The Hydrogeologic effects of fly ash utilization in concrete at Coal Creek Station, Underwood, North Dakota

Coal Creek Station is a two-unit 1100 megawatt electrical power plant located in southern McLean county, North Dakota. Annually, 5 million tons (4.5 million metric tons) of lignite are burned at the plant producing 550,000 tons (500,000 metric tons) of fly ash. Approximately 80,000 tons (72,624 metric tons) of ash are sold as a cement replacement, while the remainder is disposed of in lined evaporation ponds. The present study investigates the environmental consequences of ash utilization as an alternative to disposal, The Electric Power Research Institute (EPRI) provided funding for this investigation which involves the installation of 5,288 cu yds (4,043 m3) of concrete in roadways at ccs. The concrete contains a 70% replacement of Portland cement with fly ash. The purpose of this study was to determine whether or not use of fly ash in concrete releases any environmentally deleterious substances to soil or ground water. Stratigraphy at the site consists of a variable unit of fill material underlain by Paleocene bedrock of the Sentinel Butte Formation. The fill unit was created by construction projects during the past 10 years. Fill materials are more permeable than bedrock, consequently the occurrence of fill influences recharge rates and ground water flow patterns. A comprehensive water monitoring network encompassing surface water, unsaturated zone water, and saturated zone water was designed for the site. Surface water quality was documented using a runoff collector and precipitation collector. soil moisture and ground water occurrence and quality were monitored using pressure-vacuum lysimeters and monitoring wells. Two geologically distinct sites were instrumented, one representing a recharge zone {monitoring nest 2) and the other a zone of little recharge (monitoring nest 1). Each monitoring nest contains J pressure vacuum lysimeters at depths of 5, 10, and 15 feet (1.5, J.o, and 4.5 m) and 1 monitoring well. Both monitoring nests were downgradient of fly ash concrete installations. Background water quality data were provided by preconstruction samples and two monitoring wells upgradient from the site. To date, data suggest that there has been no degradation in water quality attributable to leaching from the concrete. Data obtained from monitoring nest 2 indicate that in recharge zones the composition of water in the saturated zone is largely determined within the unsaturated zone. The creation of localized recharge zones may mobilize certain constituents of the unsaturated zone causing a degradation of water quality in the saturated zone. In settings characterized by low recharge, much of the mineralization available to the system remains in the unsaturated zone and the composition of the unsaturated and saturated zone remains chemically distinct

A QUALITATIVE CHOICE ANALYSIS OF FACTORS INFLUENCING POST-CRP LAND USE DECISIONS

The future use of Conservation Reserve Program (CRP) lands is an important agricultural policy issue. To examine the effects of factors that influence landowners' post-contract use of CRP lands, a survey of Texas High Plains CRP contract holders was conducted in 1992. This study analyzes the results of the survey using a qualitative choice model. It was found that the presence of a livestock enterprise in the current contract holder's operation increases the probability of these acres remaining in the established cover. Contract holders who value the commodity base have an increased probability of returning their acres to crop production.Agricultural policy, Conservation Reserve Program, Ordered probit model, Land Economics/Use,

Evaluating the Business Impact of Social Science: a report to the ESRC

This report presents the main findings from a project entitled ‘Evaluating the Business Impact of Social Science', commissioned by the Economic and Social Research Council (ESRC) and undertaken by a team of researchers from the University of Hull. In brief, the project involved an examination of the processes through which social science research and related activities impact upon business (defined broadly to incorporate large and small private sector businesses as well as social enterprises, but excluding public sector organisations) in relation to three of the UK’s leading business/management schools that have received significant amounts of ESRC funding in recent years: Cardiff Business School, Lancaster University Management School, and Warwick Business Schoo

Public health advocacy in action: the case of unproven breast cancer screening in Australia

In recent years, nonmammographic breast imaging devices, such as thermography, electrical impedance scanning and elastography, have been promoted directly to consumers, which has captured the attention of governments, researchers and health organisations. These devices are not supported by evidence and risk undermining existing mammographic breast cancer screening services. During a 5-year period, Cancer Council Western Australia (CCWA) used strategic research combined with legal, policy and media advocacy to contest claims that these devices were proven alternatives to mammography for breast cancer screening. The campaign was successful because it had input from people with public health, academic, clinical and legal backgrounds, and took advantage of existing legal and regulatory avenues. CCWA's experience provides a useful advocacy model for public health practitioners who are concerned about unsafe consumer products, unproven medical devices, and misleading health information and advertising

Survey of sediment quality in Sabine Lake, Texas and vicinity

The toxicity of sediments in Sabine Lake, Texas, and adjoining Intracoastal Waterway canals was determined as part of bioeffects assessment studies managed by NOAA’s National Status and Trends Program. The objectives of the survey were to determine: (1) the incidence and degree of toxicity of sediments throughout the study area; (2) the spatial patterns (or gradients) in chemical contamination and toxicity, if any, throughout the study area; (3) the spatial extent of chemical contamination and toxicity; and (4) the statistical relationships between measures of toxicity and concentrations of chemicals in the sediments. Surficial sediment samples were collected during August, 1995 from 66 randomly-chosen locations. Laboratory toxicity tests were performed as indicators of potential ecotoxicological effects in sediments. A battery of tests was performed to generate information from different phases (components) of the sediments. Tests were selected to represent a range in toxicological endpoints from acute to chronic sublethal responses. Toxicological tests were conducted to measure: reduced survival of adult amphipods exposed to solid-phase sediments; impaired fertilization success and abnormal morphological development in gametes and embryos, respectively, of sea urchins exposed to pore waters; reduced metabolic activity of a marine bioluminescent bacteria exposed to organic solvent extracts; and induction of a cytochrome P-450 reporter gene system in exposures to solvent extracts of the sediments. Chemical analyses were performed on portions of each sample to quantify the concentrations of trace metals, polynuclear aromatic hydrocarbons, and chlorinated organic compounds. Correlation analyses were conducted to determine the relationships between measures of toxicity and concentrations of potentially toxic substances in the samples. Based upon the compilation of results from chemical analyses and toxicity tests, the quality of sediments in Sabine Lake and vicinity did not appear to be severely degraded. Chemical concentrations rarely exceeded effects-based numerical guidelines, suggesting that toxicant-induced effects would not be expected in most areas. None of the samples was highly toxic in acute amphipod survival tests and a minority (23%) of samples were highly toxic in sublethal urchin fertilization tests. Although toxic responses occurred frequently (94% of samples) in urchin embryo development tests performed with 100% pore waters, toxicity diminished markedly in tests done with diluted pore waters. Microbial bioluminescent activity was not reduced to a great degree (no EC50 <0.06 mg/ml) and cytochrome P-450 activity was not highly induced (6 samples exceeded 37.1 ug/g benzo[a]pyrene equivalents) in tests done with organic solvent extracts. Urchin embryological development was highly correlated with concentrations of ammonia and many trace metals. Cytochrome P450 induction was highly correlated with concentrations of a number of classes of organic compounds (including the polynuclear aromatic hydrocarbons and chlorinated compounds). (PDF contains 51 pages

Performance of three- and five-stack achromatic half-wave plates at millimeter wavelengths

We study the performance of achromatic half-wave plates (AHWPs) as a function of the detection bandwidth of a power detector operating in the millimeter wave band and the spectral shape of the incident radiation. We focus particular attention on the extraction of the degree of incident polarization and its orientation angle from the intensity measured as a function of AHWP rotation angle, which we call the IVA (intensity versus angle). We describe the formalism to extract the two incident polarization parameters. We use this formalism to quantify the phase offset of the IVA and point to potential systematic errors in the extraction of this offset in cases where the incident spectrum is not sufficiently well known. We quantify the phase offset and modulation efficiency as a function of the relative angles between the plates in the stack and find that high modulation efficiency can be achieved with alignment accuracy of a few degrees. We present measurements of the spectral response of an AHWP made with five plates. The measurements predict a modulation efficiency that is higher than 98% for three bands centered at 150, 250, and 410 GHz

Predicting participation in group parenting education in an Australian sample: The role of attitudes, norms, and control factors

We examined the theory of planned behavior (TPB) in predicting intentions to participate in group parenting education. One hundred and seventy-six parents (138 mothers and 38 fathers) with a child under 12 years completed TPB items assessing attitude, subjective norms, perceived behavioral control (PBC), and two additional social influence variables (self-identity and group norm). Regression analyses supported the TPB predictors of participation intentions with self-identity and group norm also significantly predicting intentions. These findings offer preliminary support for the TPB, along with additional sources of social influence, as a useful predictive model of participation in parenting education