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expenses.
The operating company takes several steps before telling the drilling contractor exactly
where to place the rig and start, or spud, the hole. The company carefully reviews and analyzes
seismic records. Legal experts thoroughly examine lease terms and agreements. They ensure that
the operating company has clear title and right-of-way to the site. Surveyors establish and verify
exact boundaries and locations. The company also confirms that it has budgeted the necessary
drilling funds and that the funds are available.
On land, operating personnel usually try to choose a spot directly over the reservoir. With
luck, the surface will be accessible and reasonably level. They also try to pick a location that will
not suffer too much damage when the contractor moves in the rig. In an area that is especially
sensitive, the operator and contractor take extra steps to ensure that as little harm as possible occurs.
Offshore, the operator hopes that the weather is reasonably good, and, if using a bottom-supported
rig, picks a spot where the ocean bottom (the mud line) can adequately hold any rig supports in
contact with it.
PREPARING THE SITE

On land sites, the operator hires a site-preparation contractor to prepare the location to
accommodate the rig. If required, bulldozers 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 removes any harmful material that may be in the pit and properly disposes of it. A
bulldozer then covers it with dirt and levels it. If necessary, the contractor lines а reserve pit with
plastic to prevent soil and groundwater pollution. In especially sensitive areas, such as in a
migratory bird flyway or in a wildlife refuge, contractors cover the pit with netting to prevent birds
from landing in it. In addition, they may put up a fence to keep cattle or wildlife out.
In some areas, reserve pits are rare. Offshore, and on sensitive land locations, the contractor
places cuttings in portable receptacles and disposes of them at an approved site. Most operators and
contractors recycle as many drilling mud components and other materials as possible. What they
cannot recycle, they discard at approved sites. In some areas, regulatory agencies enforce a zero-
discharge policy. This policy prevents anyone from emitting anything onto the ground, into a
waterway or estuary, or into the sea.

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