Environmental Impact of the Big Cypress Swamp Jetport

The "Environmental Impact of the Big Cypress Swamp Jetport", unofficially known as the "Leopold Report" or the "Leopold-Marshall Report", was a report authored by hydrologist Luna Leopold of the United States Geological Service for the Department of the Interior and officially released on September 17, 1969. Arthur R. Marshall, formerly of the United States Fish and Wildlife Service, helped draft the report. It is considered the first ecological impact report in the state of Florida.

On June 2, 1969, Walter Hickel, Secretary of the Interior in the Nixon administration, created a select committee to conduct an inquiry into a proposed jetport for supersonic transport in what is now known as the Big Cypress National Preserve on the border of the Everglades National Park in Florida. The proposed Everglades Jetport would have had six runways for supersonic aircraft, making it the largest airport in the world at the time. Russell E. Train, then undersecretary of the Department of the Interior, appointed Luna Leopold of the USGS to direct the environmental impact assessment. Before the report was published, Wisconsin Senator Gaylord Nelson leaked key conclusions from the report in defense of the Everglades: "Either we stop the jetport at the present site, or we publicly admit that we are going to destroy the park."