Article 4

     1.  To  comply  with the obligation referred to in Article 3 (a),
Member States:
     - shall prohibit all direct discharge of substances in list I,
     - shall  subject  to  prior investigation any disposal or tipping
for  the  purpose  of disposal of these substances which might lead to
indirect  discharge. In the light of that investigation, Member States
shall  prohibit  such  activity  or shall grant authorization provided
that all the technical precautions necessary to prevent such discharge
are observed,
     - shall  take  all  appropriate  measures  they deem necessary to
prevent  any  indirect  discharge  of  substances  in  list  I  due to
activities  on  or  in  the  ground  other than those mentioned in the
second  indent.  They  shall  notify  such measures to the Commission,
which,  in  the light of this information, may submit proposals to the
Council for revision of this Directive.
     2.   However,   should   prior   investigation  reveal  that  the
groundwater  into  which  the  discharge  of  substances  in list I is
envisaged   is  permanently  unsuitable  for  other  uses,  especially
domestic   or  agricultural,  the  Member  States  may  authorize  the
discharge  of  these  substances provided that their presence does not
impede exploitation of ground resources.
     These  authorizations  may  be  granted  only  if  all  technical
precautions  have  been  taken  to ensure that these substances cannot
reach other aquatic systems or harm other ecosystems.
     3.  Member  States  may,  after  prior  investigation,  authorize
discharges due to re-injection into the same aquifer of water used for
geothermal  purposes,  water pumped out of mines and quarries or water
pumped out for civil engineering works.