Washington River Protection Solutions (WRPS) has resumed work to empty waste from Hanford Site Tank AY-102 as it faces a March 4, 2017, retrieval deadline under a settlement agreement with Washington state.

The Department of Energy’s Hanford tank farm contractor halted work on the double-shell tank leaking waste between its shells this spring to change out the retrieval systems. Work did not restart as planned as soon as September because DOE and WRPS were prohibited by a federal judge from performing work that disturbed waste and could increase the potential for releases of chemical vapors from the tanks.

U.S. District Judge Thomas Rice lifted the prohibition last month, determining that requirements for supplied air respirators should adequately protect workers until a lawsuit brought by Washington state and other plaintiffs is decided at a trial scheduled for October 2017. To further protect workers, WRPS has planned the work for night and weekend shifts when few Hanford workers are on site.

Work has been slowed by bad weather, with the site closed at times recently due to snow and icy roads. On some other nights and weekend days the temperature has been too cold for retrieval to proceed. While workers have been able to conduct some sluicing to move waste in Tank AY-102 toward a central pump, no measurable amount of waste has been removed since work resumed the second weekend of December. Hanford workers emptied most of an estimated 800,000 gallons of waste from the tank in March and April, but the sluicing system being used then could not reach the last 40,000 gallons of sludge. More and better sluicers have been installed to finish the job.