More work on the Tacoma Smelter Plume cleanup is underway.

According to the Washington Department of Ecology, crews from five different contractors are currently digging up contaminated soil at 90 residential yards in Pierce and King counties.

The yards are contaminated with arsenic and lead spread by air emissions from the former Asarco smelter in north Tacoma. Overall, the Tacoma Smelter Plume encompasses 1,000-square-mile area in Pierce, King and Thurston counties.

The cleanup is made possible by a $94.6 million settlement that the state won in 2009. Starting in 2013, Ecology has overseen cleanup of 61 yards, 86 child-care facilities and 21 parks.