To: John Ford, Director From: Bob Roy County of Humboldt Planning and Building Stantec Consulting Department 30 Park Drive 3015 H Street Topsham, ME 04222 Eureka, California 95501 [email protected] Date: August 23, 2019 Reference: Operational Impacts to Raptors Humboldt Wind has commissioned Western EcoSystems Technology, Inc. (WEST) to review the draft EIR for the Humboldt Wind Project and provide a re-evaluation of the DEIR’s analysis of potential impacts to raptors. WEST is a firm that is expert in conducting ecological studies and analyzing complicated natural resource data. The attached memo provides WEST’s recommended analysis of the likely impacts of the project on raptors. As noted in WEST’s memo, the DEIR appears to overestimate what the likely impacts of the project will be on local and regional raptor populations. The DEIR reviews several data sets but does not set an explicit expectation of what the project’s likely impact will be. Rather, it reviews a range of potential impacts using different datasets and metrics, and then concludes that impacts will be significant and unavoidable after mitigation. However, WEST’s analysis provides compelling evidence that the DEIR’s analysis is flawed and that actual impacts at the project are likely to be significantly less than that stated in the DEIR and would not lead to local or regional populations of raptor species to fall below self-sustaining levels. Key to this analysis, or the difference between the two analyses, is that raptor impacts at the Humboldt project would not be similar to those documented at projects in central and southern California (where raptor use is far greater than at the project) and the fact that raptor use at the project site is very similar to that documented at Hatchet Ridge, where raptor fatalities have been found to be very low after three years of post-construction monitoring. While the DEIR speculates that raptor fatalities at the project may be as high as 114 fatalities per year, WEST provides an estimate of 25 fatalities per year, based on a thorough analysis of 82 post-construction surveys at 44 modern, comparable wind projects in California, Oregon, and Washington. Given the significant differences between raptor use and habitat at the Humboldt project compared to that at projects included in the DEIR’s assessment, WEST’s analysis provides more realistic evaluation of these potential impacts. In fact, WEST’s estimate my very well be an overestimate of the potential impacts. Based on the population data and analysis in the WEST memo, it is Stantec’s professional opinion that the project’s operational impacts on raptor populations will not be “significant” on a project-specific basis as is defined by CEQA because it will not result in population-level impacts. Nonetheless, assuming conservatively that the project could contribute to significant cumulative impacts to raptors, Stantec recommends that the County add the following language to MM 3.5-11 immediately following the reference in Measure 3.5-11 to Mitigation Measure 3.5-5c: August 23, 2019 Reference: Humboldt Wind – Operational Impacts to Raptors In addition to adherence to Mitigation Measures 3.5-5a, 3.5-5b and 3.5-5c, the applicant shall: • Underground 6 miles of existing overhead PG&E electrical distribution lines that represent existing electrocution and collision hazard for raptors. • Pay $600/raptor to a raptor rehabilitation facility such as the Humboldt Wildlife Care Center in Arcata, California. ENVIRONMENTAL & STATISTICAL CONSULTANTS 2725 NW Walnut Blvd. Corvallis, OR 97330 Phone: 541-230-1790 west-inc.com August 23, 2019 To: Mr. John Ford, Director County of Humboldt Planning and Building Department 3015 H Street Eureka, California 95501 [email protected] Subject: Humboldt Wind Energy Project Draft Environmental Impact Report (DEIR) SCH No. 201872076 – Operational Impacts to Raptors Dear Mr. Ford: This document was prepared by Western EcoSystems Technology, Inc. (WEST), on behalf of Humboldt Wind, LLC (Humboldt Wind), to provide an alternative assessment of potential operational impacts to raptors at the Humboldt Wind Project, to that provided in the project’s DEIR. The DEIR provides an evaluation of potential impacts of project operation on raptors and, based on an estimated mortality of as many as 114 raptors per year, concludes that the project would have a significant and unavoidable impact on raptors (DEIR at p. 3.5-111.). The DEIR summarizes information provided in Stantec reports and then goes on to summarize other available datasets, such as American Wind Wildlife Institute (AWWI; 2019) and post- construction reports for the nearest wind facility with available post-construction data; Hatchet Ridge (Tetra Tech 2013). Based on additional analysis, WEST suggests that the DEIR’s estimate of raptor mortality from the project should be adjusted downward. There are two main reasons we believe the DEIR’s projection of raptor mortality is an overestimate. First, in attempting to assess project-level impacts, the DEIR referenced three mortality datasets, Stantec (2018), AWWI (2019), and Tetra Tech (2013) which use different metrics of raptor mortality (i.e., fatalities/turbine and fatalities/megawatt [MW], respectively) to determine the potential range in raptor fatalities at the project. The use of a combination of these two metrics to estimate the potential for raptor mortality is not appropriate, particularly the use of fatalities/turbine which is an inappropriate unit of measurements given the range of turbines types and sizes included within those datasets. Second, the DEIR fails to take into consideration the vastly different ecological characteristics (raptor use, species assemblages, topography, prey base) between the Humboldt project and the projects in the Coastal California region which were predominantly used to generate the high end of the predicted range of fatality estimates in the DEIR (114 raptor fatalities per year). An evaluation of potential risk to raptors at the project should first consider the raptor use and species composition of raptors documented during site-specific avian use surveys. Diurnal 1 ENVIRONMENTAL & STATISTICAL CONSULTANTS 2725 NW Walnut Blvd. Corvallis, OR 97330 Phone: 541-230-1790 west-inc.com raptors were observed regularly at the project during surveys, composing 19.2% of all large bird use recorded during bird use counts from October 2017 – October 2018 (Stantec 2018). Nine diurnal raptor species were recorded, the most abundant of which were red-tailed hawk (347 of 434 total raptor observations) and American kestrel (44 observations) which together composed 90.1% of all diurnal raptor observations. This was followed by Cooper’s hawk (23 observations) and sharp-shinned hawk (seven observations), which together composed another 6.9% of diurnal raptor observations. The remaining five species (ferruginous hawk, northern harrier, bald eagle, peregrine falcon, and osprey) were represented by five or fewer individual observations recorded during 235 hours of survey. Diurnal raptor use documented during the 2017-2018 study at the project was higher in summer (2.12 birds/plot/30-min survey), and lower and more consistent during other seasons (0.34 in fall, 0.28 in winter, and 0.27 in spring). Higher use in summer was largely attributed to red-tailed hawk which composed 87.8% of diurnal raptor use during that season. To put this project-specific raptor survey data into context, WEST has compiled post- construction mortality data from a larger and more relevant subset of projects, many of which are also included in the Stantec (2018) and AWWI (2018) datasets presented in the DEIR; however, all fatality rates in the WEST analysis are presented on a raptors/MW basis. This subset of projects includes 82 post-construction fatality monitoring studies at 44 wind energy facilities in California and the Pacific Northwest (PNW, i.e., Oregon and Washington). Diurnal raptor fatality rates at these projects have ranged from zero to 1.06 fatalities/MW/year, with a mean of 0.15 fatalities/MW/year (Figures 1 and 2; Appendix A). Fatality rates from old generation turbines in the Altamont Pass Wind Resource Area (WRA), Tehachapi Pass WRA, and San Gorgonio WRA were excluded from this assessment as they likely do not reflect collision risk for raptor species from larger, more modern turbines. Based on the Humboldt Project’s nameplate generating capacity of up to 155 MW, this range in diurnal raptor fatality rates estimated for modern wind energy facilities in California and the PNW translates to an estimate of zero to 165 total diurnal raptor fatalities at the Project annually. Based on the mean of diurnal raptor mortality at California and PNW facilities (0.15 fatalities/MW/year), the projected number of diurnal raptor fatalities at the project each year is 25. To establish project-specific mortality estimates, it is also appropriate for the EIR to look towards the wind energy facility in the western US with species assemblages and topography similar to the Project. This facility is Hatchet Ridge, located approximately 125 miles east of the project (Figure 2). At Hatchet Ridge, direct impacts to birds have been low relative to other facilities in the western US. In fact, during three years of post-construction fatality monitoring conducted at Hatchet Ridge from 2011-2013, diurnal raptor fatality rates were not calculated due to low sample size (less than five fatalities found per year; Tetra Tech 2014). Given the Project’s regional proximity to Hatchet Ridge and mountainous terrain, we believe that overall direct impacts to raptors at the project would be more similar to those documented at Hatchet Ridge than to other facilities in California. Nonetheless, we recommend using the mean fatality 2 ENVIRONMENTAL & STATISTICAL CONSULTANTS 2725 NW Walnut Blvd. Corvallis, OR 97330 Phone: 541-230-1790 west-inc.com estimate of 25 raptors per year based on the relevant data set of 44 other facilities in California and the PNW.