Confusion in the use of Soil Guideline Values in contaminated land risk assessments has led to an overclassification of sites as contaminated in the UK. This 
has come about as result of some assessors using SGVS as a threshold value rather than a representation of minimal health risk.  As a result Defra has recently 
published proposals to alter contaminated land assessment. The most significant of these is to increase SGVs to a level consistent with the legal definition 
of unacceptable risk. Under these revised SGVs some sites previously classed as contaminated may no longer be so.