- Associated Press - Friday, March 10, 2017

BEND, Ore. (AP) - Although OSU-Cascades hasn’t acquired the old Deschutes County landfill yet, it has a cleanup and restoration plan so it can build facilities, parking lots, sports fields and more.

The university plans to use cleaned material from the 76-acre landfill to partially fill an adjacent 46-acre former pumice mine it bought a year ago. Using material from the landfill will eliminate the need to have fill delivered from elsewhere and will prepare both properties - the pumice mine and the landfill - for construction of the university’s expanding campus.

The old landfill, located in southwest Bend near the university’s existing 10-acre campus, stopped taking waste in the mid-‘90s. It is separate from Knott Landfill in northeast Bend and is also a different type of landfill. While Knott is a municipal waste landfill, filled with trash from curbside bins, the old county landfill in southwest Bend took waste from construction projects and wood mills.

A lot of the waste in the old demolition landfill is sawdust and logs from the old mills, plus items such as roof shingles, siding, concrete pieces and tires.

The demolition landfill has been covered with dirt fill for years. On the surface, it looks mostly like soil and sagebrush. It’s what is several feet underground - a couple decades worth of demolition waste - that needs to be cleaned up or removed entirely.

OSU-Cascades has a nonbinding letter of intention with Deschutes County to acquire the old landfill. The letter states that if the cost to clean up and restore the land is more than the land’s worth, the county would sell the property to the university for $1. Since the land has been appraised at $25.5 million and the estimated cost of cleanup is $48.7 million, it’s expected the cost will be just $1.

OSU-Cascades hired Maul Foster & Alongi, a Portland-based environmental engineering firm, to complete a study on the old demolition landfill and come up with a strategy to clean up and restore the land so the university can build on it.

Because OSU-Cascades is focused on sustainability at all levels - from encouraging students and staff to walk or bike to school to the design of its buildings - the strategy for cleanup has an environmental bent. The engineering consultants’ plan suggests using cleaned material from the landfill to partially fill the former pumice mine where it also plans to build part of its campus. OSU-Cascades bought that property in January 2016.

The engineering consultants estimate 29,600 truck trips could be eliminated if the project uses fill from the old landfill in the pumice mine, according to a release on the cleanup strategy the university sent Thursday.

About half of the old landfill could support structures, while the other half could be used for areas such as ballfields, parking lots and plots for solar panels.

The old landfill has three distinct areas, or “cells,” Kelly Sparks, associate vice president for finance and strategic planning at OSU-Cascades, said Thursday. The cells are divided by age, use and fill materials.

In the engineering consultants’ plan, two of those cells would be dug up, and the material would be sorted and processed to either be reused on site or taken to another landfill. Reused material would help fill the former pumice mine and fill the third cell.

The university may not acquire the landfill from the county until around June, according to Sparks. While university staff thought the acquisition might happen as soon as this month, that timeline has been extended. The county and university are still discussing their agreement on the acquisition, and the next Oregon State University board meeting won’t take place until June. The board needs to vote in favor of acquiring the land.

Only after the acquisition agreement is finalized, can the university board approve acquiring the land and the state allocate money to spend on cleanup, according to Sparks. Preparing the former pumice mine and demolition landfill will take years, Sparks said.

The cleanup and restoration of the properties could start as soon as 2018, and construction could start as soon as 2020, Sparks said. Work on the former pumice mine and the demolition landfill will go on at the same time. The university’s second academic building, which will be located in the former pumice mine, could be built by fall 2021.

Expansion of the campus will allow the university to achieve its goal of serving 3,000 to 5,000 students. OSU-Cascades has about 1,100 students currently enrolled, including those dual-enrolled at Central Oregon Community College. The existing 10-acre campus has a capacity of 1,890 students, which the university expects it will reach by 2020, Sparks said.

“This land is a blight right now,” Sparks said Thursday. “It’s not being used to its full potential.”

Sparks is excited for the university’s opportunity to reclaim the land and use it to serve the community, adding “the regional benefit is significant.” The university has been crafting two plans: a 56-acre plan if the university has only its existing properties, the 10-acre campus and the 46-acre pumice mine, and a 128-acre plan, if it acquires the landfill, too.

Stacy Frost, a senior engineer at Maul Foster & Alongi, said the environmental engineering firm completed its study on the demolition landfill in the end of November. The firm evaluated the county’s past reports and studies before doing its own work, which included taking soil samples and methane gas samples from underground.

In its study, the environmental engineering firm recommends the university remove waste from cells 1 and 2, which would get rid of the methane gas as well. But methane gas is not a concern at the demolition landfill, the study found. Methane becomes a concern in heavy concentration in closed spaces.

The main issue at the demolition landfill is the land’s potential to settle as waste decomposes. The topography of the ground will sink in spots, Frost said.

“If you have a building on top of that, foundations could shift, utilities could get sheared,” Frost said.

That’s why the university will put parking lots, ballfields and open green spaces on the areas susceptible to shifting. If shifting were to occur under a parking lot, for example, that spot could be repaved.

Compared to a municipal landfill, like Knott, the demolition landfill has a lot fewer environmental concerns, Frost said.

“Typically with a municipal solid waste landfill, you’re concerned about stormwater or groundwater reaching the waste and creating a nasty runoff,” Frost said. “We have none of that with this site. Groundwater is more than 250 feet deep, and the type of waste is different.”

Frost said different kinds of waste are in each cell, depending on what was going on in Bend at the time. Cell 1 was the first area to be filled at the landfill, which opened in the 1970s, when mills were still booming. It has the most wood waste. Pyrolysis, a kind of underground burning, is still occurring there about 50 to 80 feet underground, Frost said, but it will end when the waste is removed.

For the university to build on an old landfill isn’t unthinkable, according to Frost.

“We’ve done this type of project for other clients,” he said. “This is not the first time it’s been done in the United States or even in the Northwest, so it’s nothing new.”

Maul Foster & Alongi worked on a project to build an $8 million sports complex in Astoria on what used to be a municipal landfill. The cleanup and restoration OSU-Cascades plans to do at the old demolition landfill once it acquires it would take place over a decade, Frost pointed out.

“So through that time, as new innovative approaches come up, they can use those,” Frost said.

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Information from: The Bulletin, https://www.bendbulletin.com

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