A Synopsis of Nova Scotia`s Offshore Oil and Gas Environmental

Transcription

A Synopsis of Nova Scotia’s Offshore Oil and Gas
Environmental Effects Monitoring Programs
Summary Report
March 2011
A Synopsis of Nova Scotia’s Offshore Oil and Gas
Environmental Effects Monitoring Programs
Summary Report
March 2011
Table of Contents
1. INTRODUCTION ........................................................................................................................................ 1
3. COPAN PRODUCTION ACTIVITIES............................................................................................................. 2
3.1 Shellfish tainting studies ..................................................................................................................... 3
3.2 Benthic sampling studies .................................................................................................................... 3
3.3 project decomissioning monitoring .................................................................................................... 4
3.4 COPAN Summary ................................................................................................................................ 4
4. SOEP PRODUCTION ACTIVITIES ................................................................................................................ 4
4.1 Water Quality ...................................................................................................................................... 5
4.2 Sediment Quality (chemistry and toxicity).......................................................................................... 5
4.3 Benthic Habitat Quality ....................................................................................................................... 6
4.4 Taint, Chemical Body Burden and Fish health .................................................................................... 7
4.5 Marine Mammals and Underwater Noise .......................................................................................... 7
4.6 Seabird Monitoring, Beached Seabird Surveys and Air Quality .......................................................... 7
4.7 SOEP summary .................................................................................................................................... 8
5. SEISMIC SURVEY ACTIVITIES..................................................................................................................... 8
5.1 (2003) Corridor Resources’ 2-D Seismic Program off Western Cape Breton, Nova Scotia. ............. 10
5.2 (2003) Marathon Canada Petroleum’s 3-D seismic program on the Scotian Slope ........................ 10
5.3 (2003) Encana corporation’s stonehouse 3-d seismic survey near Shortland and haldimand
canyons ............................................................................................................................................. 12
5.4 (2005) Hunt Oil Company of Canada’s 2006 Seismic Survey in Sydney Bight. ................................. 12
5.5 Seismic Summary .............................................................................................................................. 13
6. EXPLORATORY DRILLING ACTIVITIES ...................................................................................................... 13
6.1 Panuke H-08 ...................................................................................................................................... 14
6.2 H-23 Newburn ................................................................................................................................... 14
6.3 Exploratory Summary ....................................................................................................................... 15
7. DISCUSSION AND CONCLUSION ............................................................................................................. 15
8. REFERENCES ........................................................................................................................................... 17
LIST OF ACRONYMS:
BBL – Benthic boundary layer
CEAA – Canadian Environmental Assessment Act
COPAN – Cohasset- Panuke project
DFO - Department of Fisheries and Oceans
EA – Environmental Assessment
EC – Environment Canada
EEM – Environmental effects monitoring
EIS – Environmental impact statement
EPP – Environmental Protection Plan
ESRF – Environmental Studies Research Fund
LTMO – Low toxicity mineral oil
MPA – Marine protected area
OBM – Oil based mud
OWTG – Offshore Waste Treatment Guidelines
PW – Produced water
RA – Responsible Authority
ROV – Remote operated vehicle
SBM – Synthetic based mud
SOEP – Sable Offshore Energy Project
TPH - Total petroleum hydrocarbon
GLOSSARY OF TERMS
Amphipod - any marine or freshwater crustacean of the order Amphipoda , such as the sand hoppers, in
which the body is laterally compressed.
Benthic - Relating to the bottom of a sea or lake or to the organisms that live there.
Benthic boundary layer - The layer of water directly above the sediment at the bottom of a river, lake or
sea. It is generated by the friction of the water moving over the surface of the substrate.
Chemical body burden - The build-up of synthetic chemicals and heavy metals in living bodies, which
can have negative health effects.
Epibenthic - The organisms living on the surface of the sea bed.
Epifaunal - Aquatic animals that live on the bottom substratum as opposed to within it, that is, the
benthic fauna that live on top of the sediment surface at the seafloor.
Fauna - All of the animal life of any particular region or time, a opposed to plant life.
Infaunal - Aquatic animals that live in the substrate of a body of water, especially in a soft sea bottom.
Macrofauna – Benthic or soil organisms which are retained on a 0.5mm sieve. Studies in the deep sea
define macrofauna as animals retained on a 0.3mm sieve to account for the small size of many of the
taxa.
Moored shellfish – Caged shellfish, typically bivalves, moored in a fixed location and possibly at various
depths. Used to measure animal health in the receiving environment
Taint - a trace of an undesirable coloration or taste in an organism
CNSOPB 2009: A Synopsis of Nova Scotia’s Offshore Oil and Gas EEM Programs - Summary Report
1. INTRODUCTION
The Canada-Nova Scotia Offshore Petroleum Board (CNSOPB) is responsible for ensuring Operators
implement programs that provide for protection of the environment during all phases of offshore
petroleum activities, ensuring that environmental hazards are properly identified and that the
associated risks are assessed, mitigated and managed. Environmental Effects Monitoring (EEM) for
offshore petroleum activities in Nova Scotia involves scientific monitoring of the effects of production
activities, and occasionally exploration activities, on specific components of the surrounding
environment. Production program EEM is conducted annually, with the design reviewed and adapted
from year to year. Known or suspected project effects are monitored by measuring contaminant levels,
through laboratory analysis that determine toxicity in order to define their relationship with receptors in
the marine environment.
Understanding the relationship between potential effects and the ecosystem, through ongoing EEM,
provides knowledge for the implementation of management strategies that identify and mitigate
effects. This knowledge provides for responsive decision making by operators, part of what is known as
adaptive management. Adaptive management can be described as a ‘learn by doing’ approach that
incorporates changing science, methods, results, and industrial practices into subsequent management
decisions. As a result, management processes that adhere to adaptive principles not only focus on
achieving objectives but also add to the collective knowledge base about an ecological system,
improving the precision and efficacy of future decision making and the regulatory process. As each
monitoring program goes through a cycle of data collection, interpretation, analysis, and review, new
information is often discovered leading to altered monitoring parameters. With ongoing monitoring
programs the cycles repeat on an annual basis creating a reiterative process by which management
efforts are adjusted in order to reflect ongoing results of the program and the needs of the ecological
system being examined. Many of the EEM reports submitted to the CNSOPB are part of such a process
and others are single event reports that still form part of the larger EEM picture that adds to the ‘learn
by doing’ approach.
Operators must receive authorization from the CNSOPB before any petroleum related activities are
conducted in the offshore area. Certain activities may also require authorization from Fisheries and
Oceans Canada (DFO) and Environment Canada (EC). An environmental assessment (EA) must be
submitted to the CNSOPB as part of an application for authorization of an activity offshore Nova Scotia.
Since the CNSOPB is a federal authority under the Canadian Environmental Assessment Act (CEAA), all
EAs for petroleum activities are undertaken in accordance with the CEAA. EAs are a tool used by the
CNSOPB to assess the impact of proposed activities through specific predictions of environmental
effects. Some of these predictions are later verified using EEM programs designed to collect data on the
known relationship between activities and the receiving environment.
An EEM process framework was developed by the CNSOPB, in conjunction with the Canadian
Environmental Assessment Agency, Fisheries and Oceans Canada (DFO), and Environment Canada, in
order to strengthen cooperation and coordination between government, regulators and industry when
conducting EEM programs for the offshore oil and gas sector. One of the responsibilities outlined in the
EEM framework is “to periodically provide a synopsis report of each active EEM program to senior
management and the public”. As part of that responsibility, this publication will summarize EEM
programs conducted for three different types of offshore activities; production, seismic surveys, and
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exploratory drilling. The accomplishments of EEM programs will be discussed in order to create a
general picture of past efforts and provide context for future programs.
2. EEM METHODOLOGY
Monitoring programs may use various methods to test for predicted project effects outlined in an EA.
The EA identifies several valued ecosystem components that are later monitored for predicted changes
using various assessment and observation tools that may also attempt to gauge the spatial extent of any
determined effects. For instance, methodologies used offshore Nova Scotia include:
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Monitoring of produced water effects is through chemical characterization tests, Sea Urchin
Fertilization tests, and toxicological tests such as the Microtox test.
Water column monitoring is conducted by taking live shellfish samples directly from platform
legs or moored cages and then using a sample homogenization process to conduct body burden
hydrocarbon analysis.
Sediment chemistry monitoring involves retrieving samples with a damped slow corer from the
seabed, to ensure the sediment-water interface is intact. The same samples are used for
amphipod mortality testing to determine possible toxicity in sediments.
Seabird monitoring consists of relatively continuous and opportunistic observations from
platforms and project vessels using trained observers.
Sampling design is also an important part of EEM programs to assess the extent and range of possible
effects. As previously mentioned, monitoring parameters may change from year to year as the EEM
programs adapt to better understand findings from past surveys. For instance, a study may change
sample sites to move its focus closer to a predicted source of contamination if subsequent surveys did
not find predicted effects in predetermined ranges and areas. However, the actual laboratory methods
are less likely to change over time in order to ensure data consistency.
3. COPAN PRODUCTION ACTIVITIES
Nova Scotia’s first offshore oil program, The Cohasset-Panuke Project (COPAN), began production in
1992 and finished in 1999 after producing 44.5 MMBbls. Initially, project drilling was completed in
1993, however intermittent drilling continued from 1996 to 1999 in order to maintain production levels.
EEM programs for production activities during the COPAN offshore project reflect earlier practices and
standards adopted to protect the marine environment by industry, regulators, and government.
Therefore it is also important to note that such practices and standards reflect the prevalent
environmental concerns and thinking of the time, in many ways serving as both precedent and
predecessor for the larger SOEP EEM programs that followed. Figure 1 illustrates the location of both
the SOEP and COPAN production projects. The COPAN EEM programs consisted of shellfish tainting
studies and benthic sampling, and ran from 1993 - 1999.
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Figure 1: Location of Production Projects
3.1 SHELLFISH TAINTING STUDIES
COPAN shellfish tainting studies employed moored shellfish programs, during the project’s original and
ongoing drilling programs, and compared near-field observations with far-field control samples. While
petrogenic hydrocarbons were detected in samples at 500 m and 1000 m, tainting effects were only
observed from samples taken within 500 m at Cohasset in pre-1998 surveys. As well, the petroleum
product produced during this project, Scotian light crude oil, was not indicated in the tainting found to
occur. No tainting effects were found in the 1998 and 1999 studies.
3.2 BENTHIC SAMPLING STUDIES
Baseline benthic density and diversity appeared similar to post-drilling assessments, indicating no
significant project effects on benthic macrofauna. In a 1993 post-drilling survey, only one sediment
sample site detected petrogenic hydrocarbons at Cohasset 250 m. A post-operational survey published
in 2000, found petrogenic hydrocarbons at 50 and 100 m, but not 250 m. This survey also conducted
significant video monitoring at most near-field sample sites and observed typical species composition,
for an environment generally considered as barren, despite evidence of hydrocarbon contamination
within 100m from well sites.
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3.3 PROJECT DECOMISSIONING MONITORING
The environmental assessment conducted for the decommissioning of COPAN predicted that flowlines
and some sub-sea infrastructure could be left safely buried on the seafloor following abandonment of
the project. Post-project monitoring continued until 2005 and determined that the original EA
predictions were correct and that no sub-sea infrastructure posed a risk to the environment or the
fishing sector. Abandoned parts of the COPAN installation where still safely buried as of 2005.
3.4 COPAN SUMMARY
COPAN EEM tested for traces of both low toxicity mineral oil (LTMO) and Scotian light crude. Failure to
find the latter, in taint testing results, may have helped to isolate LTMO as a target for mitigation. LTMO
and cuttings discharges were reduced to zero after 1998, through the use of reinjection technology that
sequestered drill wastes below the seafloor. COPAN environmental studies also demonstrated that
moored shellfish can be used as an in-situ monitoring tool, a practice that was employed during early
SOEP EEM programs.
4. SOEP PRODUCTION ACTIVITIES
Sable Offshore Energy Project (SOEP) is an offshore petroleum production activity operated by
ExxonMobil Canada Properties (ExxonMobil). The project effects are evaluated by monitoring important
components of the receiving environment. The following paragraphs summarize the results of SOEP
EEM programs from 1998 to 2008 by selected environmental components. Categorizing the receiving
environment into selected environmental components is a method for isolating and monitoring possible
effects. Monitoring sites are arranged within a sample grid, as illustrated below in figure 2, which shows
the 3 SOEP tier 1 production fields. Not shown are the SOEP tier 2 production sites, Alma and South
Venture, which came online in 2003, and 2004 respectively.
Figure 2: EEM sample grids for SOEP tier 1 production sites. (Source: SOEP 1999)
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With the approval of the CNSOPB and in consultation with DFO and EC, some environmental
components within the EEM programs have been dropped, added or altered by ExxonMobil from year to
year based on monitoring priorities, new project developments, and monitoring strategies generated
from previous EEM cycles. SOEP annual EEM programs report that effects have been less than
predictions made in the 1996 Environmental Impact Statement (EIS) and have contributed to an
expanding base of scientific knowledge regarding the relationship of SOEP activities and the unique
Sable offshore environment.
4.1 WATER QUALITY
Water quality monitoring has seen several changes from 1998 to 2008, moving from an initial focus on
water column and benthic boundary layer (BBL) quality concerns during drilling, to produced water (PW)
monitoring during the production phase. The 1998 assessments were concerned with a predicted
plume of drilling wastes and flocculent in a gradient spreading outward from the platforms. However,
the 1999 EEM program found no flocculated drill waste or detectable concentrations of petrogenic
hydrocarbons outside the 500m safety zone during the drilling phase, and was able to observe the
predicted plume only once out to 500 m from Venture. With the transition from drilling to production
phases, drilling was less frequent and water quality monitoring began to focus on the effects of
produced water (PW) in 2000. From 2000 to 2008, monitoring of the PW stream on the installation
confirmed relatively low toxicity pre-discharge, with an increasing trend from 2005 to 2008. However,
released PW, into the ocean, is highly diluted within 5m of the discharge caisson. During the entire
production phase to date, no toxic results were observed in water column samples collected adjacent to
the platform. Despite the increasing low toxicity trend, SOEP PW is still within the safe discharge criteria
detailed in the Offshore Waste Treatment Guidelines (OWTG). Concentrations of oil in produced water
from SOEP are relatively lower than other east coast operations and discharge volumes are significantly
less. Generally, natural gas production generates less PW and oil-in-PW than the production of crude
oil.
4.2 SEDIMENT QUALITY (CHEMISTRY AND TOXICITY)
Sediment quality monitoring and toxicity testing from 1998 to 2007 focused on a set of 24 metal
chemical parameters, total petroleum hydrocarbon (TPH), and barium. Monitoring has consistently
found all 24 parameters unchanged from the 1998 baseline surveys and less than predicted than in the
EIS , with the exception of TPH and barium concentrations found to elevated above background levels.
The main source of elevated TPH and barium concentrations are the drill waste and cuttings piles
deposited on the seafloor following drilling activities. These discharges are composed of drilling fluids
and materials removed from below the seafloor during the drilling process. In 1999, elevated TPH and
barium concentrations were originally found at all platforms. Since then the spatial extent of
contamination has decreased with none detected at Venture from 2000 onward, and at North Triumph
from 2003 onward. Cuttings piles dispersed more quickly than predicted at North Triumph and figure 3
shows the extent of elevated TPH and Barium at Venture. Elevated concentrations at Thebaud have
decreased slowly, with only barium being detected above background concentrations out to 250 m in
2007. In addition, sampling sites on the western boundary of The Gully MPA have shown no elevated
concentrations of contaminants since monitoring began and provide no evidence of drilling waste
reaching the area. The SOEP annual EEM reports note that amphipod mortality testing was found to be
the most consistent indicator of sediment toxicity and correlated contamination results from 1998 to
2001. After 2001, sediment toxicity was only found with this method at Thebaud’s near-field 250 m
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sampling site in the direction of the prevailing current. However, the Thebaud site stabilized to
background concentrations the following year and no toxic responses have been observed at any site
since 2003. Sediment quality monitoring has shown the effects of SOEP drilling and production activities
to be far less than EIS predictions, demonstrating no organic or inorganic contaminants other than TPH
and barium.
Figure 3: Range of elevated TPH and Ba concentrations in Sediment quality monitoring.
4.3 BENTHIC HABITAT QUALITY
Benthic habitat monitoring from 1998 to 2007 was initially concerned with changes in species
abundance as an indicator of quality and eventually incorporated fish density surveys starting in 2005.
Benthic monitoring since 1998 has demonstrated no obvious effect beyond the drill waste piles on fauna
or habitat, and no significant effect on epifaunal or infaunal communities at any sampling station.
Beginning in 2000, video surveys began to show the existence of diverse epifaunal communities.
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Crabs, mussels, sea cucumbers, sea stars, sea urchins, anemones and other species were observed each
year, culminating with a realization that 2002 data demonstrated a 10 fold increase in habitat gain over
habitat originally lost during drilling and field construction, representing 4 times the expected gain:loss
ratio. Fish density surveys starting in 2005 showed large schools of cunners and Atlantic cod near the
Thebaud platform and did not find any species at risk aggregating in the area. Each EEM program has
demonstrated an increase in biomass and potential growth related to maturing communities of marine
species. The most recent ROV survey conducted in 2008 found large numbers of sea cucumbers thriving
on the pipeline which was also found to support various other species across several trophic levels,
indicating the presence of an established food web.
4.4 TAINT, CHEMICAL BODY BURDEN AND FISH HEALTH
Taint and body burden monitoring was initially focused on observed tainting effects, as a result of the
predictions in the EIS. However, throughout monitoring, no tainting effects were observed in the far
(greater than 1000m), mid (500m) and near-field (250m) sampling sites. In fact, efforts to find tainting
moved inward from far-field to mid and then to the near-field. Later surveys targeted the safety zone
area directly adjacent or under platform structures, where tainting was only encountered once in Jonah
crabs collected directly from the platform stucture at Venture. Although hydrocarbons were detected in
moored mussels and natural scallop beds within 500 m from Venture, observed concentrations were
within natural variations and in 2003 were less than concentrations found in commercial samples used
as a control group. The SOEP 2007 EEM report states that mussel testing found no petrogenic
hydrocarbon indicators and that the hydrocarbons that were found in samples had a profile typical of
those produced by naturally occurring phytoplankton. As well, sampled mussels occasionally tasted
better than commercial samples in sensory tests and the 2001 program found Snow crabs collected
adjacent to North Triumph showed no difference in taste or odor compared to samples captured 20 km
away. A fish health survey was temporarily adopted for 2005 but was not included in future programs
after it found no health effects in Atlantic cod outside of regional variations and revealed no major
indicators of petrogenic effects on fish health. Throughout the EEM program, taint effects were not
observed as predicted in the EIS.
4.5 MARINE MAMMALS AND UNDERWATER NOISE
Marine mammal monitoring has been conducted regularly throughout drilling and production phases
and starting in 2005 heightened efforts were made to search for and gauge the extent of possible noise
pollution from project activities. No evidence of avoidance or attraction to project structures or vessels
has been noted since the commencement of drilling activities. As well, marine mammals have been
observed within radiating sound spectra near platforms where noise levels can possibly cause behavioral
effects, however no abnormal effects have been noted to date. Increased monitoring took place in The
Gully in 2005 and showed project originated noise pollution is well below ambient noise levels by the
time it reaches The Gully Marine Protected Area (MPA).
4.6 SEABIRD MONITORING, BEACHED SEABIRD SURVEYS AND AIR QUALITY
Seabird monitoring efforts from 1998 to 2007 have observed little to no effect on birds transiting to and
from Sable Island or the Scotian Slope. No abnormal seabird fatalities have been observed anywhere in
the project area and observations match population trends for the region. Beached seabird testing has
revealed no mortalities connected with substances typical of offshore gas activities, except for one
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sample collected on one monthly survey (2006) out of many surveys conducted over eight years. From
1998 to 2006 Seabirds were not observed to be attracted to platform structures or lights; however in
2007 number of land-based birds did die due to collision with platform superstructures as well as a DFO
vessel on which seabird surveys were being conducting on the eastern Scotian Shelf. Environment
Canada air quality surveys conducted on Sable Island to date have not been able to demonstrate an
effect related to SOEP activities but have been able to demonstrate the long-range transport of
contaminants from onshore sources.
4.7 SOEP SUMMARY
SOEP EEM annual programs report that the adverse effects of production activities have consistently
been less than EIS predictions. SOEP EEM programs to date demonstrate a functioning process through
which monitoring resources have been adaptively applied to areas of possible concern. A combination
of proper mitigation of predicted effects before they were present and growing knowledge of the
unique Sable offshore environment help explain the consistent differences between predictions and
observed effects. Better mitigation, and increased learning about the relationship between production
activities and the receiving environment, is the measure of success for the EEM process.
Differences between SOEP and COPAN activities, in regards to environmental effects, may reflect
operational differences between the two projects such as the use of low toxicity mineral oil (LTMO)
based mud at COPAN, compared to the use of water based and synthetic based muds (SBMs) at SOEP.
5. SEISMIC SURVEY ACTIVITIES
The following section summarizes several EEM reports for four seismic surveys conducted in the
province’s offshore area from 2004 to 2006. The EEM programs for seismic surveys generally focus on
observing valued marine species, in this case marine mammals, snow crab, and Atlantic cod. An
important component of such programs is acoustic monitoring, where produced sound levels are
measured and recorded with the intention that they may be correlated with animal observations at a
later date. Monitoring and possibly correlating produced sound with animal observations can increase
the capacity to measure, mitigate, and manage potential seismic survey effects. Figure 4 demonstrates
the marine mammal safety zone, which can be altered to suit the characteristics of the seismic
operation or receiving environment. Air guns are the sound source, and seismic cables contain recording
hydrophones that collect reflected sound waves stream behind.
Figure 4: Seismic survey vessel and 500m safety zone.
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In areas under the jurisdiction of the CNSOPB, seismic programs must adhere to the “Statement of
Canadian Practice with Respect to Mitigation of Sound in the Marine Environment”, which complements
existing environmental assessment processes. The Statement specifies the mitigation requirements that
must be met during the planning and conduct of marine seismic surveys, in order to minimize impacts
on life in the oceans. These requirements are set out as minimum standards, which will apply in all nonice covered marine waters in Canada.
Figure 5: Seismic surveys reviewed in EEM Summary
While this section summarizes four seismic programs, illustrated in figure 5, each program has separate
monitoring reports focusing on specific components. These separate reports represent the diverse
challenging nature of examining the relationship between seismic activities and the receiving
environment, which industry has addressed by attempting to isolate important variables in these EEM
programs. Seismic survey environmental effect monitoring is a relatively new activity. Therefore,
seismic monitoring programs to date do not fit the ideal form of EEM and are often exercises in
expanding our knowledgebase in order to develop a better seismic EEM regime for the future.
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However, the programs described in the following paragraphs do help to form part of the larger EEM
picture for offshore petroleum activities.
5.1 (2003) CORRIDOR RESOURCES’ 2-D SEISMIC PROGRAM OFF WESTERN
CAPE BRETON, NOVA SCOTIA.
July 2004 – “Acoustic Monitoring of corridor resources Inc. 2003 2-D Seismic Program Off Western
Cape Breton, Nova Scotia” by JASCO Research Ltd.
In December 2003, Geophysical Service Incorporated (GSI) conducted a 2-D seismic program for Corridor
Resources Inc. 20 km off western Cape Breton, in the Gulf of St. Lawrence. Monitoring for possible
effects of the seismic program was conducted in consideration of an abundant and lucrative snow crab
population found in this area, which is also part of the larger spawning and nursery area provided by the
southern Gulf of St. Lawrence. Fisheries and Oceans Canada (DFO) implemented a concurrent study
consisting of caged snow crabs placed within and outside the seismic survey area. JASCO Research Ltd
was contracted to acoustically monitor the horizontal extent of sound pressure levels, the range of
maximum sound levels, far-field sound levels, and sound levels measured at the caged snow crab
sample sites.
During this seismic survey, the above data was included in an industry-government study and report
titled: “Potential Impacts of Seismic Energy on Snow Crab”. This report evaluated the studies conducted
on caged snow crabs fixed in the seismic survey area. The report found no direct evidence of behavioral
or health effects on tested snow crab as a result of seismic air gun exposure. Lab results did find some
variations between organ health and embryonic development between test and control animals.
However the report notes that such findings could be attributable to a range of different variables
observed between control and test sites, such as temperature, currents, substrate, organic material
concentrations, and in-field sample handling.
5.2 (2003) MARATHON CANADA PETROLEUM’S 3-D SEISMIC PROGRAM ON THE
SCOTIAN SLOPE
August 2004 – “Marine Mammal Monitoring of Marathon Canada Petroleum’s 3-D Seismic Program
on the Scotian Slope, 2003” by LGL Ltd.
In the late spring, summer, and early fall of 2003, LGL Limited conducted a monitoring and mitigation
program for Marathon Canada Petroleum’s 3-D seismic program on the Scotian Slope. This monitoring
was conducted in consideration of the various marine mammal species that inhabit the area and the
potential for seismic projects to affect them. Two primary components of monitoring were acoustic
measurements and ship-based observations. Their objectives were to detect possible effects, mitigate
effects, address data gaps, answer questions about potential effects to mammals in the area, and
address stakeholder and regulator concerns. Using predicted and observed acoustic levels resulted in a
seasonal starting location strategy, airgun safety zones, and other operational procedures intended to
mitigate potential effects. Observations from the seismic vessel showed relatively small zones of
avoidance around the operational area for baleen and toothed whales, while little or no avoidance by
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dolphins was observed. Program data also added to knowledge of baleen whale, dolphin, and large
toothed whale distribution on the Scotian Slope.
September 2004 – “Acoustic Monitoring of Marathon Canada Petroleum ULC 2003 Cortland/Empire 3D Seismic Program” by JASCO Research Ltd.
The main objectives of this acoustic monitoring program were to verify and validate pre-program
acoustic modeling, document underwater sound production, and to determine sound distribution in the
receiving environment. In-field acoustic monitoring resulted in safety zones being expanded beyond
original modeling predictions that determined the zone. Acoustic noise levels received in The Gully MPA
were lower than levels known to cause behavioral changes in marine mammals. Additionally, data on a
seasonal surface sound channel effects in the area were collected and scientific knowledge of the sound
receiving characteristics of the Scotian Slope was increased.
2005 – “Acoustic Monitoring and Marine Mammal Surveys in The Gully and Outer Scotian Shelf Before
and During Active Seismic Programs.” An ESRF report edited by K. Lee, H. Bain, and G. Hurley.
This document is a collection of academic research papers compiled as part of the Gully Seismic
Research Program conducted during Marathon Canada Petroleum’s 2004 3-D Seismic Program, and
EnCana`s 2003 Stonehouse 3-D Survey. Research focused on seismic sound levels, mammal behavior,
vocalizations, and distributions relative to seismic surveys. The findings of the overall study and its
various papers indicate:
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The importance of simultaneous visual and acoustical observation, before, during, and
after exploratory surveys.
Industry, third-party contractors, and DFO scientists collaborated effectively and
shared data.
Enhanced mitigation and near-field monitoring were successfully conducted and “over
and above” industry standards as a precautionary approach.
No seismic operations were shut down due to acoustically observed incursions into
the safety zone by marine mammals
No indication that endangered species were impacted by Marathon’s or EnCana’s
seismic program.
Data was collected to improve noise propagation modeling predictions in the form of
acoustic signatures of seismic impulses.
Seamap Passive Acoustic Cetacean Monitoring System (SPACMS) proved a valuable
companion tool to visual observations.
The predictability of ocean bottom seismic acoustic levels is not accurate as levels
recorded were higher than modeled.
Progress was made towards developing a neural network that can identify acoustic
signatures of endangered mammals.
Hydrophones demonstrated that whales did not abandon The Gully area when seismic
vessels were 30 km away or farther.
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5.3 (2003) ENCANA CORPORATION’S STONEHOUSE 3-D SEISMIC SURVEY NEAR
SHORTLAND AND HALDIMAND CANYONS
2003 – “Marine Mammal Monitoring and Seismic Source Signature analysis: Report on EnCana’s
Stonehouse 3-D Seismic Survey 2003.” By Potter, Chitre, Seekings, and Douglas, SeaMap Ltd.
A visual and acoustic marine mammal monitoring and mitigation program was conducted by EnCana
during their 2003 Stonehouse 3-D Seismic Survey. Acoustic observations were conducted with the
SeaMap Passive Acoustic Cetacean Monitoring System (SPACMS). No adverse reactions or marine
mammal incidents were reported. During seismic acquisition, the number or marine mammals in
observable distance (1-2km) showed no change, however the animals observed did avoid close ranges
to the array (less than 100m), were observed in larger groups and appeared less vocal. However,
researchers noted that these observations could have been affected by the use of data from both
toothed and baleen whales whose behaviours may have been different to start with.
5.4 (2005) HUNT OIL COMPANY OF CANADA’S 2006 SEISMIC SURVEY IN SYDNEY
BIGHT.
November 1, 2006 – “Results from the Environmental Effects Monitoring Program of a Seismic Survey
in Sydney Bight conducted in November, 2005” prepared for Hunt Oil Company of Canada, Inc. by CEF
Consultants Ltd.
An EEM program was conducted during a seismic survey conducted by Hunt Oil Company of Canada, Inc,
in Sydney Bight in November of 2005. While other reports have been prepared as part of the EEM
program this report specifically addresses the potential sub-lethal damage to the sensitive ear structures
of fish, in this case Atlantic cod. Although the results of previous studies have raised concerns over the
sub-lethal effects of seismic air gun discharges to fish ear structures, this study aimed to identify the
distance at which such effects could occur. Suspended and bottom moored fish cages filled with
Juvenile cod were used to monitor the effects of the seismic survey vessel, the Gulf Pacific, as it passed
as close as 55m from the nearest test cage. Five cages were used at the test site, equipped with
hydrophones and video surveillance equipment. A control site consisting of two cages was also part of
the survey. All cages were collected as soon as possible once the Gulf Pacific had passed and samples
were transported to the University of Maryland for dissection and further study. Video analysis noted a
slight behavioral reaction when test cages were nearest to the seismic vessel and both test and control
sites observed similar levels of fish mortality upon retrieval, possibly due to the stress of handling,
exposure to large temperature changes, and erratic currents of the surrounding area. The most
important finding of this study was that there appeared to be no detectable damage to sensitive fish ear
structures or any other organs as a result of exposure to seismic air guns at ranges as close as 55m.
November 20th, 2006 – “Effects of Exposure to Seismic Air-Guns on the Ears of Atlantic Cod” prepared
for Hunt Oil Company of Canada, Inc. by Dr. Arthur Popper, Environmental BioAcoustics LLC.
This report is supplemental material for the EEM project conducted during a Hunt Oil Company of
Canada Inc. seismic survey in Sydney Bight in November 2005. Although an earlier report prepared by
CEF Consultants Ltd. outlines the project’s focus on sub-lethal effects of seismic air gun discharges to
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fish ear structures, this report is specifically addressing the actual fish ear tissue analysis undertaken by
Dr. Arthur Popper, a long-time leader in the field of bioacoustics. Dr. Popper’s main findings show that
he observed no physical damage attributable to seismic air-guns. However he also mentioned that due
to the poor condition of samples he received, there were not as many usable samples as he would have
preferred. Additionally, samples intended to indicate long-term post-exposure effects were not suitable
to analysis and could not add to scientific knowledge in the area of prolonged impacts.
5.5 SEISMIC SUMMARY
EEM programs for seismic activities in offshore Nova Scotia are usually not required unless there are
special circumstances (i.e known or suspected populations of marine mammal species at risk). Programs
conducted to date have met predictions made in their project EAs of no significant impacts. Also, these
programs have added to our understanding and appreciation of their interactions with the environment.
Operators and federal authorities now know more about the acoustic characteristic of the receiving
environment, how sound propagates, and the acoustic effects on some marine creatures. If adaptive
management is defined by a ‘learn by doing’ approach then these EEM programs can provide a list of
seismic monitoring best practices that will improve future endeavors.
6. EXPLORATORY DRILLING ACTIVITIES
Presently, EEM programs are not a statutory requirement for single exploratory offshore wells, though
the need for such programs is reviewed on a case by case basis during the environmental assessment
process. To date there have only been two follow up surveys conducted on exploratory wells and they
were both conducted and submitted by industry. The location of the wells is shown in figure 6.
13
Figure 6: Location of wells: Newburn H-23 and Panuke H-08.
6.1 PANUKE H-08
From May to June of 2000, EnCana drilled exploration well Panuke H-08 and undertook a concurrent
monitoring program to observe chemical, physical and biological features of the seafloor surrounding
the well. No data was gathered prior, or subsequent to the drilling. Similar to other production EEM
programs, this program found effects to be limited to within 500 m of the drilling rig. The program used
a gradient radial sampling strategy to measure the following parameters: hydrocarbons, metals, grain
size of sediments, sediment chemistry analysis, and epifaunal community habitat. Both barium and
total petroleum hydrocarbon concentrations were higher than controls concentrations at two sampling
stations, 50m and 100m, in the direction of the prevailing current but normal at other stations. Trace
metal concentrations were found to be within normal variation except for higher concentrations of
barium which was determined to be from nearby COPAN production drilling activities.
6.2 H-23 NEWBURN
In the pre-drilling environmental assessment for exploratory well H-23, Chevron agreed to conduct an
EEM program consisting of two visual surveys, made using a remote operated vehicle (ROV). The
14
monitoring strategy consisted of the ROV performing a pre-spud survey and making post-drilling visual
inspections along four transect lines in order to observe substrate characteristics, cuttings mound
dimensions, and epibenthic fauna. Effects monitored were less than those predicted by one order of
magnitude.
6.3 EXPLORATORY SUMMARY
Completing an exploratory well usually takes between 40 and 90 days using a mobile offshore drilling
unit. Although drilling a single exploratory well has identical possible effects as drilling a production
well, there has been less EEM follow up of offshore Nova Scotia exploration drilling because single
events are relatively short term and less intrusive than multi well developments which therefore have a
greater need for EEM validation. Findings from H-08 and H-23 were that adverse impacts were often
highly localized and very temporary due to the decreased amount of total drilling mud discharged during
single well exploratory programs.
7. DISCUSSION AND CONCLUSION
Ultimately, the EEM programs reviewed for this report depict a series of accomplishments to date, yet
also reveal new challenges for the future. Annual EEM programs for SOEP production activities have
reported observed effects to be consistently less than original EIS predictions:
• For instance, a predicted plume of drilling waste was only detected once and appeared
lighter and shorter lived than modeled.
• Perhaps one of the most notable differences between observations and predictions comes
from SOEP EEM sediment quality monitoring. Sediment chemistry studies only found
elevated TPH and Barium concentrations, not the full range of 24 metal chemical test
parameters. TPH and Barium concentrations were only found in elevated concentrations
out to 500 m and returned to baseline concentrations by 2003, at all SOEP phase 1 sites.
• SOEP production platforms were also predicted to contribute to benthic habitat quality by
creating a ‘reef effect’. Much more habitat was created that originally lost.
• As well, SOEP EEM programs to date have not found evidence of tainting effects in mussel
samples.
When SOEP EEM results are compared to earlier COPAN EEM programs a useful history of evolving
environmental management and mitigation is shown.
Although COPAN EEM evaluated fewer valued ecosystem components, and found more project related
effects than SOEP, those studies helped to isolate LTMO as the main contributor of petrogenic
contamination in the project area and started the ground work for using moored mussels as a
monitoring tool. Both of these results are important and have likely contributed to improving EEM
study designs for subsequent projects.
EEM program design for seismic activities is not as advanced as those for production activities, the
various programs to date have served as academic exercises to expand our knowledge about the
acoustic receiving characteristics of the marine environment. The knowledge base regarding marine
mammals and underwater noise continues to develop. Monitoring in combination with utilization of
best practices, adaptive management, and new applications of technology may help address
environmental monitoring challenges. Similarly, most exploration activities to date have been in
15
generally understood areas, yet future trends may see such activities expand into lesser known waters
demanding improved application of technology and enhanced EEM methods to compensate.
A combination of knowledge gained from past EEM programs and new technology and practices will
prove beneficial to upcoming offshore Nova Scotia oil and gas projects. For instance, the Deep Panuke
Project is scheduled to commence in 2011 and will be undergoing EEM program design stage, as have
past projects. However, this project’s EEM programs will be able to build on improved knowledge of the
receiving environment, demonstrated mitigation measures, and increased capacities in EEM technical
expertise and review processes.
Success in some areas of effects monitoring may naturally lead to improving the methods and processes
used to evaluate the relationship between offshore petroleum activities and the receiving environment.
Once a knowledge base concerning a particular interaction is developed, the remaining unknowns
become the new questions that guide and drive future monitoring efforts. However, examining EEM’s
accomplishments in the context of its inherent challenges, demonstrates how EEM is a constantly
evolving path towards better environmental protection. As each monitoring program has gone through
a cycle of data collection, interpretation, analysis, and review, new information has been applied to
improving program design and adapting monitoring parameters. Submission of acceptable EAs and
Environmental Protection Plans, as required for offshore activity authorization, allows a set of
predictions to be later verified using EEM programs. This process demonstrates the usefulness of
adaptive management and the ‘learn by doing’ approach in helping to protect the marine environment
today and for the future.
16
8. REFERENCES
ACCENT Engineering Consultants Inc., AMEC, and Hurley Environmen Ltd. (2005-2008 (incl.)). Annual
Reports Offshore EEM Program . Dartmouth, N.S.: Report to SOEP.
Chevron (2002). Environmental Survey of Deep Water Exploration Well H-23 Newburn. Dartmouth, N.S.:
Prepared by Jacques Whitford Environment Ltd.
CNSOPB, DFO, Environment Canada (2005). Environmental Effects Monitoring Coordination Framework.
Corridor Resources Inc. (2004). Acoustic Monitoring of Corridor Resources Inc. 2003 2-D Seismic Program
off Western Cape Breton, Nova Scotia. Halifax, N.S.: Prepared by Jasco Research Ltd.
Curran, K. J., Wells, P. G., & Potter, A. J. (2006). Proposing a coordinated environmental effects
monitoring (EEM) program structure for the offshore petroleum industry, Nova Scotia, Canada.
Marine Policy , 400-411.
DFO. (2004). Potential Impacts of Seismic Energy on Snow Crab. DFO Canada. Sci. Advis. Sec. Habitat
Status Report 2004/003.
ExxonMobil. (2004). SOEP Offshore EEM Program Review & Proposed 2005 Program. Halifax, N.S.
Gardner Pinfold Consulting Economists Ltd. (March 2009). "Economic Impact of the Nova Scotia Ocean
Sector 2002-2006". Prepared for the Government of Canada and the Nova Scotia Government.
Hunt Oil Company of Canada Inc. (2006). Effects of Exposure to Seismic Air-Guns on the Ears of Atlantic
Cod - Final Report. Calgary AB, Canada: Prepared by Arthur N. Popper, Environmental
BioAcoustics LLC.
Hunt Oil Company of Canada Inc. (2005). Results from the Environmental Effects Monitoring Program of
a Seismic Survey in Sydney Bight Conducted in November, 2005. Prepared by CEF Consultants
Ltd.
Hurley, G., & Ellis, J. (2004). Environmental Effects of Exploratory Drilling in Offshore Canada:
Environmental Effects Monitoring Data and Literature Review - Final Report. Prepared for
Canadian Environmental Assessment Agency (CEAA), Regulatory Advisory Committee (RAC).
International Association of Geophysical Contractors (IAGC). (2009, April). Marine Geophysical
Operations: An Overview. (Ver - 1).
Jacques Whitford Environment Ltd. (1999-2003 (incl.)). Annual Reports Offshore EEM Program. Report
to SOEP.
Jacques Whitford Environment Ltd. (1998). Offshore Environmental Effects Monitoring Design for
Venture and Thebaud . Report to SOEP.
Kilgour, B. W., Dube, M. G., Hedley, K., Portt, C. B., & Munkittrick, K. R. (2007). Aquatic Environmental
Effects Monitoring Guidance for Environmental Assessment Practitioners. Environmental
Monitoring Assessment , 423-436.
Lee, K. H., & Hurley, G. V. (Eds.). (2005). Acoustic Monitoring and Marine Mammal Surveys in The Gully
and Outer Scotian Shelf before and during Active Seismic Programs. Report No. 151 & 154.
Environmental Studies Research Fund.
MacLaren Plansearch . (1997). Physical fate of drilling and production effluent discharges and impact on
the marine environment - Phase A (Interim), Phase B (Final), and Phase C (The Gully) .
Marathon Canada Petroleum ULC. (2004). Acoustic Monitoring of Marathon Canada Petroleum ULC
2003 Cortland/Empire 3-D Seismic Program. Halifax, N.S. : Prepared by Jasco Research Ltd.
Marathon Canada Petroleum ULC. (2003). Marine Mammal Monitoring of Marathon Canada
Petroleum's 3-D Seismic Program on the Scotian Slope, 2003. Halifax, N.S.: Prepared by LGL Ltd.
17
PanCanadian Petroleum Ltd. (2000). Environmental Study Cohasset Panuke Fields - Final Report.
Dartmouth, N.S.: Jacques Whitford Environment Ltd.
PanCanadian Resources. (1999). Oil based muds environmental monitoring program at Cohasset:
Shellfish tainting study - 1993 to 1999 program results. Prepared by John Parsons Associates
Biological Consultants.
Sable Offshore Energy Project (SOEP). (1996). Volume 3: Environmental Impact Statement. MacLaren
Plansearch (1991).
Santos, M. F., Lana, P. C., Silva, J., Fachel, J. G., & Pulgati, F. H. (2009). Effects of non-aqueous fluids
cuttings discharge from exploratory drilling activities on the deep-sea macrobenthic
communities. Deep-Sea Research II , 32-40.
Zhou, S., Ackman, R. G., & Parsons, J. (1996). Very long-chain aliphatic hydrocarbons in lipids of mussels
(Mytilus edulis) suspended in the water column near petroleum operations off Sable Island,
Nova Scotia, Canada. Marine Biology , 499-507.
18
Canada - Nova Scotia Offshore Petroleum Board
1791 Barrington Street,
6th Floor
Halifax, N.S.
B3J 3K9

A Synopsis of Nova Scotia`s Offshore Oil and Gas Environmental

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