I. LITERATURE REVIEW OF OFFSHORE OIL AND GAS DRILLING
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- Liquid and solid production waste.
- Increased turbidity of the water due to dredging, thus less photosynthesis.
- Seabed disturbance.
- Invasions of certain alien species carried in the ballast water of support vessels. (Steiner, 2003;
Wills, 2002; Patin, 1999).
The risk of pollution linked to the multiple activities of offshore drilling and therefore the
various potential environmental impacts is considerable but at the same time depends on the
overall mode of management of this pollution on the platform. Management must take regulatory
requirements into account but must be adapted to the type of pollution and the specific behavior
of the pollutants. Thus, in the case of accidental pollution, there is urgency and the solutions
provided must be faster. This is the case, for example, of accidental spills linked to the loss of
control of certain operations in the overcooking of sludge on the surface on the platform or at
depth. This risk also exists in the event of uncontrolled discharge of drilling waste into the sea as
well as during their transport to land.
I.4.2.1 Emissions to water and marine sediments
Potential emissions of pollutants into the marine environment can occur throughout the life cycle
of this industrial activity but are greatest during these stages:
- Emissions to water and marine sediments that are related to circulation losses during well
drilling. It is a mixture of pollutants including hydrocarbons, metals, salts and other toxic
substances due to the composition of drilling fluids. The metals may be of natural origin since
they were initially found in the cuttings of rocks drilled from the different geological layers
crossed. The highest total contents in the cuttings are therefore linked to the local geochemical
background. The total contents of these pollutants depend both on the volumes of loss, on the
variable composition of the fluids for each section or section of the well and finally on the depth
of the well. The local physico-chemical and bathymetric conditions play a key role in the
behavior of these pollutants by promoting their transfer and/or certain biogeochemical processes
such as bioturbation, biodegradation (aerobic or anaerobic), chemical speciation, bioavailability
and bioaccumulation.
- Emissions to the air and their atmospheric deposition, either in the area of the offshore platform
on the surface of the water or further offshore or on land depending on the winds and the size of
the particles emitted.
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- Liquid and solid production waste.
- Increased turbidity of the water due to dredging, thus less photosynthesis.
- Seabed disturbance.
- Invasions of certain alien species carried in the ballast water of support vessels. (Steiner, 2003;
Wills, 2002; Patin, 1999).
The risk of pollution linked to the multiple activities of offshore drilling and therefore the
various potential environmental impacts is considerable but at the same time depends on the
overall mode of management of this pollution on the platform. Management must take regulatory
requirements into account but must be adapted to the type of pollution and the specific behavior
of the pollutants. Thus, in the case of accidental pollution, there is urgency and the solutions
provided must be faster. This is the case, for example, of accidental spills linked to the loss of
control of certain operations in the overcooking of sludge on the surface on the platform or at
depth. This risk also exists in the event of uncontrolled discharge of drilling waste into the sea as
well as during their transport to land.
I.4.2.1 Emissions to water and marine sediments
Potential emissions of pollutants into the marine environment can occur throughout the life cycle
of this industrial activity but are greatest during these stages:
- Emissions to water and marine sediments that are related to circulation losses during well
drilling. It is a mixture of pollutants including hydrocarbons, metals, salts and other toxic
substances due to the composition of drilling fluids. The metals may be of natural origin since
they were initially found in the cuttings of rocks drilled from the different geological layers
crossed. The highest total contents in the cuttings are therefore linked to the local geochemical
background. The total contents of these pollutants depend both on the volumes of loss, on the
variable composition of the fluids for each section or section of the well and finally on the depth
of the well. The local physico-chemical and bathymetric conditions play a key role in the
behavior of these pollutants by promoting their transfer and/or certain biogeochemical processes
such as bioturbation, biodegradation (aerobic or anaerobic), chemical speciation, bioavailability
and bioaccumulation.
- Emissions to the air and their atmospheric deposition, either in the area of the offshore platform
on the surface of the water or further offshore or on land depending on the winds and the size of
the particles emitted.