The B.C. Ministry of Environment and Parks has defined an area for a future Wide Area Remediation Plan called the Teck Trail Environmental Management Area (EM Area). An EM Area defines a geographic area that contains specified contaminants from one specific source and where properties within the area would likely be contaminated with one or more of the specified contaminants.

The Teck Trail EM Area has elevated concentrations of soil metals (arsenic, cadmium, lead and zinc) sourced from historical aerial smelter emissions and includes Trail, Rivervale, Warfield, Montrose, south Castlegar, areas of RDKB Area A and B, areas of RDCK Area J and the edges of Rossland. The EM Area encompasses approximately 8,000 properties. 

Metal levels in soil are higher closer to the operation, and decline to near natural background concentrations toward periphery areas. As such, properties in periphery areas may not require soil management. The focus of THEP within the EM Area continues to be preventing exposure to metals and reducing health risks. The near-term focus continues to be on child-occupied properties that are expected to have higher levels of metals in the soil, such as those nearest the smelter.