SRR tests 30 million-gallon waste unit

SUBMITTED PHOTO SRR is performing a liquid tightness test this month on Saltstone Disposal Unit 6, the first 30 million-gallon, mega-volume salt waste disposal unit constructed at SRS.

Liquid tightness testing is underway for a Savannah River Site disposal unit to ensure the unit will be able to hold 30 million gallons of mega-volume salt waste.

The site’s liquid waste contractor, Savannah River Remediation, or SRR, has completed the primary construction on Saltstone Disposal Unit 6 – a key component of the liquid waste program.

During the testing, the cylindrical concrete unit was filled with water and a fluorescent dye to check for potential leakage outside of the unit. The purpose of the dye is to demonstrate that any damp spots found on the outside of the unit came from the liquid inside.

“While this dye in the water may not be visible to the naked eye, it may be detectable using black light,” SRR reported last month. “Because this dye is environmentally friendly, there are no health, safety or environmental concerns with discharging this dyed water in the SRS ecosystem or the Savannah River.”

Following the addition of the dye, SRR confirmed that damp spots on the outside of the unit were in fact coming from the liquid inside the unit.

“It is common and expected for a concrete structure of this size to have leaks,” SRS reported in an update.

SRR began draining the unit on Nov. 11, and it was expected to be completely drained after five to 10 days. Once the unit is repaired, the liquid tightness testing will be restarted. The smaller Saltstone Disposal Units, or SDUs, on the site also showed some leakage during testing, but were successfully repaired prior to waste disposal efforts. Once repairs have been made, the liquid tightness testing will be performed.

The unit will be drained into existing drainage water basins for a controlled discharge to the environment via the normal drainage flowpath, according to SRS.

When discharged, the water will traverse over land and will empty into an on-site tributary to the Savannah River, located more than a mile away.

Derrek Asberry is the SRS beat reporter for the Aiken Standard and has been with the paper since June 2013. He is originally from Vidalia, Ga., and a graduate of Georgia Southern University. Follow him on Twitter @DerrekAsberry.