CAREER: The Role of Microorganisms in Arsenic Contamination of Groundwater

Arsenic is the only contaminant for which exposure through drinking water has been proven to cause cancer in humans. The US Environmental Protection Agency has concluded that the present drinking water limit of 50 ug/L arsenic is not sufficiently protective and proposes a new limit of 10 ug/L. In most cases, the arsenic originates in the geologic materials of the aquifer. While correlations with bedrock types have been made, the factors that affect arsenic concentrations and speciation in drinking water are poorly understood. As(III), the reduced inorganic form, is more mobile and more toxic than As(V), thus speciation affects both the concentration and the health implications of arsenic exposure. Microorganisms probably affect As concentrations in groundwater, but the magnitude and nature of their participation in the arsenic cycle have not yet been clarified. Microorganisms can affect the chemistry of arsenic compounds in a number of ways. Laboratory and field studies as proposed in this program will build on the PI\u27s preliminary data that indicate the presence of arsenate reducing microorganisms in well water to determine how microbial activities affect soluble arsenic concentrations. This information will be used to create a conceptual model of the processes that affect As in groundwater. Molecular probes will be developed to determine the importance of the isolated arsenate-degrading microorganisms in situ. Existing geological data and field data gathered by high school and undergraduate students will be used to assess whether or not the model derived from laboratory experiments is supported by field observations. Since the project requires an interdisciplinary approach, links with microbial ecologists and environmental microbiologists will be strengthened to support the investigator\u27s research goals. The research results will form the basis of new modules in two undergraduate environmental engineering courses. An outreach program for high school students will also contribute to the collection of field data

The post-war of religious art in the Church of England : The contribution of three Jewish artists.

Abstract not available

Land Use and Socioeconomic Influences on a Vulnerable Freshwater Resource in Northern New England, United States

Land use and cover conversions as well as climatic factors drive current and future threats to freshwater systems. Research from the United States and across the globe has focused on already threatened and degraded freshwater systems, whose recovery requires significant investments. Attention must also be directed to monitoring freshwater systems that may appear robust, yet are likely to face enhanced vulnerabilities in the future due to climate and land use and cover changes. Such proactive monitoring can help identify problems early and provide potential solutions. In this study, we consider the case of Sebago Lake and its watershed in southern Maine; a region that has experienced significant population growth and development activity. Land use, socioeconomic change and water quality trends are monitored over a 20-year period using Landsat imagery, census, water quality and precipitation data. Our results indicate that Developed Land within the watershed has increased from 5.4 % of the total land area in 1987 to 8.9 % in 2009 with associated increases in population and housing activity. Sebago Lake’s water quality indicators from 1990 to 2010 show a directional trend concomitant with this change. The increase in Developed Land is likely to place additional pressures on water quality in the future. The analysis also indicates that precipitation trends play an important role in water quality variability for Sebago Lake. Predicted changes to climatic factors including enhanced spring time precipitation or earlier ice-out conditions combined with further land use change may play an influential role in determining water quality. The analysis highlights emerging areas of concern and reiterates the essential role of proactively monitoring vulnerable systems to help mitigate future threats

Maine’s Artisan Cheesemakers: The Opportunities and Challenges of Being an Artist, Scientist, Agriculturalist, Alchemist, and Entrepreneur

Maine’s artisanal cheese sector has grown rapidly in the last six years. Maine cheesemakers take a variety of approaches including those based on farmsteads and operations sourcing milk from local dairies. This study examines cheesemakers’ business operations and their approaches to sustainability, opportunities, and threats. Cheesemakers report that they derive several benefits from their enterprise, but that they face challenges to ensure their long-term sustainability

Why macropru can end up being procyclical

Discretionary macroprudential policies aim to be countercyclical by adjusting risk-taking across the financial cycle. This column argues that the opposite effect may happen in certain cases. Depending on how regulators measure risk and how they react, the eventual outcome may well be procyclical, with serious unintended consequences

Estimated Greenhouse Gas Emissions from PFAS Treatment of Maine Drinking Water

State law requires the adoption of a maximum contaminant level (MCL) for PFAS contamination in drinking water by June 1, 2024. While discussion of mitigation options has included the degree of risk reduction and the cost of treatment, indirect environmental effects are missing from the conversation. Until other technologies are developed, water treatment in Maine will likely rely on the established, energy-intensive method of PFAS adsorption (binding) to granular activated carbon. We conducted an inventory of greenhouse gas emissions associated with water treatment using this treatment media to fill gaps in the discussion. We found that greenhouse gas emissions for water treatment to bring PFAS down to the current interim standard are substantial, raising the footprint of an average user by 6.7–18 percent. We use this information to discuss implications for policymaking

Toxicants, entanglement, and mitigation in New England’s emerging circular economy for food waste

Drawing on research with food waste recycling facilities in New England, this paper explores a fundamental tension between the eco-modernist logics of the circular economy and the reality of contemporary waste streams. Composting and digestion are promoted as key solutions to food waste, due to their ability to return nutrients to agricultural soils. However, our work suggests that food waste processors increasingly find themselves responsible for policing boundaries between distinct “material” and “biological” systems as imagined by the architects of the circular economy—boundaries penetrable by toxicants. This responsibility creates significant problems for processors due to the regulatory, educational, and structural barriers documented in this research. This paper contributes to scholarship which suggests the need to rethink the modernist logics of the circular economy and to recognize the realities of entangled material and biological systems. More specifically, we argue that if circularity is the goal, policy needs to recognize the barriers food waste processors face and concentrate circularity efforts further upstream to ensure fair, just, and safe circular food systems

Moving up the Waste Hierarchy in Maine: Learning from “Best Practice” State-Level Policy for Waste Reduction and Recovery

As Maine residents look toward the future, it is increasingly clear that more sustainable waste and materials management solutions will be necessary. A recent stakeholder engagement process involving nearly 200 industry professionals, municipal representatives and citizen groups confirmed this point. As we move together toward a more sustainable waste management system, participants in the engagement process identified an outstanding need to learn more about policies options. This article responds to that need with a review of state level policies designed to reduce waste generation and increase material recovery rates. We find there are a wide variety of state-level policy tools available, each of which involves a series of complex tradeoffs to balance decision criteria ranging from diversion potential and cost to social acceptability and environmental protection. While there is no magic formula, it is clear that the most successful state-level programs are those that utilize a variety of tools, selected as part of a comprehensive and data-driven long term planning process

The Disposal Mode of Maine’s Waste Governance

Maine’s materials management system is stuck in a disposal mode of waste governance. Despite significant investments in programs and policies designed to reduce the amount of waste the state buries each year, recent shocks and uncertainties have resulted in increased waste generation and disposal. This paper analyzes specific ways through which materials management in Maine has become locked in to a disposal mode of waste governance. We build a framework to help understand various forms of lock-in and how they might be unlocked. This framework is applied to the extended producer responsibility packaging law that is presently under the rule-making process in Maine, the first state to adopt such a policy in the United States