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Earlier this week near Roosevelt, Washington, workers used a Skycrane helicopter to move and install large sections of 64 steel lattice towers on a section of the Bonneville Power Administration's 500-kilovolt McNary-John Day transmission line. The unique construction method allowed BPA to deal with challenging environmental conditions that made it safer for crews on the ground. The slope of the terrain along this span and soil conditions were not conducive to conventional construction methods that are appropriate for use on most of the other line segments. In addition, along this span conventional construction methods would have been more expensive.