The Savannah River Site's liquid waste contractor announced the closure of two more liquid waste tanks in a press release on Thursday, stating the tanks were closed two years ahead of schedule.

Savannah River Remediation – or SRR – closed down Tanks 5 and 6, marking the completion of a four-month process. The contractor began closing the tanks in August and removed 730,000 gallons of hazardous waste from both.

“DOE is committed to protecting our workers, the public and the environment while achieving risk reduction in compliance with our commitments,” David Moody, DOE Savannah River Operations office manager, stated in the press release. “By closing four waste tanks in less than two years, we continue reducing that risk. What we are celebrating is a testimony to the fact that we deliver.”

SRR used more than 1.8 million gallons of specially formulated grout to execute the closure. The grout was delivered by 1,150 cement trucks and helps reduce the risk of the legacy waste.

Several groups, including the South Carolina Department of Health and Environmental Control, have heralded the waste tanks as the biggest threat to environmental health in the state. In September, the health department threatened to fine DOE $150 million if the waste cleanup and other milestones were not met on time.

The deadline for closures of Tanks 5 and 6 was slated for December 2015, putting SRS two years ahead of schedule. The Site now has 45 remaining tanks, with nine in waste removal or cleaning phases.

Ken Rueter, SRR's president and project manager, said the achievement is a testament to SRR being the leader in tank closure.

“Historically, SRS liquid waste employees were the first in the country to operationally close waste tanks,” said Rueter in the press release. “No other project in the nation continues to reduce the risk associated with this legacy waste like SRR employees at SRS.”

Derrek Asberry is a beat reporter with the Aiken Standard. He joined the paper in June. He is originally from Vidalia, Ga., and a graduate of Georgia Southern University.

Follow him on Twitter @ DerrekAsberry.