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The outer surface, shown on St. Leonard Airport Zoning Plan Nos. S-2201-1 to S-2201-3 inclusive, S-2201-8 to S-2201-10 inclusive and S-2201-19 to S-2201-21 inclusive, dated January 23, 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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