1. Possible Exploration Techniques:
* Seismic (land and marine, taking into consideration the three sources
for sound vibrations- dynamite, thumpers and air cannons)
* Gravity
* Magnetic
* Electrical Method
2. Possible Drilling Strategies:
* Tophole drilling
* Directional drilling
* Horizontal drilling
* Extended reach drilling
* Slimhole drilling
* Coil tubing
3. Service operations, how to get raw materials and dispose of
by-products, etc..
4. Transportaion, detailed analysis of every possible method.
5. Antennas and other methods of communication, what are the
environmental effects ?
6. The effects of accidental spills and the best way to clean them up.
______________________________________________________________________________
PART 3- Research conducted for mid-term (this has not been extensively grammatically
checked as I just used it to prepare for the mid-term), alot of this has been taken from the following website:
http://tapseis.anl.gov/
A.FACTS ABOUT THE EXISTING PIPELINE:
1. 800 miles long, 48 inch diameter.
*Buried - about 420 miles
*Aboveground - about 380 miles in areas of permafrost
2. 11 pump stations, only 7 operating.The 11 pump stations are located
at intervals of approximately 50 to 100 miles
3. Starts at North Slope 800 miles away from Port Valdez where it
terminates.
4. Crude oil produced on Alaska's North Slope.
5. In 2001 , rate was 1 million barrels per day.
6. For the 420 miles that the pipeline is above ground, it is supported
on vertical support members (VSMs), located about every 60 feet. Valves
are strategically placed along the pipeline to permit isolation of
sections of the pipeline and minimize the volume of potential spills.
7. About 75% of the pipeline corridor traverses permafrost. In areas of
unstable soil, the pipeline is elevated above ground to keep the
permafrost from melting. About 420 miles of the pipeline is elevated,
and 380 miles is buried. In particular areas, small portions of the
buried pipeline are refrigerated (total of 4 miles).
8. Above ground sections of the pipeline are built in a zig zag
configuration to allow for expansion or contraction of the pipe because
of temperature changes. The design also allows for pipeline movement
caused by an earthquake (TAPS crosses three major active fault lines).
An earthquake monitoring system provides ground motion detecting and
warning capabilities for strong events. So if any shifts (whether due to
temperature fluctuations or earthquakes) occurs, the shape of the
pipeline compensates for this shift and prevents oil spillage.
9. About 554 elevated animal crossings were created to allow large
animals to cross the pipeline without obstruction. At elevated animal
crossings, pipeline height is at least 10 feet. At 23 other locations,
the pipeline is buried to allow animals to cross; each buried crossing
is about 200 ft. wide.
B.ENVIRONMENTAL IMPACT OF THE PIPELINE:
1. Terrestrial Environment:
* Even though mitigation measures are being taken and specialized
pipelines are used to reduce the thawing of permafrost when the
pipelines are buried underground, a significant amount of permafrost
thawing persists.
* Maintenance activities, corrosion digs and construction projects for
pipeline related facilities continuously cause localized TEMPORARY land
disturbance.
* If no proper river training is applied, the pipeline can adversely
affect the behaviour of rivers.
2. Water Resources and Wastewater:
* Expanding the Trans-Alaskan Pipeline to reach ANWR means that more
pressure is going to be imposed on the water resources in order to
support operations and maintenance activities.
* The wastewater discharges are a great threat to the environment.
3. Atmospheric Environment:
* Widespread point-source emissions result in a deterioration in air quality.
4. Biological Resources:
* Vegetation and Wetlands-- There is a great loss of vegetation and
wetlands under gravel fill nad changes from water impoundments and
thermokarst.
* Fish -- Impacts on fish include obstruction of movements in low water
crossings or culverts along the pipline, injury or habitat loss from
potential oil spills, and recreational fishing harvests. Obstruction of
movements would be a continuous problem because of the dynamic nature of
the pipeline and associated water bodies. Oil spills can impact fish,
although the duration and extent of impacts are usually limited.
* Birds -- Increased predation on waterfowl by mammalian and avian
predators may occur if predator populations increase due to access to
garbage. Oil spills can also kill large numbers of birds.
* Terrestrial Mammals -- Important impacts include disturbance and
displacement from preferred habitats, mortality from roadkills,
increased predator numbers from access to anthropogenic foods, and sport
hunting. Disturbance and displacement of caribou during the calving
period is also a potential impact.
* Marine Mammals -- Important impacts include disturbance and
displacement during offshore exploration and development and mortality
or injury from oil spills.
C. MECHANISM OF THE ENVIRONMENTAL IMPACT OF THE PIPELINE - Understand what
exactly is causing the damages:
* Maintenance is often required and this, as we previously mentioned,
impacts the ground. Maintenance takes various forms:
a. Corrosion repair of below-ground mainline pipe-line.
b. slope/workpad maintenance, pipes situated in sloping areas require
more frequent check-ups and maintenance.
c. Potential pipe-line replacement.
d. Mainline Below-Ground Valve Maintenance.
e. Remedation of Mainline Cathodic Protection.
f. River Crossings and River Training Structure Repairs.
g. Surveillance Actions,
in the summer-- helicopters or four-wheel-drive trucks on the workpad
and access roads.
in the winter-- snow vehicles or helicopters.
again , this causes physical damage and pollution.
h. Fuel gas line maintenance and repair
i. New material sites/rock quarries-- basically, damages due to gravel /
rock mining needed to build the roads that will be required to operate
the pipeline.
* The second mechanism of environmental impact is spilling of oil.
* Of course, the actual building of the pipeline.
D.TWO TYPES OF ROADS POSSIBLE FOR TRANSPORTATION ASSOCIATED WITH PIPELINE:
1. Gravel Roads :
In order to build gravel roads we need to get gravel materials. In order
to do that we need to dig gravel from river beds, river beds are usually
fresh water ones so this pollutes or freshwater, or use explosion
techniques. this will deisturb the ecology of the area and any habitats
of animals as well as vegetation found in that area. The actual road
will also affect the permafrost (increased heat and pressure .. higher
chance of thawing..). Workpad and access-road embankments built over the
relatively warm permafrost will compress or disturb the vegetative cover
that formerly protected the permafrost. This would cause the ground to
absorb more radiant head and would result in the thawing of near-surface
permafrost under the embankments. In addition to that a scar or
footprint is going to be left in the areas where the roads are built,
ice wedges will be created . Furthermore, animals will be affected by
these roads. For example, migration of birds, crossing of mammals,
etc...
2. Ice Roads :
Ice roads need fresh water, trucks to dispense this water and low
temperatures to keep the road frozen in certain areas.
The freshwater is in limited supply, therefore, using it for building
the roads means less is available for other needs. Also, we will have
lower water levels under ice, so water dwelling organisms will find it
harder to survive. There will be less water for animals to drink. and
since the water level is dropping, toxicity level is going to increase (
as the concentration of toxic materials increases). Ice roads are also
high maintainance, and this maintainance involves alot of physical and
environmental damages. If the ice roads happen to melt, the mix of what
used to be ice and the exhaust of vehicles will run off and contaminate
the soil and water which will not be a very pleasant thing.
For both types of roads , trucks cause damages in the following ways:
1. the warming we talked about that will cause the thawing of the
permafrost near the surface.
2. physical damage, footprints, the museum effect we discussed.
3. polution
_____________________________________________________________________________
PART 4 - Priliminary impact evaluation of seismic exploration: My responsibility within the team was
evaluating the impact of seismic exploration. The following is my impact evaluation, before incorporating
into our team's final impact evaluation that went into the final class website
PART 5 - Final complete impact evaluation:_______________________________________________________________________________________First, a brief overview of what seismic exploration is. I researched the
impacts of all 3 different types of seismic exploration and luckily
enough, team E chose the most environmentally friendly one. Therefore I
will briefly go through the environmental damages caused by the other
strategies (since our job in mission is ultimately to prove that the
methodology we are going to use is the most environmentally friendly)
but I will mainly focus on the one team E proposed using.
A. OVERVIEW OF SEISMIC EXPLORATION:
Seismic exploration involves sending sound waves into the ground then
recording how they are reflected and using this data in interpreting the
geology of the earth's subsurface. It does not explicitly show where oil
is or is not available, but rather it helps construct a model of the
subsurface enabling us to predict where oil can be found. It is very
important for us to realize that even though it does include a certain
degree of uncertainty, seismic exploration is the MOST ACCURATE method
of oil exploration.
There are three different types of seismic exploration:
1. Using explosives
2. By thumping
The main difference between these two methods is that exploration by
thumping uses 30,000 pound trucks that generate the vibrations, whereas
exploration using explosives involves generating the vibrations by
setting off explosives. The particular specifications of these
explosives and how to set them off are highlighted by team E in their
proposal, so I won't go through them again. As I discuss the effects of
oil exploration, I will point out areas in which the precise type of
exploration produces a different effect. For example, seismic waves
produce the same effect regardless of how they are generated. However,
the effects caused by the generation equipment will differ between
thumping and explosives.
3. Using airguns-- this method is only relevant when we are talking
about OFF SHORE EXPLORATION, which is not really the case in most of the
exploration needed in ANWR, thus it is not really taken into
consideration. However, an extremely interesting fact I came across
while researching is that the seismic waves sent into the sea seriously
damage the hearing of fish, according to a joint American-Australian
research team led by Professor Arthur Popper of the University of
Maryland. Although this is not directly relevant to our area of research
it does put forward an important question: What similar serious damages
to land dwelling animals could be caused by seismic exploration that we
do not know of? Obviously the possiblity of damages we are unaware of is
huge and there is a chance of these damages being done.
B. ENVIRONMENTAL IMPACT OF EXPLORATION:
A very useful tool that I relied on when conducting my evaluation is the
Seismic exploration that was conducted along the coastal plain of the
Arctic Refuge during hte winters of 1984 and 1985. It is important to
note that exploration during the winter causes less damage to the soil
and vegetation than does the exploration conducted during the summer.
Team E did not specify when they intend to explore in their proposal, so
it is my advice that all exploration activities take place during the
winter. Despite the fact that it is minimized, damage continues to
occur.
Strong winds usually blow the snow into depressions, leaving the higher
areas with thinner snow cover and making them much more suceptible to
impacts from vehicle tracks. After the 1984-85 seismic exploration 1400
miles of trails that have been made by drill, vibrator and recording
vehicles impacted the tundra in ways that will be outlined below. In
addition to the trails left by the exploration equipment, trails were
also created by D-7 Caterpillar tractors that pulled ski-mounted
trailer-trains between work camps.
In 1999, 15 years after the exploration conducted a significant amount
of the trails persisted. Some of them became troughs that are visible
from the air (all vegetation removed). In other trails, the amount and
type of vegetation present changed. This implies that the entire
food-web dependant on this vegetation is affected and altered. Animals
can be displaced out of their original habitats if their source of food
is no longer available. In other areas, permafrost melted and the trails
remained wetter than they previously were.
Here, a difference between seismic exploration by explosives and seismic
exploration by thumper trucks comes into play. As using explosives uses
less vehicles (no thumper trucks), the physical TRAIL produced is
minimized. However, the explosives still involve digging 12 meter holes
in the ground, which will undoubtedly cause much more severe damage to
the tundra, only this damage is not in the form of a connected extensive
network like that caused by thumper trucks, it is more localized. In
their recommendation, team E proposed the use of snowmobiles by the
teams who are going to drill the holes where explosives will be placed.
This further contributes to minimizing the trail and is a good choice.
As team E explained in the overview section of seismic exploration,
there are different types of maps that can be constructed. In the
1984-85 exploration, 2-D maps were construced. With the advancement of
technology, it became possible to construct 3-D maps as well. Team E did
not specify which type of map they intend to construct, so I will
highlight the difference between both types from the environmental
perspective. First of all, 3-dimentional subsurface image creation
requires a much denser grid than that required for 2-D. The 1984-85
trails were usually four miles apart, whereas the 3-D seismic trails
that are currently impacting areas where they are in use are about half
a mile (or less) apart. This means that the tracked vehicles will
basically blanket the area. 3-D crews are twice the size of 2-D crews,
so more than twice the tracked vehicles are out on the tundra (more
equipment and more bulldozers to transport the camps). Furthermore, the
turns that the heavy equipment need to make are much tighter in 3-D
seismic than they are in 2-D seismic, so the damage made to vegetation
and the tundra in general is greater.
So far, I have been speaking of general damage to the tundra vegetaion
and to animals. The following are more precise effects of winter
exploration (the strategy I'm advising);
Even though the caribou and birds are usually absent from the 1002 Area
during the winter months, there are several species that are adapted to
the harsh conditions and that remain in the area during the winter.
These species are likely to be affected by the seismic exploration
activities. They include primarily muskoxen and polar bears, but there
are also other species including wolverine, arctic fox and arctic
grayling. In addition, the sensitive arctic tundra vegetaion is
affected.
1.Muskoxen:
The population of muskoxen in the 1002 area is approximated to be about
250 muskoxen living all year long. The survival of muskoxen is
influenced by environmental conditions such as the depth of snow, which
is in turn greatly influenced by seismic exploration activities. In
general, the following effects are feared if exploration is to be
conducted in the 1002 area:
a. Displacement of muskoxen from their winter habitat.
b. Due to this displacement, there will be greater energy needs.
Muskoxen need to reduce their activity and movement during the winter in
order to preserve their energy and survive.
c. Decreased body fat in females. This body fat must be maintained
during the winter if they are going to rear a calf.
d. Greater chances of predation.
e. As a consequence of the above, there will be decreased calf
production and less survival of the animals.
2. Polar Bear:
As previously mentioned, seismic exploration involves the movement of
vehicles in grid patterns all across the tundra. Maternal polar bears
with their newborn cubs can be chased out of their winter dens by the
noise and vibrations and all of the human activities that come along
with the exploration activities (particularly the explosives).
Anticipated negative effects include:
a. Human-bear encounters that can be fatal to either party on many
occasions.
b. Increased mortality of cubs due to harsh winter conditions that
they're not prepared for.
3. Vegetation:
Again, as previously mentioned, seismic exploration involves a large
number of vehicles driving across the tundra in a grid or network. The
snow covering the vegetation in the 1002 area is often shallow and
therefore it doesn't provide great protection to the vegetation and soil
underneath. The impact from the seismic grid will depend on the
following:
a. Type of vegetation. Trails in shrub-dominated tundra have the
slowest rate of recovery, whereas trails in sedge-dominated tundra
recover well.
b. Texture and ice content of the soil.
c. The shape of the surface.
d. The depth of the snow, snow depths of at least 25 cm are required to
minimize disturbance.
e. The type of the vehicle. Surprisingly enough, camp move trails
persist much longer and produce a more scarring effect than seismic
trails, due to the greater pressure exerted by camp move trails.
Studies conducted by The U.S. Fish and Wildlife Service (USFWS) after
the 1984-85 exploration showed the following effects:
a. The depth to permafrost was greater on disturbed sites than nearby
controls.
b. Increased thaw depths.
c. Increased trail subsidence.
d. Shifts to wetter conditions.
e. Formation of distinct ruts.
f. Invasion of grasses.
g. Decreases in shrub cover.
h. Long-term disruption of the soil thermal regime.
1. Non-seismic exploration
Due to the fact that magnetic and gravitational exploration do not give off magnetic waves, the only effects produced by this method are caused by the service operations associated with the method.
The effects are:
Due to the airplanes used, there will be noise pollution. In addition to that, the nitrous oxides and carbon monoxide produced will reduce the air quality. Mild, wide-spread, short-term.
Any surface operations necessary will be conducted by using very low impact vehicles, thus producing no significant damage.
2. Seismic Exploration
A very useful tool that we relied on when conducting our evaluation is the Seismic exploration that was conducted along the coastal plain of the Arctic Refuge during the winters of 1984 and 1985.
Also note that 3-Dimensional subsurface image creation requires a much denser grid than that required for 2-D. The 1984-85 trails were usually four miles apart, whereas the 3-D seismic trails that are currently impacting areas where they are in use are about half a mile (or less) apart. This means that the tracked vehicles will basically blanket the area. 3-D crews are twice the size of 2-D crews, so more than twice the tracked vehicles are out on the tundra (more equipment and more bulldozers to transport the camps). Furthermore, the turns that the heavy equipment need to make are much tighter in 3-D seismic than they are in 2-D seismic, so the damage made to vegetation and the tundra in general is greater.
Strong winds usually blow the snow into depressions, leaving the higher areas with thinner snow cover and making them much more susceptible to impacts from vehicle tracks. After the 1984-85 seismic exploration 1400 miles of trails that have been made by drill, vibrator and recording vehicles impacted the tundra. In addition to the trails left by the exploration equipment, trails were also created by D-7 Caterpillar tractors that pulled ski-mounted trailer-trains between work camps. In 1999, 15 years after the exploration conducted a significant amount of the trails persisted. Some of them became troughs that are visible from the air (all vegetation removed). In other trails, the amount and type of vegetation present changed. This implies that the entire food-web dependant on this vegetation is affected and altered. Animals can be displaced out of their original habitats if their source of food is no longer available. In other areas, permafrost melted and the trails remained wetter than they previously were. Severe, localized, long-term.
Even though the caribou and birds are usually absent from the 1002 Area during the winter months, there are several species that are adapted to the harsh conditions and that remain in the area during the winter. These species are likely to be affected by the seismic exploration activities. They include primarily muskoxen and polar bears, but there are also other species including wolverine, arctic fox and arctic grayling. In addition, the sensitive arctic tundra vegetation is affected. Moderate, localized, short-term.
3. Transportation:
a. Rolligons:
Exerts pressure of about 3psi that is relatively less than an ordinary vehicle. They would, however, still leave a small footprint on the ground. Mild, localized, short term.
Atmospheric pollution caused by the use of diesel fuel (see airplanes).
b. Helicopter:
Noise pollution caused by the propellers of the helicopter will affect bird migration, polar bears, and other animals. Mild, localized, short-term.
Hazard of encountering birds in the air which would increase bird mortality and decrease the efficiency of the helicopter. Mild, localized, short-term.
At times air travel will not be possible due to extreme weather conditions which can persist for days. As a result, local storage needs would increase and more pad area would be required. (see environmental impact of surface operations). Mild, localized, short-term.
Degradation of air quality: see airplanes.
c. C-130 Hercules
Landing on snow cover may put pressure on the surface. Moderate, localized, short-term.
May affect air quality. Moderate, wide-spread, short-term.
If an ice strip was used, this would put a strain on water resources since one million liters are required per air strip. Severe, localized, long-term.
The option of using synthetic materials could be a problem if they are not biodegradable or if they are toxic. Severe, localized, long-term.
4. Drilling
Permafrost destroyed when drill bits driven into the ground. The area around the drill hole thaws. Severe, localized, long-term.
The flooding technique of recovering oil from the wells will have two effects:
- It will use up excess H20 Mild, localized, short-term.
- Chemicals will circulate into the ground material. Moderate, localized, long-term.
Benefits of drilling plan:
- Directional drilling and coiled tubing are the best choice: they will provide a minimal impact on the environment. Directional drilling allows for the installation of infrastructure beneath these areas without affecting the delicate ecosystem; animal habitats and sensitive areas can be avoided as a result.
- Coiled tubing reduced the amount of waste produced and results in a smaller footprint. Because the joint connection operations of a convenient drill string are not required, noise levels are reduced as well.
5. Pipeline
Permafrost thaws around pole-support structure. Mild, localized, short-term.
Vegetation does not grow underneath sunlight due to lack of sunlight. Mild, localized, long-term.
Potential fragmentation of habitats. Ex. Caribou might not want to cross underneath pipeline, and although they are not highly active around this area, their migratory route still runs through there. Moderate, wide-spread, long-term.
6.Impact Report: Surface Operations
Of all the aspects of surface operations (pad construction, camp construction, personnel, dining, lodging, maintenance shops, water plants, waste water plants) the largest impact will be caused by the physical existence of the drilling pad. However, all activity has impact, just varying in terms of duration and geographic scope. The impacts of this are listed below, along with a rating of significance. The rating of significance is based on the intensity (magnitude, geographic scope, and frequency/duration) and the probability of occurrence, with the scale being high, moderate, or low. Probability of biological impacts is extremely difficult to predict. Thus, the probability should be evaluated in the context of professional judgment and past occurrences of impacts. In ANWR this is complicated because there has been no prior development to reference to.
ELEVATED PLATFORM
- Support: Steel poles
o Direct impact on permafrost.
Depending on metal used and extent of insulation from high temperature drilling equipment, thawing may occur.
o Attraction for curious, nesting, or hiding animals.
:: Significance:
o Intensity
Magnitude: (LOW) Animals might be scared away from the poles, but since the poles would not block migration, feeding or breeding it is unlikely that it would directly change the size or geographic range of an animal or plant population. The permafrost melting could be minimized with the correct insulation and/or materials.
Geographic Scope: (LOW) The effect would be site specific at a few locations.
Frequency: (HIGH) The poles would be permanently in place
Duration: (LOW) The poles will be removed after the extraction of oil is complete, and therefore will have a finite life of impact
- Operating Surface: Aluminum sheets
o Damage to tundra vegetation by oil leaks
o Damage to tundra vegetation by shading
Could be reduced by having slots or small holes in the pad, allowing some light to get through
:: Significance:
o Intensity
Magnitude: (LOW) This depends on the amount of oil leaked. But since the tundra beneath the platform is already (at least nearly) dead it seems that the effects from oil spills would be a minimal addition to any unavoidable vegetation damage. Animals might come in contact with some leaking oil, but very minimal amounts, and not likely enough to alter an entire population.
Geographic Scope: (LOW) The effect would be site specific at a few locations.
Frequency: (HIGH) The platform would be permanently in place
Duration: (LOW) The pad will be removed after the extraction of oil is complete, and therefore will have a finite life of impact
CONSTRUCTION
- Transportation of the pieces: Helicopter
o Flight will create noise that may be detectable to animals on the ground surface, and occasionally wintering birds
Increased flight elevation will significantly diminish the severity
o No landing pad will be needed as the pieces are to be lowered into place.
Will be increased by holes in pad
:: Significance:
o Intensity
Magnitude: (MODERATE) The impact from the period of construction and removal is understood to be very harsh on both tundra and animals. However, it would not be enough to directly change the size or geographic range of an animal or plant population.
Geographic Scope: (LOW) If the parts are flown in by helicopter, the impact will be site specific at a few locations. If land transport is used then a larger impact might occur.
Frequency: (HIGH) Personnel or equipment would most likely be at the site throughout the construction period
Duration: (LOW) Construction will be very small in terms of the life of the pad, and therefore will have a finite time of impact. The use of the aluminum platform allows for an even smaller construction period, than gravel pads, because gravel pads must wait for the completion of ice roads.
REQUIREMENTS OF PERSONNEL
- Sewage Disposal
o Transport of solids will have noise effects and need for further development of helicopter/plane landing and pumping facilities
This will also be a constant need for gasoline (defeating the purpose of drilling)
o Disposal in or on the tundra will impact the chemical composition of the tundra, and could be especially harmful if water sources are affected.
Possibilities for reuse/recycling should be considered
- Fresh Water
o Fresh water for human use is scarce on the North Slope. Any large needs would deplete fresh water sources for animals, thus possibly beginning a chain of impact through the ecosystem
o Wetland ecosystems would be disturbed by the collection or piping of water from them
Possibilities for desalinization should be considered
- Food
o Transportation of food would cause impacts. See below.
o Storage of food might attract animals.
o Disposal of trash. Might attract animals. Must be flown out eventually (See below).
Note: Possibility in all this for introduction of an invasive species of plant or animal.
- Transportation: People and supplies
o Noise effects from air travel
o Tundra and animals impacted from landing pad/equipment
Ideally a helicopter landing-pad would be on the housing platform adjacent to the drilling platform, to minimize direct tundra impact.
last updated: December 2nd, 2003
