A mound of decaying trash at the Fresh Kills Landfill will be home to a memorial to World Trade Center victims. That much, we know. After that, it's anyone's guess what will be done with Staten Island's mothballed garbage dump -- and I say that even after getting a sneak peak at six competing plans to convert it from one of the nation's most notorious dumps into one of the world's largest urban parks. The six finalists in the Municipal Art Society's design competition "Fresh Kills: Landfill to Landscape" were unveiled Wednesday night at the Staten Island Institute for Arts and Sciences. The gala opening drew a mix of Manhattan's hip urban design crowd with their rimless eyeglasses, trendy, East Village clothes and impenetrable architectural jargon and Staten Island community leaders with their aviator frames, sensible brown suits and hopes that the plans will include mundane, but much-needed, resources as ballfields, roadway improvements and community centers. "I'll like the idea of making that area beautiful again, but it's got to have plenty of recreational space, too," said Russ Nicholson, who, at 71, is on every local board, advisory committee and community group ("Retirement stinks!" he explained). "People gotta live!" Nicholson liked a few things he saw on Wednesday night, but, mostly, he was overwhelmed by pretentiousness. I was, too. Often, a bad idea can look good "on paper." Well, in a design competition, even the best ideas can look lousy on paper. For instance, one design, pompously called "Lifescape," presented a series of "threads, islands and mats" that combine to form "an expansive green matrix of infinite horizons and newly connected ecosystems." Whatever. Perhaps it would've made more sense if the diagram looked more like a park and less like a Pollock. Another finalist broke up the site into five "seeds": "Experimental Field," "Material Datum," "Depositional Edge," "Tectonic Zone," and "Event Surface." I would tell you what the designers envisioned but, frankly, I don't have the slightest idea...except that it involves trees. Even professional architecture people were flummoxed by the vague schematics and self-important explication. "It's typical pretentiousness," said Philip Nobel, a critic for Metropolis and ArtForum. "These designers are just building a wall of attitude between their actual ideas -- whatever they are -- and the public." That's not to say there weren't good ideas buried among all the "network of transects," "vertical zonation of species" and "eco-spheres" to create a new city landmark two-and-one-half times the size of Central Park. One design, called "rePark," envisions an outdoor movie theater, equestrian trails, gyms, ballfields, a memorial forest, a golf course, a waterpark made out of reused garbage barges and a five-kilometer picnic table made out of recycled laundry detergent bottles. Another scheme, called Fresh Kills Parkland, has many of those amenities, plus a nifty meadow that would focus the eyes towards Lower Manhattan. On Saturday, all six finalists will present their designs at the Richmond County Clerk's office. A jury will select the winner, who will then spend the next 35 years galvanizing public support, wrangling for permits, finagling for budget allocations and, if we're all lucky, building the damn thing. Saturday's session is open to the public, so expect a room packed with Staten Islanders who have been waiting 40 years for someone to plant oaks instead of offal at Fresh Kills. The voice of the people won't count in the voting, but don't expect this silent majority to remain quiet. "We want people to have strong opinions," said Ellen Ryan of the Municipal Art Society. "And we certainly won't stop them from booing or cheering." You heard the lady. --30-- email: gershny@yahoo.com