During the weeks following the attacks of September 11, 2001, emergency workers concentrated on the recovery effort as firefighters continued to put out the many fires that burned at the World Trade Center site. After the recovery effort ended the task of clearing away rubble began; a process that lasted two years. 1.8 million tons of material was put on barges and carried to Fresh Kills on Staten Island. For 10 months the FBI conducted an in-depth investigation designed to recover human remains, personal items and any evidence directly related to the attack. At the height of the investigation...