LYONS, Colo. -- State air pollution control experts have issued a notice of violation to the CEMEX cement plant in Lyons.

Allegations include, “various violations of state air quality regulations and operating permit conditions,” according to a release issued by the Colorado Department of Public Health an Environment.

The CEMEX USA plant, located northwest of Boulder, has been the source of enforcement actions taken by state and federal authorities in recent years.

“We are concerned that CEMEX continues to operate this facility without direct and consistent focus on compliance with air quality regulations and the facility’s permit,” said Paul Tourangeau, director of the department’s Air Pollution Control Division. “We expect this plant to be operated in compliance with the law, and will continue to take the actions necessary to produce that result.”

Tourangeau said the current notice of violation is the result of several on-site inspections of the plant by the Air Pollution Control Division and inspectors from the Boulder County Health Department in 2007 and 2008.

“We are disappointed that the State decided to issue a (notice of violation),” said CEMEX spokeswoman Jennifer Borgen in a statement to 7NEWS.

"It is important to note that at no time has the public’s health, safety or the environment been impacted,” Borgen said in the statement.

Among the allegations reflected in the notice are opacity violations. Tourangeau explained opacity refers to emissions that can block light.

Other concerns include failure to conduct necessary stack tests in a timely fashion, failure to operate monitoring equipment within requirements, failure to file appropriate and timely air pollutant emission notices, and record-keeping errors, according to Tourangeau.

“We had already self-reported some of these findings and had immediately implemented corrective actions,” Borgen said of CEMEX in her statement to 7NEWS .

“For instance, we did an audit and we found our CEMS (continuous emissions monitoring system) equipment was over reporting data. The equipment had not taken into account moisture content and was reporting our emissions levels higher than what the plant actually produced. This is good news, as our emissions levels were actually lower than originally reported. However, because the equipment reported the data higher than reality, this was the basis for several alleged violations. We immediately remedied the situation by installing a new Data Acquisition System that is more sophisticated and transparent,” the statement read.

Borgen said CEMEX looks forward to meeting with the Colorado Air Pollution Control Division.

As part of the notice of violation process, the company will have an opportunity to respond to the allegations, submit data and discuss whether assessment of civil and noncompliance penalties is appropriate.

The notice is the fifth enforcement action taken by the state since 2000, according to information provided by the Colorado Department of Public Health and Environment. The previous four actions resulted in settlements, including one penalty in 2006 that totaled $1.5 million, the second-largest penalty ever assessed by the Colorado Air Pollution Control Division.

A notice of violation issued by the U.S. Environmental Protection Agency last year has yet to be resolved.

"I would just call them a pay and pollute company, they've got such a long history of doing this,” said Kayann Short, who lives within a mile of the plant.

"I think our community needs to join together and say, 'no more of this,'” Short told 7NEWS.

Borgen said CEMEX hopes to resolve the matter amicably.

CEMEX is one of the world’s leading building materials suppliers, providing cement and concrete products for construction projects. Founded in Mexico in 1906, CEMEX operates numerous cement plants, distribution terminals and quarries in the United States and abroad.