Construction work is still going on at the site of the attacks
A US judge has dismissed a legal case claiming that the New York authorities denied proper burials to the victims of the attacks on 11 September 2001.
Relatives of World Trade Center victims claimed the city acted wrongly by sending debris that might have held remains to a rubbish dump.
The lawsuit asked for the debris to be removed to land that could be turned into a cemetery.
But the judge said the families had no claim to the removed material.
"Plaintiffs have no property right in an undifferentiated, unidentifiable mass of dirt that may or may not contain the remains of plaintiffs' loved ones," said district judge Alvin Hellerstein.
He said city officials had made "difficult and complicated" decisions about the debris, but concluded they had "acted responsibly" in bringing about a "swift and efficient recovery from the terrorists' attack".
He recommended the creation of a memorial and a nature reserve at the landfill site.
One of the lawyers for the relatives said he was "extremely disappointed" by the ruling.
"The 9/11 families sought to rectify an egregious wrong that occurred regarding the disposition of human remains," Norman Siegel said.
"We are not prepared to leave hundreds of human remains of 9/11 victims on top of a garbage dump as their final resting place."
No remains were found of more than 1,000 victims of the attacks on the World Trade Center.