Papers filed yesterday by family members of 9/11 victims who want the city to separate tons of debris on Staten Island to search for human remains include a letter in which the city medical examiner says he is almost certain some remains are present in the landfill, and an affidavit from a recycling supervisor who recalls watching debris being carted away to pave roads and fill potholes.

The supervisor, Eric Beck, said some finely sifted debris, which could have contained the cremated remains of human victims of the terrorist attack on the World Trade Center, were carted away to be used for paving and filling while he worked for a private contractor at the Fresh Kills landfill from October 2001 through July 2002, according to the court papers.

Mr. Beck, a senior supervisor for Taylor Recycling Facility, which used sophisticated machinery to sift debris, made the assertion in a sworn statement that is part of a lawsuit filed in Federal District Court in Manhattan by family members of 9/11 victims.

The family members are trying to force the city to separate many thousands of tons of debris that they believe still includes body parts and other human remains from the landfill, and to create a formal burial place for them.