Auger drilling is a popular choice for projects like groundwater sampling, installing electric utility poles, or even conducting mining geoprobes. The great speed and relatively low cost of this type of drilling make it a common tool, but the same piece of equipment won’t necessarily be suitable for every location. Soil conditions are ultimately the deciding factor in determining what type of auger equipment should be used.

Softer Dirt

For softer soil conditions, digger derricks are typically used. These drills can create holes up to 10 feet deep with a diameter of 42 inches. Digger derricks are often used in conjunction with more powerful auger drilling. The auger drill, which can achieve up to 80,000 lbs of torque, will prepare the hole, while the digger derrick then refines the hole and sets other objects in place. Even in soft soil conditions, a digger derrick is still relatively limited. Any hole greater than 10 feet deep will require auger drilling. 

Getting Through Rock

Dirt augers may be able to create large, deep holes, but they aren’t suitable for cutting through rock. Typically, most contractors will start by digging with a dirt auger until they reach a hard rock layer. Then, the switch is made to a more powerful rock auger. For especially tough conditions, such as reinforced concrete or non-fractural rock, a core barrel will likely be used instead of a traditional spiral tool. 

Hard rocks like granite require extra caution, as attempting to drill too quickly could damage the auger. In these situations, slow, cautious drilling is essential. It should also be noted that core barrels are also available for digger derricks when a smaller hole is needed.

If you’re in need of reliable auger drilling, turn to GeoTek Alaska in Anchorage, AK. Providing accurate and cost-effective subsurface analyses since 2002, their team uses a wide variety of drills and sensors to achieve quality results. They can even fly in equipment to reach remote locations. To learn more about their services, visit them online or call (907) 569-5900.