Policies for the Planning and Reclamation of Coal-mined Landscapes: An International Comparison

Governments differ significantly in their attempts to mitigate the effects of mining disturbance. The approaches of Australia, Canada and the United States are reviewed here, relative to coal-mining reclamation. State and provincial examples (Queensland, Alberta and Montana) are used to illustrate legislation and planning below the national level. This paper explores three main issues that contribute to coal-mining reclamation: governmental level of legislation and planning; legislative scope; and inter-governmental co-ordination. The legislative histories vary, but are young and evolving. All require the submission of a reclamation plan before granting mining permits, enforce reclamation standards by security deposits and contain provisions for non-compliance. Australia and Canada are only beginning to address reclamation planning at the national level, whereas the United States has done so since 1977. The relationship to the environmental impact assessment process is uneven across the three nations. The United States and Canada have a larger percentage of their mined landscapes in a reclamation process, due partly to more stringent regulation. Reclamation effectiveness seems to centre less on centralization versus decentralization, and more on comprehensive scope, preventive approaches and multi-level governmental co-ordination.     

Environmental Awareness, Economic Orientation, and Farming Practices: A Comparison of Organic and Conventional Farmers

/ This study examines similarities and differences between organic and conventional farmers. We explore the factors that underlie farmers' conservation attitudes and behaviors, including demographic and farm characteristics, awareness of and concern for environmental problems associated with agriculture, economic orientation toward farming, and self-reported conservation practices. A series of intensive personal interviews was conducted with 25 farmers in Washtenaw County, Michigan, USA, using both qualitative and quantitative survey methods. The findings indicate that both groups of farmers share a concern for the economic risks associated with farming, although the organic farmers reported a significantly greater concern for long-term sustainability and a greater willingness to incur present risk to gain future benefits. Organic farmers expressed a greater awareness of and concern for environmental problems associated with agriculture. Organic farmers also scored significantly higher on a multifaceted measure of conservation practices, although both groups had a fairly high adoption rate. Implications of these findings are discussed, relative to economic risks of farming, implications for new farmers, effectiveness of conservation education and government programs, and impact of farm size and crop diversity.KEY WORDS: Environmental attitudes; Conservation behaviors; Organic farming; Agricultural sustainability     

Injuries causing death: Their nature,external causes,and associated diseases

This article provides national data on the types of injuries reported on death certificates, the external causes of these injuries, and diseases that are frequently reported with them. Injuries were a factor in 11 % (213,366 deaths) of the deaths to residents of the United States in 1978. Of 11 broad categories of injuries, three (fractures, sprains, strains, and dislocations, intracranial injuries, and adverse effects) were mentioned on almost 50,000 deaths each. There was considerable variation in the distribution of injury types by age, sex, and race. The most notable example was fractures of the lower limb which were mentioned on 29% of the deaths involving an injury to 65 + year olds but no less than 5% of such deaths for all other age groups. For white females, the percentage with a fracture of the lower limb was 23 % compared to 12 % overall. In 25 % of the deaths involving an injury, the immediate cause was a motor vehicle accident. In 51 %, the immediate cause of the injury was a non-motor-vehicle accident. In 73 % of the deaths involving non-motor-vehicle accidents, disease conditions as well as injuries were a factor; and, 69% of the time, the disease condition was actually the underlying cause of the death with the injury being a contributing factor or complication. For example, over 14,000 deaths in 1978 involved a circulatory condition as the underlying cause of death which was complicated by an accidental fracture, sprain, or dislocation. Although diseases more often assumed the role of the underlying cause of death, they were also a nonunderlying cause in 24,000 non-motor-vehicle accident deaths. Over 12,000 of such deaths involved circulatory diseases.     

Outdoor/Indoor/Personal ozone exposures of children in Nashville, Tennessee

An ozone (O3) exposure study was conducted in Nashville, TN, using passive O3 samplers to measure six weekly outdoor, indoor, and personal O3 exposure estimates for a group of 10- to 12-yr-old elementary school children. Thirty-six children from two Nashville area communities (Inglewood and Hendersonville) participated in the O3 sampling program, and 99 children provided additional time-activity information by telephone interview. By design, this study coincided with the 1994 Nashville/Middle Tennessee Ozone Study conducted by the Southern Oxidants Study, which provided enhanced continuous ambient O3 monitoring across the Nashville area. Passive sampling estimated weekly average outdoor O3 concentrations from 0.011 to 0.O30 ppm in the urban Inglewood community and from 0.015 to 0.042 ppm in suburban Hendersonville. The maximum 1- and 8-hr ambient concentrations encountered at the Hendersonville continuous monitor exceeded the levels of the 1- and 8-hr metrics for the O3 National Ambient Air Quality Standard. Weekly average personal O3 exposures ranged from 0.0013 to 0.0064 ppm (7-31% of outdoor levels). Personal O3 exposures reflected the proportional amount of time spent in indoor and outdoor environments. Air-conditioned homes displayed very low indoor O3 concentrations, and homes using open windows and fans for ventilation displayed much higher concentrations.     

A field study of triclosan loss rates in river water (Cibolo Creek, TX)

Triclosan (TCS) is an anti-microbial agent used in down-the-drain consumer products. Following sewage treatment some of the triclosan will enter receiving waters. This study was designed to determine the die-away rate of triclosan released into a river as part of the sewage treatment plant effluent matrix. The study was conducted in Cibolo Creek, a moderate sized stream (discharge approximately 0.1 m(3)s(-1)) located in South Central Texas. Triclosan was analyzed from samples collected upstream of the sewage treatment plant, the sewage treatment plant effluent, and the river downstream from the effluent discharge. The first-order loss rate of parent triclosan from the water column was calculated from measured data (0.06 h(-1)) and this rate corresponded to a 76% reduction in triclosan over an 8 km river reach below the discharge. Mathematical modeling indicated that sorption and settling accounted for approximately 19% of total triclosan loss over 8 km. When removing sorption and settling, the remaining amount of triclosan had an estimated first-order loss rate of 0.25 h(-1). This loss rate was presumably due to other processes such as biodegradation and photolysis. These data show that loss of parent triclosan from the water column is rapid. Additional data are needed to fully document loss mechanisms.     

Multi-element accumulation near Rumex crispus roots under wetland and dryland conditions

Rumex crispus was grown under wet and dry conditions in two-chamber columns such that the roots were confined to one chamber by a 21 μm nylon mesh, thus creating a soil-root interface (‘rhizoplane’). Element concentrations at 3 mm intervals below the ‘rhizoplane’ were measured. The hypothesis was that metals accumulate near plant roots more under wetland than dryland conditions. Patterns in element distribution were different between the treatments. Under dryland conditions Al, Ba, Cu, Cr, Fe, K, La, Mg, Na, Sr, V, Y and Zn accumulated in soil closest to the roots, above the ‘rhizoplane’ only. Under wetland conditions Al, Fe, Cr, K, V and Zn accumulated above as well as 3 mm below the ‘rhizoplane’ whereas La, Sr and Y accumulated 3 mm below the ‘rhizoplane’ only. Plants on average produced 1.5 times more biomass and element uptake was 2.5 times greater under wetland compared to dryland conditions.     

Kinetics of reductive dechlorination of 1,2,3,4-TCDD in the presence of zero-valent zinc

Polychlorinated dibenzo-p-dioxins (PCDDs) are toxic and widespread persistent organic pollutants (POPs). Cost-effective technologies for destroying or detoxifying PCDDs are in high demand. The overall purpose of this study was to develop a zero-valent zinc based technology for transforming toxic PCDDs to less- or non-toxic forms. We measured the dechlorination rates of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TCDD) in the presence of zero-valent zinc under aqueous conditions, identified the daughter compounds of the reaction, and constructed possible pathways for the reactions. The reaction rates of daughter compounds with zero-valent zinc were also measured independently. Our results showed that the zero-valent zinc is a suitable candidate for reducing PCDDs. Reductive dechlorination of 1,2,3,4-TCDD was stepwise and complete to dibenzo-p-dioxin (DD) mainly via 1,2,4-trichlorodibenzo-p-dioxin (1,2,4-TrCDD), 1,3-dichlorodibenzo-p-dioxin (1,3-DCDD), 1-chlorodibenzo-p-dioxin (1-MCDD) to DD and via 1,2,4-TrCDD, 2,3-dichlorodibenzo-p-dioxin (2,3-DCDD), 2-chlorodibenzo-p-dioxin (2-MCDD) to DD. In each separate system, the observed half-lives of 1,2,3,4-TCDD, 1,2,3-TrCDD, 1,2,4-TrCDD, 1,2-DCDD, 1,3-DCDD, 1,4-DCDD and 2,3-DCDD are 0.56, 2.62, 5.71, 24.93, 41.53, 93.67 and 169.06 h respectively. The tendency of rate constant follows TCDD>TrCDD>DCDD. Our results suggest that zero-valent zinc is a suitable candidate for rapidly reducing highly chlorinated PCDDs to less or non-chlorinated daughter products.     

RECHARGE OF THE SNAKE RWER PLAIN AQUIFER: TRANSITIONING FROM INCIDENTAL TO MANAGED1

ABSTRACT: Declining ground-water levels and spring discharges have heightened water user concerns about the sustainability of the Snake River Plain aquifer in southern Idaho. Diminished recharge from surface water irrigation and increased irrigation pumping have been depleting the aquifer at a rate of about 350,000 acre-feet/year. Previously, aquifer conditions were treated as an uncontrollable consequence of weather and development activities. With increasing competition for available water, the State appears to be progressing through a three-stage process of recharge management. The first stage is that which has occurred historically, where recharge is largely an incidental effect of surface water irrigation. The second stage is the implementation of intentional recharge with little regard to identifying or maximizing benefits. Idaho has been at this stage for the past few years. The State is entering a third stage in which recharge sites will be located and designed to meet specific water user and environmental objectives. Preliminary estimates using numerical and analytical models demonstrate that managed recharge within a few miles of the river will result in short-term increases in spring discharge. More distant recharge sites are needed to provide longer-term benefits. The primary challenge facing implementation of the managed recharge program will be the balancing of economic and environmental costs and benefits and to whom they accrue.