New Jersey's window on the sky. Architects are turning 57 acres of marshy landfill into an experiment in environmental engineering and public art

DON SMITH looked down from the top of a 110-foot mound of New Jersey garbage covered by dirt and overgrown with thistle. Mr. Smith, a senior naturalist with the Hackensack Meadowlands Development Commission (HMDC), aimed his boot at a rotting piece of plywood and kicked it skyward. A handful of grasshoppers and a field mouse scattered into the underbrush.

Smith explained that the 57-acre landfill, closed three years ago, is already providing food and shelter for insects and small rodents, which in turn fall prey to the hawks and owls that winter in the surrounding meadows. ``Nature has the regenerative power to reclaim its own, even from our garbage,'' he said wryly.

Three decades of intermittent dumping have transformed this patch of New Jersey marshland into a 10 million-ton pile of garbage. When dumping ceased, the landfill evolved into a wildlife habitat of sorts.

Now the landfill - formerly the Kearny dump - is about to undergo one final, and some say unique, transfiguration. A team of landscape architects and the artist Nancy Holt are turning the mountain of garbage into a towering work of public art. HMDC officials say that landfills have been turned into amusement parks and golf courses, but never art.

The project, to be called ``Sky Mound,'' will transform the Kearny dump into an industrialized version of Stonehenge, a ``naked eye'' observatory with grassy hillocks, gravel paths, and steel structures arranged to align with the sun, moon, and stars on important astronomical dates of the year.

From the top of Sky Mound, solstices and equinoxes will be framed on the horizon by large earth mounds and tall steel posts. Like a giant croquet set, steel loops will line up with positions of the moon. The landscaping includes a large pond to collect rainwater, and a small moat encircling an island that will house a large cement sphere.

The mound, dubbed ``1-A'' by the development commission, juts into a skyline dotted with power lines, smokestacks, and refinery towers. It is the most visible of several dozen landfills in the Hackensack Meadowlands - 32 square miles of marshes and mud flats, office complexes, and condominiums. Once an ugly stretch of swamp and garbage, the Meadowlands now competes with New York City as an employer, providing jobs for about 90,000 people. It also receives about 40 percent of New Jersey's refuse.

Rising out of the Meadowlands' southeast corner, the future Sky Mound towers over the eastern spur of the New Jersey Turnpike, is backed by Amtrak and New Jersey Transit train tracks, and is shadowed by Newark Airport. In all, about 125 million commuters will view Sky Mound each year.

``Of all the landfills in the country, [Sky Mound] is the most visible,'' Ms. Holt said. ``If we're going to make a statement, this is the place to do it.''

HMDC officials and Holt hope Sky Mound will call the public's attention to the ``ancient'' problem of responsible garbage disposal, offer an aesthetic solution to reclaiming landfills, and help reverse the much-maligned image of this industrial gateway to New Jersey.

Most people see New Jersey only from the turnpike, where the greenery is painted on the sides of the highway,'' said Bob Grant, an HMDC spokesman. ``Sky Mound is part of the `can do' chauvinism sweeping New Jersey, which says that we can even create art from garbage.''

Holt was chosen for the project by the development commission, a nine-member, quasi-governmental agency formed in 1969 that oversees the development and protection of the 20,000-acre tract of wetlands that cuts through Bergen and Hudson Counties. Before the commission was formed, the land was used for indiscriminate and unregulated garbage dumping.

The artwork will not only dress up the ``1-A'' landfill, it will also function as a wildlife refuge and methane recovery system.

Anne Galli, director of environmental programs at the Meadowlands, said Sky Mound will probably be used as a flyway for Canada geese and other migrating birds. Drought-tolerant wild grasses and flowers that can survive on a thin layer of unirrigated, unfertilized soil are being tested to ensure that Sky Mound will become a breeding ground for the likes of cottontail rabbits and raccoons.

The artwork will be integrated into the methane recovery system, whereby the methane produced by decaying garbage will be sold to the Public Service Electric and Gas Company. Methane wells will be placed belowground, while four flares will burn continually on the upper slopes of the solar viewing area. GSF Energy Inc., which is leasing methane rights to the landfill, expects that its $10 million system will recover about 2 million cubic feet of gas daily.

All of the district's landfills were to have been closed five years ago, but 587 acres remain open because disposal plans have been delayed. They are to be closed by 1990.

Thomas Marturano, the director of the garbage processing operations at the Meadowlands, said the Sky Mound landfill will be sealed with a synthetic rubber liner and a thick layer of impervious clay spread on the sides and crown. An additional 18 inches of topsoil will be spread over the flat-topped, pyramid-shaped mound. Leachate, rainwater that seeps through the landfill, will be collected and treated as raw sewage.

Sky Mound will be the first landfill in the Meadowlands district to be closed ``with the best available technology,'' said Ms. Galli. It may become a model for salvaging and sealing other overflowing landfills.

HMDC environmental scientists are midway through a two-year study of 6,000 acres in the Meadowlands district, including the 1-A landfill, to ensure that the surrounding air and water are in compliance with standards set by the Federal Environmental Protection Agency. The EPA has not set safety standards for measuring hazards to plant and animal life, only standards for measuring threats to human health.

Galli said the studies so far show no violations of safety standards. Despite the absence of information on possible hazards to wildlife, environmentalists note an increase in species diversity throughout the Meadowlands district.

Once Sky Mound has been completed and possible health hazards scrutinized, the mound will be opened as a public park.

The project will be completed in two phases. The first phase, due to be finished by spring, will cost $11 million, regardless of whether the landfill becomes an artwork, said Mr. Marturano. This phase includes closing the landfill, installing the methane recovery system, building the ponds and paths, planting grass, and installing steel posts and wellheads in their stellar alignments.

During the second phase, said Holt, the radiating paths will be extended down to ground level, a bridge will be built across the pond, and spinning wind indicators will be placed around the mound. The estimated $500,000 needed to complete the second phase will come from grants and private donations. Funding will dictate the pace of construction. The New Jersey State Council on the Arts and the National Endowment for the Arts, citing the project's ``high visibility'' and ``unique alliance between engineering and art,'' have so far awarded more than $100,000. The development commission paid Holt $20,000 to design the project.

``City dwellers miss the sky,'' said Holt, who grew up in nearby Clifton, N.Y.

``Sky Mound will give them a chance to see the sunset from a different vantage point. And it will show how we can transform a despoiled landscape into something that people can appreciate - even though it's garbage.''