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Abstract: The USEPA''s 2010 mercury rule, which would reduce emissions from non-hazardous waste burning cement manufacturing facilities by an estimated 94%, represents a substantial regulatory challenge for the industry. These regulations, based on the performance of facilities that benefit from low concentrations of mercury in their feedstock and fuel inputs (e.g., limestone concentration was less than 25ppb at each facility), will require non-compliant facilities to develop innovative controls. Control development is difficult because each facility''s emissions must be assessed and simple correlation to mercury concentrations in limestone or an assumption of ‘typically observed’ mercury concentrations in inputs are unsupported by available data. Furthermore, atmospheric emissions are highly variable due to an internal control mechanism that captures and loops mercury between the high-temperature kiln and low-temperature raw materials mill. Two models have been reported to predict emissions; however, they have not been benchmarked against data from the internal components that capture mercury and do not distinguish between mercury species, which have different sorption and desorption properties. Control strategies include technologies applied from other industries and technologies developed specifically for cement facilities. Reported technologies, listed from highest to lowest anticipated mercury removal, include purge of collected dust or raw meal, changes in feedstocks and fuels, wet scrubbing, cleaning of mercury enriched dust, dry sorbent injection, and dry and semi-dry scrubbing. The effectiveness of these technologies is limited by an inadequate understanding of sorption, desorption, and mercury species involved in internal loop mercury control. To comply with the mercury rule and to improve current mercury control technologies and practices, research is needed to advance fundamental knowledge regarding mercury species sorption and desorption dynamics on materials within cement facilities. [Copyright &y& Elsevier]

Abstract: The concept of “universal service obligation” (USO) has been around for decades; however, its definition continues to change. The notion that the last mile of fixed-line access should be subsidized has spread around the world, despite well reasoned arguments and empirical evidence that the policy is and was a failure. It created artificial competition. Now the concept is becoming bifurcated. Should wireless and/or broadband services be included in the definition of universal services? The purpose of the paper is to demonstrate why the definition should be expanded, although a definitive prescription is not offered. This paper is in two parts: What should constitute USO definitions and how, if at all, it should be implemented? Many consumers are “cutting-the-cord” and moving directly to alternative services. In this ubiquitous communications environment the whole set of possible communications methods should be considered when defining “universal connectivity.” Second, no one service or technology should be relied on to support subsidies. The second part of the paper addresses the policy question: How should this connectivity be achieved? [Copyright &y& Elsevier]