8-2-4-2: AIRPORTS:
Airports shall be permitted in the agricultural (A) and industrial (I) districts, subject to administrative review that demonstrates that the following provisions are met:
   A.   Minimum Site Area: The minimum site area for this use shall be three hundred (300) acres.
   B.   Noise Impact: All airport development shall be submitted with a noise impact assessment. The assessment shall identify the initial and twenty (20) year projected day-night level (DNL) noise contour lines beginning with 50 DNL and proceeding to 75 DNL. The following standards shall be met:
      1.   Airport Boundary: The twenty (20) year, 65 DNL line shall lie completely within airport property or land that has been granted a noise easement.
      2.   55 DNL Limited Development Area:
         a.   No new residential development shall be permitted within the 55 DNL line. If for some reason a new residential use must be permitted, the building shall have insulation and windows that limit aircraft noise within the building to 50 DNL. The applicant shall demonstrate that there is no residentially zoned land in the 55 DNL area or that noise easements have been granted to the airport.
         b.   Existing residential uses shall have five (5) years to remodel to provide insulation meeting the standards in subsection B2a of this section.
         c.   If the 55 DNL area expands, a zoning and land use plan for all land within the 55 DNL noise contour shall be submitted. This plan shall indicate the feasibility of restricting such land to nonresidential uses. Airport approval shall be based on the ability to minimize noise intrusion into existing residential areas and to prohibit new residential development that would hinder future airport expansion.
         d.   Once established, the county shall require all rezonings or development approvals that would permit residential use within the 55 DNL noise contour to record the noise contours on the property. In addition, all developments and all individual lot surveys shall show the noise contours, with an accompanying warning indicating the county will not restrain future airport growth because of residential development inside the 55 DNL noise contour. (Ord. 10-001, 1-12-2010)