Marine wave and tidal energy technology could interact with marine resources in ways that are not well understood. As wave and tidal energy conversion projects are planned, tested, and deployed, a wide range of stakeholders will be engaged; these include developers, state and federal regulatory agencies, environmental groups, tribal governments, recreational and commercial fishermen, and local communities. Identifying stakeholders' environmental concerns in the early stages of the industry's development will help developers address and minimize potential environmental effects. Identifying important concerns will also assist with streamlining siting and associated permitting processes, which are considered key hurdles by the industry in the U.S. today. In September 2008, RE Vision consulting, LLC was selected by the Department of Energy (DoE) to conduct a scenario-based evaluation of emerging hydrokinetic technologies. The purpose of this evaluation is to identify and characterize environmental impacts that are likely to occur, demonstrate a process for analyzing these impacts, identify the "key" environmental concerns for each scenario, identify areas of uncertainty, and describe studies that could address that uncertainty. This process is intended to provide an objective and transparent tool to assist in decision-making for siting and selection of technology for wave and tidal energy development. RE Vision worked with H.T. Harvey & Associates, to develop a framework for identifying key environmental concerns with marine renewable technology. This report describes the results of this study. This framework was applied to varying wave and tidal power conversion technologies, scales, and locations. The following wave and tidal energy scenarios were considered: 4 wave energy generation technologies 3 tidal energy generation technologies 3 sites: Humboldt coast, California (wave); Makapu'u Point, Oahu, Hawaii (wave); and the Tacoma Narrows, Washington (tidal) 3 project sizes: pilot, small commercial, and large commercial The possible combinations total 24 wave technology scenarios and 9 tidal technology scenarios. We evaluated 3 of the 33 scenarios in detail: 1. A small commercial OPT Power Buoy project off the Humboldt County, California coast 2. A small commercial Pelamis Wave Power P-2 project off Makapu'u Point, Oahu, Hawaii 3. A pilot MCT SeaGen tidal project, sited in the Tacoma Narrows, Washington. This framework document used information available from permitting documents that were written to support actual wave or tidal energy projects, but the results obtained here should not be confused with those of the permitting documents1. The main difference between this framework document and permitting documents of currently proposed pilot projects is that this framework identifies key environmental concerns and describes the next steps in addressing those concerns; permitting documents must identify effects, find or declare thresholds of significance, evaluate the effects against the thresholds, and find mitigation measures that will minimize or avoid the effects so they can be considered less-than-significant. Two methodologies, 1) an environmental effects analysis and 2) Raptools, were developed and tested to identify potential environmental effects associated with wave or tidal energy conversion projects. For the environmental effects analysis, we developed a framework based on standard risk assessment techniques. The framework was applied to the three scenarios listed above. The environmental effects analysis addressed questions such as: What is the temporal and spatial exposure of a species at a site? What are the specific potential project effects on that species? What measures could minimize, mitigate, or eliminate negative effects? Are there potential effects of the project, or species' response to the effect, that are highly uncertain and warrant additional study? The second methodology, Raptools, is a collaborative ...