In another key point of the agreement, Parliament successfully demanded that Member States be required to take "all measures necessary to prevent inputs into groundwater of any hazardous substances" and not merely "all measures necessary to aim to prevent" this type of pollution, as the Council wanted.
Direktīva neieviesīs vienādas prasības par to, kāds piesārņojums uzskatāms par pieļaujamu, bet saskaņos metodes gruntsūdeņu kvalitātes vērtēšanai.