Ixtoc 1
On 3 June 1979, in the Gulf of Mexico (Bay of Campeche), some 80 km from Carmen town, Ixtoc 1’s offshore drilling rig, set up by the Perforaciones Marinas del Golfo on behalf of the national company Petroleos Mexicanos (Pemex), was destroyed by the blast of an oil eruption. A fire broke out. This type of accident is quite rare, although it is not one of a kind. Such eruptions have been known to affect Ekofiske Bravo’s oil rig in the Norwegian sea in 1977, Laban island’s well (Iran) in 1971 and Santa Barbara’s well N° 21 (California) in 1969. In each of these cases, the oil eruption was stopped within ten days.
Ixtoc 1’s oil rig on fire (Source IMO)
This
eruption lasted far longer. It was only
stopped
on 23 March 1980, after 295 days, during the which the oil spurt
had been reduced first from 4,200 – 4,300 tonnes/day to
1,400 – 1,500 tonnes/day, thanks to the digging of freeing
pipes which lowered pressure in the implicated well.
The
total quantity of oil spilled at sea will never be known exactly.
The more cautious estimations suggest some
470,000 tonnes were spilled, while in the worst case scenario it
could be as much as 1,500,000 tonnes. Between half and a third of
this oil burned, causing a vast atmospheric pollution. The remaining
part spread over the Gulf of Mexico in the form of drifting slicks.
The
widespread use of dispersants, the settlement of containment booms
and the mobilization of all PEMEX’s recovery means were insuffisant
when faced with such a spill. Oil slicks reached the coast around
Vera Cruz, Tampico, Campeche, Laguna Madre and even as far as Texas.
Shrimp
nurseries, mangroves, beaches and seabirds were oiled. Fishing and
tourist activities were affected.
No
detailed report on the response operations was published. An estimation
of the total cost was made at 1.5 billion dollars, of which 0.4
for the response expenses and 1.1 for the damage. However neither
the Mexican nor the American authorities produced either a scientific
or financial report of the accident.
As
for the Amoco Cadiz’s oil spill, which took place in France
the previous year, Ixtoc 1’s catastrophe led to co-ordination
between operational agencies and research institutes about a global
study of the impact. A committee managed by the National Oceanographic
and Atmospheric Authority (NOAA) was settled to assess the impact
on the whole northwest region of the Gulf of Mexico, including human
health, professional and leisure fishing activities, mammals, birds,
endangered species, as well as economic activities.
Name: Ixtoc 1
Date: 3 June 1979
Location: Bay of Campêche (Mexico)
Accident area: Bay of Campeche, Mexico
Structure type: flat oil shape
Type of pollutant: crude oil
Quantity spilled: 470,000 tonnes
More than 4,000
samples were collected and tested to quantify the extent of the
oil from Ixtoc 1's role in the overall pollution of the Gulf. This
task was made difficult by the fact that the oil
tanker Burmah Agate ran aground and caught fire off the coast
of Galveston in November 1979, which brought further pollution into
an area already hit by a number of disasters.
Slight
alterations in taste in industrial
fishing shrimps
were reported,
but without any quantifiable impact on the resources and their capture.
Slight variations were detected among the sea birds population.
No long term impact was quantified in the areas next to the estuary.
The
study represented more than a demonstration of precise impacts,
and revealed, for future reference, that impact management, execution
and funding procedures must be established before an accident. According
to American experts, this procedure should also include fixing a
value in dollars for each type of ecological damage.
See also
Last update: June 2011