The project will involve construction of up to 200 turbines, generally arranged in rows along approximately 16 km (10 miles) of ridgeline comprising the Central Phase and Northern Phase (Figure 1). The turbine strings will have access roads and buried transmission lines along the roads. Where turbine strings are located in forests, the total area cleared to accommodate the access roads and transmission line will be approximately 11 m (35 feet) in width for the length of the turbine string. All forest clearing activities will be conducted over the winter period (November 15 to March 31).
A substation will be built adjacent to an existing transmission line in the project area. Therefore, no new overhead transmission line will be required for this project. There are several reclaimed strip mines in the project area, and preference will be given to locating turbines and associated facilities within those areas, if possible. The total area of ground disturbance for the entire project is expected to be less than 80 ha (200 acres).
The proposed turbines will likely range from 1.5 to 2.0 megawatts in size. These turbines typically have towers ranging from 65 to 70 m (213-230 feet) and associated rotor diameters ranging from 70.5 to 80 m (231-262 feet). Therefore, the space occupied by turbine blades typically ranges from 30 - 110 m (98-361 feet) above ground.
A literature review was conducted to summarize the relevant ecology of the federally endangered Virginia big-eared bat and Indiana bat. The literature review included habitat use, behavior that may be related to risk of turbine collision, and dispersal and migration patterns. Additional information on the ecology of these species was obtained by contacting experts on the biology of these species and local experts including University researchers and consultants. Available data on bat abundance and species composition in the area were summarized. The review also included a summary and analysis of available information on bat interactions with wind turbines.
To limit impacts to the Indiana bat, the USFWS has developed several guidelines. If more than 7 ha (17 acres) of forested lands are to be cleared, the USFWS will require one of two things. The first option is to conduct a mist net survey for the species between May 15 and August 15. The other option is to conduct the tree clearing between November 15 and March 31, when summer colonies are not present. If the development will result in clearing more than 17 acres, which this project will, the USFWS may request that a habitat survey be conducted within a 3.2-km (2-mile) radius prior to timber clearing to determine if the impacted area contains a significant amount of habitat relative to the surrounding landscape. The USFWS requested that NedPower conduct this analysis in a letter to Potesta & Associates dated August 30, 2002. In addition, the USFWS requested that bat habitat (i.e., presence of roosts and foraging habitat) along the turbine strings be determined in an email to WEST dated March 26, 2003. Therefore, a site visit was made to assess habitat suitability for bats at the proposed development areas and within a 3.2-km (2-mile) buffer of the areas. The general location of all proposed turbine strings was walked to examine habitat that will be directly impacted if the wind plant is built. The review included searching for potential Indiana bat roost trees, and describing habitat types along the general area of the proposed turbine strings (e.g., forest types, reclaimed mine lands, wetlands), as well as a description of other physical and biological habitat characteristics of the area. This review was used to assist with assessing the potential for foraging and/or roosting in the development area by Virginia big-eared and Indiana bats. The assessment also included an evaluation of the area as habitat for other bat species based on presence of roost sites (e.g., buildings, caves, bridges), forest types, topography, elevation and other habitat features. Areas within 3.2 km (2 miles) of the proposed turbine strings were surveyed by foot and vehicle to assess available habitat relative to the impact area.
The results of the habitat survey, information obtained on the ecology and habitat of the two endangered species, data on bat use of the area, and current information on bat interactions with wind turbines were synthesized to assess the potential risk of wind power development impacts to the endangered species. Based on this analysis, a determination of effect was made for both Virginia big-eared and Indiana bat.