Oregon Public Broadcasting

The federal government has announced new regulations that for the first time cut mercury emissions from cement kilns. As Kristian Foden-Vencil reports, the dirtiest kiln in the nation is in Oregon.

Cement kilns are massive.  Jim Pew of Earth Justice says they’re essentially a rotating drum the length of a football field, in which limestone is cooked -- emitting a chemical dust.

Jim Pew: “This is the perfect storm of pollution. They use cheap fuel usually coal so there’s a lot of pollution that comes out of the coal. There’s a lot of impurities in the limestone. You can’t heat rock to 2600 degrees without liberating all the metals, mercury, arsenic, lead, chromium that happen to be in the limestone. And because it’s using so much energy, there’s a lot of carbon emissions too.”

Over the last 10 years, a series of lawsuits have forced the Environmental Protection Agency to regulate the kilns. The federal government has now set limits for how much mercury, dust and hydrochloric acid can be emitted for each ton of cement.

Ash Grove Cement, whose kiln in Durkee, Oregon, emits the most airborne mercury in the nation, says it hasn’t had time to review the regulations, but is moving forward with an emissions reduction program.