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Vantage to Pomona Heights Chapter 2 <br />230 kV Transmission Line Project FEIS Proposed Action and Alternatives <br /> PAGE 2-13 <br />Table 2-2 Overhead Design Characteristics of the Proposed Vantage-Pomona Heights 230 kV <br />Transmission Line Project <br />FEATURE DESIGN CHARACTERISTICS <br />Line Length 40.5 to 66.8 miles <br />Type of Structure H-frame wood poles-open terrain <br />Single wood or steel poles in agricultural, developed and constrained areas <br />Structure Height H-frame structures - 65 to 90 feet <br />Single poles - 70 to 110 feet <br />Average Span Length H-frame structures - 650 to 1,000 feet <br />Single poles - 400 to 700 feet <br />Number of Structures per Mile H-frame structures - 6 to 8 <br />Singles poles - 7 to 13 <br />ROW Width <br />H-frame structures - 125 to 150 feet <br />Single poles - 75 to 100 feet <br />Dead-end and angle structures-Additional ROW required for guys and anchors <br />(area determined by structure height and angle) <br />Land Disturbed (approximate): <br />Temporary <br />Structure Work Areas <br />(H-frame Structures) <br />(Single Poles) <br /> <br />Turn-Around Areas <br /> <br />Pulling and Tensioning Sites <br /> <br />Construction Yard/Staging Areas <br />(existing disturbed areas) <br /> <br />Permanent <br />Structure Base <br />H-frame <br />Single Pole <br />Steel Lattice <br />Work Pads <br />Access Roads <br /> <br /> <br /> <br /> <br />150 x 125 feet (18,750 sq. ft.) <br />150 x 80 feet (12,000 sq. ft.) <br /> <br />60 x 60 feet (3,600 sq. ft.) <br /> <br />125 x 400 feet (50,000 sq. ft.); Sites every 11,000 feet (2 miles) or less <br /> <br />5 acres; 3 yards required <br /> <br /> <br /> <br />20 inch diameter each pole = 40 inches <br />24 inches diameter <br />4 footings, 60 x 60 feet (3,600 sq. ft.) <br />30 x 40 feet (1,200 sq. ft.) <br />Minimum 14 feet wide up to 24 feet wide by length, depending upon terrain <br />Access Roads <br />Minimum 14 feet wide up to 24 feet wide by length, depending on terrain - <br />approximately 1.1 to 2.5 miles (depending on slope) of new road per mile of <br />transmission line where new road would be required. Existing roads would be <br />used whenever possible. <br />Voltage 230,000 volts alternating current <br />Circuit Configuration Single-circuit with 3 phases per structure <br />Conductor Size 1,272 kcmil (1.354 inch diameter) aluminum conductor steel reinforced <br />Ground Clearance of Conductor 28 feet minimum - up to 35 feet (typical) <br />minimum of 34 feet clearance for I-82 crossings <br />Structure/Pole foundations <br />Poles generally would be placed in augured holes and tamped. Foundations may <br />be required in rough terrain, uplift areas or large angles. <br />Single-circuit steel lattice structures for Columbia River crossing would require <br />steel reinforced concrete drilled piers. <br />* Note- Line length varies with Action Alternative.