Colorado Department of Public Health and Environment inspectors claim Cemex ran a faulty filtration system and allowed trucks to stir up dust on its property just east of Lyons based on observations from a June 14 inspection. Most seriously, inspectors claimed the plant burned coal in its cement kiln at illegally high temperatures throughout 2004, based on CDPHE-required data that tracks heat in the kiln. If substantiated, the charges could cost Cemex up to $15,000 a day in fines, CDPHE officials say. In an Oct. 20 meeting with health inspectors, Cemex representatives claimed the high kiln temperature readings are faulty data caused by a computer glitch. “The computer was not recording correct information,” plant manager John Lohr said last week, discussing his comments at a meeting with health officials.

A series of power outages caused the computer system that records the cement kiln’s internal temperature to misinterpret the data it received from heat sensors, Cemex officials argue on a recording of the Oct. 20 meeting. A second system that monitors the kiln temperature recorded data that show the kiln was in compliance, Cemex officials said. Regulations prohibit Cemex from burning coal at a temperature higher than 517 degrees Fahrenheit. Burning coal at excessive temperatures releases too many harmful pollutants into the air, health officials say. Pam Milmoe, an air-quality official with Boulder County Public Health, said Cemex’s excuse is irrelevant.

Cemex recently won a legal challenge when Boulder County’s chief district court judge upheld a previous ruling that cleared the way for the company to burn tyres. Environmentalists and nearby residents had argued that the plant should not be allowed to fuel its cement kiln with tyres. But the latest violations are proof that Cemex should not be able to burn tyres because it cannot be trusted to burn coal properly, locals said.