Member States shall amend the list of threshold values applied in their territories whenever new information on pollutants, groups of pollutants or indicators of pollution, also taking into account the precautionary principle, indicates that a threshold value needs to be set for an additional substance, that an existing threshold value needs to be modified or that a threshold value previously removed from the list needs to be re-inserted. If relevant threshold values are established or amended at Union level, Member States shall adapt the list of threshold values applied in their territories to those values.
▼B
Threshold values can be removed from the list when the body of groundwater concerned is no longer at risk from the corresponding pollutants, groups of pollutants, or indicators of pollution.
Any such changes to the list of threshold values shall be reported in the context of the periodic review of the river basin management plans.