SACRAMENTO, CA - Caterpillar, Inc., will pay a fine of $510,000 to the California Air Resources Board (ARB) for shipping more than 590,000 on-road and off-road engines that did not have legally required emissions controls installed, according to a release from the ARB.

The investigation of these violations was conducted with the U.S. Environmental Protection Agency and the U.S. Department of Justice based on similar conduct outside of California. The settlement calls for the Illinois-based company to pay a total of $2.55 million in penalties nationwide for violations of the Clean Air Act.

California’s $510,000 portion is based on its share of the engines sold and will be used to support air quality research. Caterpillar also agreed to recall and correct noncompliant engines and to reduce excess smog-forming and diesel emissions, the release stated.

Caterpillar recalled the affected engines from August 2002 to April 2005. In 2010, in accordance with the federal Consent Decree, the company reopened and continued the recalls until Dec. 31, 2011.

The federal government’s claims were resolved in 2011. The state’s recent agreement concludes California’s portion of the investigation.

In addition to shipping engines without proper emission controls, the release stated that Caterpillar also failed to comply with reporting and engine-labeling requirements.

The ARB oversees all air pollution control efforts in California.