Excavation Site Preparations

There are several necessary steps that site preparation contractors and their crew must do in order to begin an excavation project. Once the location for the site is established, the area is prepared for drilling. These steps, though they are not visible after the project is over, are essential. Contractors and workers in charge of site prep face various hazards and should take the necessary precautions to ensure their safety.

LEVELING THE SITE

During this first stage of preparation, the site is leveled (if necessary) with a bulldozer and/or a grader. During this process, there is potential for damage to buried pipelines, unpredictable weather changes, potential for contact with irritant and toxic plants and an uneven ground may cause the bulldozer to roll. Here are some possible solutions to these hazards:

• Perform a site line location survey
• Plan for hazards due to unpredictable changing weather
• Protect employees engaged in site clearing from irritant and toxic plants by teaching them first aid treatments
• Provide rollover guards on all equipment used
• Provide overhead and rear canopy guards on rider-operated equipment

EXCAVATING & TRENCHING

The scale and duration of excavating and trenching are very minor and site-specific. On some drilling sites, a below ground-level cellar may be excavated in which the borehole is drilled. Also, a reserved pit and settling pit may be dug and used for water or fluid discharges.
In this stage, there is a risk for respiratory problems caused by dust and other airborne contaminants, and again, a risk in damaging pipelines and cables. Here are some possible solutions for hazards in this stage of the process:

• Wear appropriate respiratory protection
• Perform a site line location survey

CONDUCTOR HOLE AND CONDUCTOR PIPE

Prior to commencing the rig-up progress, the conductor, rathole and mousehole are completed. In certain circumstances, special companies may be hired to begin drilling these three holes.
The conductor hole (sometimes called the starter hole) is a large diameter hole that is lined with pipe. It varies in length depending on the local geology. In this stage of the process, workers are at risk of being struck by the hoisting line, suspended drill or casing. Here are some possible solutions for hazards in this stage of the process:

• Wear personal protective equipment (PPE) such as a hard hat, glasses, safety toe boots and work gloves

RATHOLE

A rathole is a hole in the rig floor that is 30 to 35 feet deep and is lined with casing which projects above the floor. Then, the kelly is placed when hoisting operations are in progress. This is either done by the portable rig that drills the conductor hole, or may be done by the primary rig after rigging up.
At this stage, workers run the risk of falling or stepping into an uncovered mousehole. Do the following to prevent injury:

• Cover the hole until it is lined with casing or other material during rigging-up

TRANSPORTING EQUIPMENT VIA TRUCKS

Depending on the location of the excavation site, access may require preparation of a roadbed. The site and its access road must accommodate a large number of temporary and semi-permanent structures and tanks. All of these materials are transported with trucks. During this part of the process, equipment is loaded on trucks at a previous drill site or storage yard and transported to the new drill location.
In this stage, the soil at the new drill site may not be compacted sufficiently to support incoming loads, which may cause the load to become unstable. In addition, the load may not be secured properly causing it to shift or the tie-downs to fail and the truck may slide off the road in slick conditions. Do the following to prevent accidents:

• Make sure the access road and drill pad have been properly prepared before driving on it
• Drive slowly and be cautious on shifting weight
• Tie down loads with proper devices and inspect them before traveling

UNLOADING AT THE DRILL SITE

Once workers are at the new drill site, they must unload the equipment and place it approximately where it will be rigged up. During this stage of the process, improperly secured loads could cause equipment to slide or collapse during unloading. Do the following to prevent accidents:

• Inspect the loads before loading and unloading