The following simple approach can be used to ensure that you do not inadvertently introduce new hazards to a receiver site OR significantly increase the hazards that are already present:
In most cases this conservative approach will be sufficient to prevent the importation and reuse of materials in a way that the Regulator may consider to be “Sham Recovery”. It should also prevent the inadvertent creation of any significant problems for any future regeneration of the site.
In the unlikely event that the concentration of some substances at the receiver site are already above the hazardous waste classification thresholds but are not posing any unacceptable risks (as demonstrated by your site specific risk assessment agreed with the regulators), then raise the issue with the Environment Agency when seeking approval for the Cluster Project. In exceptional circumstances you may be allowed to import materials with levels of substances equal to or below the levels already existing at the receiver site. To do this the Environment Agency will need to be satisfied that the proposal is not unnecessarily substituting hazardous materials for non-hazardous alternatives (i.e. Sham Recovery).