Stateline Wind Project Wildlife Monitoring Final Report - WEST, Inc.

2.0 STUDY AREA AND PROJECT DESCRIPTION
The Stateline project area is in a semi-arid environment in the Columbia Basin Province.
Precipitation averages 25 to 38 centimeters annually, most of which falls from October through
March. Average annual air temperature is 10 to 12 degrees Celsius, and the average frost-free
period is 135 to 170 days. It is situated on privately-owned land zoned Exclusive Farm Use in
Umatilla County, Oregon and Primary Agriculture in Walla Walla County, Washington.
Elevation of the turbine strings ranges from approximately 274 m (900 ft) near turbine string
WSB to 533 m (1,750 ft) near the northern portion of the project (Figure 1). The land is
currently used for dryland (not irrigated) wheat production and cattle grazing. Wheat is
generally grown on a two-year rotation cycle - fields are rested (fallow) in alternation with crop
production (seeding, tilling, harvesting). Portions of the Stateline wind-leased lands that were
previously farmed have been placed in the Conservation Reserve Program (CRP) during the past
twenty years. Some fields have been taken out of the CRP through the various enrollment cycles
and these fields are now being grazed. Land cover of the Stateline landscape is a mosaic of large
wheat fields, native bunchgrass on deep and shallow soil, non-native mature CRP grassland
(crested wheatgrass), and narrow bands of sagebrush along major riparian corridors such as
Vansycle Canyon. Trees are very limited in the uplands. Scattered trees (black locust, Robinia
pseudoacacia) that were planted during early settlement can be found intermittently on dry sites;
native trees are limited to moist drainages and consist of willows (Salix spp.) and scattered
cottonwoods (Populus spp.). Wildlife habitat types in the wildlife monitoring study area (search
plots, etc.) are described elsewhere in this report.
The wind project consists of 454 Vestas V-47 wind turbines, rated at 660 kW each, with 273
turbines located in Washington and 181 turbines located in Oregon. Turbines are mounted on
50-m (165-ft) tubular steel towers (Figure 2). The rotor diameter of the three-bladed turbines is
47 m (154 ft), resulting in a rotor swept area (RSA) of 1735 m 2 . The maximum height above
ground to the top of the RSA is 72 m (242 ft). The minimum height above ground to the lower
portion of the RSA is 27 m (88 ft) (Figure 2). The V-47 wind turbines operate at wind speeds
from 10 to 90 kilometers per hour (kph) (8 to 56 miles per hour [mph]), at a relatively constant
(± 10%) speed of 28.5 revolutions per minute (rpm).
Approximately 140 of the wind turbines are lit with obstruction lighting. Turbines located at the
end of turbine strings are lit, and typically every fourth turbine within a string is also lit (Figure
1). Each lit turbine is equipped with Honeywell L-865 medium intensity red/white dual lighting,
with white strobe during the day (40 flashes per minute), and red flashing at night (20-40 flashes
per minute). The red lights also operate during dense fog conditions occurring during the
daylight periods.
3.0 METHODS
Detailed protocols have been developed for the monitoring studies and can be found in FPL
Energy et al. (2001), OEFSC (2001, 2002, and 2003), in Erickson et al. (2003a), and in the
Stateline Washington TAC meeting minutes and recommendations memos submitted to the
Washington permitting agency in 2002 and 2003. The methods are summarized in this report.
Stateline Monitoring Final Report 3
December 2004