In subsurface planar vitrification, all melting operations are performed at the site of contamination. A very tall (around 6 meters deep), narrow cavern is dug into the contaminated soil, which serves as the melting container. Very large electrodes are positioned within the cavern to optimize melting times. The hazardous waste is then mixed with soil inside the cavern and the melt is initiated. After the glass product has been formed, it is either left in the ground or transferred to a disposal facility.