The "Least Favored Method"—A Primer on the RCRA Land Disposal Regulations

In May of 1990 the U.S. Environmental Protection Agency (EPA) completed a four year long series of rulemakings on land disposal of over. 450 hazardous wastes regulated under the Resource Conservation and Recovery Act (RCRA). The new regulations stipulate that hazardous wastes may not be disposed of on land—if at all—unless they are first treated in a prescribed manner. The Land Disposal Regulations (LDRs) will change disposal requirements for approximately 41 million tons of hazardous waste annually, at a cost to the regulated community of over a billion dollars. Despite EPA’s efforts to educate industry, the LDRs remain a source of confusion for many. This article is intended to clear up at least some of the confusion by providing an overview of the regulations and the decision-making processes which occurred during the four years of EPA rulemakings and, more recently, in the courts.     

Effect of Gasoline Formulation on the Formation of Photosmog: A Box Model Study

Abstract

Based on exhaust gas analyses from the combustion of five different types of gasoline in a passenger car operated on a chassis dynamometer, box model simulations of the irradiation of exhaust/NO_x /air mixtures using an established chemical mechanism for a standardized photo-smog scenario were performed. The fuel matrix used covered wide fractional ranges for paraffinic, olefinic, and aromatic hydrocarbons. Two fuels also contained methyl tertiary butyl ether (MTBE). The different O₃ profiles calculated for each run were compared and interpreted. The O₃ levels obtained were strongly influenced by the exhaust gas concentrations of aromatic and olefinic hydro-carbons. The higher exhaust content of these compounds caused higher O₃ production in the smog system investigated. The conclusion of the present study is that the composition of gasoline cannot be taken directly for the estimation of the emissions’ O₃ creation potential from its combustion. Variation of the dilution in the different calculations showed evidence for an additional influence of transport effects. Accordingly, further detailed exhaust gas analyses followed by more complex modeling studies are necessary for a proper characterization of the relationship between fuel blend and gasoline combustion products.     

Influence of global change on phytoplankton and nutrient cycling in the Elbe River

The effects of changing climatic and socioeconomic conditions on the water quality of the Elbe River were investigated using the deterministic model QSim. Since the impact of global change on river water quality marks the endpoint of various processes in the catchment and in the atmosphere, this study was performed within a network of interacting models that determined input parameters for water quality simulations. The development of phytoplankton and nutrient concentrations under conditions of global change was modeled along a 700 km stretch of the river. The simulations revealed a strong, scale-dependent effect of climate change on phytoplankton biomass, leading to a longitudinal shift of the dominating processes (primary productivity vs. respiration) along the river continuum. Under reduced flow, combined with increasing temperature and global radiation, phytoplankton biomass increased and phytoplankton maxima shifted in upstream direction, followed by higher system respiration rates in the adjacent downstream sections. In contrast, higher flow shifted the phytoplankton maximum toward the downstream sections. Even a drastic reduction of phosphorus inputs from anthropogenic sources had only limited influence on algal biomass, due to the ability of algal cells to store phosphorus. A strong reduction in P-inputs especially in the headwaters would be necessary to counterbalance the possible climate-induced effects on algal biomass.     

Assessment of the environmental persistence and long-range transport of endosulfan

Concentrations of the insecticide endosulfan (α- and β-isomer) and its degradation product endosulfan sulfate in air, seawater and soil are calculated with the global environmental fate model CliMoChem. As model input, physicochemical properties of all three compounds were assembled and a latitudinally and temporally resolved emission inventory was generated. For concentrations in air, model and measurements are in good agreement; a bimodal seasonality with two peaks in spring and fall as it is observed in Arctic air is reproduced by the model. For seawater, the agreement of model and measurements depends on the values of the hydrolysis activation energy of endosulfan used in the model; with relatively high values around 100 kJ/mol, model results match field data well. The results of this assessment of the levels, persistence, and global distribution of endosulfan are also relevant for the evaluation of endosulfan as a Persistent Organic Pollutant under the Stockholm Convention.     

Climate change impacts on critical international transportation assets of Caribbean Small Island Developing States (SIDS): the case of Jamaica and Saint Lucia

This contribution presents an assessment of the potential vulnerabilities to climate variability and change (CV & C) of the critical transportation infrastructure of Caribbean Small Island Developing States (SIDS). It focuses on potential operational disruptions and coastal inundation forced by CV & C on four coastal international airports and four seaports in Jamaica and Saint Lucia which are critical facilitators of international connectivity and socioeconomic development. Impact assessments have been carried out under climatic conditions forced by a 1.5 °C specific warming level (SWL) above pre-industrial levels, as well as for different emission scenarios and time periods in the twenty-first century. Disruptions and increasing costs due to, e.g., more frequent exceedance of high temperature thresholds that could impede transport operations are predicted, even under the 1.5 °C SWL, advocated by the Alliance of Small Island States (AOSIS) and reflected as an aspirational goal in the Paris Climate Agreement. Dynamic modeling of the coastal inundation under different return periods of projected extreme sea levels (ESLs) indicates that the examined airports and seaports will face increasing coastal inundation during the century. Inundation is projected for the airport runways of some of the examined international airports and most of the seaports, even from the 100-year extreme sea level under 1.5 °C SWL. In the absence of effective technical adaptation measures, both operational disruptions and coastal inundation are projected to increasingly affect all examined assets over the course of the century.     

Creating and sustaining community capacity for ecosystem-based management: Is local government the key?

Recently, collaborative approaches to natural resource management have been widely promoted as ways to broaden participation and community involvement in furthering the goals of ecosystem management. The language of collaboration has even been incorporated into controversial legislation, such as the US Healthy Forests Restoration Act of 2003. This research examines collaboration and sharing management responsibility for federal public land with local communities through a case study of the Ashland Municipal Watershed in southern Oregon. A policy sciences approach is used to analyze community participation and institutional relationships between the US Department of Agriculture, Forest Service, and local city government in the planning processes of five land management actions occurring over a 7-year period. The knowledge gained from examining differing approaches to planning and decision making in the Ashland watershed is used to suggest future planning processes to develop and sustain the community capacity necessary to support implementation of community-based ecosystem management.