MIDVALE — Once a desolate field, colored black from toxic tailings, today's Bingham Junction looks dramatically different than the eyesore of the past.

Grassy hills with an occasional sunflower patch now sit atop 350 acres of fresh soil, and Midvale city officials hope the site will become a popular mixed-use project for the blue-collar city.

Monday was a landmark day for the old Midvale Slag site, where lead and arsenic once permeated the soil and were often sent flying into the air by smelters that long occupied the area. State, city and environmental officials met on the land just west of the 7200 South freeway exit to celebrate its future.

The former Superfund site took 17 months and $17 million to clean up. The site was removed from the Environmental Protection Agency National Priorities list last month, a list it had been on since 1991.

The environmental overhaul was completed by ENTACT Inc., a Texas-based company. The process included removing the highly contaminated soil and burying slag with new dirt. On top of that, the EPA will continue to monitor construction on the site, including air and water quality.

"You could not walk on this property a year ago because it was not safe," Midvale Mayor JoAnn Seghini said. Seghini grew up in Midvale and remembers tasting the metal from the smelters in her mouth as a young girl. After serving 23 years in the city government and fighting to lose the city's smelter stigma, Seghini said Monday that she was floating.

"This day, after 23 years, it's a miracle it finally came to this point," she said.

The land constitutes 20 percent of Midvale and is one of the last pieces of undeveloped property in the city. It spans two toxic sites — Midvale Slag and Sharon Steel — and was a discouraging blight, Seghini said.

"This is the only place I can guarantee is clean. Any other lot you buy, who knows," Seghini said, laughing. "There's always the perception that it's not clean. I can guarantee you, working with EPA and UDEQ (Utah Department of Environmental Quality), it's very clean."

Right off the I-15 and I-215 freeways and barely 20 minutes from most Salt Lake County locations, city staff plan a fiber-optic wired development that will be a technology park.

"If we were to identify the epicenter of our population along the Wasatch front, it would be right where we sit today," Gov. Jon Huntsman Jr. said. "When you talk about a populated region like the Wasatch Front that is growing twice, three times the national average, and we're taking up virtually every single corner of land available in the Wasatch Valley, this kind of location becomes extremely important."