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by JOHN STANGThe Daily Inter Lake
| June 23, 2008 1:00 AM

Waste land

Compost plant 'maxed out on sludge'

Day after day, sludge from Kalispell's sewage plant gets trucked to Olney.

Two to eight 15- to 20-ton truckloads a week - about 260 trips in 2007 - are hauled on the 35-mile drive to Glacier Gold in Olney.

The sludge has been separated from the plant's wastewater to trim the volume of microbes in the fluid to a level that the facility is legally allowed to handle.

At Glacier Gold, the sludge is mixed with bark and sawdust.

The concoction is then stored in big barnlike warehouses where the air flows are adjusted to heat and cool the muck - under a proprietary process (another way of saying "secret formula") - to kill off microbes and create Glacier Gold's compost.

But Glacier Gold has reached its capacity to accept Kalispell's sludge.

"We're about maxed out on sludge," Glacier Gold general manager David Larson said.

The company accepts about 6,000 cubic yards of sludge annually, mostly from Kalispell and the rest from Glacier National Park. State regulations say it cannot accept more.

Kalispell shipped as much as 5,200 cubic yards to Glacier Gold in 2007, according to city estimates

But Kalispell's sewage-treatment plant is expanding, with the likelihood of generating more sludge than Glacier Gold can accept.

Right now, the sewage plant is treating roughly 3 million gallons of sewage a day with the capacity to handle an average of 3.1 million gallons daily.

Plant expansion that will allow treatment of 5.4 million gallons a day is expected to be finished in early 2009.

A rule of thumb is that one new home creates 250 gallons of waste water a day.

That extrapolates to every 1,000 new homes producing 433 extra cubic yards of sludge a year at Kalispell's sewage treatment plant.

It is difficult to predict how fast that sludge production will grow along with new construction.

Forecasters can look at two figures:

. Kalispell has averaged 333 new homes built annually for the past six years. That average translates to the sewage plant accepting 83,350 extra gallons of waste water each day and producing 114 extra cubic yards of sludge a year.

. Developers have more than 6,000 new Kalispell homes on the drawing board for the next 12 to 20 years. That many new homes translates to the sewage plant accepting 1.5 million extra gallons of wastewater and producing almost 2,600 extra cubic yards of sludge.

This means the sewage plant eventually will have to find other places to take its sludge, plant manager Joni Emrick said.

Right now, the plant sends roughly one truckload a week to the Flathead County landfill. If the sludge volume increases, more loads might have to go to the landfill or other facilities might have to be located to accept the sludge, she said.

Glacier Gold was originally American Timber, a traditional sawmill operation founded in the 1920s.

As sawmills tried to squeeze every bit of use out of their logs, American Timber set up Glacier Gold on its Olney site in 1993 as a way to use its sawdust to make something valuable.

The roughly 6,000 annual cubic yards of sludge from Kalispell and Glacier National Park ends up as about 17,000 cubic yards of compost a year being sold as far away as 1,000 miles from Olney.

Most of American Timber's operations shut down in 2000, leaving only the compost and chip production lines. American Timber has bought big-beam and stud mills and is ready for the market to be right to crank up those operations.

Kalispell's sewage sludge is tested every three months in Billings for heavy metals.

"Our sludge from the Flathead Valley is extremely clean," Larson said.

Glacier Gold also has its compost tested for contaminants: A lab in Kellogg, Idaho, tests for heavy metals and the University of Montana tests the compost for E. Coli bacteria.

Larson said the company has never had a problem with its compost meeting federal and state standards.