For many years, the Ash Grove Cement plant in Durkee has been a linchpin of the local economy.
It has also been the hub of debates about jobs versus environmental regulation.
In 2012, Ash Grove Cement Company celebrates its 130th birthday. Ash Grove was founded in its namesake of Ash Grove, Mo., and its current headquarters are in Overland Park, Kan.
Besides the Durkee plant, Ash Grove owns seven others in the U.S. and a quarry in British Columbia, Canada. It’s the largest U.S.-owned cement company.
The plant in Durkee is the only cement plant in Oregon.
Its workforce of 109 includes residents from Baker City, Haines, and Huntington, as well as Ontario and the Idaho towns of Payette, Weiser and Fruitland.
The plant has an annual payroll of about $9 million and reports annual taxes of more than $790,000, according to company and county assessor figures.
Whenever things slow down at the plant, many feel the impact. Sluggish demand for concrete has led to temporary layoffs each of the past three winters.
Everything is on a large scale at the Durkee plant: from the rocks quarried to the machinery used, from the employment to the volume of cement.
“We’re running 3,100 tons of cement per day,” said plant manager Terry Kerby. “And if we’re selling out, we can run 3,300.”
In the manufacturing process, Kerby explained, limestone is mined on-site along with shale and clay.
The rocks are crushed and proportioned into a mix called raw feed.
Raw feed is transported to a huge tubular kiln and heated to around 2,800 degrees to produce clinker.
Clinker is then mixed with small amounts of gypsum and limestone and conveyed to the finish mill for final grinding into cement powder.
Voila! — Portland cement, which needs only water, sand and some type of aggregate, often gravel, to create the concrete for building foundations, freeways and sidewalks.
Kerby said the plant’s primary markets are in Boise, Portland and the Tri-Cities, Wash., where cement sales are tied to large-scale construction cycles.
Yet some point to another issue — the amount of mercury released into the air from cement plants.
The Durkee plant is located in an area rich with limestone, and the area’s volcanic activity left natural mercury deposits.
The cement manufacturing process was red-flagged by Jeremy Miller in a 2010 High Country News article, citing Durkee’s “vast amounts of mercury vapor.”
Miller wrote, “Mercury is also released from the coal burned as fuel in the kiln, but the amount is minuscule compared to what’s baked out of the limestone.”
High mercury concentrations were described in the Burnt River, which empties into Brownlee Reservoir near Huntington, about 15 miles southeast of Durkee.
Miller also described the impact on the Powder River: “the Powder River Watershed, 20 miles to the north, has also received heavy doses of Durkee mercury.
“The EPA estimates that of the 231 pounds of mercury deposited annually in the watershed, a full 150 pounds comes from Durkee.”
Ash Grove had been aware of its mercury emissions for some time, and Kerby said the company addressed the problem.
“We have 1,100 parts per million of mercury in our limestone, whereas in other places it may be five parts per million,” he said.
“And the EPA has put out a one-size-fits-all rule with the 2010 MACT (maximum available control technology).”
This rule would set standards for air pollutants from Portland cement manufacturers nationwide.
It has yet to take effect after delays. 2013 was the earlier target, though now it is Sept. 9, 2015.
More information is available at http://tinyurl.com/8cvs8sm.
“Mercury had never been controlled before,” Kerby said. “But we already entered into a mutual agreement order with the EPA.”
Outlining the mercury reduction efforts at Durkee, Kerby pointed out such technologies as raw material control, dust shuttling and powder activated carbon injection.
Brian Mannion of the Department of Environmental Quality’s Eastern Oregon Region explained the carbon injection method.
“Carbon particles stick to the mercury and then that is captured in a bag house, kind of like in a vacuum bag,” he said.
These bags of mixed carbon and mercury are then shipped and sold to a mercury waste company in Union Grove, Wis.
Mannion said Ash Grove self-reports mercury emissions from the Durkee plant daily.
“It’s about what society wants,” Kerby said. “We do it because it’s what we’ve been asked to do — there’s probably a fairer way than what the EPA is doing now, based on what the raw quarry level is.”
Environmentalists operate with a different bottom line.
“The Durkee plant has sought special exemptions based on the premise that they’re not doing anything unusual,” said Justin Hayes, program director of the Idaho Conservation League.
“That’s little comfort for those of us downwind,” Hayes said. “The mercury can precipitate and ultimately fall out of the air onto a land surface or water source.
“Bacteria interacts with mercury and bioaccumulates up the food chain. By the time my nine-year-old daughter catches a bass, we consume all the mercury it has consumed.”
According to publicly-available data from the EPA database, 879 pounds of mercury compounds were emitted in Baker County in 2010 and the entire amount came from Ash Grove Durkee.
About 78 percent of Oregon’s mercury compounds released came from the Durkee plant that year.
These numbers were confirmed by the EPA’s Air Program liaison to Oregon, Paul Koprowski, and Mark Bailey, DEQ Eastern Region air quality manager.
However, updated numbers appear to be much lower, attributable to mercury reduction technologies.
Kerby said, “the EPA rule limits mercury emissions to 55 pounds per million tons of clinker. Based on our average emissions, we will need to reduce 98 percent to meet the standard. Currently the plant has reduced emissions by over 95 percent.”
Doug Welch, environmental engineer with the Department of Environmental Quality office in Pendleton, confirmed these numbers.
The carbon-injection system was completed in July 2010 and the dust-shuttling system in September 2011, with a total cost of around $20 million.
And yet, no matter the numbers or costs, finding an agreeable middle ground between jobs/industry and environmental regulations often proves difficult.
Hayes declined to give an amount of mercury emissions he would consider acceptable.
Similarly, Kerby refused to give an amount of mercury emissions he’d feel comfortable with if no regulations were in place.
“I’m not gonna give you that quote,” he said.
“But we are one of the most efficient plants in the U.S.”