7-4.3.3 Costs and Prevention

Prevention of oil spills is given a major priority due to its negative environmental-socio-economic impact. However, the high costs associated with oil spills and regulations governing offshore facilities and operations have necessitated the development of improved technology for efficient spill prevention. The costs of an oil spill can be viewed in both quantitative and qualitative terms of references.

Quantitative costs of an oil spill include the following,

• loss of the oil,
• payment for cleaning up the spill and remediating the environment,
• repair of physical facilities,
• penalties assessed by regulatory agencies,
• expenses in insurance and legal claims.

Qualitative costs of an oil spill include following,

• the loss of pristine habitat,
• biodiversity both known and unknown
• human health effects from exposure to water and soil pollution.

Estimation of the volume of a spill

An oil slick in the open ocean is usually a very thin layer of oil covering a large area. The volume of an oil spill is computed as below;
V_os = A_os X D_os
Where, V_os = Volume of theoil spill,
A_os = Area covered of the oil spill,
D_os = Average thickness of the oil spill.
A_osis measured with satellite imagery and is a fairly a simple and accurate process. Using the image a line around the visible edges of the slick is traced and the area inside the boundary is computed.  For oil spill reports where there is no imagery, the reported length and width of the slick to compute the rectangular area containing the slick is used.
D_ossestimated by observing the color of an oil spill. The thickness is assigned based on established guidelines for the range of thicknesses that can produce a slick of that color (e.g. "Rainbow sheen").