An Indianapolis agricultural and nutritional chemical plant has agreed to pay a $425,000 penalty and upgrade pollution controls to resolve alleged clean air violations.

Vertellus Agriculture and Nutrition Specialties LLC settled with both the U.S. Environmental Protection Agency and U.S. Department of Justice over violations at the plant, 1500 S. Tibbs Ave., EPA said today in a news release.

EPA alleged that Vertellus failed to comply with leak detection and repair requirements of the national emission standards for hazardous air pollutants.

But Vertellus has already taken steps to come back into compliance by installing a new incinerator to control hydrogen cyanide and benzene emissions and to implement a comprehensive set of leak detection and repair practices that go beyond regulatory requirements, EPA said.

The leak detection and repair practices include an innovative program to replace valves with new low-leak valve technology and to monitor and repair equipment that is leaking at a lower rate than is required by regulations to further reduce fugitive hazardous air pollutant emissions.

For its environmental project, Vertellus has agreed to complete a two-year process to upgrade pumps with technology that will eliminate fugitive emissions of hazardous air pollutants.

Benzene is known to cause cancer in humans, and hydrogen cyanide may cause nausea, headaches and thyroid damage.