The city released more than 170,000 pages of records Tuesday detailing its response to the Sept. 11, 2001, terror attacks, including documents related to air quality following the collapse of the World Trade Center.
Mayor Zohran Mamdani announced the release ahead of the 25th anniversary of the attacks, saying the records will provide insight into what city officials knew about the conditions in Lower Manhattan.
“These are documents that show what the city knew about the toxic air around Ground Zero, when they knew it and how they acted to limit liability,” Mamdani said.
The records include the “frequently referenced Harding Memo,” according to the Mamdani administration — records from 68 boxes that were not located until 2025 despite multiple Freedom of Information Law requests, and documents concerning 7 World Trade Center.
Law Department officials along with 9/11 Health Watch worked to include records that plaintiffs were looking for in the initial release, redacting only personally identifiable information and details that pose security risks to building safety.
The online portal will be updated regularly, according to city officials, as the city’s Law Department continues to review additional records.
The records release follows a yearslong effort by 9/11 survivors, family members and advocates to obtain documents concerning the city’s response to air quality concerns after the attacks.
It also follows a 28-part records request filed in 2023 that was repeatedly delayed under former Mayor Eric Adams.
According to the Centers for Disease Control and Prevention, tens of thousands of people have health conditions related to the air quality after the towers fell. In the last 25 years, more people have died from 9/11-related illnesses than those who died on the day of the attacks.
Mamdani said the records release is intended to provide greater transparency as the city marks 25 years since the attacks.
“As we mark 25 years, it is time for this painful chapter to end,” Mamdani said.