The U.S. Energy Dept., the U.S. Environmental Protection Agency and the Washington State Dept. of Ecology on Oct. 6 asked a federal district court in Spokane, Wash., to approve a 2009 agreement that would give DOE many more years to clean up 53 million gallons of radioactive waste still in 149 leaking single-shell tanks at the Hanford nuclear-waste site near Richland. Energy Secretary Steven Chu said the pact “represents an important milestone in the ongoing cleanup efforts” there, but environmentalists urged the court to reject it, saying the agreement would delay cleanup. The agreement would extend some tank-waste cleanup deadlines but also would set new ones that are legally binding. DOE would have until 2040 to retrieve all tank waste and until 2052 to close 28 newer double-shell waste tanks. The pact also would set new timelines for a $13-billion waste vitrification plant now being built at the site that is years behind schedule.