prior to transporting it to Celsa. In addition, the off gas during the melting of the scrap is cleaned for dust and dioxins. Mercury (Hg) occurs naturally, in almost all oil and gas reservoirs and come from the mineral cinnabar (HgS). The concentration of Hg can vary from field to field, and over time. Hg is deposited in equipment and pipes that have been in contact with gas, rarely in pipes that have in contact with oil.