CERCLA-linked environmental impact and benefit analysis: Evaluating remedial alternatives for the Portland Harbor Superfund Site, Portland, Oregon, USA.

This analysis focused on evaluating the environmental consequences of remediation, providing indicators for the environmental quality pillar of 3 "pillars" of the Portland Harbor Sustainability Project (PHSP) framework (the other 2 pillars are economic viability and social equity). The project an environmental impact and benefit analysis (EIBA) and an EIBA-based cost-benefit analysis. Metrics developed in the EIBA were used to quantify and compare remedial alternatives' environmental benefits and impacts in the human and ecological domains, as a result of remedial actions (relative to no action). The cost-benefit results were used to evaluate whether remediation costs were proportionate or disproportionate to the environmental benefits. Alternatives B and D had the highest overall benefit scores, and Alternative F was disproportionately costly relative to its achieved benefits when compared to the other remedial alternatives. Indeed, the costlier alternatives with larger remedial footprints had lower overall EIBA benefit scores-because of substantially more air emissions, noise, and light impacts, and more disturbance to business, recreational access, and habitat during construction-compared to the less costly and smaller alternatives. Put another way, the adverse effects during construction tended to outweigh the long-term benefits, and the net environmental impacts of the larger remedial alternatives far outweighed their small incremental improvements in risk reduction. Results of this Comprehensive Environmental Response Compensation and Liability Act (CERCLA)-linked environmental analysis were integrated with indicators of economic and social impacts of remediation in a stakeholder values-based sustainability framework. These tools (EIBA, EIBA-based cost-benefit analysis, economic impact assessment, and the stakeholder values-based integration) provide transparent and quantitative evaluations of the benefits and impacts associated with remedial alternatives, and should be applied to complex remediation projects to aid environmental decision making. Integr Environ Assess Manag 2018;14:22-31. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Solar-driven membrane distillation demonstration in Leupp, Arizona.

The Navajo Nation is the largest and one of the driest Native American reservations in the US. The population in the Navajo Nation is sporadically distributed over a very large area making it extremely ineffective to connect homes to a centralized water supply system. Owing to this population distribution and the multi decadal drought prevailing in the region, over 40% of the 300,000 people living on Navajo Tribal Lands lack access to running potable water. For many people the only alternative is hauling water from filling stations, resulting in economic hardship and limited supply. A solution to this problem is a de-centralized off-grid water source. The University of Arizona and US Bureau of Reclamation's Solar Membrane Distillation (SMD), stand-alone, pilot desalination system on the Navajo Reservation will provide an off-grid source of potable water; the pilot will serve as a proximal water source, ease the financial hardships caused by the drought, and provide a model for low-cost water treatment systems in arid tribal lands. Bench-scale experiments and an earlier field prototype plant showed viable operation of a solar heated, membrane distillation (MD) system, but further optimization is required. The objectives of the Navajo pilot study are to i) demonstrate integration of solar collectors and membrane distillation, ii) optimize operational parameters, iii) demonstrate and monitor technology performance during extended duration operation, and iv) facilitate independent system operation by the Navajo Water Resources Department, including hand-over of a comprehensive operations manual for implementation of subsequent SMD systems. The Navajo SMD system is designed as a perennial installation that includes remote communication of research data and full automation for remote, unmanned operation.