Photo
A transfer trailer dumps a load on a tipper at Mallard Ridge.
A transfer trailer dumps a load on a tipper at Mallard Ridge.
Josh Osborne drives a compactor over the daily working face in cell 3A at Mallard Ridge in Delavan.
-- 743 acres
-- 90 acres of permitted landfill, of which 70 have been constructed
-- Current daily volume at about 1,300 tons per day
-- 634,360 tons received between 2008 and 2009
Ecological restoration and enhancement
-- 280 acres of restored prairie
-- 80 acres of restored savannah
-- 11 wetlands
-- 55 native species of plants installed
-- 200-acre controlled prairie burn annually
-- 2.5 miles of nature trails
-- 1.4 miles of protective turtle fencing
-- $90,000 annual cost to run Ecological Restoration and Enhancement Project
Mike Williams likes to think of himself as a protector of the environment.
He runs a place that combines hundreds of acres of restored prairie, savannah and wetlands, dozens of native species of plants and 200 acres of controlled prairie burned annually.
His domain also includes 2.5 miles of nature trails, observation decks, picnic areas and 1.4 miles of protective turtle fencing.
And it includes Walworth County’s largest disposal site, Mallard Ridge in Darien Township.
Surprised?
You shouldn’t be.
Aside from collecting most of Walworth County’s trash, Mallard Ridge spends $90,000 annually to run its Ecological Restoration and Enhancement Project.
The site also hosts a project to electronically monitor and protect Blanding’s turtles, a rare species found in the area, along with Queen snakes and Massasagua rattlesnakes.
Not everything is trash
One effort to renew and reutilize trash is the landfill’s gas-to-energy facility that has been operating since October 1996, said Williams, Mallard Ridge’s general manager.
Landfill gas released by trash is sucked by a series of pipes into three large diesel engines, each producing about 800 kilowatts per day.
That’s enough energy to feed all of Mallard Ridge and more than 1,300 homes and businesses in the area, and the process saves the equivalent of 22,147 barrels of oil per year.
It also saves neighbors from the trash smell typical of landfills. The series of pipes and valves distributed throughout the property is normally enough to take the odor away, Williams said.
Sometimes, though, neighbors complain, and Mallard Ridge workers look into when the odor was strong and what the wind was like to determine which valves to adjust, he said.
The workers pay close attention to valves because suction units must be balanced so they don’t suck too much gas and risk bringing in oxygen, which could combust in the gas-to-energy engines.
“It’s a constant balance,” Williams said.
How does the whole thing work?
Mallard Ridge has 14 employees and occasionally hires more temporary workers to pick up paper or reorganize trash.
To protect the environment, engineers analyze the area and determine how deep the landfill is allowed to go and not affect ground water.
Once the hole is dug, the bottom is layered with compacted clay liner, synthetic liner and a drainage layer. The idea is to let water from the trash come through and be drained to an outlet without reaching ground water, Williams said.
After the trash holes—or cells—are full, they are covered with granular drainage material, a moisture barrier layer and a final clay cap with vegetation.
When Williams and his staff are done with a part of the property, it is hard to tell there is any trash there. The area is covered with grass and looks like a regular hill. The only giveaway is the suction valves scattered on the property.
“We have one of the best-looking landfills here,” he said. “We’re proud of not just looking like a landfill.”
Mallard Ridge’s most recent addition is the 48-acre southern expansion, which is expected to last for the next 12 years after ARC Disposal and Recycling of Chicago pulled out its business in early June.
The company was responsible for about half of the trash deposited at the landfill—about 1,100 tons of waste per day—and not having that business has nearly doubled Mallard Ridge’s expected site life.
Williams said ARC stopped using the landfill after state legislators proposed an increase in landfill tipping fees. The $7.10-per ton increase is part of an effort to offset the state budget shortfall and is included in the version of the state budget that heads to Gov. Jim Doyle’s desk for approval this week.
The loss in business could cost the town of Darien nearly $700,000 per year.
Looking ahead
Williams and his crew are responsible for monitoring gas levels 40 years after they are done using the property. Gas production peaks at 20 years and wears off until it becomes non-existent at about 40 years, he said.
Other landfills throughout the nation have created public areas and even golf courses on top of closed landfills, Williams said.
“But you can’t get hog-wild on what you do,” he added.
Williams is talking with town of Darien officials about how to make the land more available for public use.
Mallard Ridge currently maintains 280 acres of restored prairie, 80 acres of restored savannah and 11 wetlands, along with 2.5 miles of nature trails.
The hope is to protect Mallard Ridge equipment from the public but leave the property off of Highway 11 available to the community around the clock.
“Fifty years ago, people would just dig a hole on the ground and throw in trash,” Williams said.
“But this is for our kids’ kids.”