Once the studies are terminated and the decision to drill taken, the drilling equipment must be installed at the location selected on the prospect maps. The co-ordinates of the locations are very precise, but the place on the ground that corresponds is not always easy to prepare. For that, a site study is undertaken, without forgetting the impact study, that is to say a complete inventory of the site before work starts (environmental impact …). At sea, the depth of the water is measured and the seabed studied to find out, for example, if it can support the piles for a drilling platform. Equally, certain climactic data are studied: wind force, wave height, strength of currents. The necessary steps are taken to know the worst extremes of bad weather that are possible, in order to protect the installations from the worst storms. In certain closed seas sheltered from the extremes of bad weather, such as in the Netherlands, the drilling sites are surrounded by a veritable wall that avoids any contamination of the sea by waste or by polluting products. On land, obstacles can be found: inhabited zones, very uneven broken land, marshy areas… Those responsible for the site study determine the location that is the safest and the nearest possible to the co-ordinates planned.
Then roads are constructed to bring in the equipment and to take it out at the end of drilling. On the site itself, the areas intended for the drilling operations, the technical buildings and accommodation are cleared of trees and undergrowth, raked, flattened and cleaned.
Setting up the site takes several days. At sea, the equipment used (drilling platform or boat) is brought to the site by tugs, or arrives under its own power. During the drilling period, a major logistics operation is maintained. The site must be supplied with equipment (drilling pipes, tubing), with products for the mud and with food for the personnel. The replacement of teams who go on rest leave must be planned, as must the comings and goings of people whose presence is not permanently necessary (shuttles on land and helicopters at sea).
At the end of drilling, the site must be restored to the state it was in before the work began. All pollution must be cleaned up, and, in particular, any quagmire must be carefully eliminated (residues of used drilling mud full of polluting matter), so that it doesn’t spread into the surrounding nature. Sometimes vegetation is replanted so that the site recovers its appearance prior to drilling.
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