Abstract : A conceptual level development of the use of composting technology for the treatment of explosives-contaminated lagoon sediments has been conducted. Previous investigations of the technical aspects of explosives composting, including recent USATHAMA field demonstrations have indicated that composting can significatly reduce explosives contaminant levels. Conceptual level facility design, construction and operating requirements for implementation of composting have been developed based on the current level of knowledge with respect to the technical and regulatory aspects of the process. The economics of the process has been evaluated to include the economic sensitivity of the process to various design and operating variables. This evaluation is based on the areated static pile method. It does not include mechanical or in-vessel composting since they have not been tested with explosive-contaminated soil. Based upon present field demonstration data, implementation of composting for explosive-contaminated soil would likely prove to be expensive. However, further evaluation of compost mixture soil ratio, amendment costs, process kinetics, and performance criteria result in significant economic improvements.
Abstract : The patented Low Temperature Thermal Treatment (LT3) System was previously proven to be successful in treating soils contaminated with volatile organic compounds and petroleum hydrocarbons. This demonstration broadened the applicability to include soils contaminated with aviation fuel and other halogenated solvents. Several test were conducted to verify the effectiveness of the LT3 system. While meeting all goal cleanup objectives, a processing rate of 20,000 lb/hr was demonstrated with a projected LT3 System processing cost of $86/ton. A number of system changes and process improvements are recommended. The system proved to be an efficient, cost-effective, and commercially available remediation alternative for decontaminating soils. Keywords: Volatile organic compounds, Fuel, Thermal treatment, Trichloroethene, Low temperature thermal treatment.
Abstract : This report describes findings of an in situ pilot-scale air stripping study for treatment of volatile organic compounds (VOC) contaminated soils. In situ air stripping involves the removal of volatile organics from the soil matrix by mechanically drawing or venting air through the unsaturated contaminated soil layer. The pilot study was conducted during a 14-week field program from 19 November 1984 through 23 February 1985 at the Twin Cities Army Ammunition Plant (TCAAP), located in New Brighton, Minnesota. The in situ air stripping pilot study had two objectives. The primary objective of the pilot study was to determine the feasibility of applying in situ air stripping as a remedial action for removing TCE and other VOC's from a soil matrix. Although air stripping techniques have been applied for the removal of chlorinated organics and light molecular weight hydrocarbons from contaminated soils at other sites, the overall effectiveness, as well as system design and operating parameters, had not been previously established. Secondary objectives of this pilot study included the following: (a) Investigation of design parameters impacting the effectiveness of technology, including air flow rate and spacing requirements for air injection and extraction vent pipes, (b) Determination of removal effectiveness and removal rates compared to soil moisture, temperature, and initial VOC concentrations, (c) Preparation of conceptual engineering cost estimates (order-of-magnitude) for application of this technology, and (d) Identification of any future research for system optimization.
Abstract : The United States Army operates explosives manufacturing plants to produce various forms of explosives used in military ordnance. Manufacturing activities at such plants result in the production of organic wastewaters that contain both explosive residues and other organic chemicals. Several treatment technologies have been developed to treat these wastewaters for final discharge. Past waste handling practices at explosives manufacturing plants commonly included the use of the unlined lagoons or pits for containing process wastewaters. As a result of these past practices, some explosives residues may leach through the soil and contaminated groundwater. Therefore, the treatment of contaminated groundwater may be required.
Abstract : The primary objective of this task was to determine the feasibility of using GAC to treat ground water contaminated by explosives at the Milan Army Ammunition Plant (MAAP) in Milan, Tennessee. Laboratory GAC isotherm studies were conducted and two carbons, Atochem, Inc. GAC 830 and Calgon Filtrasorb 300, were selected for further testing in continuous flow GAC columns. Three pilot scale continuous flow GAC column tests were performed at MAAP using the two carbons selected from the laboratory GAC isotherm studies. The results from the laboratory and pilot studies are presented in this report. They show that concurrent removal of explosives such as TNT, RDX, HMX, Tetryl, and nitrobenzenes from ground water using continuous flow granular activated carbon is feasible.
Abstract : A field-scale demonstration of composting propellants-contaminated sediment was conducted at the Badger Army Ammunition Plant (BAAP). Composting, as used at BAAP, is a treatment process in which organic-chemical contaminated soils or sediments are mixed with organic materials such as manure to enhance the role of microbial metabolism in degrading and stabilizing soil/sediment contaminants. Sediments contaminated with the propellant nitrocellulose (NC) were mixed with manure, alfalfa, livestock feed, and wood chips and composted in four static piles. Negative pressure aeration was used to maintain aerobiosis and remove excess heat. Experimental variables investigated during the study were temperature (mesophilic, 35 C vs. thermophilic, 55 C), sediment loading (19 to 32 weight percent), and NC loading. Small aliquots of compost (approximately 400 cu cm) were spiked with pure NC, placed in porous nylon bags and buried in compost piles. These bagged compost samples were used to determine if high levels of NC could be successfully composted. Thermophilic temperatures resulted in the highest percent reduction in NC concentration.
This guide is intended to be used to screen and evaluate candidate cleanup technologies for contaminated installations and waste sites in order to assist remedial project managers (RPMs) in selecting a remedial alternative. The guide allows the reader to gather essential descriptive information on the respective treatment technologies. It incorporates cost and performance data to the maximum extent available and focuses primarily on demonstrated technologies; however, emerging technologies may be more appropriate in some cases, based upon site conditions and requirement. These technologies are applicable at all types of site cleanups: Superfund, DOD, DOE, RCRA, state, private, etc.
The aim of the study was to determine the effect of deprivation on variations in statin prescribing in Nottingham general practices. Deprivation is used as a measure of population cardiovascular morbidity and need for statin treatment. The setting was all 118 general practices in contract with Nottingham Health Authority.A cross-sectional study was undertaken. Statin prescribing in general practice during 1996 was related to indices of practice deprivation based on enumeration district (ED) level data from the 1991 Census. The relationship between statin prescribing per 1000 patients aged 35-69 and practice deprivation (measured both as Townsend score and as Jarman UPA(8) score) with additional adjustment for practice characteristics (number of partners, training status, total list size, fundholding status) cardiovascular prescribing costs net of lipid prescribing and hospital activity (total and medical admissions and new general practitioner total and medical out-patient referrals) for each practice.The prescription of statins during 1996 varied between nil and 14.1 'statin-years' of prescribing per 1000 patients aged 35-69. There was a significant inverse relationship between the rate of statin prescribing and the level of deprivation of that practice (p < 0.0001). Deprivation, as measured by Townsend index, accounted for 13 per cent of the total variability in statin prescribing, which rose to 19 per cent after adjustment. The prescribing of other lipid lowering agents of the fibrate class was positively associated with statin prescribing (p=0.001) and this association persisted after adjusting for deprivation. None of the other practice characteristics were found to be significantly associated with rates of statin prescribing.General practices with high deprivation indices serve more deprived populations with a higher prevalence of cardiovascular disease, and may be assumed to have a greater need for statins. Despite this, practices with higher deprivation indices prescribed fewer statins to their patients than less deprived practices. It was not possible to identify whether the more deprived general practices had successfully identified at risk individuals but it is likely that special efforts are needed to increase the uptake of effective health care in their patients.
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)
