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Part  B  -  Minimum  Requirements  on  geological  survey

4  Objective
4.1  Geological  survey
Geological  survey  is  used  to  record  the  planning  area  regarding  lithological  and  tectonic
structures  as  well  as  general  bedding  conditions  and  assessment  of  the  soil  from  a  geological
viewpoint.  Geophysical  profiles  must  cover  the  planning  area  with  a  regular  grid.  Changes  can
be  made  to  this  if  certain  circumstances  provide  sufficient  justification  to  do  so  (e.  g.  following
a  channel  structure  in  the  subsurface).  Alongside  geological  units,  obstacles  that  have  been
found  i.e.  wrecks,  submarine  cables,  metal  parts  and  other  hazardous  objects  such  as  ordnance ­
  must  also  be  documented  if  they  are  not  on  the  navigational  chart.
If  differences  arise  from  the  findings  of  the  geological  survey  and  the  preliminary  geotechnical
investigation  during  the  development  and  construction  phases  which  render  relocation  of  the
structures  necessary,  the  new  sites  must  be  checked  regarding  their  suitability  on  the  basis  of
additional  geophysical  records  and  geotechnical  explorations.
4.2  Inspection
After  construction  the  area  of  the  seabed  around  the  structures  must  be  monitored  for  the
build-up  of  scours  and  the  cable  route  corridors  must  be  monitored  to  ensure  that  the  minimum ­
  cover  is  ensured  or  that  potential  uncovering  of  the  cables  does  not  take  place.  In  addition, ­
  the  state  of  safety  measures  such  as  e.  g.  scour  protection  and  gravel  dumping  should  be
monitored.
Inspection  programmes  should  be  carried  out  in  accordance  with  the  requirements  of  periodic
inspections  according  to  Standard  Design.
In  the  first  couple  of  years  after  construction  of  offshore  structures,  inspection  should  take
place  once  per  year  as  a  normal  case,  namely  early  in  the  year  (directly  after  stormy  periods).
The  findings  should  be  presented  in  a  inspection  report  as  part  of  periodic  investigations,  and
this  should  be  submitted  to  the  approval  authority  at  the  end  of  the  calendar  year.

5  Technical  guidelines
In  Tables  3  to  6  the  objectives,  scope,  time  frames,  methods  and  presentation  of  results  with
all  required  technical  details  is  shown  for  the  respective  procedure,  and  these  give  an  overview ­
  regarding  the  minimum  requirements  of  geophysical  investigations  for  geological  exploration ­
  and  inspection.