This environmental impact assessment for Kriegers flak ... - Vattenfall

118 CONSEQUENSES OF THE WIND FARM
In most cases, noise from the wind turbines will not
be distinguishable at closer distances as the background
noise from waves and the wind is high when
the turbines operate.
Transports by helicopter and ships that are necessary
for service and repairs of the turbines, will not
signiÞ cantly increase the disturbance level as the area
is subjected to trafÞ c already.
b) Shadows
The shadows that will arise due to the wind farm will
reach maximum 2 000 metres from the turbines (see
Chapter 5.7.2.4) and will thus not have an impact on
humans onshore. Due to the temporary character of the
shadows, impact on humans in passing boats will be
small.
c) Accidents/oil spill
There are reports of blades/part of blades having come
loose, of Þ re and of towers collapsing but these are
very rare. Experience from operating turbines show
that it is mainly ß aws in steering and control that may
cause accidents.
The risk of ice covering should not be underestimated.
When a turbine is started after standstill, the
ice cover is normally shaken off and the ice falls down
along the tower. As an exception, sheets of ice can be
thrown from the blades.
The risk of turbines collapsing, that parts of the turbine
comes lose or that ice is thrown off is very small.
As the farm is 30 km away from the nearest house,
there is no risk for humans that are ashore. There is,
however, a risk for humans that are inside the farm
area, but as humans normally don’t frequent the area
or the vicinity thereof, the third party risk is minimal.
Those affected, may be service personnel and Þ shermen.
Oils and chemicals in the turbines are sealed off and
secondary containers will prevent leakage into the sea
in case of an accident.
Boat trafÞ c to and from the area will be intensive
during the construction and dismantling phases. During
this time, there is a risk of oil and material spill,
especially when laying the foundations. Small spills of
this kind will not have an impact on human health.
If a ship collision would occur, this could lead to big
oil or chemical spills that, in turn, could have a nega-
tive impact on human health.
The risk of accidents that cause oil spills, has been
calculated by SSPA to 0,0006 per year, or about 1
700 years between collisions (to be compared to the
number that has been calculated for the wind farm in
the German economic zone, namely 580 years).
The average oil spill has been estimated to 3 400 tons.
With security increasing measures, such as tugboats
on standby, the risk decreases to 0,00015 collisions per
year or about 6700 years between collisions (see Attachment
12.2).
SSPA has also calculated the risk of humans being
injured due to ships colliding with the wind farm. In
this case, the risk of accidents has been estimated to
0,000002 per year, or, provided no security increasing
measures are taken, one every 500 000 years. A
comparison with the European ferry trafÞ c shows that
the collision risk between ferries and wind turbines
is much smaller. With security increasing measures
such as AIS and trafÞ c control, the risk is reduced to
0,0000005 personal accident cases per year, or one
every 2000000 years.
Summary of impact on humans.
The wind farm is situated far from shore resulting in
no shadows reaching the shore. Also, no noise from the
turbines will be hearable onshore.
The risk of humans being injured due to falling ice
or from parts of a turbine are minimal.
If an accident occurs, for example a ship colliding
with a turbine, oil from the turbine and the ship could
leak out and cause large negative effects. The risk
thereof is, however, very small. The risk of personal injury
at such an accident is also considered as minimal.
12.1.2 Mitigating measures
A security zone will be created around the wind farm
and the turbines will be marked so as to be seen from
passing ships.
To avoid leakage, the oils and chemicals in the
turbines are hermetically sealed and a secondary container
will prevent any leakage from reaching the sea.
In case of oil still leaking out, there will be specially
prepared routines to handle smaller leakages from platforms
and boats as well as an action plan for contact
with the Coast Guard in case of an oil or chemical spill
into the sea.