Mike Fleming gave the blueprints, marked "Secure Document -- Confidential," to the New York Post.
Steve Coleman, a Port Authority of New York and New Jersey spokesman, said the agency has a 60-page guide to handling confidential documents, which does not include dumping them in trash cans in Greenwich Village. In fact, he said, they are not supposed to be taken out of the office.
"We don't tolerate stupidity," he said.
The apparent violation of procedures will be investigated by the agency's inspector general, and employees or contractors could face dismissal, Coleman said. But he told Newsday the Post still had the documents so the Port Authority is unsure exactly what ended up in the trash.
The Post said an expert described the blueprints as documents that would have been useful to terrorists planning another attack on Lower Manhattan.