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ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
i
NON-TECHNICAL SUMMARY
INTRODUCTION
This is the Non Technical Summary of an Environmental Impact Assessment
(EIA) for an offshore multiple well exploration drilling programme (the
Project). The programme will be conducted within the Sigguk exclusive licence
2008/10 (Sigguk Licence) off west Greenland between June and October 2010,
with a two month contingency window over November and December in case
relief well drilling is required. The EIA has been produced by Environmental
Resources Management (ERM) on behalf of Capricorn Greenland Exploration-
1 Ltd (Capricorn), a subsidiary of Cairn Energy PLC (Cairn).
This EIA includes details related to the entire drilling programme as it is
important that the impacts associated with drilling individual wells are not
assessed in isolation, but considered as part of the wider drilling project.
Detailed environmental survey data is only included for the first two wells of
this programme (Alpha and T8) and this EIA is therefore only intended to
accompany the drilling application for these two wells. Further revisions of
the EIA which include the results of environmental surveys for subsequent
wells will therefore be produced for any drilling application beyond the first
two wells.
The EIA has been undertaken in accordance with applicable Greenland
legislation and standards, international guidance and the corporate policies
and expectations of Cairn.
EIA Standards and Permitting
The regulatory framework for offshore oil and gas activities in Greenland is
currently being revised. The Bureau of Minerals and Petroleum (BMP) is the
main implementing agency for laws relating to hydrocarbon exploration, and
has been consulted throughout this EIA process.
Scope
As well as the EIA, a separate Social Impact Assessments (SIA) has been
produced for the Project by ERM on behalf of Capricorn. Social, economic and
health factors are therefore excluded from the EIA and covered by the SIA.
In preparing this EIA, a range of existing information sources and new studies
have been used. A comprehensive literature review has been conducted using
reports prepared by environmental organisations from Greenland and
Denmark, as well as information sourced during internet research and the
results of computer modelling and simulations. Field surveys have been
conducted to investigate the physical, chemical and biological environment
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
ii
and studies have been undertaken on weather patterns, ice movements and
currents.
The geographical scope of the EIA includes the Sigguk Licence (also referred to
as the Sigguk Block or the Licence Area) together with the wider marine and
coastal environment where relevant to the potential impacts of the Project.
The focus of the EIA is on the locations within the Sigguk Licence where the
exploration wells are to be drilled (see Figure 1 below).
Figure 1 Sigguk Exclusive Licence 2008/10 Off West Greenland
Proponent and EIA Practitioner
Capricorn Greenland Exploration-1 is a subsidiary of Cairn Energy PLC based
in Edinburgh, UK. Cairn is an independent, public oil and gas exploration
and production company quoted on the London Stock Exchange.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
iii
ERM is a leading global provider of environmental, health and safety, risk,
and social consulting services, with 137 offices in 39 countries employing
approximately 3,300 staff. ERM is a corporate member of the Institute of
Environmental Management and Assessment (IEMA) and has worldwide
expertise in environmental and social impact assessment for offshore oil and
gas projects, including operations in Arctic waters.
ASSESSMENT METHODOLOGY
Overview of the Impact Assessment Process
This EIA has been undertaken following a systematic process that predicts
and evaluates the probable impacts of the Project on aspects of the physical
and biological environments; it identifies measures to mitigate adverse
impacts, and to provide benefits, as far as is reasonably practicable.
The overall approach is shown in Figure 2. Screening and Scoping for the EIA
(and SIA) has been underway throughout Project planning and has involved
consultation with the Greenland Government and key stakeholders, review of
legislation and international standards and examination of previous
environmental studies. Engagement with the authorities and key Non-
Governmental Organisations (NGOs) has continued throughout this process,
as has interaction with the Project Team.
Figure 2 Overview of IA Approach
Baseline Data Collection
To provide a baseline against which potential impacts can be assessed, the EIA
provides a description of the conditions that will prevail in the absence of the
Project. The baseline includes information on all receptors and resources
Screening
Scoping
Sta
keh
old
er e
ng
ag
em
en
t
Inte
racti
on
wit
h p
roje
ct
pla
nn
ing
an
d d
esig
n
Baseli
ne s
tud
ies (
exis
tin
g d
ata
co
lle
cti
on
an
d n
ew
su
rveys)
Predict magnitude of impacts
Evaluate their significance
Investigate options for mitigation
Reassess residual impact (as required)
Assessment
Management Plans/
Mitigation Register
Reporting and Disclosure
Screening
Scoping
Sta
keh
old
er e
ng
ag
em
en
t
Inte
racti
on
wit
h p
roje
ct
pla
nn
ing
an
d d
esig
n
Baseli
ne s
tud
ies (
exis
tin
g d
ata
co
lle
cti
on
an
d n
ew
su
rveys)
Predict magnitude of impacts
Evaluate their significance
Investigate options for mitigation
Reassess residual impact (as required)
Assessment
Management Plans/
Mitigation Register
Reporting and Disclosure
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
iv
identified as having the potential to be significantly affected by the proposed
Project. For this IA, baseline data collection proceeded in several stages:
• Collection of available data from existing sources including:
o government agencies;
o research and academic organisations;
o published sources;
o external stakeholders and the public; and
o previous offshore exploration Preliminary EIAs held by the client.
• Environmental and geophysical surveys of the well site locations to inform
the physical and biological components of the baseline, including physical,
chemical and biological analysis of samples taken.
• In-country information gathering and stakeholder interviews to inform oil
spill sensitivity mapping and socio-economic baseline for the SIA.
Assessment of Impacts
The assessment describes what will happen by predicting and quantifying as
far as possible the magnitude of impacts. The term ‘magnitude’ is used as
shorthand to encompass all the dimensions of the predicted impact including:
• the nature of the change (what is affected and how);
• its size, scale or intensity;
• its geographical extent and distribution;
• its duration, frequency, reversibility, etc; and
• where relevant, the probability of the impact occurring.
Magnitude also includes any uncertainty about the occurrence or scale of the
impact. An overall grading is provided to determine whether an impact is of
negligible, small, medium or large magnitude.
The next step in the assessment process is to explain what the magnitude of an
impact means in terms of its importance to people and the environment. This
is referred to as Evaluation of Significance. Criteria for assessing the
significance of impacts are clearly defined and take into account whether the
Project will:
• Cause legal or accepted environmental standards to be exceeded, or make
a substantial contribution to the likelihood of a standard being exceeded.
• Adversely affect protected areas or valuable resources, conservation areas,
rare or protected species, protected landscapes, historic features.
• Conflict with established government policy, for example to reduce CO2
emissions or recycle waste.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
v
Magnitude and sensitivity are looked at in combination to evaluate whether
an impact is significant and if so its degree of significance (see Figure 3).
Figure 3 Evaluation of Significance
Mitigation and Residual Impacts
Where the assessment results in significant impacts, methods for practical and
affordable mitigation are identified. These measures have been agreed with
the Project proponent and integrated into the Project design. Following
agreement on feasible mitigation, impacts are re-assessed taking into account
the mitigation measures now integrated into the Project. Where an impact
could not be completely avoided the residual impact has been reassessed and
the possibility for further mitigation considered.
ENVIRONMENTAL SETTING
Physical Environment
Climate
The mean monthly air temperatures for sampling sites to the north and south
of the block varied from a minimum of -21.96 °C to the north of Sigguk and a
maximum of 13.15 °C to the south of Sigguk. Average precipitation at the
nearest towns of Aasiaat and Sisimiut varied from 16 mm at Aasiaat in
January and February to 52 mm at Sisimiut in August. Wind speeds at the
Alpha wellsite location varied between an average of 2.9 m/s in July and
6.17 m/s in October (see Figure 4).
Magnitude of Impact
Va
lue
/Se
nsiti
vity
of
Reso
urc
e/R
ece
pto
r
Small Medium Large
Hig
hM
ediu
m
Low
Not Significant
Minor
Moderate
Major
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
vi
Figure 4 Comparative Wind Speed Frequency by Direction (July to October)
Source: C-Core, 2009
Bathymetry
The transition to continental slope off central West Greenland occurs at
approximately 400 m deep. Near the Sigguk block the continental shelf is
incised by a broad deep, low-relief channel, informally named the
Uummannaq Channel. The Sigguk block varies in depth from around 300 m
in the east of the block to 1,840 m in the northwest of the block. The first two
wells to be drilled will be located in water depths of 300-450 m. Other
potential drilling sites within the licence area lie in water depths of 370-620 m.
Seabed
The seafloor and shallow geology throughout the Sigguk block is
characterised by a thin layer of relatively fine grained, well sorted, poorly
consolidated sediments that blanket the area and accumulate in seabed
depressions. Surveys of the area have found that areas of the seabed have
been heavily scoured by icebergs. The sediments at both initial drilling sites
are predominantly sandy silt with clay and a small fraction of gravel and
coarser sediment, and with occasional larger, ice-rafted rocks of variable size.
Sediment sampling has been carried out at both initial drilling sites and shows
low organic content of sediments, ranging from < 0.05% to approximately
0.5%.
Oceanography
Surface circulation shows the West Greenland Surface Water flowing north
over the shelf along the west coast of Greenland and Arctic Surface Water
from the Canadian Arctic Archipelago flowing south along the eastern coast of
Baffin Island. Below these surface waters a branch of the Irminger Current
flows north forming West Greenland Intermediate Water over the bulk of the
West Greenland Shelf Slope while Arctic Water and Transition Water flow
south over the western side of the basin. The study site is located near the
transition between north flowing shelf waters to the east and south flowing
waters over the bulk of the basin to the west (see Figure 5).
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
vii
Figure 5 Regional Currents off West Greenland
Source: Brian Petrie, Bedford Institute of Oceanography
Generally, currents in the study area are weak. The mean surface currents at
the two initial well sites are in the range of 2-3 cm/s up to a depth of
approximately 50 m. Wave heights in eastern Baffin Bay are small. When
larger waves do occur, they are usually of short duration. The maximum
average significant wave height within the Sigguk block occurs from
November through January which coincides with peak monthly wind speeds.
Sea surface temperatures off the west coast of Greenland are lowest in January
and February and highest in August at approximately 6 to 8°C, although
variation throughout the year is low. Sea surface salinity in the study area
also shows little variation.
Ice Conditions
In the Sigguk block, the period between mid-June and mid-November is
normally ice free but occasionally sea ice may drift from the central sections of
southern Baffin Bay into the area during the summer. When sea ice does
occur it tends to be very large floes of thin first year ice. However, the cover
of ice is changeable and large areas of open water are common.
Ice thickness in Davis Strait is highly variable. Ice formed in newly opened
leads often develops a thickness of greater than 0.5 m during winter months.
Older ice that begins forming in autumn often grows to thicknesses of 1.2 m.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
viii
Figure 6 Total Concentration of Ice at the Project Area June to October (2007 data)
Source: C-Core, 2009
The drift pattern of sea ice off west Greenland is not well understood, with
local drift to some extent controlled by the major surface systems together
with the strength and direction of the surface winds, especially in southern
waters. Nearly all ice drift in the western portion of Davis Strait is in a
southerly direction, with typical velocities observed in southern Baffin Bay
during winter and spring of 10 cm/s increasing to 20-30 cm/s in Davis Strait.
Icebergs are formed when ice at the outlets of glaciers on the west coast of
Greenland calve from the glacier. Icebergs are formed on the west coast
throughout the year and are carried by sea currents, but also affected by the
wind. Ummannaq Fjord and Disko Bay are important sources of icebergs to
the Disko West region. These areas can produce 10,000-15,000 icebergs per
year. Icebergs tracked for the Project had a mean drift speed of 0.21 m/s and
varied from almost stationary to a maximum of 1.59 m/s (3.1 knots) during
storm conditions. These icebergs drifted in almost all directions but
predominantly east with variability in drift direction caused by the prevailing
current pattern.
Sediments
Environmental surveys at the proposed drilling sites studied the physical,
chemical and biological characteristics of the seabed. Sediment samples from
the well locations and regional samples from other points within the licence
area showed organic content of the sediment to be low, with hydrocarbon
levels consistent with naturally occurring hydrocarbon levels and no
indication of hydrocarbon contamination.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
ix
Biological Environment
Primary Production
Primary production (organic matter produced by photosynthesis eg
phytoplankton or algae) off western Greenland is high, although the
important spring bloom usually starts in late April and develops throughout
May, therefore coming before the planned operations. Most primary
production occurs close to the coast and in fjords, with high levels of primary
production also occurring at marginal ice zones.
Zooplankton
Various types of zooplankton (eg shrimp, crustaceans) are present in the
waters off west Greenland and form a key food source for many other species
in this area such as fish, whales and seabirds. More than 85% of the
zooplankton present are crustaceans. The most common are Calanus
copepods which have been found in high numbers over the fishing banks and
deeper waters of Disko Bay.
Invertebrates
Benthic communities are an important ecosystem component on the West
Greenland continental shelf in Baffin Bay, although relative importance
decreases with increasing depth and distance from shore. The benthic
communities found at the two initial wellsite locations were very similar as
they have similar seabed substrates (ice modified silty sediments). No
protected or particularly sensitive habitats were found (eg coral reefs).
Species abundance was comparable or higher than other studies in western
Baffin Bay or southern Davis Strait but was lower for comparable depth
ranges and had similar abundances to those studies conducted in deeper
waters. The diversity of benthic animals was also lower than the southern
Davis Strait.
Fish
The waters around Greenland contain approximately 250 species of fish. Of
these, 18 species of particular importance or common off West Greenland have
been described in the EIA baseline. Thorny skate and Atlantic cod have been
assessed to be Vulnerable on the IUCN Red List, the Greenland shark has been
assessed to be Near Threatened and all other species are of Least Concern.
Most fish will spawn inshore, away from the exploration block, or at other
times of the year when drilling will not take place. The only species that may
spawn in the shallow areas of the block in June is herring.
Seabirds
Within Greenland there are 58 established breeding species of seabird, with a
further 17 species which are regular summer visitors. Due to the harsh
climate very few species overwinter in Greenland, although a number of
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
x
seabirds winter off the coast around the edge of the fast coastal ice. Seabirds
also aggregate in colonies along the coastline and up to 84% of all colonies in
Greenland are on the west coast. There are 14 species of seabird known to
breed in colonies that are found in the vicinity of the Sigguk block.
Some species of seabird moult their feathers whilst at sea and can form large
rafts of birds. These birds include common eider, king eider, Brünnich’s
guillemot and little auk. During this time they are unable to fly but are still
able to swim at some speed.
Marine Mammals
There are 19 species of marine mammal that regularly occur in the waters and
along the coast of western Greenland in the vicinity of the licence area: 13
species of whale, 5 species of seal, walrus and polar bear. Data on the
numbers and movements of marine mammals off west Greenland remain
sparse, although tracking and distribution studies are ongoing and likely
presence of certain key species can be shown, such as the Beluga wintering
grounds in Figure 7.
Figure 7 Beluga Wintering Ground
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
xi
Protected Areas and Threatened Species
Fin and blue whale are listed as Endangered on the IUCN Red List. Beluga
and narwhal are listed as Critically Endangered and bowhead whale is listed
as Near Threatened on Greenland’s Red List. All five seal species are listed as
Least Concern or Vulnerable on the IUCN Red List. The harbour seal is listed
as Critically Endangered on Greenland’s Red List. Walrus is listed as
Endangered on the IUCN Red List and polar bears as Vulnerable on both the
IUCN and Greenland Red List.
Atlantic cod and Thorny skate appear as ‘Vulnerable’ on the IUCN red list,
with Greenland shark listed as ‘Near Threatened’. A number of other species
are placed in the category of ’Least Concern’, including Arctic skate, three-
spined stickleback, Atlantic salmon, Arctic char and common grenadier.
The ivory gull is listed as Near Threatened on the IUCN list, with other
species listed as being of Least Concern. This differs from Greenland’s red list,
which lists the common eider, thick-billed murre and ivory gull as Vulnerable;
the Arctic tern, Atlantic puffin and Sabine’s gull as Near Threatened; and the
black-legged kittiwake is listed as Endangered.
Greenland has 11 Ramsar Sites (Wetlands of International Importance), of
which six are found along the west coast. Greenland’s Ilulissat Icefjord has
been designated a UNESCO World Heritage Site and several areas have also
been designated nature reserves or bird protection areas. The legally
protected areas in western Greenland are shown in Figure 8 below.
Figure 8 Protected Areas in Western Greenland
Important Bird Areas in western Greenland as identified by BirdLife
International are shown in Figure 9 below.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
xii
Figure 9 Important Bird Areas
THE PROJECT
Capricorn has a working interest in a total of eight exploration licences off the
south and west coasts of Greenland, although the current drilling programme
and the remit of this EIA is concerned solely with the planned exploration
programme in Block 1, Sigguk. The drilling programme is planned to take
place over four months, with a two month contingency for relief well drilling
in case of a major unplanned event (see Table 1 below).
Table 1 Outline Drilling Schedule
2010 May June July August Sept Oct Nov Dec
Mobilisation
Drilling (4 wells)
Relief Well
The programme will involve the drilling of four wells, with the possibility of
drilling up to a further two wells in the same block within the existing project
schedule should initial drilling go faster than expected and if it proves
operationally worthwhile.
The drilling programme itself will employ a range of cutting-edge technology
and operating standards to meet the challenges of drilling in the offshore
Arctic environment. Two mobile offshore drill units (MODUs) (Figure 10) will
be employed in order to provide a high degree of operational and safety
contingency. A number of vessels will be employed to provide support and
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
xiii
emergency cover for the operations, including supply boats, support vessels
and ice breakers. A ‘wareship’ will provide offshore storage and contingency
accommodation, with helicopters and fixed wing aircraft used to transfer
personnel to and from the field area, the support facilities and the
international airport at Kangerlussuaq. Existing onshore facilities at Nuuk,
Aasiaat, Sisimiut and Ilulissat will be utilised for material lay down, helicopter
operating base, handling of some wastes, supply of fuel, water and materials
and limited onshore accommodation for up to 12 project personnel.
The two MODUs are the Stena Forth, a modern drill ship designed to work in
deep water and harsh conditions including broken ice, and the Stena Don, a
dynamically-positioned semi-submersible drilling unit also designed for work
in harsh environments. As both MODUs remain on station using thrusters
there is no requirement for anchoring during normal operations.
Figure 10 Stena Forth Drillship and Stena Don Semi-Submersible Drilling Rig
Source: Photo courtesy of Stena
The planned drilling depths are between 3,000 and 4,000m below seabed. The
drilling process uses drilling bits of different sizes to drill a series of holes
from the seabed to the planned well depth. Water based muds will be used as
drilling fluids which will be circulated inside of the drill string to the bit in
order to remove cuttings and maintain stability. Although mainly water
(around 75%), for the muds to work effectively, inert substances are also
added such as barite and clays. Various other chemicals will be added to the
mud to provide the qualities required for safe and efficient drilling. The
chemicals used are assessed against international standards and ranked
according to potential toxicity. The Project plans to use only substances
categorised as those which Pose Little Or No Risk (PLONOR) to the Marine
Environment, or that are ranked in the least potentially harmful hazard band
(Gold or E).
Rock cuttings from the drilling process will be circulated back to the drilling
unit where the muds are separated for reuse and the treated cuttings are
discharged to sea. Between 500 and 740 m3 of cuttings are expected to be
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
xiv
produced from each well. Modelling has shown that the majority of cuttings
will be deposited within 300-800 m of the well location, with bottom
deposition greater than 1 mm extending less than 200 m from each site. Once
each section of the hole has been drilled, the drill string will be lifted out and
casing will be lowered into the hole and cemented into place. At the end of
the drilling programme the used muds will be discharged to sea.
If drilling results indicate the presence of hydrocarbons, the wells may be
tested. Testing is used to establish reservoir and fluid characteristics such as
pressure and flow rate. If required, there will be a controlled flow of
hydrocarbons back to the drill unit where they will be tested and flared. The
likelihood of flaring being undertaken is estimated at less than 6% per well. If
flaring is carried out it will involve an estimated 48 hrs of flow time spread
over 5 days, with the total volume flared from each well estimated at around
30,000 barrels of oil, or 80 million cubic feet of gas. Any flaring will require
permitting by the Greenland authorities and will be monitored for signs of
incomplete combustion. An oil recovery vessel with full dispersant capability
will be on standby throughout the process.
Following completion, the wells will be plugged and suspended. Each well
will have an industry standard wellhead at the surface, with a protective cover
to prevent damage to or from the wellhead due to snagging or collision. Once
all wells have been drilled, the MODUs and support vessels will demobilise to
their next job or home base.
SUMMARY OF IMPACTS AND MITIGATION
The proposed exploration activity has the potential for sources of noise and
atmospheric emissions, as well as physical disturbance and a variety of
discharges and wastes. Those sources identified in this assessment are typical
of drilling activities in waters around the world. There are no unusual or
unique emissions, discharges or other potential sources of environmental
impact. A detailed study of the potential impacts, sensitivity of receptors,
mitigation measures and any residual impact has been carried out and is
included within the EIA report. An overview of the main areas of impact,
related operations and mitigation measures is shown in Table 2 below.
Table 2 Summary of Main Impact Areas, Operations and Mitigation Measures
Potential
Impact
Source of Impact / Area
of Operations
Mitigation Measures
Disruption
to other sea
users
Mobilisation, the 500m
exclusion zone around
drilling operations and
vessel movements to and
from the Project areas.
• Early and ongoing consultation with local communities,
authorities and other key stakeholders. Use of support
vessels to alert other marine craft of the operations.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
xv
Potential
Impact
Source of Impact / Area
of Operations
Mitigation Measures
Seabed
impacts
Entry of the drill bit and
cuttings discharged from
the drilling process.
• Anchoring has been avoided by using DP drilling units.
• The seabed has been studied and sampled to establish
the baseline environment. No benthic habitats or species
were identified which have limited distribution or are
considered to be rare or protected.
• Cuttings will be cleaned before being discharged and
dispersion has been modelled to show the extent of
seabed impact from the accumulation of cuttings.
Noise Underwater noise from
drilling and the
movement and
positioning of the
MODUs and vessels.
Airborne noise from
plant and machinery,
plus helicopter and
aircraft movements.
• Regular maintenance programme for plant and
machinery.
• Noise levels are not high enough to cause harm to
marine life and any behavioural response is expected to
be temporary and short term.
• Any use of a seismic source for well testing will follow
industry best practice to minimise disturbance to marine
mammals.
• Helicopter travel will be planned taking into account
sensitive coastal areas and periods to minimise
disturbance.
Air quality Combustion emissions
from plant and
machinery on the
MODUs and vessels.
Emission to air from
aircraft movements.
Emissions to air from
potential well test
flaring.
• Regular maintenance programme for plant and
machinery.
• Use of arctic grade low sulphur fuel to reduce emissions.
• Probability of flaring estimated at less than 10% per
well. Any flaring will be for a limited period (estimated
at 48 hours over 5 days) and will be closely monitored
with spill response vessels on standby.
Water
quality
Discharges of ‘domestic’
drainage and sewage
from the MODUs and
vessels.
Discharge of organic
food waste offshore.
Discharge of cuttings
during drilling and
release of drilling mud at
the end of drilling.
Use of chemical
additives in the mud.
• Sewage, grey water and kitchen waste will be treated,
handled and discharged according to MARPOL
standards.
• Bilge and drainage water will be treated to MARPOL
standards (< 15ppm oil in water).
• Drilling will use only water based muds.
• All chemicals will be registered according to
international standards and the least impacting
chemicals selected which will do the job.
• Cuttings will be treated to remove mud for reuse.
• Any oil on cuttings from the formation will be separated
on the drilling unit. No oil on cutting will be discharged
over the side if it will result in an oil sheen on the
surface
Waste Routine drilling
operations will produce
a range of hazardous
and non-hazardous
wastes.
Limited waste will also
be produced from
vessels and onshore as
part of the support
operations.
• All solid wastes will be transferred to a registered waste
management contractor for disposal at appropriate
licensed facilities. No waste materials, other than
cuttings and food waste, will be discharged to sea.
• All wastes will be managed and disposed of according
to the Waste Management t Plan, the Duty of Care and
relevant legislation.
• Waste oil from any unplanned event will be disposed of
in accordance with the Oil Spill Plan.
ENVIRONMENTAL RESOURCES MANAGEMENT CAPRICORN GREENLAND EXPLORATION-1
xvi
Potential
Impact
Source of Impact / Area
of Operations
Mitigation Measures
Oil spills
and
unplanned
events.
A major unplanned
event such as a blow-out
may release large
quantities if crude oil
into the environment.
Storage and refuelling
incidents may also cause
the release of fuel or
chemicals into the
environment.
• Two rigs are being used in order to provide contingency
capability for relief well drilling.
• Oil spill modelling has been carried out and a detailed
oil spill contingency plan implemented.
• In the case of a well control incident, the well will be
closed in at the Blow-Out Preventer (BOP).
• Operating procedures are in place for fuel and material
transfers and onboard storage of hazardous materials.
• An ice management plan will be adopted to help
minimise the risk of collision with icebergs.
• Refuelling operations will be conducted in calm weather
conditions and closely monitored.
The mitigation measures outlined in the EIA and the overall Project Plan are
the result of extensive industry experience with offshore exploration drilling,
and are tried and tested. Furthermore, the management systems required to
implement such measures are well understood and known to be effective.
There is, therefore, a high level of confidence that potential effects will be
reduced to levels As Low As Reasonably Practicable (ALARP) through the
successful implementation of the management and mitigation measures
detailed herein.