SANTA CLARA – One of the problems Jack Hill, the project executive for the 49ers' new $1.2 billion stadium, faces is how to transport 2,000 tons of dirt and topsoil 150 feet in the air.

"The soil's wet, it's heavy, and we have to get it fairly high off the field," he said this week.

It's a unique challenge for Hill, who most recently worked on the Cowboys' new stadium, and that's the point.

The dirt is intended for what the 49ers hope will be the signature feature of the venue, a 27,000-square-foot, energy-saving roof that will support a garden of native plants, which in turn will soak up rainwater and provide insulation for the tower of luxury suites it sits atop.

The roof will be the first of its kind in the NFL, and CEO Jed York wants it to be the 49ers' version of the Green Monster at Boston's Fenway Park or the B&O Warehouse at Baltimore's Camden Yards.

"There aren't that many iconic ideas in football stadiums," York said. "It symbolizes what we're doing in that it combines energy efficiency and technology and the fan experience. And it's elegant and classy. That's the overall vision of the stadium."

York and the 49ers broke ground on the project Thursday. On hand for the ceremony was one former 49ers coach, George Seifert, who as a teenager worked as an usher at old Kezar Stadium, and the current one, Jim Harbaugh, who told the assembled crowd that the 49ers were building a "great football cathedral."

At the end of the ceremony, York and others took golden shovels to a patch of earth that marks the center of where the stadium will be built.

The 68,500-seat facility is scheduled to open for the 2014 season, and the 49ers hope it will host 2016's Super Bowl L, the next Super Bowl to be awarded.

The concept for the yet-to-be- named stadium is twofold. York wants it to be the most technologically advanced venue in the league and the greenest venue in sports.

Baseball facilities have led the way in sustainable design with ballparks in Washington, D.C., Minnesota and, most recently, Miami, all attaining silver status in the Leadership in Energy and Environmental (LEED) rating system.

That system, developed by the U.S. Green Building Council, is a green-architecture scorecard that awards points based on design, construction and operation of buildings.

The 49ers are aiming for LEED gold status, and the team hired a consultant, Brightworks, to help reach that goal.

Among the other green components of the stadium:

• It will have the most advanced plumbing fixtures and will use non-potable water for irrigation and for flushing in the restrooms. Brightworks' Heath Blount estimated that water efficiency would be at least 45 percent better than at Candlestick Park.

• There will be at least 20,000 square feet of solar panels, including on the roof and perhaps the parking lots. For most of the year, the stadium will add power to the grid.

• It will have a ground-source heat pump, which uses the earth's surface as a heat source in the winter and as a heat sink in the summer. Most of the stadium will be open to take advantage of Santa Clara's mild weather. Enclosed areas like luxury suites will have fixtures that shut off mechanical cooling and heating when windows are opened.

• It will be built with regional and recycled materials whenever possible. The woodwork in the luxury suites, for example, will be made largely from fast-growing and sustainable bamboo.

• There will be bicycle parking, exclusive parking for car poolers and alternative-fuel vehicles, and a charging station for electric cars.

Ihab Elzeyadi, an architecture professor at the University of Oregon, commended the 49ers for being energy-conscious with a type of building – a sports stadium – that typically uses huge amounts of energy.

But he wished there was more innovation in the main part of the structure, such as placing photovoltaic cells on the outside of the building.

The green roof is a nice concept, he said, but at 27,000 square feet, it pales in comparison to the stadium as a whole, which is 1.85 million square feet. The heating and cooling impact of the roof, he said, will be minimal.

"They'll get a LEED credit for that," Elzeyadi said. "But getting LEED credits doesn't mean that you're doing something important for the environment."

Still, he acknowledged that the symbolic value, especially when it's done by the ultra-popular NFL, could outstrip the practical value.

"I'm excited the NFL is interested in this concept," he said. "It means we're having an effect."

York said he had one additional green concept in mind.

In the stadium's Hall of Fame, which has yet to be finalized, York envisions a section designed to teach fans how the facility's green components work and about sustainable design in general.

"It's important to show people the right way to do things," he said.

STADIUM COMPARISONS

– newsantaclarastadium.com

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