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The outer surface, shown on Kenora Airport Zoning Plan No. 60-014 89-021, Sheets 6, 7, 8, 9, 10, 11, 12, 13 and 14, dated 4 December 1990, is an imaginary plane established at a constant elevation of 45 m above the elevation of the airport reference point, except that, where that plane is less than 9 m above the surface of the ground, the outer surface is located at 9 m above the surface of the ground.
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