The Impact of Existing and Potential Wind Power Development on High-Value Scenic Resources in Maine

The impact of existing and potential wind power development on high-value scenic resources in Maine

APPALACHIAN MOUNTAIN CLUB

The impact of existing and potential wind power development on high-value scenic resources in Maine

David Publicover and Catherine Poppenwimer Appalachian Mountain Club Research Department Gorham, NH

AMC Technical Report 19-1 November 2019

Acknowledgements Funding for this project was provided by the Horizon Foundation, the Sally Mead Hands Foundation and five individual donors. We thank them for the support. We also thank our Maine Audubon Society colleagues Sarah Haggerty, Eliza Donohue, Sally Stockwell and Susan Gallo for their assistance and support during this project. Suggested citation Publicover, D. and C. Poppenwimer. 2019. The impact of existing and potential wind power development on high-value scenic resources in Maine. AMC Technical Report 19-1. Appalachian Mountain Club, Gorham, NH.

This study was undertaken as part of a collaborative project with Maine Audubon Society. MAS has released a companion report titled “Renewable Energy and Wildlife in Maine: Avoiding, Minimizing and Mitigating Impacts to Wildlife and Habitat from Solar, Wind and Transmission Facilities”, available at https://www.maineaudubon.org/advocacy/climate-energy/.

EXECUTIVE SUMMARY

Overview This project was undertaken to better understand the visual impact of existing wind power projects on high-value scenic resources in Maine (especially mountains and large lakes), how these impacts have been evaluated in permitting decisions, and the potential for future impacts to these resources from proposed or potential projects. The information was developed to better inform the on-going discussion on the future development of this renewable energy technology in Maine’s landscape. In particular, it seeks to address the question of whether the existing standards for evaluating the scenic impacts of wind power development are adequate given the state’s growing experience with this technology. Wind power has emerged as an important source of renewable energy generation in Maine, accounting for 21% of all the electricity generated in the state in 2017 and 2018. The fourteen grid-scale projects currently operating in Maine, which include 372 turbines with a combined capacity of 904 megawatts (MW), span the state from Aroostook County to the Downeast and Western Mountains regions. The rapid advancement of this technology over the past decade has not been without controversy, with the potential for adverse scenic impacts a major point of contention. There is no question that wind turbines are a highly visible feature in the landscape, and the potential visibility of wind turbines has increased due to their ever-greater height, from under 400 feet in 2007 to nearly 600 feet today. Permitting of wind power projects is governed by the Maine Wind Energy Act, originally enacted in 2003 and significantly amended in 2008. The 2008 amendments enacted the recommendations of the Governor’s Task Force on Wind Power Development established by former Governor John E. Baldacci. The amendments made several changes to existing law with the goal of easing the permitting of wind power development, including establishing an “expedited permitting area” (EPA) in which certain requirements were relaxed, most notably changing how scenic impacts are evaluated within the EPA. These changes included limiting the evaluation of scenic impacts to a defined set of Scenic Resources of State and National Significance (SRSNSs) within eight miles of a project. Beyond eight miles scenic impacts are deemed by law to be “insignificant”. This project consisted of the following steps:  Conducting a literature review of the scenic impact of wind power projects.  Evaluating the extent of the commercially viable and potentially available wind resource across the state at heights of 100 and 140 meters (328 and 459 feet).  Determining the number of existing and proposed grid-scale projects within 3, 8 and 15 miles of 59 “high value scenic resources” (HVSRs), including 28 trail-accessible mountain summits and 31 lakes greater than 1000 acres in size and rated “outstanding” for scenic value.  Determining the number of existing projects within 3, 8 and 15 miles of the 346 great ponds defined as SRSNSs.  Reviewing permitting decisions to determine how permitting agencies made decisions about scenic impacts of existing wind projects.  Conducting bare-earth viewshed studies for hypothetical projects at five potential development sites to determine the potential impact to scenic resources beyond eight miles.

Literature review While there are numerous general descriptions of the visual impact of wind power projects in the literature, there are few studies that evaluate the visibility of projects at different distances. However, the available literature indicates that wind power projects can be a major focus of visual attention at distances of 10 to 12 miles and under clear conditions can be visible at 25 miles. Recommendations for the evaluation of scenic impacts (particularly from highly sensitive viewpoints) generally extend to 10 or 15 miles. The literature does not support the current legal standard in Maine that visual impacts beyond eight miles should always be considered “insignificant”. Maine’s wind resource At a height of 100 meters (the hub height of turbines commonly in use in Maine) the “viable wind resource” encompasses about 17% of the state, with 42% of that area lying within the EPA (excluding conservation land). At a height of 140 meters (above the hub height of current turbines but within the range of turbines that could be used in the near future), the viable wind resource encompasses 62% of the state with almost half of this within the EPA. While taller turbines may have greater scenic impact, they also greatly expand the area where wind power development is viable, allowing projects to be sited in less visually sensitive areas. There are numerous other constraints on wind power development beyond wind speed, and how much of this resource is realistically developable is unknown. Existing wind power projects and scenic resources Overall a relatively small number of the scenic resources we evaluated have been impacted by wind power development within eight miles:  Of the 59 HVSRs (28 summits 31 lakes), none have an existing project within three miles; the two projects that have been proposed in such close proximity to an HVSR (Redington/Black Nubble and Bowers Mountain) were denied permits due to their scenic impact.  Five HVSRs (8%) have a project that would be fully or partially visible within eight miles.  Of the 346 great pond SRSNSs, 18 (5%) have at least partial visibility of a project within eight miles, of which four would have extensive visibility of a project within three miles. Notable regulated scenic resources that have been impacted by wind power projects within eight miles are Mount Blue (Saddleback Ridge project), Tumbledown Mountain (Record Hill project), Nicatous Lake (Passadumkeag project) and Donnell Pond (Bull Hill project). Other regulated scenic resources that have been significantly impacted by wind power development, but were deemed to be of lower scenic significance during permitting, include Tunk Mountain (Bull Hill and Hancock projects), Mattawamkeag and Pleasant Lakes (Oakfield project), Narraguagus Lake (Bull Hill project) and Saponac Pond (Passadumkeag project). Review of regulatory decisions These projects provide a good indication of where the permitting agencies have drawn the line between acceptable and unacceptable scenic impacts. The 2008 amendments to the law concede that some level of scenic impact from wind power development is acceptable. By themselves, close proximity to a project, full visibility of a project, or high significance of the scenic resource has been insufficient to deem an impact unreasonable. Factors cited in permitting decisions as mitigating against a finding of unreasonable adverse scenic impact (even when the impact was recognized as being adverse) include the distance of the project from the scenic resource (with projects in the outer part of the eight mile zone deemed of lower impact), the extent of project visibility, the significance of the scenic resource, the level and nature

of public use, and the results of user surveys. Only two projects have included a review of cumulative impacts, both of projects in close proximity to each other in the Downeast region. These reviews provide little guidance on how cumulative impacts may be evaluated in the future. Scenic impacts not considered under current law This assessment focused on regulated scenic resources. However, there are other scenic impacts that are not considered under the current law, including impacts to scenic resources not defined as SRSNSs (such as 86% of great ponds in the state) as well as views from private businesses, residences, camps and lands and most public roads. Consideration of these impacts is intended to be addressed during municipal permitting, though they receive no consideration in the unorganized territories Most notable for this assessment are impacts beyond the current eight mile regulatory limit. There are considerably more projects within 15 miles of scenic resources than there are within eight miles:  Eight of the 59 HVSRs have an existing project within eight miles but 24 (41%) have a project within 15 miles.  Thirty-six of the great pond SRSNSs have an existing project within eight miles but 99 (29%) have a project within 15 miles.  Nine of the HVSRs have a proposed project within eight miles but 26 (44%) have one within 15 miles. Anecdotal evidence from users of scenic viewpoints indicates that existing projects are readily visible (though not dominant) at distances beyond eight miles, with notable examples including the Bingham project from Moxie Bald, the Record Hill project from Baldpate Mountain, and the Groton Wind project from Cardigan Mountain in New Hampshire. The proposed (but subsequently withdrawn) Highland Wind project would have been fully visible within 15 miles from the summit of Bigelow Mountain, but only 6 of the project’s 48 turbines lay within eight miles of Avery Peak and none within eight miles of West Peak. Had the project proceeded through permitting, most or all of it would have been considered legally invisible from these viewpoints. In addition, for at least four projects only a portion of the project lay within eight miles of an HVSR, precluding consideration of the full visual impact. The eight mile limit may also preclude full consideration of cumulative impacts, which will become more relevant as additional projects are developed. While four HVSRs (one summit and three lakes) have more than one existing and proposed project within eight miles, nineteen (seven summits and twelve lakes) have multiple existing and proposed projects within 15 miles. While cumulative impacts to lakes from projects beyond eight miles are be less likely to be found unreasonable, there is greater potential for significant cumulative impacts from summits with panoramic views. Viewshed case studies The viewshed case studies also illustrate the limitations of the eight mile limit. For a hypothetical project on Misery Ridge (site of the proposed Somerset project), only a miniscule portion of Moosehead Lake lies within eight miles, but large parts of the lake (as well as Big Moose Mountain) would have extensive views of the project in the 8 to 15 miles range. Similarly, most of Rangeley Lake would have extensive views of a hypothetical project on Deer Mountain in the 8 to 15 mile range. The scenic impact on Moosehead or Rangeley lakes if these sites were developed would be significant but would not be considered during project permitting. For the three case studies in the Downeast Lakes region there was little additional visibility from HVSRs in the 8 to 15 mile range, though there would be some potential visibility from other great pond SRSNSs.

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Recommendations In its 2012 review of the 2008 amendments to the Wind Energy Act, the Governor’s Office of Energy Independence and Security included the following recommendation: “Amend the wind law to require scenic impact evaluations to eight miles, with a fifteen mile standard option and provisions made for review to greater distances.” The precedents set by the permitting of existing projects indicate that in most cases impacts beyond eight miles are unlikely to be considered unreasonably adverse, and full implementation of this recommendation does not appear warranted. However, our assessment indicates there are at least some situations where scenic impacts beyond eight miles should be considered, most notably where there would be extensive views of a project from more significant viewpoints. Thus, we offer the following recommendations: RECOMMENDATION 1: Require consideration of visual impact where the evidence indicates that there would be visibility of a project at distances between 8 and 15 miles from a SRSNS of high or medium value as determined under rules adopted by the Maine Department of Environmental Protection. RECOMMENDATION 2: Extend the distance for analyzing cumulative impacts to 15 miles for any SRSNS of high or medium value as determined under rules adopted by the Maine Department of Environmental Protection. RECOMMENDATION 3: When only a portion of a project lies within eight miles of SRSNS, assessment of visual impacts shall consider the entire project including those portions lying more than eight miles from the SRSNS. While scenic impacts beyond eight miles are less likely to be considered unreasonable, in certain situations the failure to consider these impacts will reduce public confidence in the permitting process. Adoption of these recommendations would increase the credibility of the permitting process, increase confidence in the ability of Maine’s laws to adequately consider impacts to the state’s most significant scenic resources, and help to more fully realize the Governor’s Task Force’s objective to ensure that wind power development does not degrade Maine’s quality of place.

Table of Contents

EXECUTIVE SUMMARY ...... i INTRODUCTION ...... 1 BACKGROUND ...... 2 LITERATURE REVIEW ...... 4 METHODS ...... 6 Viable wind resource ...... 6 Scenic resources ...... 7 Existing and proposed projects ...... 9 Review of permitting decisions ...... 10 Viewshed case studies ...... 10 RESULTS ...... 12 Viable wind resource ...... 12 High Value Scenic Resources and existing projects ...... 13 Great ponds and existing projects ...... 14 Cumulative impact of existing projects ...... 15 Review of permitting decisions ...... 15 HVSR summits ...... 15 HVSR lakes ...... 16 Great pond SRSNSs ...... 16 Cumulative impacts ...... 17 Projects denied a permit ...... 17 Proposed projects and potential for future development ...... 17 Viewshed case studies ...... 18 DISCUSSION ...... 19 RECOMMENDATIONS ...... 22 REFERENCES ...... 24 APPENDIX A ...... 41

List of tables 1. High Value Scenic Resources (HVSRs) considered in this analysis ...... 7 2. Existing and proposed projects considered in this analysis ...... 10 3. Distribution of viable wind resource (terrestrial only) ...... 12 4. Number of High Value Scenic Resources with an existing project within the specified distance ...... 13 5. High Value Scenic Resources with existing projects within 15 miles ...... 14 6. Number of High Value Scenic Resources with a proposed project within the specified distance ...... 17 7. Number of High Value Scenic Resources with multiple existing or proposed projects within the specified distance ...... 18

List of figures 1. Installed wind power capacity in Maine ...... 1 2. Increasing height of wind turbines in Maine ...... 1 3. Comparative size of Maine turbines since 2007 ...... 2 4. High Value Scenic Resources (HVSRs) considered in this analysis ...... 8 5. Existing, permitted and proposed grid-scale projects included in the analysis ...... 11 6. Viable wind resource at a hub height of 100 meters ...... 26 7. Viable wind resource at a hub height of 140 meters ...... 27 8. High Value Scenic Resources with 8 miles and 15 miles of the Record Hill wind project . . . 28 9. Hypothetical projects for viewshed case studies ...... 29 10. Bare-ground viewsheds of a hypothetical Deer Mountain wind power project ...... 31 11. Bare-ground viewsheds of a hypothetical Misery Ridge wind power project ...... 33 12. Bare-ground viewsheds of a hypothetical Stetson Mountain wind power project ...... 35 13. Bare-ground viewsheds of a hypothetical Tracy Mountain wind power project ...... 37 14. Bare-ground viewsheds of a hypothetical Weatherbee Hill wind power project ...... 39

INTRODUCTION Wind power has emerged as an important source of renewable energy generation in Maine. There are now 923 megawatts (MW) of installed wind power capacity in the state including 386 turbines across 18 projects (AWEA 2019, USDOE 2019), with another 22-turbine 73 MW project approved but not yet constructed (MDEP 2019). This is nearly twice the wind power capacity of the other New England states combined, though development has slowed in recent years (Fig. 1). In 2017 and 2018 wind power accounted for 21% of all the electricity generated in the state, up from less than 1% in 2008 (USEIA 2019). The fourteen grid-scale projects currently operating, which include 372 turbines with a combined capacity of 904 MW, span the state from Aroostook County to the Downeast and Western Mountains regions. The rapid advancement of this technology over the past decade has not been without controversy, with the potential for adverse scenic impacts a major point of contention. Wind power projects are now visible at various distances from viewpoints across the state from mountaintops to state highways. Two projects have been denied permits because of their potential visual impact to high value scenic resources (Redington/Black Nubble in 2007/08 and Bowers Mountain in 2013), and others (both Figure 1. Installed wind power capacity in Maine. constructed and proposed) have faced significant opposition. There is no question that wind turbines are a highly visible feature in the landscape, and the siting of these projects faces many challenges due to the presence of highly valued recreational and scenic resources throughout the state. In addition, the potential visibility of wind turbines has increased due to their ever- greater height (Figs. 2, 3). The first large- scale project in Maine (Mars Hill, completed in 2007) had turbines that were 389 feet tall to the top of the blades. Currently many projects have turbines that are nearly 500 feet tall, with the tallest at 574 feet (the Hancock project in Downeast Maine).1 The recently permitted Weaver Wind project in Downeast Maine will use turbines that are 591 feet tall. However, taller turbines do Figure 2. Increasing height of wind turbines in Maine. Each bar have advantages. By allowing projects to represents an individual grid-scale project. capture the higher wind speeds at greater distance from the ground, they are expanding the area with

1 These were the tallest commercial turbines in North America, but they have since been exceeded by a project under construction in Texas utilizing 590-foot-tall turbines. Onshore turbines over 630 feet tall are currently operating in Europe with taller ones under consideration.

commercially viable wind speeds and potentially allowing projects to be sited in less visually sensitive areas.

Figure 3. Comparative size of wind turbines in Maine since 2007. This analysis was undertaken to better understand the impact of existing wind power projects on high- value scenic resources (especially mountains and large lakes), how these impacts have been evaluated in permitting decisions, and the potential for future impacts to these resources from proposed projects. The information was developed to better inform the on-going discussion on the future development of this renewable energy technology in Maine’s landscape. In particular, it seeks to better inform the question of whether the existing standards for evaluating scenic impacts of wind power development are adequate given the state’s advancing experience with understanding these impacts and the ever-increasing height of wind turbines. We conclude with several recommendations for changes to the current regulatory structure to allow more complete consideration of impacts to high value scenic resources. This study was part of a cooperative project undertaken in partnership with the Maine Audubon Society, which has issued a companion report that focuses on wildlife habitat considerations (Haggerty and Stockwell 2019). Their report contains additional background on climate change and issues related to the development of wind power, solar power and transmission lines in Maine.

BACKGROUND Permitting of wind power projects is governed by the Maine Wind Energy Act (35-A MRS, Ch. 34), originally enacted in 2003 and significantly amended in 2008. The 2008 amendments (35-A MRS. Ch. 34-A) enacted the recommendations of the Governor’s Task Force on Wind Power Development established by former Governor John Baldacci (GTFWPD 2008). At that time permitting of wind power projects was split between the Maine Land Use Regulation Commission (LURC) (for the unorganized territories) and the Maine Department of Environmental Protection (MDEP) (for organized towns). With the reorganization of LURC into the Land Use Planning Commission (LUPC) in 2012 all permitting was transferred to MDEP under the Site Location of Development Law. However, the standards established in 2008 remain part of the permitting requirements.

The 2008 amendments made several changes to existing law with the goal of easing the permitting of wind power development. The law established an “expedited permitting area” (EPA)2 in which certain requirements were eased, and made wind power an allowed used within all LUPC zoning subdistricts (eliminating the requirement for rezoning to a development subdistrict). While no specific changes were made to regulatory standards related to natural resource impacts (soil, water quality, wildlife, etc.)3, the evaluation of scenic impacts within the expedited permitting area was substantially changed. The changes included:  Eliminating the requirement that development “fits harmoniously into the existing natural environment”.  Limiting consideration of scenic impacts to a defined set of Scenic Resources of State and National Significance (SRSNSs), including: o A national natural landmark, federally designated wilderness area or other comparable outstanding natural and cultural feature. o Properties listed on the National Register of Historic Places. o State and national parks. o Great ponds with outstanding or significant scenic value identified in the Maine Wildlands Lakes Assessment or Maine Lakes Study. o A river segment with outstanding or significant scenic value identified in the Maine Rivers Study. o Scenic viewpoints on hiking trails as designated in rule by the Department of Agriculture, Conservation and Forestry. o Designated highway scenic turnouts. o Scenic viewpoints in coastal areas.  Establishing criteria for the evaluation of scenic impact based on factors including the significance of the potentially affected SRSNSs, the existing character of the surrounding area, expectations of the typical viewer, the purpose and context of the proposed activity, the extent, nature, and duration of public use of the SRSNSs, and the scope and scale of the potential impact.  Requiring a visual impact assessment (VIA) for impact on scenic resources within three miles of the project and the option for the permitting agency to require one out to eight miles.4  Requiring that any visual impact more than eight miles from the project shall be considered “insignificant”. The limitation of consideration of visual impacts to eight miles from a project was based on the conclusions of a National Academy of Sciences report (NAS 2007), which stated, “The most significant [visual] impacts are likely to occur within 3 miles of the project, with impacts possible from sensitive

2 The expedited permitting area includes all organized towns (about 50% of the area of the state) and about one- third of the unorganized territories, primarily areas in proximity to existing public roads and transmission lines but excluding the more remote undeveloped core. 3 One exception to this is that by making wind power an allowed use in LURC protection subdistricts (such as high mountain areas subject to P-MA zoning), the law eliminated the requirement that rezoning to a development subdistrict maintain a “substantially equivalent level of protection” as the prior protection subdistrict. 4 To date all developers have conducted their VIA out to eight miles, making the three mile zone moot in practice.

viewing areas up to 8 miles of the project.” The NAS study was based on an evaluation of existing projects in the mid-Atlantic region with turbines less than 400 feet tall. There have been a number of amendments to the law subsequent to 2008 that addressed identified limitations of the law, including requiring the use of “best practical mitigation” to minimize project impacts5, providing greater protection for high elevation areas containing habitat for the rare Bicknell’s thrush (Catharus bicknelli), and providing a one-time opportunity for residents of the unorganized territory to petition to have their township removed from the expedited permitting area.6 The only amendment addressing scenic issues has been a requirement that permitting consider the cumulative impact of multiple projects on a SRSNS. The 2008 law also included a requirement that the Governor’s Office of Energy Independence and Security conduct a study within five years of the state’s experience with the new permitting process and make recommendations for any changes that were warranted. This study was completed in 2012 (GOEIS 2012). Among its recommendations was to “Amend the wind law to require scenic impact evaluations to eight miles, with a fifteen mile standard option and provisions made for review to greater distances.” In subsequent years legislation has been proposed to enact this recommendation (or more limited variations of it) but to date no changes to the law have been made.7 In 2018 the Department of Environmental Protection adopted rules (06-096 CMR Ch. 382 §3) that provide additional guidance on the statutory standards for scenic review, including evaluation of a project’s associated facilities (roads and transmission lines), the evaluation criteria (character of the area, expectations of viewers, etc.) and evaluation of cumulative impact.

LITERATURE REVIEW In contrast to the literature on the wildlife impacts of wind power (summarized in Haggerty and Stockwell 2019), detailed studies of the visual impact of wind power facilities are more limited. There are sources on the general nature of these impacts, guidance on the assessment and minimization of visual impacts, and numerous assessments of the potential visual impact of individual projects. However, there are few studies that assess the actual visibility of existing wind turbines at different distances as a guide to establishing visual impact analysis thresholds. In the northeastern United States the primary reference for visual impacts remains the 2007 National Academy of Sciences report, which was based on an assessment of turbines less than 400 feet tall (the size of the Mars Hill turbines). However, even then the report recognized that visual impacts could extend to greater distances than the eight miles used as the basis for the current law. The report stated: “At 10 miles away the project is less likely to result in significant impacts unless it is located in or can be seen from a particularly sensitive site or the project is in an area that might be considered a regional focal point. Thus, a 10-mile radius provides a good basis for analysis including viewshed mapping and field

5 One technology that has been implemented on some recent projects to mitigate scenic impacts is radar-activated lighting, which turns on nighttime warning lights required by the Federal Aviation Administration only when on-site radar detects an aircraft in the vicinity of the project. This technology was approved for use on wind turbines by the FAA in 2015. 6 Residents of 39 townships successfully petitioned to be removed from the EPA (LUPC 2017). 7 This has included legislation proposed by the Appalachian Mountain Club in cooperation with other organizations.

assessment for current turbines. In some landscapes a 15-mile radius may be preferred if highly sensitive viewpoints occur at these distances, the overall scale of the project warrants a broader assessment, or if more than one project is proposed in an area.” In a study of western landscapes conducted for the Bureau of Land Management by the Argonne National Laboratory, Sullivan et al. (2012) concluded: “Under favorable viewing conditions, the wind facilities were judged to be major foci of visual attention at up to 19 km (12 mi) and likely to be noticed by casual observers at >37 km (23 mi). A conservative interpretation suggests that for such facilities, an appropriate radius for visual impact analyses would be 48 km (30 mi), that the facilities would be unlikely to be missed by casual observers at up to 32 km (20 mi), and that the facilities could be major sources of visual contrast at up to 16 km (10 mi).” In a widely-used guide to assessing the visual impact of wind energy projects, Vissering (2011) stated: “Modern wind projects using 2.0+ MW turbines are easily visible at 15-20 miles’ distance in clear weather conditions, but the most significant impacts are likely to occur in closer proximity, in most cases within 5-8 miles in northeastern landscapes. However, a larger study area provides a more comprehensive understanding of the resources involved within the region, and 10 miles may provide a good guideline for analysis in northeastern regions. An area of analysis of 25 miles will be more appropriate in midwestern and western landscapes, open terrain, drier air, and larger wind projects (hundreds vs. dozens of turbines) creating a larger mass visible over greater distances.” In an earlier study, Bishop (2002) assessed viewer reactions to photosimulations of wind turbines at different distances in an open Australian landscape. The simulated turbines were 3-bladed monopole structures (similar to those currently used) but were only 250 feet tall. Despite their small size he concluded, “In areas with completely transparent skies, visibility modelling out to 20 km - 30 km [12 – 18 miles] is justified, but effects beyond 20 km may be rare and depend on exceptional viewing conditions.” In a guidance document on siting wind farms, Scottish Natural Heritage (2017) states, “Wind turbines of between 100 – 150 m [328 – 492 feet] can be visible at distances of up to 40 or 50 km [25 to 31 miles] in some conditions.” In a separate document (SNH 2012) they recommend a study area radius of 35 km (22 miles) for assessing cumulative impacts. In a study of the visibility of offshore wind turbines in the United Kingdom8 (also conducted by the Argonne National Laboratory), Sullivan et al. (2013) concluded, “The observed wind facilities were judged to be a major focus of visual attention at distances up to 16 km (10 mi), were noticeable to casual observers at distances of almost 29 km (18 mi), and were visible with extended or concentrated viewing at distances beyond 40 km (25 mi).” The authors also drew two general conclusions that are relevant to this issue:  “A long-term, ongoing trend of developing and deploying larger wind turbines in larger facilities, however, is well documented for both onshore and offshore projects, and visibility limits calculated for older wind facilities with fewer and smaller turbines could be invalid for the larger facilities and turbines currently being deployed.”

8 While offshore wind turbines are often much larger than onshore turbines, the projects included in this study had turbines ranging in height from 351 to 502 feet in total height, which are comparable to those currently installed in Maine.

 “To date, no systematic US study specific to onshore wind turbine visibility has been published. However, the ongoing investigations and repeated observations of onshore wind facilities reported here suggest that turbines are visible at greater distances than was previously noted in published research.” Only a few other states in the Northeast have regulations that specify required distances for visual impact assessments for wind power projects. In many states permitting of these facilities is done at the local level. In addition to Maine, those states that specify required distances include:  New Hampshire: A minimum of 10 miles.  Vermont: 10 miles.  Connecticut: Variable radius based on turbine height: less than 200 feet - 2 miles; between 200 feet and 400 feet – 4 miles; between 400 feet and 600 feet – 6 miles; greater than 600 feet – 8 miles; and 10 miles for projects of greater than 65 MW.  West Virginia: 20 miles. While the available evidence is limited, and conclusions drawn from studies in different areas with different conditions must be interpreted with caution, the available literature indicates that wind power projects can be a major focus of visual attention at distances of 10 to 12 miles and in clear conditions can be visible at 25 miles. This is consistent with anecdotal evidence received from users of scenic resources. These studies and the standards from other states do not support the current legal standard in Maine that visual impacts beyond eight miles should always be considered “insignificant”.

METHODS This project sought to address the following questions:  To what extent have high value scenic resources in Maine been impacted by existing wind power projects?  What is the potential for additional impacts to these resources from future development?  How have permitting decisions evaluated scenic impacts to these resources?  Are there scenic impacts to these resources that are not adequately considered under current permitting rules?

Viable wind resource Commercially-available wind resource data for Maine were obtained from AWS Truepower (now UL LLC) (UL 2019). These data included modeled wind speed at a resolution of 200-meter grid cells. Data were obtained for turbine hub heights of both 100 and 140 meters (328 and 459 feet); assuming a standard 100-meter (328-foot) rotor diameter this represents total turbine heights of 492 and 623 feet respectively. The former height is common in existing and proposed projects in Maine. The latter is taller than any currently present in the US, but turbines of this height are operating in Europe and could be considered in Maine in the not-too-distant future. The “viable wind resource” at both 100 and 140 meters (areas with sufficiently strong wind to support a commercial project under current conditions) was delineated based on procedures developed by Maine Audubon Society in a previous study (MAS 2013), supplemented by an examination of the relationship between currently operating and proposed turbines and wind speed (see Appendix A).

We calculated the proportion of the terrestrial viable wind resource (excluding open water) at both heights in three categories: 1) on conservation land, 2) outside of the EPA excluding conservation land, and 3) within the EPA excluding conservation land.

Scenic resources Our experience has shown that open mountain summits and large lakes are among the resources that are most likely to raise concerns about the scenic impact of wind power development. We therefore focused our attention on the following subset of SRSNSs, which we call “high value scenic resources” (HVSRs) (Table 1, Fig. 4):  28 trail-accessible mountain summits, many of which lie along the Appalachian Trail. Most offer panoramic views from open summits, though in some cases views may be limited to certain directions.  31 lakes over 1000 acres in size rated outstanding for scenic value; these are a subset of the full list of 346 great ponds SRSNSs.

Table 1. High Value Scenic Resources (HVSRs) considered in this analysis. Summits Lakes Name County Elev. (ft) Name County Size (acres) Bald Mountain Franklin 2461 Alligator Lake Hancock 1159 Baldpate Mountain Oxford 3576 Attean Pond Somerset 2745 Barren Mountain Piscataquis 2434 Bald Mountain Pond Somerset 1152 Bemis Mountain Franklin 3560 Debsconeag Lake (3rd) Piscataquis 1011 Bigelow Mtn (West Peak) Somerset 4009 Donnell Pond Hancock 1120 Big Moose Mountain Piscataquis 3173 Fish River Lake Aroostook 2642 Cadillac Mountain Hancock 1512 Grand Lake (West) Washington 14340 Caribou Mountain Oxford 2818 Holeb Pond Somerset 1055 Coburn Mountain Somerset 3461 Jo-Mary Lake (Lower) Piscataquis 1910 Cranberry Peak Franklin 2982 Jo-Mary Lake (Middle) Penobscot 1152 Crocker Mountain Franklin 4196 Jo-Mary Lake (Upper) Piscataquis 1873 Goose Eye Mountain Oxford 3714 Kennebago Lake Franklin 1700 Little Bigelow Mountain Somerset 2992 Long Pond Somerset 3053 Mount Abraham Franklin 4045 Megunticook Lake Knox/Waldo 1328 Mount Blue Franklin 3192 Moosehead Lake Piscataquis 74890 Mount Katahdin Piscataquis 5246 Mooselookmeguntic Lake Oxford 16300 Moxie Bald Mountain Somerset 2503 Moxie Pond Somerset 2370 Old Blue Mountain Franklin 3579 Musquash Lake (West) Washington 1613 Old Speck Mountain Oxford 4144 Nahmakanta Lake Piscataquis 1024 Pleasant Pond Mountain Somerset 2447 Nicatous Lake Hancock 5165 Saddleback Junior Franklin 3635 Onawa Lake Piscataquis 1344 Saddleback Mountain Franklin 4039 Pemadumcook Chain Lake Piscataquis 18300 Spaulding Mountain Franklin 3999 Penobscot Lake Somerset 1019 Sunday River Whitecap Oxford 3307 Pierce Pond Somerset 1650 The Horn Franklin 3947 Pleasant Lake Washington 1574 Tumbledown Mountain Franklin 3012 Rainbow Lake Piscataquis 1664 Tunk Mountain Hancock 1066 Rangeley Lake Franklin 6000 White Cap Mountain Piscataquis 3638 Richardson Lake (Upper) Oxford 4200 Seboeis Lake Piscataquis 4201 Spencer Lake Somerset 1819 Tunk Lake Hancock 2010

Figure 4. High Value Scenic Resources (HVSRs) considered in this analysis.

While it was beyond the scope of this project to assess all SRSNSs defined under the current law, we also assessed the extent to which existing projects were located in proximity to the 346 great ponds9 that are defined as SRSNSs under the law (i.e., those rated outstanding or significant for scenic value in the Maine Wildlands Lakes Assessment and Maine’s Finest Lakes study). These represent about 14% of the nearly 2,400 great ponds evaluated in these assessments. For each of the High Value Scenic Resources we determined the number of existing and proposed projects within 0 to 3 miles, 3 to 8 miles and 8 to 15 miles of the HVSR. Projects were assigned to a single zone based on the distance of the closest turbine. For the full set of great pond SRSNSs we identified the number of existing projects within each of the three zones.

Existing and proposed projects Existing and proposed projects were identified from a range of sources. Location and height of turbines was obtained from the Federal Aviation Administration’s Obstruction Analysis/Airport Airspace Analysis database (January 2018 version) converted to GIS shapefiles by the US Fish & Wildlife Service (USFWS 2019). Some proposed projects listed in the FAA database were excluded when available sources indicated that they were no longer under consideration. Other projects that had not submitted hazard determination requests for turbines to the FAA (but had submitted the location of meteorological towers) were included based on sources including project web sites and news reports. However, the current status of most proposed projects, and whether they are being actively pursued, is unknown. We included the 14 existing10 and 10 permitted or proposed11 grid-scale projects subject to state-level permitting under the Site Law in our analysis (Table 2, Fig. 5). We limited our assessment to resources that included some part of the expedited permitting area within 15 miles. There were several additional HVSRs that could have been considered but the 15-mile zone around them lay entirely outside of the EPA.12 To date there have been no permit applications for wind power development outside of the EPA, and we assume that this pattern will continue in the future. While wind power development is not prohibited outside of the EPA it would be subject to the more difficult permitting standards that were in effect prior to 2008, and it was the clear intent of both the Governor’s Task Force and the legislature that development take place within the EPA.13 However, one project in the FAA database (Horse Mountain in northern Aroostook County) is located outside of the EPA. Other than the FAA submission no information on this project could be found.

9 The list in the Maine Wildlands Lakes Assessment includes multiple entries for a few large lakes such as Moosehead (which includes separate listings for eight separate sections) and Pemadumcook Chain Lake. These were evaluated as single lakes, resulting in a total of 335 lakes. 10 Of the fourteen grid scale projects, three (Mars Hill, Kibby Mountain and Stetson) were permitted before the 2008 amendments to the Maine Wind Energy Act were adopted. 11 This includes the recently permitted Weaver project. It does not include the 11-turbine expansion of the Kibby Mountain project which was permitted in 2011 but which has not proceeded since that time. 12 Big Spencer Mountain and Lobster, Ragged, Telos, Allagash and Munsungan lakes. 13 The legislative finding related to the establishment of the EPA [35-A MRS §3402(2)] stated that it was in the public interest to encourage wind power development “in places where it is most compatible with existing patterns of development and resource values when considered broadly at the landscape level.”

Table 2. Existing and proposed projects considered in this analysis. Name County Operational Turbines Capacity (MW) Height (ft)

EXISTING

Bingham Piscataquis/Somerset 2016 56 185 492 Bull Hill Hancock 2012 19 34 476 Canton Mountain Oxford 2017 8 23 448 Hancock Hancock 2016 17 51 574 Kibby Mountain Franklin 2010 44 132 410 Mars Hill Aroostook 2006 28 42 389 Oakfield Aroostook 2015 48 148 459 Passadumkeag Penobscot 2016 13 42 462 Record Hill Oxford 2012 22 50 412 Rollins Penobscot 2011 40 60 389 Saddleback Ridge Franklin 2015 12 34 448 Spruce Mountain Oxford 2011 10 20 407 Stetson Washington 2009 38 57 389 Stetson II Washington 2010 17 26 389

PROPOSED Alder Stream* Franklin Bryant Mountain Oxford 12 493 Everpower Downeast Hancock/Washington 121 610 Great Northern Aroostook 38 492 Horse Mountain Aroostook 16 492 Moose Mountain Aroostook 10 492 Moose Wind Piscataquis/Somerset 22 493 Number Nine Aroostook 129 499 Somerset* Somerset Weaver (permitted) Hancock 23 73 591 *Information is limited to meteorological tower locations.

Review of permitting decisions We examined the permitting decision documents for permitted and denied projects to assess the extent and nature of these impacts and the standards by which scenic impacts to the most significant scenic resources were determined to be acceptable or unacceptable. We examined all documented impacts on HVSRs and great pond SRSNSs as well as the limited number of cumulative impacts examined in recent permitting decisions.

Viewshed case studies Finally we conducted viewshed analysis case studies for five potential wind power development sites to determine the potential visibility of hypothetical projects developed on these sites. These sites were chosen because of their proximity to multiple HVSRs. The analysis extended for viewshed distances of 8 and 15 miles from the site and was intended to identify scenic resources that would have a view of the project but which would be excluded from consideration during permitting under current law. For each site turbines were spaced at a typical distance along the ridgeline. Visibility was determined for turbines with hub heights of both 100 and 140 meters; we assessed the visibility of the nacelle at this height but ignored visibility of blades above the nacelle. The analysis utilized 30-meter resolution USGS Digital Elevation Model data to develop a “bare ground” viewshed that did not include the screening effect of

Figure 5. Existing, permitted and proposed grid-scale projects included in the analysis.

forest vegetation. As such, the analysis significantly overstates the visibility from forested areas where the tree cover would screen the turbines from view, though they would be visible if tree cover was removed through harvesting or natural disturbance. However, since we focused on visibility from lakes and open summits (where forest cover is not present) this factor should not affect the conclusions drawn from the analysis. The five sites included:  Deer Mountain (northwest of the Rangeley Lakes).  Misery Ridge (west of Moosehead Lake and the site of the proposed Somerset project).  Stetson Mountain (north of the Downeast Lakes region; this is the site of two existing projects with 80-meter hub height turbines; it was included to evaluate the effect of redeveloping it with taller turbines).  Tracy Mountain (northeast of the Downeast Lakes region).  Weatherbee Hill (northwest of the Downeast Lakes region).

RESULTS

Viable wind resource At a hub height of 100 meters the viable wind resource encompasses nearly 17% of the state (about 3.3 million acres) (Table 3, Fig. 6a14). Of this about one-quarter lies on conservation land15, about one-third outside of the EPA excluding conservation land and about 42% within the EPA excluding conservation land. The latter may be considered the “available wind resource” given current permitting standards. The greatest concentration of available viable wind resource is along the coast and in eastern Aroostook County (Fig. 6b). At a hub height of 140 meters the Table 3. Distribution of viable wind resource (terrestrial only). Percent % of viable viable wind resource is considerably more extensive and includes about of state wind resource 62% of the state (Fig. 7a), of which 100 meter hub height Total 16.8 100.0 nearly half lies within the EPA On conservation land 4.4 26.2 outside of conservation land (Fig. Outside EPA (excl. conservation land) 5.4 32.0 7b). At this height the available Within EPA (excl. conservation land) 7.0 41.8 wind resource encompasses nearly the entire eastern third of the state. 140 meter hub height Total 62.3 100.0 On conservation land 15.0 24.0 Outside EPA (excl. conservation land) 16.3 26.3 Within EPA (excl. conservation land) 31.0 49.7

14 Figures 6 and 7 are located at the end of the report. 15 Wind power development is not prohibited on all conservation lands, but it is prohibited in many areas and for most other conservation lands development would be inconsistent with the conservation values of the property. For purposes of this assessment we consider conservation land to be unavailable for development. The one exception is the Moosehead Region Conservation Easement, which specifically allows wind power development in three areas west of Moosehead Lake (including Misery Ridge).

High Value Scenic Resources and existing projects Of the high value scenic resources (HVSRs) considered in this analysis (28 summits and 31 lakes), none have an existing project within three miles16. Four summits and four lakes have at least one project in the 3 to 8 mile zone, with one summit having two projects within eight miles (Tables 4, 5). The visual impacts of these projects on these HVSRs would have been considered during permitting. Our review of permitting decisions showed that:  From two lakes and one summit, the project would not be visible or be minimally visible.  From two lakes the project would be partially visible at distances of five to eight miles.  For three summits encompassing four projects, the project would be fully visible at distances of five to eight miles, though in three cases the project spanned the eight mile limit and only turbines within eight miles were considered.

Six additional summits and 10 additional lakes Table 4. Number of High Value Scenic Resources with have at least one project in the 8 to 15 mile zone, an existing project within the specified distance. the visual impact of which would not have been <3 miles <8 miles <15 miles considered during permitting. In total 8 out of the 59 HVSRs (14%) have a project within eight Summits 0 4 10 miles but 24 out of 59 (41%) have at least one Lakes 0 4 14 project within 15 miles. No information is available on the actual visibility of projects in the 8 to 15 mile zone and we did not assess their visibility.17 It is likely that most projects within 15 miles of the summit HVSRs would be visible, as these are regional high points with mostly panoramic views. However, the extent to which projects are visible from the lake HVSRs is less clear and it is likely that many would have minimal or no visibility due to the gentler topography of eastern Maine or intervening ridgelines in the western mountains region. The results are similar when considering these distance zone around individual projects. Of the fourteen existing grid-scale projects, six have at least one HVSR within eight miles, but eleven have at least one HVSR within 15 miles. Two projects have multiple HVSRs within eight miles but seven projects have multiple HVSRs within 15 miles. As an example, the Record Hill project has two summit HVSRs within eight miles but six within 15 miles (Fig. 8, end of report).18 How the presence of these additional HVSRs would have affected the permitting of these projects if they had been considered is unknown.

16 The two projects that were proposed within three miles of a HVSR (Redington and Bowers Mountain) were denied permits due to unreasonable adverse impact on scenic values. 17 An exception is the Kibby Mountain project, which conducted its visual impact assessment to a distance of 15 miles. Of the four HVSRs within 15 miles of the project (one summit and three lakes), only Cranberry Peak would have a view of it, though most of the project is located beyond 15 miles from the peak (LURC 2008a). 18 Two additional HVSRs (Upper Richardson and Mooselookmeguntic lakes) also lie within 15 miles of the project but these are unlikely to have a view of the project given the intervening mountains along the Appalachian Trail.

Table 5. High Value Scenic Resources with existing projects within 15 miles. Projects within 3 to 8 miles Projects within 8 to 15 miles HVSR summits Mount Blue Saddleback Ridge Canton Mountain, Record Hill Old Blue Mountain Record Hill Tumbledown Mountain Record Hill Saddleback Ridge Tunk Mountain Hancock, Bull Hill Baldpate Mountain Record Hill Bemis Mountain Record Hill Cranberry Peak Kibby Mountain Moxie Bald Mountain Bingham Pleasant Pond Mountain Bingham Sunday River Whitecap Record Hill

HVSR lakes Bald Mountain Pond Bingham Donnell Pond Bull Hill Hancock Nicatous Lake Passadumkeag Rollins Tunk Lake Bull Hill Hancock Alligator Lake Hancock, Bull Hill, Passadumkeag Attean Pond Kibby Mountain Grand Lake (West) Stetson Holeb Pond Kibby Mountain Mooselookmeguntic Lake Record Hill Moxie Pond Bingham Musquash Lake (West) Stetson Pleasant Lake Stetson, Stetson II Spencer Lake Kibby Mountain Upper Richardson Lake Record Hill

Great ponds and existing projects Of the 335 great pond SRSNSs19 considered under current law:  Eight have a project within three miles.  An additional 28 (for a total of 36) have at least one project within eight miles.  An additional 63 (for a total of 99) have at least one project within 15 miles. The 36 great pond SRSNSs with an existing project within eight miles represent about 11% of the total number of great ponds considered under the law and encompass 11 different projects. Ten ponds are within eight miles of two projects, making 46 separate great pond/project pairings that would have been considered. Based on our review of permitting decisions, these include:  25 where the project would not be visible or would be minimally visible.  11 where the project would be partially visible at distances of five to eight miles.  3 where the project would be partially visible within three miles.

19 See footnote 9.

 3 where the project would be fully visible at distances of four to eight miles.  4 where the project would be mostly or fully visible within three miles. These are discussed in “Review of permitting decisions” below. Of these 36 great ponds with a project within eight miles, 12 were rated “outstanding” for scenic value, four of which had two projects within eight miles. These 16 cases include:  11 where the project would not be visible or would be minimally visible.  5 where the project would be partially visible at distances from five to eight miles. These include two HVSRs (Nicatous Lake and Donnell Pond) and three smaller ponds (Jim, Halfmoon and Jackson).

Cumulative impact of existing projects Maine law requires consideration of the cumulative impact of multiple wind power projects on a scenic resource. This provision was enacted in 2015 and projects permitted before then would not have been subject to this requirement. Consideration of cumulative impacts is subject to the eight mile limit for visual impacts. Of the 59 HVSRs considered in this analysis, only one (Tunk Mountain) currently has two existing projects within eight miles but seven have at least two projects within 15 miles. Of the great pond SRSNSs, 10 have two projects within eight miles but 32 have at least two projects within 15 miles. In most cases, the actual visibility of these projects from scenic resources beyond a distance of eight miles is unknown and was not assessed. Because of the recent enactment of the cumulative impact requirement, only one permitted project (Weaver Wind) has been required to address it. However, MDEP also included cumulative impact considerations in its review of the scenic impacts of the Hancock project. These are discussed in the next section.

Review of permitting decisions HVSR summits. Four HVSR summits lie within eight miles of five projects (Table 5) and were considered during permitting:  The Saddleback Ridge project from Mount Blue. All 12 turbines would be visible from the summit, though only five were within the eight mile limit, with the closest being 7.4 miles distant. This impact was judged to be of “Low-Medium” severity and not unreasonable (MBEP 2013a).  The Record Hill project from Old Blue. A two-mile stretch of the Appalachian Trail encompassing the summit of Old Blue would lie 7.8 miles from the project at its closest. Most of this stretch would not have a view of the project due to intervening topography (MDEP 2009).  The Record Hill project from Tumbledown Mountain. The entire project would be visible from viewpoints on Tumbledown Mountain; the maximum visibility would be at distances from 5.7 to 8.6 miles, with lower mountains between the project and the viewpoints. MDEP determined this impact to be not unreasonably adverse, though no additional discussion or explanation was provided (MDEP 2009).  The Bull Hill project from Tunk Mountain. The entire project would be visible at distances of 4.9 to 7.2 miles. While LURC’s visual consultant deemed the impact to be “very adverse”, the impact

was deemed to be not unreasonably adverse due to low levels of public use, the most significant view being in the opposite direction from the project, and the fact that the majority of the mountain was in private ownership (The Nature Conservancy) and thus did not legally qualify as a SRSNS at that time (LURC 2011).  The Hancock project from Tunk Mountain. Four of the project’s turbines would be visible at a distance of seven miles, with the remainder lying beyond eight miles. This impact would be incremental to the closer and more numerous Bull Hill turbines and was deemed to be not unreasonable (MDEP 2013a). (In this decision the summit was considered a SRSNS due to its designation by MBPL rule.) HVSR lakes. Four HVSR lakes lie within eight miles of a project (Table 5) and were considered during permitting:  The Passadumkeag project from Nicatous Lake. Most of the lake is located more than eight miles from the project. Up to eight turbines would be intermittently visible from portions of the northern third of the lake at distances of five to eight miles. The impact was deemed to be adverse but not unreasonably so (MBEP 2013b).  The Bingham project from Bald Mountain Pond. Only three turbines would be visible from a small portion of the pond at a distance of seven miles or more (MDEP 2014).  The Bull Hill project from Donnell Pond and Tunk Lake. On Donnell Pond, some turbines would be visible at distances greater than five miles and the view includes existing development. The impact was described as adverse but deemed to be not unreasonable. Tunk Lake would have no views of the project (LURC 2011). Great Pond SRSNSs. Thirty-six great pond SRSNSs have a project within eight miles. The impacts of these projects on these ponds vary widely (see “Great ponds and existing projects” above); in over half of the cases the project would not be visible from the pond. Based on our review of permitting decisions, the most significant impacts include two cases discussed under “HVSR lakes” above (Passadumkeag/Nicatous Lake and Bull Hill/Donnell Pond) and four cases where projects would be a dominant feature in close proximity to a great pond:  The Bull Hill project from Narraguagus Lake. The project would be a dominant visual feature from the lake at distances as close as two miles. The decision document (LURC 2011) states that the project would be “highly visible” but noted that the lake was rated “significant” rather than “outstanding” for scenic value and that “This Lake has existing development, a lack of developed public access, relatively low use levels – mostly for fishing - and a relatively low scenic rating compared to other SRSNS.”  The Oakfield project from Mattawamkeag and Pleasant Lakes. Turbines would be highly visible from most of Pleasant Lake (1,832 acres) and lower Mattawamkeag Lake (3,330 acres). However, the decision document (MDEP 2012) noted that the lakes were rated “significant” rather than “outstanding”, were not remote and contained existing development, and that the project was unlikely have a significant negative impact on recreational uses of the lakes.  The Passadumkeag project from Saponac Pond. The project would be mostly or fully visible from the pond at distances of two to five miles. MDEP initially ruled the impact to be unreasonably adverse but this decision was reversed by the Maine Board of Environmental Protection (MBEP 2013b). While recognizing that the impact would be adverse, the board cited the relatively low

scenic significance of the pond, the presence of existing development, low levels of public use, and the results of user surveys in its decision. Cumulative impacts. Consideration of cumulative impacts has been included in two permitting decisions:  Hancock Wind project. In its review of this project, MDEP considered the scenic impact of the project in combination with the existing Bull Hill project on Lower Lead Mountain Pond, Narraguagus Lake and Tunk Mountain (MDEP 2013a). The cumulative impact was deemed to be not unreasonable. In all cases the Hancock project would be seen within the same viewing angle as the Bull Hill project, and for Narraguagus Lake and Tunk Mountain a small number of Hancock turbines would be seen in combination with the closer and more numerous Bull Hill turbines. Hancock turbines beyond eight miles from these resources were excluded from the assessment.  Weaver Wind project. The cumulative impact of this project in combination with the existing Hancock and Bull Hill projects was considered from Narraguagus Lake and Upper and Middle/Lower Lead ponds. The impact was deemed not unreasonable due to the close proximity of the three projects and the limited views of some of them from the scenic resources (MDEP 2019). Projects denied a permit. Two projects have been denied permits:  Redington/Black Nubble (2007/08). This project predated the adoption of the current permitting standards in 2008 and its denial was a major factor leading to the establishment of the Governor’s Task Force. It would have been a highly visible feature from multiple high-elevation viewpoints along a 32-mile stretch of the Appalachian Trail from Saddleback to Sugarloaf Mountains, including a view at less than five miles from the alpine ridgeline along Saddleback Mountain. The project’s potential scenic impacts were so severe that it was actively opposed by the National Park Service (LURC 2008b).  Bowers Mountain (2013). This project would be visible from eight great pond SRSNSs within eight miles, most notably Pleasant Lake which was rated “outstanding” for scenic value and which would have a view of most or all of the project at distances as close as 2.4 miles. MDEP found the combined impact on multiple great ponds to constitute an unreasonable adverse impact (MDEP 2013b).

Proposed projects and potential for future development

The pattern for proposed projects is similar to Table 6. Number of High Value Scenic Resources with a that for existing projects, in that there are proposed project within the specified distance. significantly more projects located 8 to 15 miles from the HVSRs than within eight miles of them. <3 miles <8 miles <15 miles No projects are proposed within three miles of Summits 0 2 6 any of the HVSRs (Table 6). Proposed projects are Lakes 0 7 20 located within eight miles of two summit HVSRs and seven lake HSVRs20, and within 8 to 15 miles of an additional four summit HSVRs and thirteen lake HSVRs. Other than the permitted Weaver project, only one of these projects has submitted a permitting

20 This includes the permitted Weaver Wind project, located within eight miles of Alligator Lake. The project would not be visible from the lake.

application to MDEP (Number Nine, which was subsequently withdrawn. The current status of these projects is unknown.

There is also greater potential for future Table 7. Number of High Value Scenic Resources with cumulative impacts beyond eight miles (Table 7), multiple existing or proposed projects within the with a significantly higher number of HVSRs specified distance. having multiple existing or proposed projects <3 miles <8 miles <15 miles within 15 miles than within 8 miles. Summits 0 1 7 Most HVSRs have thousands of acres of available wind resource both within eight miles and in the Lakes 0 3 12 8 to 15 mile range. However, there appears to be little relationship between the extent of available wind resource and the risk of development. Three of the HVSRs with the greatest extent of available wind resource in the 8 to 15 mile range are Tunk Mountain, Tunk Lake and Donnell Pond. The great majority of the available wind resource within 15 miles of these features is located in the coastal region to the south of them, but the projects within 15 miles are located to the north of them in smaller areas of available wind resource. In contrast, Moxie Bald lies in the lower half of HVSRs for available wind resource in the 8 to 15 mile range but it was sufficient to support the state’s largest wind power project (Bingham).

Viewshed case studies The five case studies (Figs. 9a-9e21) varied in the effect on the selected HVSRs of extending the viewshed distance from 8 to 15 miles with a 100-meter hub height:  Deer Mountain (Fig. 10a). At eight miles visibility of the project from the HVSRs includes the upper three-quarters of Mooselookmeguntic Lake, Upper Richardson Lake and Bald Mountain. When extended to 15 miles the viewshed also includes the lower portion of Mooselookmeguntic Lake, much of Rangeley Lake and Bemis Mountain along the Appalachian Trail.  Misery Ridge (Fig. 11a). At eight miles visibility of the project from the HVSRs is limited to Coburn Mountain and very small area in the western part of Moosehead Lake. However, at 15 miles the viewshed includes large parts of Moosehead Lake as well as Big Moose Mountain. There is also limited visibility from small parts of Long Pond and Moxie Pond.  Stetson Mountain (Fig. 12a). No HVSRs lie within eight miles of this site. West Musquash Lake and the northern tip of West Grand Lake lie near the outer edge of the 15 mile zone but neither would have a view of the project.  Tracy Mountain (Fig. 13a). West Musquash Lake is within eight miles of this site but the project would not be visible. West Grand Lake lies within 15 miles but the project would not be visible.  Weatherbee Hill (Fig 14a). No HVSRs lie within eight miles of this site. At 15 miles there would be limited visibility from the northern portion of West Grand Lake. For two of these hypothetical projects (Deer Mountain and Misery Ridge), the current eight-mile limit for consideration of visual impact would preclude review of potentially significant impacts to high value scenic resources (Rangeley Lake, Moosehead Lake and Big Moose Mountain) at distances of 8 to 15 miles.

21 Figures 9 through 14 are located at the end of the report.

The impacts of extending the viewshed to 15 miles are much less significant for the three hypothetical projects in the Downeast Lakes region. For none of these projects would there be major visibility from HVSRs in the 8 to 15 mile range. However, we looked at only a very limited subset of the scenic resources that would need to be considered in permitting. Other large great pond SRSNSs that comprise the core of the Downeast Lakes region (including but not limited to Pleasant, Scraggley, Junior, and Upper and Lower Sysladobsis Lakes) lie within the 8 to 15 mile zone of one or more of the three potential development sites we considered. While there is very limited visibility of the potential Stetson and Tracy Mountain projects from these lakes, there is some degree of visibility of the potential Weatherbee Hill project from them. For all five case studies, increasing the hub height from 100 to 140 meters (Figs. 10b-14b) did not change the broad pattern of visibility of these hypothetical projects, which appears to be determined primarily by topography. There was some limited expansion of the visible area and “infilling” within the broad areas with visibility of the projects22. However, in many areas there was a notable increase in the number of turbines that would be visible. Thus while increasing the turbine height did not significantly increase the extent of project visibility, it did increase the magnitude of visibility in areas from which the project would be visible.

DISCUSSION Two of the underlying objectives of the Governor’s Task Force on Wind Power Development established in 2007 were “To make Maine a leader in wind power development” and “To protect Maine’s quality of place and natural resources” (GTFWPD 2008). Maine’s undeveloped scenic landscape is highly valued, and the increasing presence of wind turbines throughout the state and the potential for additional development has created a backlash among some people about their visual impact (e.g. Bangor Daily News 2017). This project was undertaken to examine the extent to which existing wind power projects have impacted some of the state’s most significant scenic resources (especially mountains and large lakes), how these impacts have been evaluated in permitting decisions, and the potential for future impacts to these resources from proposed projects. This information is intended to inform discussions about the effectiveness of Maine’s current permitting standards in protecting Maine’s “quality of place”. Evaluation of scenic impacts during permitting is governed by the standards set by the 2008 amendments to the Maine Wind Energy Act, which enacted the recommendations of the Governor’s Task Force. Within the expedited permitting area (EPA), consideration of these impacts is limited to a defined set of Scenic Resources of State and National Significance (SRSNSs) within eight miles of a project. Three existing projects were permitted prior to the enactment of these amendments, while 11 have been permitted since then and one more has been recently permitted but not yet constructed. We examined the extent to which existing projects lay within eight miles of 59 “high value scenic resources” (HVSRs), including 28 trail-accessible mountain summits (most of which provide panoramic views) and 31 lakes greater than 1,000 acres in size rated “outstanding” for scenic character. These are among the resources most likely to be considered of high significance during permitting, and which are

22 It is important to note that these are bare ground viewsheds and do not include the screening effects of vegetation. Projects would have limited visibility from within forested areas, thus these maps significantly overestimate the potential visibility in these areas.

likely to be the most sensitive to public concern over scenic impacts. We also reviewed the presence of existing projects within eight miles of the 346 great ponds defined as SRSNSs under the law Overall a relatively small number of the scenic resources we evaluated have been impacted by wind power development within eight miles. Of the 59 HVSRs, none have an existing project within three miles23, and five (8%) have a project that would be fully or partially visible within eight miles. Of the full set of great pond SRSNSs, 18 (5%) have at least partial visibility of a project within eight miles. Of these, four have extensive visibility of a project within three miles and three have extensive visibility of a project between three and eight miles. The most notable scenic resources that have been impacted by wind power projects within eight miles are Mount Blue (Saddleback Ridge project), Tumbledown Mountain (Record Hill project), Nicatous Lake (Passadumkeag project) and Donnell Pond (Bull Hill project). In all cases the projects were more than five miles from the scenic resource, which was a major factor in the permitting decisions. Other regulated scenic resources that have been significantly impacted by wind power development, but were deemed to be of lower scenic significance during permitting, include Tunk Mountain (Bull Hill and Hancock projects), Mattawamkeag and Pleasant lakes (Oakfield project), Narraguagus Lake (Bull Hill project) and Saponac Pond (Passadumkeag project). The permitting decisions for approved projects (as well as the limited precedents provided by the two projects that have been denied permits) give a good indication of where the permitting agencies have drawn the line between acceptable and unacceptable scenic impacts. The 2008 amendments to the law concede that some level of scenic impact from wind power development is acceptable. By themselves, close proximity to a project, full visibility of a project, or high significance of the scenic resource have been insufficient to deem an impact unreasonably adverse – it appears to take a combination of multiple adverse factors. Factors cited in permitting decisions as mitigating against a finding of unreasonable adverse scenic impact (even when the impact was recognized as being adverse) include the distance of the project from the scenic resource (with projects beyond five miles deemed of lower impact), the extent of project visibility, the significance of the scenic resource, the level and nature of public use, and the results of user surveys conducted by applicants (when the surveys indicated that the project would not significantly diminish the use or enjoyment of the scenic resource for most users). This assessment focused on regulated scenic resources. However, there are other scenic impacts that are not considered under the current law, including impacts to scenic resources not defined as SRSNSs (such as 86% of great ponds in the state) as well as views from private businesses, residences, camps and lands and most public roads. The law anticipated that consideration of these impacts would be dealt with during municipal permitting in organized towns, though they receive no consideration in the unorganized territories. For some projects these impacts have created significant local concern and opposition, most notably the Rollins and Record Hill projects, both of which are located in close proximity to lakes or ponds not defined as SRSNSs. One area where the permitting judgements could be questioned is in the treatment of great pond SRSNSs. In multiple permitting decisions the fact that the great pond was only rated “significant” rather than “outstanding” for scenic value, even when the impact was recognized as adverse, was a major mitigating

23 The two projects that have been proposed within three miles of an HVSR (Redington/Black Nubble and Bowers Mountain) were denied a permit due to adverse scenic impacts.

factor (see “Review of permitting decisions” above). However, great ponds defined as SRSNSs represent only 14% of the nearly 2,400 great ponds in the state, and have already passed a screening process that determined them to have met a minimum level of scenic value. Eighty-six percent of great ponds in the state receive no consideration for scenic impacts during state permitting, but the permitting precedents further diminished the value of many great pond SRSNSs (which are already a very limited subset of all great ponds) as not being significant enough. The current eight mile limit has also precluded consideration of some scenic impacts. Other than Connecticut, Maine is the only state that specifically limits consideration of scenic impacts to this small a viewshed. Anecdotal evidence from existing projects has shown that turbines can be easily visible beyond this distance (especially from open summits), confirming the conclusions of Vissering (2011), the National Academy of Sciences report (2007) and others sources that documented visibility of projects up to 30 miles away. Maine certainly has highly sensitive viewpoints that are critical to the state’s quality of place, including Moosehead Lake, the high peaks along the Appalachian Trail, the large lakes in Downeast Maine and the Rangeley Lakes region and many coastal regions. While available studies and examples from other jurisdictions are limited, and conclusions drawn from other landscapes and conditions must be applied with caution, the available evidence does not support the current legal standard that visual impacts beyond eight miles from a project should be considered “insignificant” in all cases. There are considerably more projects within 15 miles of scenic resources than there are within eight miles. Eight of the 59 HVSRs have an existing project within eight miles but this number grows to 24 with one or more projects within 15 miles. Thirty-six of the 335 great pond SRSNSs have a project within eight miles but 99 have a project within 15 miles. The same pattern holds for proposed projects – nine of the HVSRs have a proposed project within eight miles but 26 have at least one within 15 miles. Distance alone does not indicate that a project is visible, and based on our review of permitting decisions it is likely that the great majority of the potential scenic impacts beyond eight miles would be insignificant or deemed not unreasonable. However, there are exceptions. The most notable example of the effect of the eight mile limit is Bingham project, which at its closest is located just over eight miles from the summit of Moxie Bald along the Appalachian Trail. The project occupies a wide angle of view, with 41 of its 56 turbines within 12 miles and the entire project within 15 miles. While direct observation has shown that part of the project is readily visible from this viewpoint, the decision document (MDEP 2014) notes that there are no views from AT viewpoints within eight miles, and thus this impact received no consideration during permitting. However, the developer recognized that there would be an impact and voluntarily negotiated a mitigation agreement with Appalachian Trail organizations that provided $700,000 for protection of other AT viewsheds (AMC 2014). For at least four projects24 consideration of impacts to a HVSR were truncated by the eight mile limit, precluding consideration of the full visual impact of the project. For example, from the summit of Mount Blue, five of the Saddleback Ridge turbines are visible at distances of 7.4 to 8 miles, while seven turbines are visible between 8 and 9 miles and were not considered during permitting. The proposed (but subsequently withdrawn) Highland Wind project would have been fully visible within 15 miles from the summit of Bigelow Mountain. However, only 6 of the project’s 48 turbines lay within eight miles of Avery

24 Mount Blue/Saddleback Ridge, Tumbledown Mountain/Record Hill, Tunk Mountain/Hancock and Nicatous Lake/Passadumkeag.

Peak, and none within eight miles of West Peak. Had the project proceeded through permitting, most or all of it would have been considered legally invisible from these viewpoints. The viewshed case studies also illustrate the limitations of the eight mile limit. For a hypothetical project on Misery Ridge25, only a miniscule portion of Moosehead Lake lies within eight miles, but large parts of the lake (as well as Big Moose Mountain) would have extensive views of the project in the 8 to 15 miles range. Similarly, Rangeley Lake would have extensive views of a hypothetical project on Deer Mountain in the 8 to 15 mile range. The scenic impact on Moosehead or Rangeley lakes if these sites were developed would be significant but would be completely ignored during project permitting. Whether these impacts would be deemed unreasonable during permitting cannot be known, but failure to consider them would almost certainly reduce public confidence in the permitting process. For the three case studies in the Downeast Lakes region there was little additional visibility from HVSRs in the 8 to 15 mile range, though there would be some potential visibility from other great pond SRSNSs from one of the hypothetical projects. The eight mile limit also precludes full consideration of cumulative impacts, which will become more relevant as additional projects are developed. While cumulative impacts to great ponds from projects beyond eight miles may be less likely to be found unreasonable, there is greater potential for significant cumulative impacts from summits. Open summits providing panoramic views of broad landscapes could have a view of multiple projects in different directions. As an example, Moxie Bald has an existing project just beyond eight miles and a proposed project just beyond eight miles in the opposite direction. Neither the individual nor the cumulative impact of these projects have or would receive permitting consideration. Whether these cumulative impacts would be considered unreasonable cannot be known, but the failure to at least consider them also seems unreasonable.

RECOMMENDATIONS In its review of the 2008 amendments to the Wind Energy Act, the Governor’s Office of Energy Independence and Security included the following recommendation (GOEIS 2012): “Amend the wind law to require scenic impact evaluations to eight miles, with a fifteen mile standard option and provisions made for review to greater distances.” The first part of this recommendation is moot as all applications to date have included visual impact analyses to eight miles. Regarding the second part of this recommendation, the precedents set by the permitting of existing projects indicate that in most cases impacts beyond eight miles are unlikely to be considered unreasonably adverse. However, our assessment indicates there are at least some situations where scenic impacts beyond eight miles should be considered. We offer the following recommendations: RECOMMENDATION 1: Require consideration of visual impact where the evidence indicates that there would be visibility of a project at distances between 8 and 15 miles from a SRSNS of high or medium value as determined under rules adopted by the Maine Department of Environmental Protection. These are primarily situations where there would be extensive visibility of a large project from a significant viewpoint at a distance beyond eight miles. The most obvious examples that justify this expansion are the permitted Bingham project as viewed from Moxie Bald, the proposed Somerset

25 This is the site of the proposed Somerset Wind project. The current status of this project is unknown.

project on Misery Ridge as viewed from Moosehead Lake and the previously proposed Highland Wind project as viewed from Bigelow Mountain26. While these scenic impacts have been and would be considered insignificant under current law, experience with the visibility of existing projects, as well as the conclusions of the 2007 National Academy of Sciences study and other references, indicate that this conclusion is difficult to justify and should be revisited. RECOMMENDATION 2: Extend the distance for analyzing cumulative impacts to 15 miles for any SRSNS of high or medium value as determined under rules adopted by the Maine Department of Environmental Protection. Particularly from open summits, the potential for cumulative scenic impacts from multiple projects within 15 miles should not be ignored. Only one HVSR summit has multiple existing and proposed projects within eight miles, but seven have multiple such projects within 15 miles. RECOMMENDATION 3: When only a portion of a project lies within eight miles of SRSNS, assessment of visual impacts shall consider the entire project including those portions lying more than eight miles from the SRSNS. In a few cases a project was or would be fully visible from a scenic resource, but the eight mile limit precluded consideration of the full scenic impact. Examples include the Saddleback Ridge project as viewed from Mount Blue (only 5 of the project’s 12 turbines were considered during permitting) and the proposed but withdrawn Highlands Wind project (only 6 of 48 turbines would have been considered. These recommendations do not go as far as the one made in the 2012 GOEIS report, which would require consideration of visual impacts for all SRSNS within 15 miles of a project. Our analysis indicates that this is unlikely to be necessary in many cases. However, in certain situations the failure to consider scenic impacts beyond eight miles is likely to reduce public confidence in the permitting process. Adoption of these recommendations would increase the credibility of the permitting process, increase confidence in the ability of Maine’s laws to adequately consider impacts to the state’s most significant scenic resources, and help to more fully realize the Governor’s Task Force’s objective to ensure that wind power development does not degrade Maine’s quality of place.

26 Highland Plantation, the site of the proposed Highland Wind project, was removed from the EPA through the petition process. However, the plantation subsequently assumed local land use regulatory authority. The plantation was thus returned to the EPA and remains available for development.

REFERENCES American Wind Energy Association. 2019. State Facts Sheets. https://www.awea.org/resources/fact-sheets/state-facts-sheets. Appalachian Mountain Club. 2014. Bingham Wind Agreement Provides for Appalachian Trail Conservation (settlement agreement public statement). https://www.outdoors.org/wp- content/uploads/2017/06/bingham-wind-agreement.pdf#search=bingham. Bangor Daily News. 2017. Wind power foes: Don’t ruin Maine’s beauty to feed ‘green energy’ demands. Bangor Daily News, April 15, 2017. https://bangordailynews.com/2017/04/05/the- point/hikers-wind-foes-out-of-state-energy-demands-shouldnt-mar-maine-scenery/. Bishop, I.D. 2002. Determination of thresholds of visual impact: the case of wind turbines. Environment and Planning B: Planning and Design 29:707-718. Governor’s Office of Energy Independence and Security. 2012. Maine Wind Energy Development Assessment: Report and Recommendations. OEIS, Augusta, ME. Governor’s Task Force on Wind Power Development. 2008. Report of the Governor’s Task Force on Wind Power Development: Finding Common Ground for a Common Purpose. GTFWPD, Augusta, ME. Gallo, S. 2013. Wind Power and Wildlife in Maine: A State-wide Geographic Analysis of High-Value Wildlife Resources and Wind Power Classes. Maine Audubon Society, Falmouth, ME. Haggerty, S. and S. Stockwell. 2019. Renewable Energy & Wildlife in Maine: Avoiding, Minimizing & Mitigating Impacts to Wildlife and Habitat from Solar, Wind, and Transmission Facilities. Maine Audubon Society, Falmouth, ME. Land Use Planning Commission. 2017. Windpower Expedited Area Petitions website. https://www.maine.gov/dacf/lupc/projects/wind_expedited_area/wind_expedited.shtml. Maine Department of Agriculture, Conservation and Forestry, Land Use Planning Commission, Augusta, ME. Land Use Regulation Commission. 2008a. Commission Decision in the Matter of Maine Mountain Power LLC. Maine Department of Conservation, Land Use Regulation Commission, Augusta, ME. Land Use Regulation Commission. 2008b. Commission Decision in the Matter of TransCanada Maine Wind Development Inc. Maine Department of Conservation, Land Use Regulation Commission, Augusta, ME. Land Use Regulation Commission. 2011. Commission Decision in the Matter of Blue Sky East LLC. Maine Department of Conservation, Land Use Regulation Commission, Augusta, ME. Maine Board of Environmental Protection. 2013a. Board Order in the Matter of Saddleback Ridge Wind LLC. Maine Board of Environmental Protection, Augusta, ME. Maine Board of Environmental Protection. 2013b. Board Order in the Matter of Passadumkeag Windpark LLC. Maine Board of Environmental Protection, Augusta, ME. Maine Department of Environmental Protection. 2009. Department Order in the Matter of Record Hill Wind LLC. Maine Department of Environmental Protection, Augusta, ME. Maine Department of Environmental Protection. 2012. Department Order in the Matter of Evergreen Wind Power II. Maine Department of Environmental Protection, Augusta, ME.

Maine Department of Environmental Protection. 2013a. Department Order in the Matter of Hancock Wind LLC. Maine Department of Environmental Protection, Augusta, ME. Maine Department of Environmental Protection. 2013b. Department Order in the Matter of Champlain Wind LLC. Maine Department of Environmental Protection, Augusta, ME. Maine Department of Environmental Protection. 2014. Department Order in the Matter of Blue Sky West LLC. Maine Department of Environmental Protection, Augusta, ME. Maine Department of Environmental Protection. 2019. Weaver Wind project page. https://www.maine.gov/dep/land/projects/weaver-wind/index.html. National Academy of Sciences. 2007. Environmental Impacts of Wind-energy Projects. National Academy of Sciences National Research Council, Washington, DC. Scottish Natural Heritage. 2012. Assessing the Cumulative Impact of Onshore Wind Energy Developments. Scottish Natural Heritage, Inverness, Scotland, UK. Scottish Natural Heritage. 2017. Siting and Designing Wind Farms in the Landscape, Version 3a. Scottish Natural Heritage, Inverness, Scotland, UK. Sullivan, R.G, L.B. Kirchler, T. Lahti, S. Roché, K. Beckman, B. Cantwell and P. Richmond. 2012. Wind Turbine Visibility and Visual Impact Threshold Distances in Western Landscapes. National Association of Environmental Professionals 37th Annual Conference, Portland, OR. Sullivan, R.G., L.B. Kirchler, J. Cothren and S.L. Winters. 2013. Offshore wind turbine visibility and visual impact threshold distances. Environmental Practice 15:33–49. UL LLC. 2019. Wind Resource Grid website. https://dashboards.awstruepower.com/products/wrg. U.S. Department of Energy. 2019. Office of Energy Efficiency and Renewable Energy WINDExchange web site. https://windexchange.energy.gov/maps-data/321. U.S. Energy Information Administration. 2019. Electricity: detailed state data. https://www.eia.gov/electricity/data/state/. U.S. Fish & Wildlife Service. 2019. Federal Aviation Administration (FAA) Wind Turbine Location Data. https://www.fws.gov/southwest/es/Energy_Wind_FAA.html. Vissering, J. 2011. A Visual Impact Assessment Process for Wind Energy Projects. Clean Energy States Alliance, Montpelier, VT.

Figure 6. Viable wind resource at a hub height of 100 meters: (a) statewide, (b) within the expedited permitting area excluding conservation land.

Figure 7. Viable wind resource at a hub height of 140 meters: (a) statewide, (b) within the expedited permitting area excluding conservation land.

Figure 8. High Value Scenic Resources with 8 miles (left) and 15 miles (right) of the Record Hill wind project.

Figure 9a. Hypothetical project on Deer Mountain. Figure 9b. Hypothetical project on Misery Ridge.

Figure 9c. Hypothetical project on Stetson Mountain. Figure 9d. Hypothetical project on Tracy Mountain

Figure 9e. Hypothetical project on Weatherbee Hill.

Figure 10a. Bare-ground viewsheds of a hypothetical Deer Mountain wind power project at 8 miles (left) and 15 miles (right) (100 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 10b. Bare-ground viewsheds of a hypothetical Deer Mountain wind power project at 8 miles (left) and 15 miles (right) (140 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 11a. Bare-ground viewsheds of a hypothetical Misery Ridge wind power project at 8 miles (left) and 15 miles (right) (100 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 11b. Bare-ground viewsheds of a hypothetical Misery Ridge wind power project at 8 miles (left) and 15 miles (right) (140 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 12a. Bare-ground viewsheds of a hypothetical Stetson Mountain wind power project at 8 miles (left) and 15 miles (right) (100 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 12b. Bare-ground viewsheds of a hypothetical Stetson Mountain wind power project at 8 miles (left) and 15 miles (right) (140 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 13a. Bare-ground viewsheds of a hypothetical Tracy Mountain wind power project at 8 miles (left) and 15 miles (right) (100 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 13b. Bare-ground viewsheds of a hypothetical Tracy Mountain wind power project at 8 miles (left) and 15 miles (right) (140 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 14a. Bare-ground viewsheds of a hypothetical Weatherbee Hill wind power project at 8 miles (left) and 15 miles (right) (100 meter hub height). (VIA stands for Visual Impact Assessment.)

Figure 14b. Bare-ground viewsheds of a hypothetical Weatherbee Hill wind power project at 8 miles (left) and 15 miles (right) (140 meter hub height). (VIA stands for Visual Impact Assessment.)

APPENDIX A: Determination of viable wind resource The extent of the viable wind resource was developed jointly by Maine Audubon Society and AMC using procedures adapted from an earlier MAS study (Gallo 2013). At that time wind resources were categorized according to wind power class, which is a way of quantifying the strength of the wind at a particular height using wind power density (how much energy, in watts per square meter, is contained in the wind) on a scale of 1 to 7. The 2013 MAS study used data on wind power class at a height of 80 meters. The industry is moving away from the use of wind power class, and now wind resource data is provided as average annual wind speed in meters per second (m/s). However, the viable wind speeds determined in this analysis roughly correspond to the wind speeds associated with the viable wind power classes used in the 2013 analysis. In order to determine the minimum viable wind speed at both 100 and 140 meters above ground, we examined the spatial relationship between existing and proposed wind turbines and the wind resource at 100 meters as follows:  The original AWS Truepower data was converted from its native floating point raster format to an integer raster representing 0.5 m/s classes (e.g. 6.0 – 6.5 m/s). Areas with wind speed less than 4.5 m/s were eliminated. This raster was then converted to an ArcGIS shapefile.  In order to provide an appropriate comparison with the wind data at 100 meters, we extracted all turbines with a heights of 475 to 525 feet (145 to 160 meters). Assuming a standard rotor diameter of 100 meters, these turbines would have hub heights of 95 to 110 meters. A total of 75 existing and 236 proposed turbines were identified with heights between 476 and 499 feet.  These turbines were overlaid on the wind resource data to determine the modeled wind speed for each turbine. Only one existing and 17 proposed turbines in this height range were located in areas with wind speed less than 6.5 m/s (Fig. A.1). Based on this we set the minimum viable wind speed at 6.5 m/s. In addition, based on an on-screen examination of the layout of the projects in relation to areas of different wind speed classes, we eliminated all separate polygons with wind speed less than 6.5 m/s that did not abut a polygon with wind speed of 7.0 m/s or greater. We also eliminated any isolated single pixel polygons (equal to four hectares or ten acres) that were more than 400 meters away from any other polygons. (This was based on MAS discussion with developers during the 2013 study.) Finally we eliminated all areas that Figure A.1. Distribution of existing and proposed turbines overlapped with open water. between 475 and 525 feet tall by wind speed.