Mary Lee Hannell worked for The Port Authority of New York & New Jersey for over 20 years. This agency built the Twin Towers, and had its headquarters in the World Trade Center on the 67th floor. Mary Lee worked in the Human Resources Department and therefore knew many of the employees, including most of the 84 Port Authority employees who were killed. She survived the first attack on the World Trade Center in 1993 and then the second attack in 2001.