Over the past few years Alberta Environmental Protection's Chemicals Assessment and Management Division has been collecting and interpreting both ambient and industrial point source data on contaminant metal concentrations in Alberta soils. Between 700 and 800 observations have been made on 12 metal concentrations in surface soils under ambient conditions. Samples for these analyses were drawn primarily from agricultural soils prior to regulated application of municipal sewage sludge (about 200 samples) and from a program designed to sample soils from throughout Alberta in five land use categories (about 600 samples) as follows: transportation corridors, new urban and old urban parklands, rural parklands and commercial sites. Several hundred observations on industrial site soil quality are also available from investigations conducted under regulatory approvals, primarily for chemical plants, fertilizer plants, gas plants, rail yards, wood preservers and the metal industry.
Analyses to date have established the normal geochemical range and approximate distribution of the common contaminant metals in upland Alberta soils as well as an overview of the magnitude, frequency and nature of contamination under some land use applications.
Two major conclusions from the work to date are: (1) prediction or determination of geochemical background at a particular site is normally straightforward and non-contentious; and (2) with few exceptions, Alberta industries are doing a good job of protecting on-site soils from severe contamination by toxic metals.