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the Marine Environment from Land-based Activities (GPA) and the Washington
Declaration (1995) implemented by the United Nations Environment Programme
(UNEP).
The Paris Convention seeks to prevent and eliminate pollution
and to protect maritime
areas against the adverse effects of human activities.
In addition, each of the regional seas has its own convention or action plan; in
particular, the Helsinki Convention (HELCOM) refers to protection of the Baltic and
the Kattegat Seas.
(d) International Targets/Recommended Standards: Some regional targets exist.
(e) Linkages to Other Indicators: This indicator is linked to
indicators for oil and
gas production, consumption and import. It is also linked to other environmental
indicators related to contaminant discharges in water,
greenhouse gas emissions, air
pollutant emissions, etc.
METHODOLOGICAL DESCRIPTION
(a) Underlying Definitions and Concepts: Oil pollution in coastal waters essentially
takes
place in two ways, either as large discharges during a short period owing to
accidents (acute discharges) or as small but continual discharges over a longer period
(chronic or diffuse discharges). It is estimated that 1% of the total amount of oil
transported by sea is discharged.
There are multiple sources of oil pollution in coastal areas and marine environments.
The major sources include the following:
• Discharges
from coastal industries; for example, petrochemical and oil
refineries, and factories using oil-based products as feedstock.
• Discharges from coastal iron, steel
and non-ferrous industries, as well as from
engineering and surface treatment industries that use oil in various processes
and operations.
• Discharges and overflows of storm water,
which often contain oil, soot,
grease, etc.
• Discharges of diffuse inputs from various sources.
• Shipping accidents at sea that release oil.
• Accidents in connection with oil and gas production, such as blowouts,
explosions and fires.
• Discharges from ships in operation, including
legal as well as illegal
discharges (e.g. tank cleaning at sea, which is prohibited).
• Recurrent discharges entering the sea around oil platforms from drilling muds
and oil production water.
• Spills during the loading or unloading of crude oil and petroleum products,
refuelling and other port operations.
• Atmospheric deposition.
