Cemex malfunction concerns some

Failed exhaust fan sent up plume of dust visible for miles

By Todd Neff, Camera Staff Writer

August 27, 2005

An electrical failure this week at the Cemex Inc. cement plant east of Lyons shut down a kiln fan and sent skyward a cloud of dust and exhaust visible for miles.

Richard Cargill, a Cemex watchdog who lives two miles east of the plant, said he stepped outside at 10:30 a.m. Thursday to see white dust "starting to billow out like a cloud."

Cargill said he called the Cemex control room Thursday morning and an employee told him there was an emergency at the plant. He said Eric Hodek, Cemex's environmental manager at the Lyons plant, called him back 10 minutes later and said the exhaust fan pulling air from the kiln had failed.

Exhaust from the 3,000-degree brew of cement constituents quickly pressurized and blew exhaust and particulate matter out of the system.

Hodek did not offer further details Friday, although he confirmed that the incident happened at about 10:15 a.m. Thursday. He said the problems was quickly fixed; the fan and kiln were operating normally by 10:45 a.m.

Cargill said he's concerned that burning used tires in addition to coal, as Cemex plans to do pending a court decision, would introduce more pollution when such events happen. Pam Milmoe, air and waste coordinator for the county health department, said two federal studies showed tire burning would not violate health standards.

The federal Clean Air Act requires industrial facilities to contact state health officials on the phone and in writing in case of "upsets," or unexpected events that release abnormal amounts of emissions. Boulder County Public Health also is notified, Milmoe said.

She said Cemex reported to the state and county that a malfunctioning motor drew down power to the control room, which in turn caused the fan shutdown. She said such events can blow particulate matter, nitrogen oxides, sulfur dioxides and carbon monoxide out of the kiln without necessarily passing through pollution-control equipment. She said higher-than-normal temperatures coming from the kiln is a concern to the health department primarily because toxic dioxins/furans are formed at high temperatures.

Milmoe said the exhaust temperature measured at the inlet to pollution-control equipment during the incident was 522 degrees — 5 degrees above the maximum health standard under normal operation. She said the plant produces just one ten-thousandth of state limits when operating at the maximum temperature.

"I haven't looked into other emissions, but for dioxin/furan, I don't think there's a reason for major concern at this point because this plant operates so far below standard," Milmoe said.

Kayann Short, an owner of Stonebridge Farm, a 10-acre organic farm across Colo. 66 from the plant, didn't see the cloud Thursday, but said she had seen others.

Bob Jorgenson, supervisor of the enforcement section of the state health department, said malfunctions are a part of industrial operations, and that Cemex didn't appear to file an exceptional number of upset reports.

"I don't really see that Cemex is a lot different than some of the other plants that we inspect," Jorgenson said. "You have a tremendous train of equipment that has to keep operating, processing tons and tons of material and rock. Things are going to break and equipment's going to fail."

Contact Camera Staff Writer Todd Neff at (303) 473-1327 or nefft@dailycamera.com.