Groundwater Restoration at a Former Smelter

Restoration is currently underway for a former lead and copper smelter in El Paso, Texas that operated from approximately 1887 until 1999. As a result of the 100+ year history of operation, groundwater across most of the site footprint is impacted primarily with arsenic, with the highest concentrations and majority of groundwater flow both focused along former (now buried) arroyos. These features represent the greatest contribution of contaminant mass flux toward off site receptors, and are the key to an integrated strategy for restoration that not only protects human health and the environment but achieves the best outcome for the community of El Paso by driving the site to an endpoint that can be sustained by a minimal level of stewardship. Rather than a prescriptive approach which relied on physical and hydraulic containment through a barrier and perpetual pumping, the goal is to shift from concentration based compliance to a focus on sufficient mitigation of contaminant flux to be protective of receptors. This presentation will explain how this is being achieved through an integrated and incremental process involving source control (segregation of leachable source material), water management (mitigating rapid recharge in the arroyos to keep clean water clean), and in-situ groundwater treatment (multiple technologies to sequester and retain arsenic).