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The outer surface, shown on Stratford Municipal Airport Zoning Plan No. 31-009 89-064, dated August 29, 1994, 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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