OIL SPILLS

Presented by:Nayyab Nadeem

Hamayal Wajid lodhiShaima saqibSara Hassan

Sajal Shahbaz

What are Oil Spills?• An oil spill is the release of a liquid petroleum hydrocarbon into

the environment, especially marine areas, due to human activity, and is a form of pollution.

• The term is usually applied to marine oil spills, where oil is released into the ocean or coastal waters, but spills may also occur on land.

• Oil spills may be due to releases of crude oil from tankers, offshore platforms, drilling rigs and wells, as well as spills of refined petroleum products and their by-products, heavier fuels used by large ships such as bunker fuel, or the spill of any oily refuse or waste oil.

• Cleanup and recovery from an oil spill is difficult and depends upon many factors, including the type of oil spilled, the temperature of the water (affecting evaporation and biodegradation), and the types of shorelines and beaches involved.

• Spills may take weeks, months or even years to clean up.

• Crude oil and refined fuel spills from tanker ship accidents have damaged natural ecosystems in Alaska and many other places.

• The quantity of oil spilled during accidents has ranged from a few hundred tons to several hundred thousand tons .

• Smaller spills have already proven to have a great impact on ecosystems, such as the Exxon Valdez oil spill because of the remoteness of the site or the difficulty of an emergency environmental response.

• Oil spills at sea are generally much more damaging than those on land, since they can spread for hundreds of nautical miles in a thin oil slick which can cover beaches with a thin coating of oil.

GREATEST IN HISTORYM/T Haven Tanker, 1991Location: Genoa, ItalyGallons: 42 million

How It Happened: An apparently shoddily maintained tanker exploded and later sunk off the coast of Italy. The accident killed six people.

Immediately after the incident, an effort by the Italians to tow the Haven to shore failed, and the 820-foot-long (250 meter) vessel sunk off the coast of Genoa. Today it is believed to be the largest shipwreck in the world and is a popular tourist destination for divers.

The Cleanup: Immediately after the incident Italian authorities scrambled to fight the fire and control the spread of the spillage using six miles of inflatable barriers that were submerged below the water surface around the vessel. The rest of the surface oil was sucked up using vacuums.

Fergana Valley, 1992Location: Uzbekistan Gallons: 87.7 million

How It Happened: Nearly 88 million gallons of oil spilled from an oil well in Fergana Valley, one of Uzbekistans’s most active energy- and oil-refining areas. While the spill didn’t get much press at the time, it is the largest inland spill ever reported.

The Cleanup: The ground absorbed this spill, leaving nothing for cleaning crews to tackle.

Nowruz Oil Field, 1983Location: Persian Gulf Gallons: 80 million

How It Happened:Smack in the middle of the Iran-Iraq War, an oil tanker crashed into the Nowruz Field Platform in the Persian Gulf and knocked it askew, damaging the well underneath. The oil well then leaked about 1500 barrels a day, but because it was in the center of a war zone, seven months went by before it was fixed.

The Cleanup: Norpol, a Norwegian company, used booms and skimmers to stem the spread of oil.

ABT Summer, 1991 Location: Off the coast of Angola

Gallons: 80 million

How It Happened: While en route to Rotterdam, the fully loaded tanker ABT Summer experienced an explosion onboard and caught fire while it was 900 miles off the coast of Angola, leaking its payload into the ocean.

Surrounded by a growing oil slick that spanned 80 square miles, the tanker burned for three days before sinking.

The Cleanup: While no one can say how much of the oil sank or burned off, most of the oil is thought to have been broken up by high seas at little environmental cost, thanks to the incident’s offshore location.

Odyssey Oil Spill, 1988 Location: 700 nautical miles off the coast of Nova Scotia, Canada

Gallons: 43 million

How It Happened: In November 1988 the Liberian tanker Odyssey, virtually full to the brim with North Sea crude oil, broke in two and sunk in the North Atlantic 700 miles off the coast of Nova Scotia. It also caught fire as it sunk.

The Cleanup: Because the incident took place so far from the coastline, the oil was expected to dissipate naturally, ergo no clean up at all.

Effects of Oil Spills

Presented by: Hamayal Wajid Lodhi

Marine Ecosystem including animal

and plant life

Local industries Human health

Effect on local industries• Local industries effected include tourism as fishing, swimming or

sailing is made impossible in the event of an oil spill. • Industries that rely on fresh sea water also are effected and

cannot resume their activities till the water has been cleaned up • Fishing industry suffers majorly, not only because of the large

amount of marine life lost, but as the catch obtained would be covered in oil and is hence inedible as they’re poisonous.

• Furthermore, devices used to catch fish cannot be used for fear of damaging them in area that have had an oil spill, which means that boats can also not be used for the same reason.

• The impacts are however short term and are remedied once cleaning has been done, as fish reproduce in large numbers.

Effect on Human Health• Inhalation of vapor, touching oil

slicks and consuming contaminated sea food

• Exposure may cause neurological, acute toxic effects, ocular (eye) and also problems of respiratory system.

• People living in effected areas showed nausea, throat infections, nose and eye irritations etc along with migraines and headaches.

• Ingestion of oil produces in sea food is dangerous as oil products having polycyclic aromatic hydrocarbons (PAH). These are human carcinogens.

Effect on Marine EcosystemFactors on which it depends

Spread of oil slick

Movement (waves)and weather (cold , low energy, little water

movement)

Area effected i.e. estuaries/ foreshore

Proximity to bird breeding colony

Timing i.e. during bird migration/ seasonal

breeding

Vegetation • Oil spills also have impacts on vegetation, • Oil reaching the root areas of plants may be

harmful• However, a thick coating of oil on the leaves

does almost no damage if it occurs outside the growing season.

• Loss of sea grasses and other vegetation is harmful as these are food supplies for organisms.

• Living coral is also vulnerable to oil slicks. If the living coral dies, then the reef of coral can be destroyed by wave erosion. This means many fish and animals lose their homes.

Mangroves• Are salt tolerant tress and shrubs and provide

habitat for sea birds, crabs, oysters, breeding ground for birds, Their complex root system stabilizes and sediment, preventing soil erosion

• They are vulnerable to oil spills as they obtain oxygen through lenticels on aerial roots, which may become clogged and stop oxygen supply

• Toxic components in oil may also upset plants mechanism of maintaining salt balance

• There may be long term loss of habitat

Categories of Marine Life Effected

Pinnipeds Sirenians

Cetaceans Marine Mammals

Sea Birds Sea Turtles

Fish

Effect on Marine Life• Oil, or hydrocarbons, can affect plants and animals in

different ways.• One of the most visually alarming physical effects on marine

birds and mammals is through smothering, where oil coats the outside of their bodies, covering feathers and fur.

• A less obvious impact is a toxic response to the oil.• Toxic compounds from the spilt oil can be ingested by

animals directly, in their prey, as they breath or as they clean their fur or feathers, causing short and long term negative impacts.

• These impacts can be difficult to quantify.

Sea Birds• Spend more time on or near effected

shores• Oil causes feathers to collapse and matt.

This may:1. and change the insulation properties of

feathers and down. 2. This can severely hamper the ability of

birds to fly.3. A breakdown in the water proofing and

thermal insulation provided by the feathers, causing hypothermia.

4. seabirds lose buoyancy, sink and drown because of increased weight or lack of air trapped in the feathers.

5. Body weight decreases quickly as the metabolism attempts to counteract low body temperature.

Internal effects can include:• reduced reproduction ability,• reduction in the number of eggs laid,• decreased fertility of eggs,• decreased shell thickness and• disruption of the normal breeding and

incubating behaviors • If oil spill occurs during breeding season,

effects are more drastic and this holds true for all marine life

Marine Mammals• These include sea otters, sea lions,

seals, walruses, sea cows (dugongs), dolphins, porpoises and whales

• Marine mammals are vulnerable to oil spills because of their amphibious habits and their dependence on air

• They show migratory behaviors hence they show lesser impact due to oil spills as compared to other animals

• The rough skin surface, body hair and grooming habits of some species increase the possibility of oil contact, ingestion and associated toxicological effects.

• The Exxon Valdez oil spill killed thousands of sea otters, hundreds of harbor seals, roughly two dozen killer whales and a dozen or more river otters. Even more troubling in some ways, in the years after the Exxon Valdez oil spill scientists noted higher death rates among sea otters and some other species affected by the oil spill, and stunted growth or other damage among other species.

Cetaceans• Less effected due to reclusive and

migratory behavior• They also have smooth surfaces

with little hair so contact with oil by whales may cause only minor oil adherence.

• Baleen whales, which skim the surface are more likely to ingest oil than "gulp feeders" or toothed whales.

• Inhalation during surfacing could damage mucous membranes, damage airways or even cause death.

Beluga whales

Pinnipeds

• Spend much of their time on or near the surface of the water, to breathe or haul our of sea

• Fur seals are more vulnerable as oil adheres to fur, leading to reduced swimming ability and lack of mobility out of the water.

• seal pups , mostly furry, are severely effected as oil makes their flippers stick to their bodies, leading to drowning or increased predation.

• Their mothers cannot identify them hence as they cannot distingush them from their smell. They may not feed it or it might even reject attempts by the pup to suckle. This leads to starvation and abandonment.

• Oil sinks and can have damaging effects on fragile underwater ecosystems, killing/ contaminating many fish and smaller organisms that are essential links in the global food chain.

• Unbalanced Food Web - When oil spills happen around breeding season, like the gulf oil disaster, egg and larval populations are diminished or wiped out, effecting food web.

• Decreased Fish and Wildlife Populations -Herring population collapsed 4 years after the 1989 Exxon Valdez oil disaster that the herring population collapsed. Twenty years later, it is still has not recovered.

• Decline in Recreation - Gulf states that relied on fishing and recreation have been deprived of both from May to August, and state park closures dealt a serious blow to tourism.

Long Term Impacts

CLEAN UP OF OIL SPILLS

On The Beach

• Bioremediation The application of certain fertilizers to beaches stimulates the growth of "oil-eating" microbes. This fertilizing process is known as Bioremediation.

• Hot Water & High Pressure By using hot water at high pressure, cleanup crews blast oil off beaches into the water where it can be skimmed off.

• Manual Treatment Manual treatment incorporates the use of shovels, rakes, absorbent materials and human hands.

• Mechanical Treatment Tractors loaders, and other machines

On The Water

• Boom comes in many sizes, shapes, and types and is used primarily to deflect and/or collect oil

• Burning Fresh oil contains gases which are very volatile. By igniting these gases whole oil slicks can be reduced to tarry residue.

• Dispersants are used to do just that, disperse. They are chemicals that break-up oil into smaller and smaller concentrations. Potentially into individual molecules

• Skimming is a mechanical system for removing oil from the surface. This process was created based on the reality that oil is lighter than water.

BOOMS are First Used toContain the Oil Spill

Photo by EPA

Booms in Action

Booms Containment booms control the spread of oil

to reduce the possibility of polluting shorelines and other resources,

• concentrate oil in thicker surface layers, • divert and channel oil.• Booms are anchored to tied to buoys• Need to be monitored for changes for tides

and shifts in waves.• Wood pipes, plastics, tyres ,etc. inflated

material.

STRUCTURE

• An above-water "freeboard" to contain the oil and to help prevent waves from splashing oil over the top of the boom

• A flotation device• A below-water "skirt" to contain the oil and help reduce

the amount of oil lost under the boom• A "longitudinal support," usually a chain or cable running

along the bottom of the skirt, that strengthens the boom against wind and wave action; the support may also serve as a weight or ballast to add stability and help keep the boom upright

In situ BURNING

• the process of burning oil slicks at sea, at or close to the site of a spill.

• removes large amounts of oil from the sea surface.• there are a number of problems which limit the

viability of this response technique. • the ignition of the oil; maintaining combustion of the

slick; the generation of large quantities of smoke; the formation and possible sinking of extremely viscous and dense residues; and safety concerns.

Ignition

• Helitorch is a flame-thrower which is suspended beneath a helicopter and is generally accepted as being one of the safest methods of ignition in trained hands.

• Fire proof containment boom and an igniter will most probably be required for a burn to be undertaken.

• Issues such as the distance of the oil from the damaged vessel or from a populated area; the potential toxicity of the resultant smoke; the nature of the oil.

Residue• The viscous residue that can be left following in-situ

burning resembles the consistency of toffee, • it is difficult to recover both at sea and from the shoreline.• Sunken residue has the potential to smother or poison

bottom dwelling (benthic) species. • In the response to the spill from the HONAM JADE (South

Korea, 1983) crude oil was deliberately ignited. As a result, a dense residue formed which sank and seriously contaminated shell fish beds. When oil does sink to the sea bed and cause problems, the scope for recovering it is limited.

SKIMMERS• A skimmer is a device for recovering spilled oil from the

water's surface. • Skimmers may be self-propelled, used from shore, or

operated from vessels. • The efficiency of skimmers depends upon conditions at sea. Oleophilic skimmers use belts, disks, or continuous mop chains

of Oleophilic materials to blot the oil from the water surface. The oil is then squeezed out or scraped off into a recovery tank. Can be used effectively on spills of any thickness.

Suction skimmers operate similarly to a household vacuum cleaner. Oil is sucked up through wide floating heads and pumped into storage tanks.

SORBENTS

• Sorbents are insoluble materials or mixtures of materials used to recover liquids through the mechanism of absorption, or adsorption, or both.

• To be useful in combating oil spills, sorbents need to be both Oleophilic (oil-attracting) and hydrophobic (water-repellent).

• They are as the sole cleanup method in small spills.• sorbents are most often used to remove final traces of

oil, or in areas that cannot be reached by skimmers. • Sorbent used to recover oil must be disposed of in

accordance with approved local laws . Any oil that is removed from sorbent materials must also be properly disposed of or recycled.

Natural organicsorbents

• include peat moss, straw, hay, sawdust ,feathers .The adsorb between 3 and 15 times their weight in oil

Natural inorganic sorbents

• consist of clay, perlite, glass wool, sand, or volcanic ash. They adsorb from 4 to 20 times their weight in oil.

Synthetic sorbents

• man-made plastics, rubber ,polyethylene, polypropylene that adsorb liquids and swell. They absorb up 70 times their own weight in oil.

Physical methods

• Wiping with sorbents

• Raking• Shoveling

Scare tactics

• Cans• Dummies• Helium balloons

GELLING AGENTS• Gelling agents, aka solidifiers, are chemicals that react with oil

to form rubber-like solids.• With small spills, they are applied by hand and left to mix on

their own.• For treating larger spills, the chemicals are applied to the oil,

then mixed in by the force of high-pressure water streams. The gelled oil is removed from the water using nets, suction equipment, or skimmers, and is sometimes reused after being mixed with fuel oil.

• Gelling agents can be used in calm to moderately rough seas.• Drawback is that Large quantities of the material must often be

applied, as much as 3X the volume of the spill. For oil spills of millions of gallons it is impractical.

Dispersants• Dispersants are chemical solvents or

surfactants.

• They don't eliminate oil, they make it less obvious by breaking it into small pieces which spread throughout the ocean.

• The dispersant Corexit is being used by BP and has been proven to be toxic to microorganisms and fish eggs.

BIOREMEDIATION AND BIODEGRADATION

Presented by : Shaima Saqib

• Bioremediation is a waste management technique that involves the use of organisms to remove or neutralize pollutants from a contaminated site.

• Technologies can be generally classified as in situ or ex situ.

• In situ bioremediation involves treating the contaminated material at the site, while ex situ involves the removal of the contaminated material to be treated elsewhere.

• Some examples of bioremediation related technologies are phytoremediation, bioventing, bioleaching, landfarming, bioreactor, composting, bioaugmentation.

• Bioremediation may occur on its own (natural attenuation or intrinsic bioremediation) or may only effectively occur through the addition of fertilizers, oxygen, etc., that help encourage the growth of the pollution-eating microbes within the medium.

• Recent advancements have also proven successful via the addition of matched microbe strains to the medium to enhance the resident microbe population's ability to break down contaminants.

The Biological and Chemical Processes of Bioremediation

• Many microorganisms possess the enzymatic capability to degrade petroleum hydrocarbons.

• Some microorganisms degrade alkanes, others aromatics, and others both paraffinic and aromatic hydrocarbons

• More complex structures are more resistant to biodegradation, meaning that fewer microorganisms can degrade those structures and the rates of biodegradation are lower than biodegradation rates of the simpler hydrocarbon structures found in petroleum. The greater the complexity of the hydrocarbon structure, i.e., the higher the number of methyl branched substituents or condensed aromatic rings, the slower the rates of degradation

Degrading Species

•The biodegradation of petroleum in the marine environment is carried out largely by diverse bacterial populations, including various Pseudomonas species. • The hydrocarbon-biodegrading populations are widely

distributed in the world’s oceans; surveys of marine bacteria indicate that hydrocarbon-degrading microorganisms are ubiquitously distributed in the marine environment.

• Generally, in pristine environments, the hydrocarbon-degrading bacteria comprise < 1% of the total bacterial population.

• These bacteria presumably utilize hydrocarbons that are naturally produced by plants, algae, and other living organisms. They also utilize other substrates, such as carbohydrates and proteins.

• When an environment is contaminated with petroleum, the proportion of hydrocarbon-degrading microorganisms increases rapidly. In particular, in marine environments contaminated with hydrocarbons, there is an increase in the proportion of bacterial populations with plasmids containing genes for hydrocarbon utilization.

Need for Bioremediation

• It is particularly important to address oil polluted waters as soon as

possible as the contamination can have the potential to damage fishery resources and affect the health of those animals and humans that consume contaminated fish . Besides the varying rates of biodegradation, researchers have consistently documented a lag time after oil is spilled before indigenous microbes begin to break down the oil molecules

• This lag time is related to the initial toxicity of the volatile fractions of the oil, which evaporate in the first few days of a spill. Microbial populations must begin to use oil and expand their population before measurable degradation takes place, a period usually lasting several days. This fact becomes very important when considering the appropriateness of bioremediation as a quick or first response technique

Seeding with Microbial Cultures

• One approach often considered for the bioremediation of petroleum pollutants after an oil spill is the addition of microorganisms (seeding) that are able to degrade hydrocarbons. Most microorganisms considered for seeding are obtained by enrichment cultures from previously contaminated sites.

• However, because hydrocarbon-degrading bacteria and fungi are widely distributed in marine, freshwater and soil habitats, adding seed cultures has proven less promising for treating oil spills than adding fertilizers and ensuring adequate aeration

Environmental Modification

• Hydrocarbon biodegradation in marine environments is often limited by abiotic environmental factors such as molecular oxygen, phosphate and nitrogen (ammonium, nitrate and organic nitrogen) concentrations.

• Rates of petroleum biodegradation are negligible in anaerobic sediments because molecular oxygen is required by most microorganisms for the initial step in hydrocarbon metabolism. Oxygen, however, is not limiting in well aerated (high energy) marine environments .

• Usually, marine waters have very low concentrations of nitrogen, phosphorus and various mineral nutrients that are needed for the incorporation into cellular biomass, and the availability of these within the area of hydrocarbon degradation is critical.

Prevention & ENVIRONMENTAL SENSITIVITY INDEX (ESI) MAPPING

Presented by:Sajjal Shahbaz.

Prevention• Secondary containment : methods to prevent releases of oil or hydrocarbons into

environment.• Oil Spill Prevention Containment and Countermeasures

(SPCC) program by the United States Environmental Protection Agency.

• Double-hulling : build double hulls into vessels, which reduces the risk and

severity of a spill in case of a collision or grounding. Existing single-hull vessels can also be rebuilt to have a double hull.

• Thick-hulled railroad transport tanks

ENVIRONMENTAL SENSITIVITY INDEX (ESI) MAPPING

• The Environmental Sensitivity Index (ESI), developed by RPI’s senior scientists in 1976, has become an integral component of oil-spill contingency planning , response and coastal resource management in the USA and other countries worldwide.

THE ESI DIGITAL DATABASES ARE SUITABLE FOR USE ACROSS WIDE RANGE OF NATURAL RESOURCE MANAGEMENT APPLICATIONS

PURPOSE OF ESI MAPS:

• Environmental Sensitivity Index (ESI) maps are used to identify sensitive shoreline resources prior to an oil spill event in order to set priorities for protection and plan cleanup strategies. By planning spill response ahead of time, the impact on the environment can be minimized or prevented.

Environmental sensitivity index maps are basically made up of information within the

following three categories:

Shoreline type

Biological resources

Human-use resources

Shoreline Classification:

• Ranked according to a scale relating to sensitivity, natural persistence of oil, and ease of cleanup. The sensitivity ranking is controlled by the following factors:

1) Relative exposure to wave and tidal energy;2) Shoreline slope;3) Substrate type (grain size, mobility, penetration,

and traffic ability); and4) Biological productivity and sensitivity.

Biological Resources• Including oil-sensitive animals and rare plants; and habitats, which are used

by oil-sensitive species or are themselves sensitive to oil spills, such as submersed aquatic vegetation and coral reefs.

• Biological resource information collected and used in ESI maps can also be used for coastal resource management. The type of data collected for the biological resources are:

1) Large numbers of individuals are concentrated in a relatively small area;2) Marine or aquatic species present during special life stages or activities,

such as nesting, birthing, resting, or molting;3) Early life stages or important reproductive activities occur in somewhat

restricted areas;4) Restricted areas important to specific life stages or migration patterns;5) Specific areas are known to be vital sources for seed or propagation;6) The species are threatened, endangered, or rare; or7) A significant percentage of threatened/endangered species are likely to

exist.

Human-Use Resources:

• Specific areas that have added sensitivity and value because of their use, such as:

1) High-use recreational and shoreline access locations (i.e. beaches, parks, boat ramps, etc.);

2) Management areas (i.e. refuges, preserves, sanctuaries, etc.);

3) Resource extraction locations (i.e. water intakes, aquaculture/lease sites, etc.); and

4) Archaeological, Historical, and Cultural resource sites.

Reference sites

• http://www.researchplanning.com/projects/noaa-environmental-sensitivity-index-esi-mapping/

• http://en.wikipedia.org/wiki/Oil_spill