This article does not apply to any temporary seaplane landing site, ultralight vehicle flightpark, or to airports owned or operated by the United States. To the extent necessary, the department may exempt any other class of airports, pursuant to a reasonable classification or grouping, from any rule or requirement thereof, adopted pursuant to this article, if it finds that its application would be an undue burden on the class and is not required in the interest of public safety.

This section shall become operative on January 1, 1989.