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[en] This report provides the results of the annual post-closure inspections conducted at the closed Corrective Action Units (CAUs) located on the Tonopah Test Range (TTR), Nevada. This report covers calendar year 2010 and includes inspection and repair activities completed at the following seven CAUs: (1) CAU 400: Bomblet Pit and Five Points Landfill (TTR); (2) CAU 407: Roller Coaster RadSafe Area (TTR); (3) CAU 424: Area 3 Landfill Complexes (TTR); (4) CAU 426: Cactus Spring Waste Trenches (TTR); (5) CAU 453: Area 9 UXO Landfill (TTR); (6) CAU 484: Surface Debris, Waste Sites, and Burn Area (TTR); and (7) CAU 487: Thunderwell Site (TTR).
[en] This study was designed to accomplish two objectives. The first was to provide to the US Air Force and the regulatory community quantitative procedures that they might want to consider using for addressing uncertainty and variability in exposure to better characterize potential health risk. Such methods could be used at sites where populations may now or in the future be faced with using groundwater contaminated with low concentrations of the chemical trichloroethylene (TCE). The second was to illustrate and explain the application of these procedures with respect to available data for TCE in ground water beneath an inactive landfill site that is undergoing remediation at Beale Air Force Base in California. The results from this illustration provide more detail than the more traditional conservative deterministic, screening-level calculations of risk, also computed for purposes of comparison. Application of the procedures described in this report can lead to more reasonable and equitable risk-acceptability criteria for potentially exposed populations at specific sites
[en] Traditional estimates of health risk are typically inflated, particularly if cancer is the dominant endpoint and there is fundamental uncertainty as to mechanism(s) of action. Risk is more realistically characterized if it accounts for joint uncertainty and interindividual variability after applying a unified probabilistic approach to the distributed parameters of all (linear as well as nonlinear) risk-extrapolation models involved. Such an approach was applied to characterize risks to potential future residents posed by trichloroethylene (TCE) in ground water at an inactive landfill site on Beale Air Force Base in California. Variability and uncertainty were addressed in exposure-route-specific estimates of applied dose, in pharmacokinetically based estimates of route-specific metabolized fractions of absorbed TCE, and in corresponding biologically effective doses estimated under a genotoxic/linear (MA(sub g)) vs. a cytotoxic/nonlinear (MA(sub c)) mechanistic assumption for TCE-induced cancer. Increased risk conditional on effective dose was estimated under MA(sub G) based on seven rodent-bioassay data sets, and under MA, based on mouse hepatotoxicity data. Mean and upper-bound estimates of combined risk calculated by the unified approach were and lt;10(sup -6) and and lt;10(sup -4), respectively, while corresponding estimates based on traditional deterministic methods were and gt;10(sup -5) and and gt;10(sup -4), respectively. It was estimated that no TCE-related harm is likely occur due any plausible residential exposure scenario involving the site. The unified approach illustrated is particularly suited to characterizing risks that involve uncertain and/or diverse mechanisms of action
[en] This report provides the results of the annual post-closure inspections conducted at the closed Corrective Action Unit (CAU) sites located on the Tonopah Test Range (TTR), Nevada. This report covers calendar year 2008 and includes inspection and repair activities completed at the following ten CAUs: CAU 400: Bomblet Pit and Five Points Landfill (TTR) CAU 404: Roller Coaster Lagoons and Trench (TTR) CAU 407: Roller Coaster RadSafe Area (TTR) CAU 423: Area 3 Underground Discharge Point, Building 0360 (TTR) CAU 424: Area 3 Landfill Complexes (TTR) CAU 426: Cactus Spring Waste Trenches (TTR) CAU 427: Area 3 Septic Waste Systems 2, 6 (TTR) CAU 453: Area 9 UXO Landfill (TTR) CAU 484: Surface Debris, Waste Sites, and Burn Area (TTR) CAU 487: Thunderwell Site (TTR)
[en] The landfilling of organic waste will be prohibited in Sweden from 1 January 2005. Ash containing unburnt material in the form of organic carbon may be covered by the ban. This report provides a technical basis for the Swedish Environmental Protection Agency in its work on drawing up regulations relating to exemptions from the ban on landfilling organic waste. Approximately one million tonnes of ash a year are produced in Sweden, of which 500,000 to 700,000 tonnes are sent to landfill. This ash contains varying levels of unburnt material. The unburnt material consists of carbon in three different forms: organic, elemental and inorganic carbon. It is the organic carbon that causes an adverse environmental impact in landfills. On the other hand, there is a European standard for the determination of TOC (total organic carbon) in waste which gives the sum of organic and elemental carbon. The content of unburnt material or loss on ignition varies within wide limits, due firstly to different measuring methods and secondly to the design and operating conditions of the incineration plant. The proportion of unburnt carbon is often low in ash from CFB boilers, somewhat higher in ash from BFB boilers and often relatively high in ash from grate boilers and boilers based on powder burners. It is technically possible to reburn ash that has a high level of unburnt material. This may, however, lead to technical problems such as corrosion in the boiler, and reburning does not always result in a sufficiently low level of unburnt material
[en] In the first quarter of calendar year 2017, a salt solution sample was collected from Tank 50 on January 16, 2017 in order to meet South Carolina (SC) Regulation 61-107.19 Part I C, ''Solid Waste Management: Solid Waste Landfills and Structural Fill - General Requirements'' and the Saltstone Disposal Facility Class 3 Landfill Permit. The Savannah River National Laboratory (SRNL) was requested to prepare and ship saltstone samples to a United States Environmental Protection Agency (EPA) certified laboratory to perform the Toxicity Characteristic Leaching Procedure (TCLP) and subsequent characterization.
[en] The Subsurface Disposal Area is a radioactive waste landfill located within the Radioactive Waste Management Complex at the Idaho National Laboratory Site in southeastern Idaho. This Feasibility Study for Operable Unit 7-13/14 analyzes options for mitigating risks to human health and the environment associated with the landfill. Analysis is conducted in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act, using nine evaluation criteria to develop detailed and comparative analysis of five assembled alternatives. Assembled alternatives are composed of discrete modules. Ultimately, decision-makers will select, recombine, and sum various modules into an optimized preferred alternative and final remedial decision