Editing Groundwater toxic contaminant concentration (section)

== Boundary Conditions ==
Boundary inclusions encompass dissolved toxic heavy metals and related chemical species present in groundwater that are measurable by established analytical methods. This includes naturally occurring geogenic contaminants and anthropogenically introduced pollutants. Boundary exclusions include non-toxic substances, particulate-bound contaminants not dissolved in groundwater, and contaminants outside the groundwater medium such as surface water or soil-bound pollutants. The signal does not include biological contaminants or radiological substances unless chemically classified as toxic heavy metals.