Opinion ID: 4565249
Heading Depth: 3
Heading Rank: 1

Heading: Operations at the Site

Text: Asarco and its predecessors owned and operated a lead smelting facility at the Site from 1888 to 2001. Asarco’s lead smelting facility was the largest operation at the Site. This operation recovered lead and other metals by smelting a variety of foreign and domestic concentrates, ores, fluxes, and other non-ferrous, metalbearing materials and byproducts. Those materials contained arsenic concentrations as high as 190,000 parts per million (“ppm”). ASARCO V. ATLANTIC RICHFIELD 5 The smelting operation produced slag as a waste product, which contained small residual quantities of metals and arsenic. It is undisputed that Asarco “released significant amounts of arsenic into the environment” from its smelting facility. Atlantic Richfield is the successor in interest to Anaconda, which leased a portion of the Site from Asarco to construct and operate a zinc fuming plant. Using a blast furnace fueled with coal, Anaconda reprocessed slag that it purchased from Asarco to recover zinc. Anaconda used and produced several arsenic-bearing materials in its fuming operation, albeit with a lower arsenic concentration than Asarco’s primary materials. Anaconda operated the zinc fuming plant from 1927 to 1972, at which point it sold the plant to Asarco. Asarco then operated the zinc fuming plant for another decade.