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clear and level the аrea. This contractor also builds an access road and,
if necessary, a turnaround. Offshore, the operator simply marks the
spot with a buoy. On all jobs, contractors and operators make every
effort to keep damage to a minimum because no one wishes to harm
the environment. Further, if harm does occur, the contractor and
operator have to pay to correct or mitigate the damage, which can be
expensive.

Surface Preparation

The contractor uses various materials to prepare the surface
and roads around a land location. Near the coast, oyster shells are
popular. In other locations, gravel may be the choice. A contractor
may lay boards to allow access in rainy weather. In the far north,
permafrost presents a special problem because the heat generated
under and near the rig may melt the permafrost. Thus, the rig may
settle into the thawed soil. In permafrost, therefore, the contractor
spreads a thick layer of gravel to insulate the area. If gravel is scarce,
polyurethane foam may be used.

Reserve Pits

At a land site, the site-preparation contractor may dig a reserve
pit. А reserve pit is an open pit that is bulldozed from the land next to
the rig. Reserve pits vary in size, depending on how much room is
available at the site. Usually, reserve pits are relatively shallow,
maybe no more than 10 feet (3metres) deep and are open on top. In
the early days of drilling, the reserve pit was mainly a place to store a
reserve supply of drilling mud. Today, however, drilling mud used in
actively drilling the hole is seldom stored in the reserve pit, although,
in an emergency, it can be.
Modern reserve pits mainly hold rig wastes temporarily. For
example, cuttings carried up the hole by the drilling mud fall into the
reserve pit. After finishing the well, the drilling contractor or operator

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