Not since the early settlers arrived in the Salt Lake Valley has there been so large a clean slate for development, Kennecott Land officials are fond of saying. And rarely has there been anywhere in the United States such a large-scale plan for tackling so huge a piece of undeveloped property.

All of Kennecott's land lies within 20 miles of downtown Salt Lake City. It runs along the Oquirrh Mountain foothills and all the way to the top of the mountains, in some places crossing over into Tooele County.

Of the 79,000 acres lying in Salt Lake County, 4,000 acres have already been planned as South Jordan's Daybreak community, Kennecott Land's first project in which 800 homes have already been built, an 85-acre lake is being filled and a school and community center serve more than 1,100 children and their families. When Daybreak is finished, the community will feature 13,000 homes .

Another 34,000 acres will remain untouched as open space, much of that lying on steep slopes along the mountain range.

The rest of Kennecott's land project — about 41,000 acres — will be developed, piece by piece, following the county's adoption first of the general principles of the plan and then of the specific land uses. Kennecott Land expects it will take about 75 years before all the development is complete. What will happen after Daybreak has yet to be announced.

While the land has been used for more than a century for mining, McMahon said only about 13,000 or 14,000 acres have ever actually been part of the mining footprint. The rest, he said, has been "effectively untouched."

Still, in 1999 Rio Tinto conducted the country's largest voluntary remediation work to clean up any residue.

McMahon said the first developments will be on that untouched land and that it will be many decades before any development begins on land used for mining or tailings.

The plan

Kennecott Land's current master plan for the development centers on a mass transit "spine" running from Daybreak in the south to a large urban development to the north, off I-80 north of Magna. The line would include light-rail spurs connecting to existing and planned lines throughout the valley.

Along the transit spine would be the bulk of the development — from small neighborhoods and grocery store developments to large urban developments packed with multifamily housing and 1 million square feet of commercial space.

Farther west, small, low-density foothill developments would pop up here and there, with the possibility of a skiing area near Soldier Flats in the top of the Oquirrhs.