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The outer surface, shown on Toronto/Lester B. Pearson International Airport Zoning Plan No. 21-005 94-138, Sheets 13, 14, 15, 20, 21, 22, 23, 30, 31, 32, 33, 40, 41, 42, 43, 48, 49 and 50 dated July 31, 1995, 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 an imaginary plane located at 9 m above the surface of the ground.
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