Which element is NOT a potential receptor considered in site remediation?

The correct answer is the soil mineral composition because it does not function as a receptor in the context of site remediation. In environmental science, a receptor is generally defined as a living organism or entity that can be impacted by contaminants or pollution at a site. Humans, wildlife, and vegetation are all considered potential receptors because they can be directly affected by exposure to hazardous substances in their environment.

Soil mineral composition, while important for understanding the characteristics of the site and how contaminants may behave, does not itself experience effects from contamination in a manner that would categorize it as a receptor. Instead, it acts more as a medium that can influence the bioavailability of contaminants to the actual receptors, like plants and animals.