Page 353 - Drilling Technology in Nontechnical Language

344 Drilling Technology in Nontechnical Language, Second Edition

After the well has finished, the pit is allowed to dry out. This can take

several weeks, even in the desert. Once it has dried, the pit is recovered
with the originally extracted earth and the site is restored. In many cases

the wellhead can be visited, and it is difficult to tell where the waste pits
used to be.
Sewage pits are also dug and pipes are run from the accommodations
to this pit. As with the rig waste pit, this is allowed to dry out before being
covered over and the site restored.

Inadvertent spills

Sometimes an accident or incident will occur that places large volumes

of polluting fluids into the environment. This may be crude oil, rig fuel, oil-
based mud, or some other liquid pollutant. This will initiate a preplanned
spill response that may involve other operators in the area, the coast guard,
and other public agencies and various contractors.
In many areas, the operators active in the area get together and share the
cost of a spill response team. Equipment is stored in areas where response
vessels can quickly load up and head out to the area. This equipment will
include booms (to contain the spill), pumps, tanks, and chemicals.
To have all this equipment standing by costs quite a lot of money.
Hopefully, it will never be needed, but nevertheless it is part of the
operators’ responsibility to be prepared.

Environmental Impact Studies

Even in areas that are not especially sensitive, many operators carry

out studies to gauge the impact of their operations on the flora, fauna,
and aquatic life around the operation. This assessment will cover not only
the result of normal operations but also what would happen if an oil spill
occurred. The effects of prevailing winds and currents will be studied to
see which areas would be at greatest risk of a landfall so that contingency
plans can be drafted.
In sensitive areas, public enquiries might be held so that the public can
understand the operator’s plans and can comment and raise concerns.

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