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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.

Cellar

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