ENVIRONMENTAL STATEMENT BARDOLINO DEVELOPMENT

Bardolino Development Environmental Statement
Localised disturbance to the seabed from the installation and mattressing of the pipeline
A 2 km gas export pipeline (piggybacked by a 3” chemical pipeline), and a separate umbilical,
would be laid between the Bardolino well and the existing Howe manifold. The pipelines and
umbilical would be laid in two separate trenches. The trenching of the pipelines and umbilical has
the potential to impact the seabed sediment and organisms living within it.
The trenching operations would disturb the seabed along a 6 m wide corridor at the top of a deep
‘vee’-shaped trench. A narrow, 2 m wide band of seabed on either side of each trench would be
affected by the deposition of soil excavated from the trenches, and it is estimated that a total area
of 0.02 km 2 of seabed would be temporarily impacted by the trenching operations.
There are no proposed or designated conservation sites in the immediate vicinity of the Bardolino
development. Access along the pipeline route for other users of the sea would be restricted for
the period during which installation will take place, estimated to be about 6 weeks.
The potential impact of the installation and presence of the pipeline is therefore considered to be
insignificant.
Installation and physical presence of the subsea structures
The installation of a new production manifold, a production tree and a valve skid would result in
highly localised physical disturbance of the seabed sediments and associated fauna. This would
result in loss of habitat in the area directly below the subsea structures, with consequent impact
on the seabed-dwelling organisms.
The subsea structures are located in an area of low commercial value for all fish species caught
by UK fishermen in comparison to all areas fished around the UK. The main fishing gears used in
the area are demersal / bottom trawling methods which have the greatest potential to interact with
subsea structures.
The subsea structures would be enclosed within protective tubular steel frames, which are
designed to have a fishing-friendly profile. No significant operational problems for demersal
trawling are foreseen from the presence of the protected structures on the seabed.
Underwater noise that would arise from the Bardolino development
Underwater noise would be generated by the activities associated with the Bardolino
development. The main source of underwater noise would be from piling two subsea structures
to the seabed. The duration of the piling activities would be approximately 12 hours per structure,
and there would be a gap between the two operations. Marine mammals could be impacted by
noise during these operations; they may take avoidance action if they are disturbed, but evidence
indicates that they would return once activities have ceased. Densities of cetaceans in the area
are low compared to other areas of the North Sea.
Noise levels from these activities are unlikely to cause anything more than a temporary local
disturbance to marine mammals. Shell will ensure that piling will only begin during daylight hours.
A qualified and experienced marine mammal observer (MMO) would be present on the standby
vessel throughout the operations, to monitor the presence of marine mammals in the area. Piling
would only begin when it was confirmed that marine mammals were not present in a pre-defined
area close to the piling site. A “soft start” would be undertaken for each new period of piling, so
as to alert marine mammals in the area and give them the opportunity to move away.
Discharge of produced water at the Nelson platform
The Bardolino development will result in an increase in the quantity of produced water discharged
at the Nelson platform; the increase is likely to be