The Rocky Mountain News reports that Cemex was tagged with $1.5 million in penalties in late December for dust emissions and operating temperatures from its cement plant near Lyons, Colo. Cemex also is required to increase air monitoring. The violations occurred between 2004 and 2006.

The paper says that in addition to the penalty, Cemex will be barred from burning tires for fuel for 12 months. This is one of the largest air pollution penalties issued by the state.

“The state takes very seriously instances where facility operators are not vigilant, or are cavalier, about consistently adhering to the specific terms and conditions ascribed to the safe operation of their facility,” Paul Tourangeau, head of the air pollution division, said in a statement.

A statement issued by Cemex's corporate offices to the paper said the agreement “closed a major chapter in (the Lyons facility's) history” and characterized the dispute as about “primarily data-monitoring issues.”