionuclides are handled and stored. These facilities are subject to the U.S. Environmental Protection Agency (EPA) radioactive air emission regulations in Code of Federal Regulations (CFR) Title 40, Part 61, Subpart H (EPA 1989). The EPA regulates radionuclide emissions that may be released from stacks or vents on buildings where radionuclide production or use is authorized or that may be emitted as diffuse sources. In 2007, all Berkeley Lab sources were minor stack or building emissions sources of radionuclides (sources resulting in a potential dose of less than 0.1 mrem/yr [0.001 mSv/yr]), there were no diffuse emissions, and there were no unplanned emissions. Emissions from minor sources either were measured by sampling or monitoring or were calculated based on quantities received for use or produced during the year. Using measured and calculated emissions, and building-specific and common parameters, Laboratory personnel applied the EPA-approved computer code, CAP88-PC, Version 3.0, to calculate the effective dose equivalent to the maximally exposed individual (MEI). The effective dose equivalent from all sources at Berkeley Lab in 2007 is 1.2 x 10{sup -2} mrem/yr (1.2 x 10{sup -4} mSv/yr) to the MEI, well below the 10 mrem/yr (0.1 mSv/yr) EPA dose standard. The location of the MEI is at the University of California (UC) Lawrence Hall of Science, a public science museum about 1500 ft (460 m) east of Berkeley Lab's Building 56. The estimated collective effective dose equivalent to persons living within 50 mi (80 km) of Berkeley Lab is 3.1 x 10{sup -1} person-rem (3.1 x 10{sup -3} person-Sv) attributable to the Lab's airborne emissions in 2007.
Date: June 13, 2008
Creator: Wahl, Linnea & Wahl, Linnea
Partner: UNT Libraries Government Documents Department

Hydrogeology and tritium transport in Chicken Creek Canyon,Lawrence Berkeley National Laboratory, Berkeley, California

Description: This study of the hydrogeology of Chicken Creek Canyon wasconducted by the Environmental Restoration Program (ERP) at LawrenceBerkeley National Laboratory (LBNL). This canyon extends downhill fromBuilding 31 at LBNL to Centennial Road below. The leading edge of agroundwater tritium plume at LBNL is located at the top of the canyon.Tritium activities measured in this portion of the plume during thisstudy were approximately 3,000 picocuries/liter (pCi/L), which issignificantly less than the maximum contaminant level (MCL) for drinkingwaterof 20,000 pCi/L established by the Environmental ProtectionAgency.There are three main pathways for tritium migration beyond theLaboratory s boundary: air, surface water and groundwater flow. Thepurpose of this report is to evaluate the groundwater pathway.Hydrogeologic investigation commenced with review of historicalgeotechnical reports including 35 bore logs and 27 test pit/trench logsas well as existing ERP information from 9 bore logs. This was followedby field mapping of bedrock outcrops along Chicken Creek as well asbedrock exposures in road cuts on the north and east walls of the canyon.Water levels and tritium activities from 6 wells were also considered.Electrical-resistivity profiles and cone penetration test (CPT) data werecollected to investigate the extent of an interpreted alluvial sandencountered in one of the wells drilled in this area. Subsequent loggingof 7 additional borings indicated that this sand was actually anunusually well-sorted and typically deeply weathered sandstone of theOrinda Formation. Wells were installed in 6 of the new borings to allowwater level measurement and analysis of groundwater tritium activity. Aslug test and pumping tests were also performed in the wellfield.
Date: October 31, 2007
Creator: Jordan, Preston D. & Javandel, Iraj
Partner: UNT Libraries Government Documents Department

PROTECTING GROUNDWATER & THE COLUMBIA RIVER AT THE HANFORD SITE

Description: Along the remote shores of the Columbia River in southeast Washington state, a race is on. Fluor Hanford, a prime cleanup contractor to the U.S. Department of Energy (DOE) at the Hanford Site, is managing a massive, multi-faceted project to remove contaminants from the groundwater before they can reach the Columbia. Despite the daunting nature and size of the problem--about 80 square miles of aquifer under the site contains long-lived radionuclides and hazardous chemicals--significant progress is being made. Many groups are watching, speaking out, and helping. A large. passionate, diverse, and geographically dispersed community is united in its desire to protect the Columbia River--the eighth largest in the world--and have a voice in Hanford's future. Fluor Hanford and the DOE, along with the US. Environmental Protection Agency (EPA) and the Washington Department of Ecology (Ecology) interact with all the stakeholders to make the best decisions. Together, they have made some remarkable strides in the battle against groundwater contamination under the site.
Date: June 29, 2006
Creator: GERBER, M.S.
Partner: UNT Libraries Government Documents Department

INL SITEWIDE INSTITUTIONAL CONTROLS, AND OPERATIONS AND MAINTENANCE PLAN FOR CERCLA RESPONSE ACTIONS

Description: On November 9, 2002, the U.S. Environmental Protection Agency, the U.S. Department of Energy, and the Idaho Department of Environmental Quality approved the 'Record of Decision Experimental Breeder Reactor-I/Boiling Water Reactor Experiment Area and Miscellaneous Sites', which required a Site-wide institutional controls plan for the then Idaho National Engineering and Environmental Laboratory (now known as the Idaho National Laboratory). This document, first issued in June 2004, fulfilled that requirement. This revision identifies and consolidates the institutional controls and operations and maintenance requirements into a single document.
Date: February 5, 2008
Creator: Jolley, Wendell L.
Partner: UNT Libraries Government Documents Department

Validation and Comparison of Carbon Sequestration Project Cost Models with Project Cost Data Obtained from the Southwest Partnership

Description: Obtaining formal quotes and engineering conceptual designs for carbon dioxide (CO{sub 2}) sequestration sites and facilities is costly and time-consuming. Frequently, when looking at potential locations, managers, engineers and scientists are confronted with multiple options, but do not have the expertise or the information required to quickly obtain a general estimate of what the costs will be without employing an engineering firm. Several models for carbon compression, transport and/or injection have been published that are designed to aid in determining the cost of sequestration projects. A number of these models are used in this study, including models by J. Ogden, MIT's Carbon Capture and Sequestration Technologies Program Model, the Environmental Protection Agency and others. This report uses the information and data available from several projects either completed, in progress, or conceptualized by the Southwest Regional Carbon Sequestration Partnership on Carbon Sequestration (SWP) to determine the best approach to estimate a project's cost. The data presented highlights calculated versus actual costs. This data is compared to the results obtained by applying several models for each of the individual projects with actual cost. It also offers methods to systematically apply the models to future projects of a similar scale. Last, the cost risks associated with a project of this scope are discussed, along with ways that have been and could be used to mitigate these risks.
Date: April 15, 2011
Creator: Lee, Robert; Grigg, Reid & McPherson, Brian
Partner: UNT Libraries Government Documents Department

JV Task 86 - Identifying the Source of Benzene in Indoor Air Using Different Compound Classes from TO-15 Data

Description: Volatile organic compound (VOC) data that had already been collected using EPA method TO-15 at four different sites under regulatory scrutiny (a school, strip mall, apartment complex, and business/residential neighborhood) were evaluated to determine whether the source of indoor air benzene was outdoor air or vapor intrusion from contaminated soil. Both the use of tracer organics characteristic of different sources and principal component statistical analysis demonstrated that the source of indoor air at virtually all indoor sampling locations was a result of outdoor air, and not contaminated soil in and near the indoor air-sampling locations. These results show that proposed remediation activities to remove benzene-contaminated soil are highly unlikely to reduce indoor air benzene concentrations. A manuscript describing these results is presently being prepared for submission to a peer-reviewed journal.
Date: April 15, 2007
Creator: Hawthorne, Steven B.
Partner: UNT Libraries Government Documents Department

Underground Test Area Quality Assurance Project Plan Nevada National Security Site, Nevada, Revision 0

Description: This Quality Assurance Project Plan (QAPP) provides the overall quality assurance (QA) program requirements and general quality practices to be applied to the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) Underground Test Area (UGTA) Sub-Project (hereafter the Sub-Project) activities. The requirements in this QAPP are consistent with DOE Order 414.1C, Quality Assurance (DOE, 2005); U.S. Environmental Protection Agency (EPA) Guidance for Quality Assurance Project Plans for Modeling (EPA, 2002); and EPA Guidance on the Development, Evaluation, and Application of Environmental Models (EPA, 2009). The QAPP Revision 0 supersedes DOE--341, Underground Test Area Quality Assurance Project Plan, Nevada Test Site, Nevada, Revision 4.
Date: May 1, 2011
Creator: Farnham, Irene
Partner: UNT Libraries Government Documents Department

Explanation of Significant Differences for the Record of Decision for the Test Area North Operable Unit 1-10

Description: This Explanation of Significant Differences (ESD) applies to the remedial actions performed under the Final Record of Decision for Test Area North, Operable Unit 1-1 0, Idaho National Engineering and Environmental Laboratory (DOE-ID 1999) as amended by the Explanation of Significant Differences for the Record of Decision for the Test Area North Operable Unit 1-10 (DOE-ID 2003), the Record of Decision Amendment for the V-Tanks (TSF-09 and TSF-18) and Explanation of Significant Differences for the PM-2A Tanks (TSF-26) and TSF-06, Area IO, at Test Area North, Operable Unit 1-1 0 (DOE-ID 2004a), and the Explanation of Significant Differences for the Record of Decision for the Test Area North Operable Unit 1-10 (DOE-ID 2005). The U.S. Department of Energy (DOE) Idaho Operations Office; U.S. Environmental Protection Agency (EPA), Region 10; and the Idaho Department of Health and Welfare-now identified as the Idaho Department of Environmental Quality (DEQ)-signed the Record of Decision (ROD) in December 1999, the 2003 ESD in April 2003, the ROD Amendment/ESD in February 2004, and the 2005 ESD in January 2005. The EPA and DEQ support the need for this ESD.
Date: January 18, 2007
Creator: Eaton, D. L.
Partner: UNT Libraries Government Documents Department

Minimizing Reheat Energy Use in Laboratories

Description: HVAC systems that are designed without properly accounting for equipment load variation across laboratory spaces in a facility can significantly increase simultaneous heating and cooling, particularly for systems that use zone reheat for temperature control. This best practice guide describes the problem of simultaneous heating and cooling resulting from load variations, and presents several technological and design process strategies to minimize it. This guide is one in a series created by the Laboratories for the 21st century ('Labs21') program, a joint program of the U.S. Environmental Protection Agency and U.S. Department of Energy. Geared towards architects, engineers, and facilities managers, these guides provide information about technologies and practices to use in designing, constructing, and operating safe, sustainable, high-performance laboratories.
Date: November 29, 2005
Creator: Frenze, David; Mathew, Paul; Morehead, Michael; Sartor, Dale & Starr Jr., William
Partner: UNT Libraries Government Documents Department

Description of Spreadsheet Calculations for Populating Data Tables of the Ecological Risk Assessment (Appendix B of the Human Health and Ecological Risk Assessment Document) for the Explosives Waste Treatment Facility (EWTF) at Site 300

Description: This ecological risk assessment (ERA) is a supplement to the human health risk assessment (HRA) for the Explosive Waste Treatment Facility (EWTF). The EWTF is located near the center of Site 300 in a small, isolated canyon (see Figures 2 through 6 in the text). The ERA described in detail in Appendix B was prepared in accordance with guidance on currently accepted practice provided by the Human and Ecological Risk Division (HERD) at the Department of Toxic Substances Control (DSTC) of the State of California Environmental Protection Agency (CalEPA) in Sacramento, California. The technical basis for this ERA is an analysis that involves a series of screening calculations to assess each of 21 contaminants of potential ecological concern (CPECs) for its potential to produce an adverse ecological impact in particular wildlife species, including vegetation, considered representative receptors of ecological interest (RREI) in the trophic levels of the food network at Site 300. This series of screening calculations is designed to illustrate whether CPECs identified as being of possible consequence in the most conservative screening calculation actually may be of lesser or no significance when more information is considered in subsequent screening calculations.
Date: October 1, 2007
Creator: Daniels, J
Partner: UNT Libraries Government Documents Department

Radionuclide Air Emission Report for 2008

Description: Berkeley Lab operates facilities where radionuclides are handled and stored. These facilities are subject to the U.S. Environmental Protection Agency (EPA) radioactive air emission regulations in Code of Federal Regulations (CFR) Title 40, Part 61, Subpart H (EPA 1989). Radionuclides may be emitted from stacks or vents on buildings where radionuclide production or use is authorized or they may be emitted as diffuse sources. In 2008, all Berkeley Lab sources were minor sources of radionuclides (sources resulting in a potential dose of less than 0.1 mrem/yr [0.001 mSv/yr]). These minor sources include more than 100 stack sources and one source of diffuse emissions. There were no unplanned emissions from the Berkeley Lab site. Emissions from minor sources (stacks and diffuse emissions) either were measured by sampling or monitoring or were calculated based on quantities used, received for use, or produced during the year. Using measured and calculated emissions, and building-specific and common parameters, Laboratory personnel applied the EPA-approved computer code, CAP88-PC, to calculate the effective dose equivalent to the maximally exposed individual (MEI). The effective dose equivalent from all sources at Berkeley Lab in 2008 is 5.2 x 10{sup -3} mrem/yr (5.2 x 10{sup -5} mSv/yr) to the MEI, well below the 10 mrem/yr (0.1 mSv/yr) dose standard. The location of the MEI is at the University of California (UC) Lawrence Hall of Science, a public science museum about 1500 ft (460 m) east of Berkeley Lab's Building 56. The estimated collective effective dose equivalent to persons living within 50 mi (80 km) of Berkeley Lab is 1.1 x 10{sup -1} person-rem (1.1 x 10{sup -3} person-Sv) attributable to the Lab's airborne emissions in 2008.
Date: May 21, 2009
Creator: Wahl, Linnea
Partner: UNT Libraries Government Documents Department

Screening of Potential Remediation Methods for the 200-BP-5 Operable Unit at the Hanford Site

Description: A screening-level evaluation of potential remediation methods for application to the contaminants of concern (COC) in the 200-BP-5 Operable Unit at the Hanford Site was conducted based on the methods outlined in the Guidance for Conducting Remedial Investigations and Feasibility Studies under CERCLA Interim Final (EPA 1988). The scope of this screening was to identify the most promising remediation methods for use in the more detailed analysis of remediation alternatives that will be conducted as part of the full feasibility study. The screening evaluation was conducted for the primary COC (potential major risk drivers) identified in the groundwater sampling and analysis plan for the operable unit (DOE/RL-2001-49, Rev. 1) with additions.
Date: September 21, 2006
Creator: Truex, Michael J.; Dresel, P. EVAN; Nimmons, Michael J. & Johnson, Christian D.
Partner: UNT Libraries Government Documents Department

Rapid Estimation of TPH Reduction in Oil-Contaminated Soils Using the MED Method

Description: Oil-contaminated soil and sludge generated during federal well plugging activities in northwestern Pennsylvania are currently remediated on small landfarm sites in lieu of more expensive landfill disposal. Bioremediation success at these sites in the past has been gauged by the decrease in total petroleum hydrocarbon (TPH) concentrations to less than 10,000 mg/kg measured using EPA Method 418.1. We tested the “molarity of ethanol droplet” (MED) water repellency test as a rapid indicator of TPH concentration in soil at one landfarm near Bradford, PA. MED was estimated by determining the minimum ethanol concentration (0 – 6 M) required to penetrate air-dried and sieved soil samples within 10 sec. TPH in soil was analyzed by rapid fluorometric analysis of methanol soil extracts, which correlated well with EPA Method 1664. Uncontaminated landfarm site soil amended with increasing concentrations of waste oil sludge showed a high correlation between MED and TPH. MED values exceeded the upper limit of 6 M as TPH estimates exceed ca. 25,000 mg/kg. MED and TPH at the land farm were sampled monthly during summer months over two years in a grid pattern that allowed spatial comparisons of site remediation effectiveness. MED and TPH decreased at a constant rate over time and remained highly correlated. Inexpensive alternatives to reagent-grade ethanol gave comparable results. The simple MED approach served as an inexpensive alternative to the routine laboratory analysis of TPH during the monitoring of oily waste bioremediation at this landfarm site.
Date: September 1, 2007
Creator: Edenborn, H. M. & Zenone, V. A.
Partner: UNT Libraries Government Documents Department

Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

Description: Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.
Date: September 10, 2003
Creator: Leggett, R.W.
Partner: UNT Libraries Government Documents Department

2010 Groundwater Monitoring and Inspection Report Gnome-Coach Site, New Mexico

Description: This report presents the 2010 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Gnome-Coach (Gnome) Site in New Mexico (Figure 1). Groundwater monitoring consisted of collecting hydraulic head data and groundwater samples from the wells on site. Historically, the U.S. Environmental Protection Agency (EPA) had conducted these annual activities under the Long-Term Hydrologic Monitoring Program (LTHMP). LM took over the sampling and data collection activities in 2008 but continues to use the EPA Radiation and Indoor Environments National Laboratory in Las Vegas, Nevada, to analyze the water samples. This report summarizes groundwater monitoring and site investigation activities that were conducted at the site during calendar year 2010.
Date: February 1, 2011
Partner: UNT Libraries Government Documents Department

THE SCENARIOS APPROACH TO ATTENUATION-BASED REMEDIES FOR INORGANIC AND RADIONUCLIDE CONTAMINANTS

Description: Guidance materials based on use of conceptual model scenarios were developed to assist evaluation and implementation of attenuation-based remedies for groundwater and vadose zones contaminated with inorganic and radionuclide contaminants. The Scenarios approach is intended to complement the comprehensive information provided in the US EPA's Technical Protocol for Monitored Natural Attenuation (MNA) of Inorganic Contaminants by providing additional information on site conceptual models and extending the evaluation to consideration of Enhanced Attenuation approaches. The conceptual models incorporate the notion of reactive facies, defined as units with hydrogeochemical properties that are different from surrounding units and that react with contaminants in distinct ways. The conceptual models also incorporate consideration of biogeochemical gradients, defined as boundaries between different geochemical conditions that have been induced by waste disposal or other natural phenomena. Gradients can change over time when geochemical conditions from one area migrate into another, potentially affecting contaminant mobility. A recognition of gradients allows the attenuation-affecting conditions of a site to be projected into the future. The Scenarios approach provides a stepwise process to identify an appropriate category of conceptual model and refine it for a specific site. Scenario materials provide links to pertinent sections in the EPA technical protocol and present information about contaminant mobility and important controlling mechanism for attenuation-based remedies based on the categories of conceptual models.
Date: August 4, 2011
Creator: Vangelas, K.; Rysz, M.; Truex, M.; Brady, P.; Newell, C. & Denham, M.
Partner: UNT Libraries Government Documents Department