Evaluation of Hanford Single-Shell Waste Tanks Suspected of Water Intrusion-14196.

摘要

Intrusions evaluations for twelve single-shell tanks were completed in 2013. The evaluations consisted of remote visual inspections, data analysis, and calculations of estimated intrusion rates. The observation of an intrusion or the preponderance of evidence confirmed that six of the twelve tanks evaluated had intrusions. These tanks were tanks 241-A-103, BX-101, BX-103, BX-110, BY-102, and SX-106. Beginning in 1978, pumpable supernatant and interstitial liquids were removed from single-shell tanks (SSTs) at Hanford. This process was known as interim stabilization, and it was intended to limit the impact of waste leaks by leaving behind a primarily solid waste phase in the tanks. In addition to pumping, the process drain lines connected to the SSTs were capped, and the process pits were foamed in order to isolate the tanks and minimize rainwater or snowmelt intrusion. As the SSTs await retrieval into double-shell tanks, they are monitored by instruments that measure the interstitial liquid level (ILL) and/or the waste surface level (SL).