Offshore oil drilling poses risks to the marine environment at every stage. Seismic testing used to locate reserves disorients and harms marine mammals. Drilling and transportation of oil risks catastrophic spills that have long-lasting impacts, as seen with the Deepwater Horizon spill which killed wildlife and disrupted food webs for years. Chronic low-level pollution from drilling and transportation also harms organisms and ecosystems through toxicity, habitat damage, and food web disruption.

1. Marine Impacts from Offshore Oil Drilling
Christian Ricchezza
September 30, 2014
ENSC450 – ProSeminar
Dr. Terrianne Lavin
Off shore oil drilling has become a popular option in the United
States as a way to increase fossil fuel production. However, these
practices are not without adverse effects. This paper explores the
various components of the offshore oil drilling processes and their
impacts on the environment.

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There is growing controversy concerning the practice of offshore oil drilling along the
United States’ coast. The drilling procedure, from beginning to end, has multiple components,
starting with locating subterranean oil reserves, drilling, and transportation of the crude oil.
While offshore drilling has become a popular option in the United States as a way to increase
production of fossil fuels, there is great chance of oil being spilled during both transportation and
drilling. All components involved in the oil drilling process pose serious risks to the plant and
animal life in the ocean.
The process involved for obtaining oil located under the ocean floor is a complicated and
risky procedure. Researchers and scientists must collect topographic data to locate hidden
reserves beneath the seafloor. Seismic tests have become the most commonly used practice for
locating these reserves. Researchers send seismic waves into the ground and the reflected waves
return, revealing buried topography as well as the marks of possible reserves in the area. During
seismic tests, sound waves are created by compressed air guns shooting air into the water. The
compressed air gun has detrimental impacts to the mammals in the vicinity (Moore 2013). A
government relation’s consultant for the Defenders of Wildlife Action Fund stated, "These
seismic waves however disorient whales throughout the vicinity and can lead to mass beaching"
(National Wildlife Federation 2012). Marine mammals are highly sensitive to sounds and the
sound waves created by the seismic tests distort their ability to communicate and travel. Nixon
(2008) noted, to gauge the possible effects from these waves had certain flaws that may have
produced unreliable results. This method is also not a reliable way to locate oil reserves because
seismic tests can only give geologists educated guesses. The associate director of the Bureau of
Economic Geology at the University of Texas even argued, "you never know until you drill”

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(National Wildlife Federation 2012). These tests have the ability to seriously harm the animals in
the ecosystem while being an unreliable method to find oil reserves (Nixon 2008).
The extraction process used in offshore oil drilling can cause an array of threats to the
oceanic environment and pose serious health effects that pose risks to oil platform workers.
Large quantities of extremely toxic fluids are produced during the drilling process. These fluids
include drilling muds, produced water, brine wastes, deck runoff water, and pipeline leaks. Many
fluids, like drilling muds and produced water are disposed of daily by these platforms directly
into the ocean. Tons of drilling fluids and metal cuttings that contain toxic materials such as lead,
chromium, mercury, and benzene leak into the ocean. One drilling platform normally drills
between seventy and one hundred wells, discharging as much as 90,000 metric tons of these
drilling fluids and metal cuttings within the ocean per well (Jervis et al. 2008). Drilling muds are
used for the lubrication of the drill bit and the pipes. They also prevent blowouts by acting as a
sealant within the drilling pipes. There are many different drilling muds used, all of which
include harmful toxic chemicals that can affect marine life. The produced water also poses
extreme risks to the environment. Produced water is the fluid that is trapped underground and
brought up with the extracted oil and gas. This fluid makes up approximately 20% of the waste
produced from offshore oilrigs. These fluids also have an oil content of 30 to 40 parts per
million. Those numbers do not seem too extreme, but as 2 billion gallons of produced water
enters the ocean, 70,000 gallons of oil are released with it (Nixon 2008).
Catastrophic events such as blowouts and major leaks are ever present during offshore oil
drilling operations. One incident in particular that has impacted the oceanic environment in the
Gulf of Mexico, was the Deep Water Horizon incident. On April 20, 2010, there was an
explosion on the British Petroleum- Operated Macondo Prospect oilrig. The explosion killed 11

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people and is considered one of the largest accidental marine oil spills in the history of the
petroleum industry. There was an estimated 170 million gallons of oil that flooded into the Gulf
of Mexico after the explosion. This disaster caused both immediate as well as long term
environmental consequences. In the months following the explosion over 8,000 birds, sea turtles
and marine mammals were found injured or dead. These animals were found in the ocean as well
as on nearby beaches. Birds throughout the vicinity were coated in oil. With their feathers coated
in oil, the birds lost both their ability to regulate body temperature and their buoyancy in the
water. As a result, many birds died from hypothermia and drowning. Sea mammals like
manatees and whales in the area ingested large quantities of crude oil. When these oils are
ingested, ulcers and internal bleeding result. Sea coral was also found dead or dying many miles
from the wreckage site.
The BP spill impacts continue to persist. Even though most of the oil is no longer readily
visible on the surface, it is not gone. The national Wildlife Federation stated that prior to the spill
there was an average of only 100 sea turtles found stranded annually in the area. Since the spill,
there has been roughly 500 sea turtles found stranded every year (National Wildlife Federation
2008). Additionally, the Deep Water Horizon disaster occurred at the peak of the breeding
season for birds, sea turtles, and fish. The eggs and the larvae suffer the most from oil spilled and
can completely diminish or eliminate entire age classes. With the death of large quantities of
juveniles, the delicate food web is impaired. This is a delicate chain and with the creation of an
unbalanced food web, cascading effects will continue into the future. While catastrophic
explosion like the Deep Water Horizon blow out are infrequent, just one disaster can destroy out
an entire ecosystem (National Wildlife Federation 2008).

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Transportation of crude oil poses additional risks to the environment. Most oil rigs are
approximately a mile from the coast requiring the crude oils to be transported by barges and
tankers from the drilling platforms. A 2002 report by the National Research Council found that
marine transportation of crude oils were responsible for one third of total worldwide petroleum
spillage; this is about eight times the amount caused by drilling platforms and pipelines
combined. Mineral Management Service has projected there will be approximately one spill of at
least 1,000 barrels per year over the next 40 years within the Gulf of Mexico alone. They also
stated that every three to four years there will be larger spills and could result in over 10,000
barrels of crude oil being released into the ocean (Jervis et. al, 2008). Therefore, the chances of
oil entering it into the ocean environments become inevitable through the use of offshore
drilling. In addition, when oil makes it into the water, then remains over long periods of time and
inhibits the organisms within the environment and the many people that rely on the coast as their
mode of livelihood. Off shore oil drilling creates additional risks from any complications during
transportation (Jervis et. al, 2008).
Long distance crude oil transportation also presents environmental risks. One example
was the Exxon Valdez disaster. On March 24, 1989, a 987-foot tanker, carrying 53 million
gallons of crude oil, struck the Bligh Reef off the coast of Alaska (Fox News Latino 2014).
Within a few hours there was an estimated 10.8 million gallons of crude oil released into the
water. The crude oil was not contained and as storms and currents interacted with these waters,
oil residue was spread over 13,000 miles of the Prince William Sound’s shoreline (Fox News
Latino 2014). Crude oil poses serious problems to the surrounding waters due to the rate at
which it can spread. Oil spreads on water at a rate of 50 yards per second and the recovery can
often take decades. After 20 years of natural weathering, Prince William Sound appears to have

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been completely recovered by the casual observer. Oil is not readily visible on the surface and
the direct impacts of the oil spill are hidden. Many of the animals higher on the food chain like
dolphins, whales, and predatory fish are only just now starting to recolonize (Nixon 2008). To
this date the fisheries are still experiencing problems. One fisherman noted, "The shrimp are
slowly, slowly coming back. The crab aren't back. The herring aren't back. The salmon are back
in abundance (Fox News Latino 2014).” Out of the many catches for the fisherman, only small
varieties of fish have returned. Even though the Exxon Valdez was carrying crude oil from on
shore. Off shore oil drilling uses the same methods of transportation. With fewer off shore
oilrigs, the number of oil tankers used in the marine environment would decrease, decreasing the
probability of spills.
Coastal wetlands and the marine environments can be greatly impacted by crude oil.
These environments are based on highly organic soils that are extremely compressible making
crude oil difficult to remove. Many life forms, ranging from the smaller organisms like
phytoplankton and arthropods to the higher trophic levels like fish and whales rely on these
environments for their survival. Oil exposure kills existing plant life in these communities as
well as prevents future plants from growing. Plant roots are essential in binding the soil together.
Without plants the soils will erode. Over time, continuous erosion hinders the rate at which plant
communities can grow back (Godfrey 2010). As the plants are impacted by oil, so are the
wildlife that use them for cover and food. The National Wildlife Federation stated, "Ninety
percent of all marine species depend on coastal estuaries at some point in their lives." Due to the
low energy rate and anoxic environments, oil stays in these environments over long periods of
time. The organisms within these environments experience long term reproductive and health
defects from chronic exposure to oil (National Wildlife Federation 2014).

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Organisms lower on the food chain like terrestrial arthropods and phytoplankton play
important roles in the mediating process and support higher trophic levels in coastal wetlands.
Marine arthropods affect the decomposition of dead plant material as well as affect plant
biomass. These organisms are also a food source to animals higher on the food chain. Arthropods
act as a trophic link between terrestrial and marine vertebrates as most predatory species use
them as a food source (Pennings et al. 2014). With a reduction of arthropods in the environment,
the health of both the predatory animals and coastal wetland environments are at risk. Other
lower trophic species like phytoplankton have adverse effects from oil exposure. While the
growth of some phytoplankton are stimulated from oil exposure, other, species experience
inhibited growth. The assembly of phytoplankton within the surrounding ecosystem are
vulnerable to changes from oil exposure. Even delicate changes to phytoplankton communities
can cause serious complications in the food web (Pennings et al. 2014). An unbalanced food web
decreases the biodiversity of the community and prevents it from flourishing.
In the event of an oil spill, larger animals within the biological community are also
susceptible to crude oil impacts. Marine animals including fish, birds, and mammals are
susceptible to contact, smothering, and toxicity. These effects may be from physical and
chemical properties of the spilled oil. Fish may come into contact with toxic and volatile water
columns, which are vertical expanses of water between the surface and the sea floor. This contact
would contaminate their gills as well as poison eggs and larvae. Sea birds spend the majority of
time on the sea surface and already have low reproductive rates which makes them more
vulnerable to oil spill contamination (Environmental Protection Agency 1999). Direct exposure
of crude oil to mammals may result in temporary eye problems. Species that groom themselves
like birds and some mammals may also be susceptible to liver or kidney damage. These animals

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ingest the toxic oil on their feathers, skin, or fur in attempts to remove the oil. If these mammals
breathe in any hydrocarbon vapors, nerve damage and behavioral abnormalities may result
(Horrowitz 2014). When crude oil enters the marine environment, negative impacts towards the
marine organisms are inevitable.
Chronic exposure to crude oil creates even greater damage to marine animals.
Extended exposure to crude oil results in fish having more genetic abnormalities and an increase
in the growth of cancer cases for sensitive species. Entire generations of species could be
eradicated due to oil spills. Birds’ are impacted by chronic exposure to crude oil in different
ways. With continued contact, the birds’ feathers lose their waterproof capabilities (Horrowitz
2014). When their feathers are unable to repel water, their ability to remain buoyant is impeded,
increasing the risk of drowning. Birds ingesting crude oil suffer long term reproductive
consequences. Ingestion frequently results from feeding on oil covered prey at the surface or
from cleaning their feathers (Environmental Protection Agency 1999). Chronic effects of crude
oil exposure to mammals vary depending on the importance of their blubber and fur properties. If
these mammals fur coats are covered in crude oil they lose their ability to keep warm and
eventually suffer hypothermia and death. Procedures to mitigate oil covered marine animals have
not been extensively developed and may cause further harm to the animals. Some mammals are
more susceptible to secondary fungal and bacterial infections such as manatees in the Gulf of
Mexico (Horrowitz 2014). These bacterial infections are produced during the cleaning efforts of
oil spills. Another difficulty in the mitigation process is cleaning species like fish and turtle, that
predominantly live deeper in the ocean. When an organism comes into contact with crude oil in
the oceanic environment, they are impacted on both the short term interval and long term time
scales.

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Coral communities experience short term as well as long term effects from the presence
of oil in the oceanic environment. Deep water coral communities are more susceptible to
submerged oil plumes that contain toxic hydrocarbons. Marine oil plumes tend to favor areas
where there are depressions and low current velocities. Corals favor areas of the sea floor with
sufficient currents to facilitate food delivery as well as gas exchange. When the hydrocarbon rich
oil dissolves onto the surrounding coral communities, they cannot withstand the additional
sediment deposition and accumulation and they die (Shigenaka 2001). In 2010, after the
Macondo oil well explosion, many coral communities were discovered damaged in the vicinity.
The characteristics of these coral communities however, differed from healthy coral’s that have
been seen in the Gulf. Large portions of the sea coral communities were covered in brown
flocculants that contained clumps of fluffy toxic particles. There were also additional signs of
stress, including excess mucous production and tissue loss. The brown flocculants contained
weathered oil as well as hydrocarbons that were consistent with the Macondo Oil explosion.
Coupling these data with the location, depth, and timing of the explosion indicated the corals
were damaged by oil spilled from the Macondo explosion (Fisher et al. 2014). Oil released into
the ocean has drastic impacts on local coral communities caught in its pathway.
Over time the effects from oil spills persist and continue to impact coral communities. A
further study of the coral communities within the Macondo well vicinity showed there was a
distinct difference between the corals soaked in the brown flocculent sediment than those that
were clean. The corals covered in the flocculent material decreased in size. Those corals with
less than 20% coverage were likely to make a full recovery (Fisher et al. 2014). Their data
showed that the accumulation rate of the hydrocarbons is higher than the dispersal rate. Over the
long term, damage will become progressively worse. By March of 2012, coral communities

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exhibited healthy colonized branches mixed with dead branches colonized by hydroids. Coral
communities normally have multiple organisms living within them. However, the presence of
excess hydroids in the damage coral is evidence of coral stress. There were 69 coral communities
imaged and of the 69 clones, 47 showed characteristics of hydroid colonization on at least 5% of
their surface area. Other coral colonies showed no living tissue at all and many impacted
colonies have not yet been discovered (Fisher et al. 2014). The presence of oil near coral
communities is not an acute problem, but a chronic problem that persists over time, decaying the
living tissue of these fascinating organisms.
The many components of the offshore drilling process produce serious risks to both the
environment and the organisms that live there. Offshore drilling may seem beneficial to our
economy, but the ecological damage that it presents may be far worse over time. Seismic
location of reserves disorients thousands of whales and dolphins. In addition, the necessary
transportation of crude oil and drilling procedures for its extraction are not full proof. Both the
Deep Water Horizon explosion and the Exxon Valdez spill demonstrate the catastrophic
accidents that may result from offshore oil drilling and transportation. Both, adversely affected
the water, the plant, and animal life in the area. Over 20 years later, the Alaskan coastline has yet
to fully recover from the Exxon Valdez spill. Continuing to pursue offshore drilling increases
exposure to oil spills. The oceanic environments will continue to degrade because the overall
process of oil drilling is flawed. The entire ocean comprises 71 percent of our planet and if we
continue to pollute it with oil spills, we may reach a point of no recovery.

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