Soil Guideline Values (SGVs) are a series of measurements and values used by the United Kingdom's Department for Environment, Food and Rural Affairs (DEFRA) to measure contamination of the soil. It is based on a series of toxicology reports from 1992 and is designed to show the chances and results of contamination to a particular piece of land.
SCV's include many sub-values and guidelines, most oriented around soil coverage and toxic deposits such as mercury.