RICHLAND, Wash. - A Hanford environmental cleanup contractor has earned $9.9 million in incentive pay from the Department of Energy for its work at the nuclear reservation.

The Tri-City Herald reported Monday the company would have gotten more had radioactive contamination not spread during demolition of the site's Plutonium Finishing Plant.

CH2M Hill Plateau Remediation Co., owned by Jacobs Engineering Group, is responsible for much of the Hanford nuclear reservation cleanup.

CH2M received 89 percent of the possible $11 million incentive pay for fiscal year 2017.

In June, 350 workers at the highly radioactively contaminated plant were ordered to take cover indoors when a monitor detected low levels of airborne radioactive particles.

The amount of plutonium was below levels considered a risk to human health, but the fact that radioactive particles were found three miles from the plant concerned state officials.

In December another spread of contamination occurred.