The struggle between preservationists and rebuilding officials over ground zero escalated this week with a preliminary finding by the Lower Manhattan Development Corporation that the site's location, setting, feeling and association - not the structural remnants of the World Trade Center - render it historic.

Such a finding, were it to go unchanged and unchallenged, would make it far easier to rebuild, since it would essentially excuse federal and -state agencies from having to consider ways to mitigate potential destruction or alteration of the physical traces of the trade center, some of which might interfere with new construction. "The significance of the transcending events of Sept. 11 and the aftermath clearly does not depend on the presence of the original, or even the damaged, buildings and structures that portrayed the horror of that day," the corporation said in a document that was sent on Monday to participants in the federal historic preservation review process.

Though the document was not released publicly, a copy was made available to The New York Times. Kevin M. Rampe, the president of the corporation, said in an interview that the corporation had long been committed to preserving the "historic nature of the site, so future generations would never forget what happened here." He cited its insistence that nothing be built where the towers stood, that the slurry wall around the foundation remain exposed and that designs for the memorial allow access to the tower footprints. But he also said the site's historic nature derived in part from "the very fact that it has been a center of commerce," suggesting that commercial development was itself historically appropriate.

 Though the corporation determined on Feb. 6 that ground zero would be eligible for the National Register of Historic Places, it found three days later that reconstruction would have "no adverse effect" on the site's defining historical features, since they are largely intangible or general in nature. The finding is open for comment until March 15.

Critics of the process did not wait to express their displeasure. "Community leaders, historic preservationists and family members of those lost on 9/11 are being rushed through this process," Representatives Carolyn B. Maloney, Democrat of New York, and Christopher Shays, Republican of Connecticut, said yesterday in a letter to John L. Nau III, chairman of the federal Advisory Council on Historic Preservation, requesting his direct intervention in the review. The Coalition of 9/11 Families, which has focused on preservation at the site, raised the prospect of a lawsuit. Its preservation consultant, Joel I. Klein of John Milner Associates, said, "The L.M.D.C. made a predetermination of what their conclusions were going to be, what they needed the conclusions to be to expedite the approval of their project and then backed into their determination of eligibility and effect." Another preservation advocate, Robert Kornfeld Jr. of the Historic Districts Council, said the corporation "should do a more careful inventory and really look at the physical impact of all the different proposed actions and alternatives."

There is a fundamental philosophical debate between those who view the site more abstractly and those who find documentary value and emotional resonance in vestiges like the sawed-off column footings that defined the tower footprints, the shored-up slurry wall that formed the concrete bathtub in which the towers sat and even a section of the 95-year-old cast-iron Hudson & Manhattan Railroad tube.

That the corporation is inclined to the broader view was made clear in the document, which quoted an unnamed participant in the review process as saying, "A footprint can be something that is written on the psyche or in the soul and on the heart and not necessarily always in steel and cement and concrete." But the document also made a point of saying that redevelopment would expose the slurry wall and allow access to the truncated column remnants 70 feet below ground, though it is not yet clear what form access would take. "Does that mean somebody in overalls crawling on their hands and knees between the pipes?" Mr. Klein asked. "Anything short of full public access could be construed as an adverse effect."

As for the railroad tube, the document said part of it might be incorporated into the memorial center, which will contain salvaged artifacts. Many of these are kept by the Port Authority of New York and New Jersey in a hangar at Kennedy International Airport. They include some of the trade center's distinctive three-pronged columns, as well as ruined fire trucks, police cars and PATH trains. The private New York Landmarks Conservancy criticized the corporation for not including the dispersed objects in its assessment of historical significance. "Artifacts are every bit as important as tunnels, stairways and other physical remains at ground zero," said Peg Breen, the president of the conservancy.