(Certified Best Practice by BMPCOE)
Department of Energy, Oak Ridge Operations - Oak Ridge, TN
An extensive environmental restoration effort is underway at the DOE Oak Ridge Facilities. The objective of this effort is to develop and apply technologies that can provide data or remediate a site in situ, thereby averting the need to excavate, creating problems and expense related to worker exposure, environmental releases, and waste disposal issues.
Vitrification (ISV) involves melting a disposal trench in place to produce a
solid, relatively impermeable mass of glass and crystalline material
encapsulating the wastes. This ISV process is achieved by placing a metal dome
with four graphite electrodes into the trench and heating the trench to 1,500
degrees C, creating a man-made magna chamber melting the trench and the waste
within the trench. The metal dome is placed over the melt to collect gases and
particulates released from the melt. The collected off-gas is cooled,
scrubbed, and filtered to remove any released materials before discharge. Once
cooled, the matter vitrifies into a glass-like substance which can not be
penetrated by ground water.
This method is a cost effective means of removing small isolated areas of contamination/waste. There is low worker exposure to the waste and considerable monitoring of events in the chamber. This method has been conducted on a pilot scale at Oak Ridge National Laboratory (ORNL) and will be conducted on a real trench at ORNL in 1996. There are several characteristics of the ISV technology that offer attractive benefits to government and private applications including: