How many oil spills have happened?

Answer 1

four types as categorized by the EPA (plus non-petroleum, synthetic)

Class A Oil

• Class A oil is light and fluid, spreads quickly when spilled and has a strong odor. Class A oil is the most toxic but least persistent of all oils. If the oil soaks into the soil, the effects will be long lasting. In water, class A oils disperse readily but affect aquatic life in the upper water column. Class A oils include high-quality light crude oils as well as refined products such as gasoline and jet fuel. Toxic components of gasoline include benzene, a known carcinogen, and hexane, which can damage nervous systems in humans and animals.
• Class B Oil
• Class B oils are known as "non-sticky" oils. They are less toxic than class A oils but more likely to adhere to surfaces. According to the U.S. Fish and Wildlife Service, they can cause long-term contamination. Lower-quality light crude oils and refined products such as kerosene and other heating oils fall into class B. Class B oils leave a film on surfaces, but the film will dilute and disperse if flushed vigorously with water. Class B oils are highly flammable and will burn longer than class A oils.
• Class C Oil
• Class C oils are heavy and sticky. While they do not spread as quickly or penetrate sand and soil as easily as lighter oils, class C oils adhere strongly to surfaces. Class C oil does not easily dilute and disperse, making it especially detrimental to wildlife, such as fur-bearing marine mammals and waterfowl. Because it produces such a sticky film, a class C oil spill can severely contaminate intertidal zones, leading to expensive, long-term cleanups. Class C oils include most types of crude oil and bunker B and bunker C fuel oils. Such oils are prone to forming lumps of oil or emulsions.
• Class D Oil
• Class D crude oil is solid and has the least toxicity. The biggest environmental concern posed by class D oil occurs if the oil is heated and hardens on a surface, making cleanup nearly impossible. The U.S. Environmental Protection Agency points out that as the volatile components of some oils evaporate they may leave behind class D residues.
• Non-Petroleum Oil
• Synthetic oils and oils derived from plant or animal fats are regulated by the EPA because they cause contamination if released into the environment. Non-petroleum oils coat wildlife and can cause death due to suffocation or dehydration. Non-petroleum oils are slow to break down and easily penetrate soil, causing long-lasting damage to an affected area. Examples of non-petroleum oil products include cooking fats and synthetic oils.

• Read more: Types of Oil Spills | eHow.com http://www.ehow.com/list_6593214_types-oil-spills.html#ixzz13XGv1nwB

copy-paste =) hope that helped

Answer 2

I looked this up to find your answer and it is several answers. According to US data from 1970-1990 it was 4 barrels per year that were at least 50 barrels. ( one barrel equals 42 gallons. This number went up. In years 2005-2009 it was up to 22 spills per year of at least 50 barrels. My impression was that anything smaller than 50 barrels wasn't counted, so these numbers are not very accurate and do not count all spills.

Answer 3

The two major ones in recent history are the Exxcon Valdez spill and the BP Gulf Spill.

Answer 4

100

Answer 5

87

Answer 6

69