N.Y. Comp. Codes R. & Regs. tit. 21 § 1290.26
No person shall allow any garbage, debris or other waste materials (whether solid or liquid) to collect or accumulate at the World Trade Center and each person shall be responsible for the removal from the World Trade Center of all garbage, debris and other waste materials (whether solid or liquid) arising out of that person's operations or occupancy or use of space at the World Trade Center. All persons shall use extreme care when effecting removal of all such waste and in no event shall any person use for such purpose any facilities of the Port Authority without the prior consent in writing of the manager of the World Trade Center. All persons shall effect such removal only during such hours and by such means as are prescribed by the manager of the World Trade Center. No person shall use the water closets, wash bowls or other plumbing fixtures for any purposes other than those for which they were designed, and no person shall throw therein any improper articles or substances (whether liquid or solid) including without limitation thereto garbage, refuse, sweepings, rubbish, rags, ashes or litter. No person shall drop or throw anything out of the doors, windows or down the passageways or into any ventilating or elevator shaftway, stairwell or other openings. The cost of correcting any condition or repairing any damage resulting from misuse of fixtures or facilities or from other actions prohibited herein shall be borne by the persons who, or whose officers, employees, representatives, agents, contractors or invitees, have caused the same.
N.Y. Comp. Codes R. & Regs. Tit. 21 § 1290.26