After 9/11, hundreds of undocumented workers joined the efforts to clean up Ground Zero. But twenty years later, they are suffering from major health issues caused by inhaling contaminated dust for months. Many are still fighting to obtain legal status. "It's an injustice," says Rubiela Arias, who worked in the area for over 8 months as a 37-year-old undocumented cleanup worker from Colombia. "I felt the need to help," she recalls. IMAGES AND SOUNDBITES ARRANGED IN SEQUENCES