A judge in Miami has refused to postpone her decision to dismantle the migrant detention center. This while the federal government is appealing her decision.
"Alligator Alcatraz" was quickly built two months ago on an abandoned airfield in a nature reserve next to the Everglades national park.
According to environmental groups and the Miccosukee tribe, the facility is a threat to protected plants and animals and sensitive wetlands.
Opponents want to stop further construction until federal environmental laws are followed.
US President Donald Trump visited the facility last month. He suggested that it could become a model for detention in the entire country.
A decision has already been made that the facility must be dismantled within 60 days to protect nature. All new admissions have also been stopped.