DEEPWATER HORIZON OIL SPILL

DEEPWATER HORIZON OIL SPILL

• Also referred to as the BP oil spill, the BP oil disaster, the Gulf of Mexico oil spill, and the Macondo blowout

• Largest marine oil spill in history• Caused on April 20, 2010• An explosion on the Deepwater Horizon oil rig

and its subsequent sinking on April 22

Deepwater Horizon• An ultra-deepwater,  offshore drilling rig owned by Transocean. • Built in 2001 in South Korea by Hyundai Heavy Industries.• The oil well over which it was positioned was located on the seabed 4,993 feet (1,522 metres) below the surface and extended approximately 18,000 feet (5,486 metres) into the rock.

Location of deepwater horizonlocated in the Gulf of Mexico, approximately 41 miles (66 km) off the

coast of Louisiana

STAKEHOLDERS

BP, British Petroleum, is a British multinational oil and gas company headquartered in London, England.

SHARE: 65 percentAnadarko is an American petroleum and

natural gas exploration company in Texas. SHARE: 25 percent

Mitsui Oil Exploration Co.(MOEX Offshore), SHARE: 10 percent

HISTORY OF THE OPERATION

• On March 19, 2008, BP obtained a 10-year lease in Central Gulf of Mexico, conducted by the Minerals Management Service (MMS).

• Initial drilling of the Macondo well began on October 6, 2009.

• The Deepwater Horizon was selected in January 2010 for drilling the Macondo well.

• The planned well was to be drilled to 18,360 feet (5,600 m) below sea level

INCIDENT

• On the night of April 20 a surge of natural gas blasted through a concrete core.

• The natural gas traveled up the Deepwater rig’s riser to the platform, where it ignited, killing 11 workers and injuring 17.

• The rig sank on the morning of April 22.• Ruptured the riser.• Without any opposing force, oil began to

discharge into the gulf.

CAUSES

• The accident at Deep water horizon is not an accident not only due to time-action gapping, but also some sequential events related to maintenance.

• Explosion is the main reason behind this oil spill.

• At first it was `blow out preventer’ (which was designed to shut down the well) failed to shut down the well.

• Secondly. There was a technical fault in design of the gas venting system which allows a cloud of explosive gas to envelop the rig

• At last the additional valves deep

inside the well failed to prevent oil and gas from flowing up the steel pipe

• Dodgy cement• The cement at the bottom of the

borehole did not create a seal, and oil and gas began to leak through it into the pipe leading to the surface

• Quality of cement:• The cement contained a nitrogen

additive to make it lighter so that it would flow more easily.

• This also may have decreased its sealing effectiveness

• Pressure test misinterpreted:• The crew carried out various pressure tests to

determine whether the well was sealed or not. The results of these tests were misinterpreted

• No gas alarm:• The rig had an onboard gas detection system

that should have sounded the alarm and triggered the closure of ventilation fans to prevent the gas reaching potential causes of ignition

IMPACTS FROM THE DEEPWATER HORIZON OIL SPILL ON GULF OF MEXICO FISHERIES

The oil spill affected fisheries on three different levels: 1. The Individual Level, or how oil spills may

impact a single living thing (like a fish).2. The Population Level, or how oil spills may impact

a group of living things of the same species. 3. Community-Wide Impacts or how oil spills cause deformities in the developing larvae of blue fin tuna and other communities .

• IMPACTS TO MARINE SPECIESStriped dolphins swim among emulsified oil

patches on April 29, 2010 in the Gulf of Mexico, a few days after the Deepwater Horizon oil spill.

Sea turtle nests also have gone down in these years

That rose to 125 in the seven months after the spill in 2010 and 335 in 2011 .Reported Reuters in 2015.

“From 2002 to 2009, the Gulf averaged 63 dolphin deaths a year.

DOLPHINS AND SEA TURTLES : Stranding of both Dolphins and sea turtles increased significantly in the years following the spill.

SEA BIRDS Seabirds were

harmed by crude surface oil even a small bit of oil on

their feathers impeded their

ability to fly, swim and find food by

diving.

INVERTEBRATSInvertebrates

in the Gulf were hard hit

by the DHS both in coastal

areas and in the deep.

DEEP WATER CORALS

Found as deep as 4,000 feet

below the surface

Corals near the blow out

showed signs of tissue damage

ECOSYSTEM EFFECTS

The Gulf is composed of inter-related ecosystems that stretch from estuaries and coastal wetlands to the pelagic zone (open ocean).

THE HUMAN HEALTH CONSEQUENCES

• The spill exposed people to oil fumes, Volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals

• ACUTE TOXIC EFFECTS, Neurological, ocular (eye), respiratory,

nausea, Headaches ,Eye, nose, and throat irritation.

• By 21 June 2010, 143 oil spill exposure cases had been reported

108 of those cases involved workers in the clean-up efforts,

35 were reported by gulf residents.

Remedial measures

• The fundamental strategies that were taken to clean the oil spill were

1. Containment booms2. Dispersant 3. Combustion4. Collection

1.Containment booms

• Oil when spilled, tends to float to the surface and spread out, forming a thin slick just a few millimeters thick.

• Cleanup workers surrounded the slick with floating booms a physical barrier to keep it from spreading

CONT….

• Sorbent Booms extend 18–48 inches above and below the water surface .

• A total of 13,300,000 feet of booms were deployed.

• Sorbents either absorb oil like a sponge or adsorb oil, which means that oil sticks to its surface.

CONT….

• They come in three main types: 1. Natural organic materials like peat moss and

hay2. Natural inorganic materials like clay, volcanic

ash and sand3. Synthetic sorbents made of materials similar

to plastic like polyurethane, polypropylene, and polyethylene.

2.USE OF DISPERSANT

• Dispersants are chemicals that break down the oil into smaller particles

• Evaporation and bacteria can then degrade these tiny droplets

• waves can wash them away from the spill site.• Oil was treated with over 1.4 million gallons of

various chemical dispersants

CONT..

• Dispersant were spread over the open ocean from an airplane or helicopter.

• Usage of dispersants was described as "the most effective and fast moving tool for minimizing impact”

3.COMBUSTION

• About 5% of leaked oil was burned at the surface and 3% was skimmed.

• Controlled in-situ fires remediated approximately 265,000 barrels.

• The fires released small amounts of toxins, including cancer-causing dioxins

4.COLLECTION

• Oil was collected from water by using skimmers.

• In total 2,063 various skimmers were used• In mid-June 2010, BP ordered 32 machines

that separate oil and water• Each machine was capable of extracting up to

2,000 barrels per day.• By 28 June, had removed 890,000 barrels