Environment Report - Santos

5. Project Description
Table 5.2
Preliminary assessment of shore crossing options
Criteria Option 1
Flaxman’s Hill
Option 2
Lover’s Nook
Option 3
Newfield Bay
Option 4
Two Mile Bay
#1 Horizontal
directional drill
Unknown geotechnical
conditions.
Unknown geotechnical
conditions.
Unknown geotechnical
conditions.
Required drill length (to 15-m
water depth) from outside
Port Campbell National Park
exceeds the current technical
limit for HDD. Therefore, this
option carries significant
technical risk.
Co-located with Minerva and
Otway Gas Project shore
crossings. Known
geotechnical conditions
(Minerva HDD geological
profile has been made
available to Santos (Santos
is a joint venture partner in
the Minerva Project). Key
stakeholders indicated
support for concept of colocation
of shore crossing
site. Required drill length
within technical limits.
#2 Offshore
Environment
Bathymetry indicates
significant reef outcrops
and rocky seafloor
conditions between gas
field and shore. Confirmed
by commercial fishers
during consultation and
offshore bathymetry
survey.
Bathymetry indicates
significant reef outcrops and
rocky seafloor conditions
between gas field and shore.
Confirmed by commercial
fishers during consultation
and offshore bathymetry
survey.
Bathymetry indicates
significant reef outcrops and
rocky seafloor conditions
between gas field and shore.
Confirmed by commercial
fishers during consultation
and offshore bathymetry
survey.
Bathymetry east of Casino
gas field and near Minerva
indicates significant areas of
sandy seafloor. Confirmed by
commercial fishers during
consultation and offshore
bathymetry survey.
#3
Commercial
Fisheries
Offshore pipeline would
traverse good lobster
fishing grounds.
Creates new pipeline
corridor.
Offshore pipeline would
traverse good lobster fishing
grounds.
Creates new pipeline
corridor.
Offshore pipeline would
traverse good lobster fishing
grounds.
Creates new pipeline
corridor.
Offshore pipeline can avoid
main lobster grounds.
Co-location with Minerva and
Otway Gas Project pipeline
and therefore limits snagging
hazards to one corridor.
Commercial fishers indicated
preference for this option
over others.
#4 Onshore
Environment
Requires crossing of
Curdies River and
Campbells Creek (both
using existing easements).
Greenfield shore crossing.
Potential for approximately
90% of onshore pipeline
route to follow existing
easements.
Requires crossing of Curdie
River and Campbells Creek
(both using existing
easement). Greenfield shore
crossing. Potential
approximately 90% of
onshore pipeline route to
follow existing easements.
Requires crossing of
Campbells Creek (using
existing easement).
Greenfield shore crossing.
Potential for approximately
80% of onshore pipeline
route to follow existing
easements.
Requires crossing of
Campbells Creek (using
existing easement). Shore
crossing consolidated with
Minerva and Woodside
Otway Gas projects.
Potential to follow existing
easement for 90% of
onshore pipeline route.
or adjacent to existing easements, where
practicable, two options are available
from the HDD site to Smokey Point Road
and three sub-options are then available
from here to the TXU WUGS facility.
Note that the naming protocol for the
various onshore pipeline route options
uses ‘Option 4’ followed by either the
word ‘Minerva’ or ‘Otway’ (depending on
which alignment it follows) and the suboptions
are identified as ‘4A, B or C’.
Between the preferred HDD shore crossing
site at Two Mile Bay (Option 4) and
Smokey Point Road, there are two options
(Figure 5.3):
• Option 4 (Minerva) – follows the existing
Minerva pipeline easement to
the Minerva gas plant and then the
SEAgas pipeline to Smokey Point
Road.
• Option 4 (Otway) – follows the proposed
Woodside Otway Gas Project
alignment to Smokey Point Road.
Between the Smokey Point Road and
the existing TXU WUGS facility, there
are three sub-options (see Figure 5.3):
• 4A – Crosses north over Smokey
Point Road and Cheynes Road South
and follows the existing GasNet Iona
to Portland pipeline into the TXU
WUGS facility.
• 4B – Follows the SEAgas pipeline
from Smokey Point Road into the TXU
WUGS facility.
• 4C – Follows the proposed Woodside
Otway gas pipeline from Smokey
Point Road into the TXU WUGS facility.
Selection of the Preferred Onshore
Pipeline Alignment
The selection and assessment process
for the route alignment was based on:
• Environmental impact assessment –
studies of the various alignments
have been conducted by specialist
consultants, based on desktop and
field investigations. The field studies
were undertaken at the end of summer
2004 and included investigations
of:
– Ecology (flora, fauna and stream
ecology).
Casino Gas Field Development 23