Abstract: A process is provided for converting lead-contaminated soil to commercially-useful ceramic shapes, in which the lead is covalently-bonded and from which it does not leach. The soil is mixed with conventional brick or tile fabricating ingredients to form a premix which is formed into a suitable shape and fired at a temperature in the range of 150.degree. F. to 250.degree. F.

Abstract: A process is provided for converting asbestoform material into an environmentally safe material by heating the asbestoform material with an alkaline flux so as to change the crystalline structure of the asbestoform material to a form that is environmentally safe.

Abstract: Lead or other heavy metals are rendered immobile for sanitary disposal by vitrifying the silica-based soil or other medium in which the lead or heavy metal is contained. The silica sand or other soil contaminated with lead is heated to the melting point of the silica. A melt accelerator or fluxing agent is added to lower the melting point of the silica. A reducing agent is added to cause a separation of the metallic phases from the glass. The glass formed retains a portion of the lead, with excess metals, e.g., gold, silver, and platinum, separating. These metals may be recovered at any time after this point in the process.In the case of a silica-poor medium, such as a soil that does not contain sufficient quartz to perform the process successfully, additional quartz sand or scrap glass is added to the process in quantity sufficient to ensure the formation of the glass slag.