Online Open House: April 4 - June 9, 2016
Mitigation means avoiding, minimizing, rectifying, reducing over time, and compensating for project impacts on natural resources. These actions are generally applied sequentially, with compensatory measures not considered until after all avoidance and minimization measures have been considered. Consistent with the Presidential Memorandum on Mitigation (November 3, 2015), measures need to have some connection to actual impacts of the project being analyzed, and when important, scarce, or sensitive resources are impacted, a goal of net benefit or, at a minimum, no net loss is required.
The 2013 Gateway West Final EIS Table 2.7-1 contains proposed environmental protection measures (EPMs) which the companies have adopted as design features for segments 8 and 9 that will apply to any action alternative selected. The 2013 ROD for segments 1-7 and 10 requires particular plans for mitigating effects to Greater sage-grouse habitats and migratory bird habitats, and these would also apply to segments 8 and 9 if they are approved.
If an action alternative is selected in the Final Supplemental EIS, the BLM will identify types of compensatory mitigation measures for the selected route alignments. Chapter 3, Section 220.127.116.11 of the Draft Supplemental EIS summarizes the process for determining compensatory mitigation to address any impacts that would remain once avoidance, minimization and existing compensation measures are applied.
The BLM is also developing compensatory mitigation measures for other resources that would be impacted by the project but are not covered in the mitigation plans mentioned in Chapter 3 above. The November 3, 2015, Presidential Memorandum on Mitigation, the Department of the Interior Manual, and the BLM Regional Mitigation Manual will guide development of additional measures for impacts to National Historic Trails, cultural resources, wetlands, and Snake River Birds of Prey NCA resources, objects and values.
All new routes and route variations analyzed in detail in the Draft Supplemental EIS would have some impact on NCA resources and values. Idaho Power and Rocky Mountain Power developed a set of proposed measures to offset impacts to and enhance resources in the NCA, which they call a Mitigation and Enhancement Portfolio (MEP) (Draft Supplemental EIS Appendix C).
The MEP does not provide enough detail for the BLM to determine how the goals of the proposed plan would be achieved. Current policies require the BLM to determine the measurable environmental benefits of mitigation, and the BLM is developing a model that can be used to calculate the value of habitat restoration measures in the NCA.
Appendix K of the Draft Supplemental EIS presents a conceptual framework for impacts to NCA habitats. The framework presents a method for assessing adverse impacts (debits) and beneficial effects (credits) to raptor populations from a given action and mitigation measure. The model may be revised or refined between the Draft and Final Supplemental EIS based on feedback and comments received on the Draft Supplemental EIS.
The BLM is considering the following mitigation categories to address any remaining impacts to resources: