Colorado health officials say Cemex Inc. has agreed to pay a US$528,000 fine and make air-quality improvements at its Lyons cement plant.

The Colorado Department of Public Health and Environment said Friday the settlement resolves alleged violations dating to 2006.

Cemex spokeswoman Jennifer Borgen says most of the violations involved monitoring, record-keeping and reporting. She says plant equipment was over-reporting pollution levels, but they were still below standards.

The settlement is separate from a federal Environmental Protection Agency lawsuit filed last month accusing Cemex of violating federal law by not installing up-to-date pollution controls at the plant. Cemex has disputed those allegations.

Lyons is about 40 miles north of Denver.