4 Effective Environmental Drilling Methods in British Columbia

Environmental drilling can be a completely new subject for many of us. To define it in simple terms, environmental drilling is a process of collecting soil and groundwater samples to assess the elements of contamination. The data thus collected can be used to develop long-term soil and groundwater monitoring programs and to maximise the production rate for industries.

Drilling methods in British Columbia can vary substantially depending upon the project requirements and location of the job site. However, most underground drilling contractors use the following technique to meet their client’s specific business needs.

1). Direct Push Drilling:

Direct Push drilling is an essential technique widely used in drilling semi-consolidated and non-consolidated subsurfaces. This technique uses small drill rods which advance deeper in the soil with percussion force to soil core samples. Drill cuttings produced during this process are mainly displaced. Direct push rigs can insert analytical equipment into soil formation to determine hydrogeological conditions and the presence of pollutants in a rapid site survey. Direct Push drilling is easy to handle and maintain with a small volume of decontamination waste material.

2). Air or Mud Rotary Drilling:

Air rotary drilling is used to drive deep boreholes in complex formations and works effectively where other drilling methods fail. It penetrates the ground using a rotating bit suspended by a drill pipe and grinds down the surface with little weight applied to advance the borehole. Engineered fluid or compressed air is used to remove the cutting. Rotary drilling is ideal for taking samples from multilayered soil surfaces.

Mud rotary works on the same principles as Air Rotary drilling, The only difference is instead of using air to eliminate drill cuttings, it uses water and other fluids to remove the cuttings.

3). Hollow Stem Auger:

A hollow stem Auger can be a perfect choice for surfaces with softer formations and shallow depths. It uses flighted augers and an aggressive drill bit to dig the formation below. With the rotation of the drilling equipment, cuttings are lifted by the hollow flighted augers, and the bore is stabilised. Many Geotechnical construction companies use the hollow stem auger method to collect samples and understand soil density characteristics. 

A hollow stem auger is less expensive as compared to other drilling methods. Although it is slower than rotary sampling, it facilitates quick selection for sands and clay. Remember that the equipment is not perfect for complex, rocky, and dense formations.

4). Sonic Drilling:

Sonic drilling is a powerful method of collecting samples from the subsurface using high-frequency (50-150 Hz) resonant energy. Sonic drilling significantly reduces the friction by soil liquefaction and makes it easy to penetrate depths of 100 meters or more. The high-frequency mechanical vibration is perfect for collecting high-quality core samples when combined with rotation and down-pressure. The sonic drilling method is highly versatile and can provide continuous core samples of consolidated and unconsolidated ground formations. Reduction in drilling fluids reduces slips and falls and ensures the safety of the crew involved.

Conclusion: 

Comprehensive knowledge of different drilling methods can make a strong foundation for a successful project. Underground drilling contractors employ various innovative and effective Geo environmental drilling methods to assist their clients in their projects. Ask your Geotechnical construction company to help you pick the best drilling technology for your next big project.