Savannah River Site liquid waste contractor Savannah River Remediation this month on Monday began a liquid tightness test on Saltstone Disposal Unit 6 (SDU 6), the site announced yesterday. The purpose of the test on SRS’ first 30-million gallon, mega-volume salt waste disposal unit is to qualify the newly constructed SDU 6 for use. The test will involve filling the facility with water to check for potential leakage, an expected 22-day process, according to an SRS press release. The full test is expected to be complete in November, when a dye/tracer and approximately 322 gallons of rhodamine WT will be “introduced” to the unit, and mixed using submersible pumps, the release says.