Assessing the Possibility of Significant Harm Occurring

According to the statutory guidance, a significant possibility of significant harm to ecological receptors occurs if  

Further details specify that a local authority should consider that there is a significant risk of significant harm if  

In recognition of the fact that assessments of this nature can be extremely difficult and complex, the guidance then states that pre-determined guideline values, presumably in the form of chemical concentrations in soil, may be used in some circumstances, as follows  

In using any guideline values, the local authority should be satisfied that  

Finally, there is a requirement that the use of such values must be withdrawn when they are inappropriate, as follows  

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