3 Questions to Consider when Choosing a Drilling Technology

When it comes to environmental and geotechnical drilling, selecting the right technology is foundational to project success. With a wide range of drilling methods available—each suited to different site conditions and objectives—how do you determine which one is the best fit?

Before diving into the specifics of each method, it’s essential to understand the core principles that underpin all drilling technologies. Whether you're a seasoned project manager or new to the field, asking the right questions can help you make informed, confident decisions. 

First, Ask the 3 Big Questions

There are three fundamentals that almost all drilling methods share. If you’re able to answer these three fundamental questions about the particular drilling technology then you clearly understand it and are able to determine whether or not it’s suitable for a particular job site. The three questions are:

What is the Method of Penetration?

How do you physically cut through the soil? If you’re digging in your backyard, the method of penetration is putting weight on the spade of the shovel to cut into the dirt. Of course, with environmental and geotechnical drilling, the method of penetration is typically much more sophisticated than a shovel.

How are the Cuttings Removed from the Boring?

Sticking with our shovel example, the dirt in that hole is removed a shovel-full at a time and set aside. Each drilling method has a specific way of removing cuttings from the boring, and that’s one of the main aspects that differentiates one drilling method from another in terms of applicability.

How is the Boring Stabilized?

In our backyard hole, you’re relying on the natural confidence of the formation to keep that hole open. If you’re drilling a 300 feet deep hole that's 8 inches wide, you’re likely going to need another method of keeping that hole open. Methods of stabilization vary by drilling technology.

These are the three fundamental characteristics of almost all drilling methods, and these questions are the primary means of determining a particular drilling method for a given site.

The Method is Independent of The Rig

One of the most important—and often misunderstood—concepts in drilling is the distinction between the method and the rig. While they’re closely related, they are not interchangeable.

Think of it this way: the drilling method is the how—the technique used to penetrate the subsurface, remove cuttings, and stabilize the borehole. The rig, on the other hand, is the tool—the equipment or platform used to deploy that method. Understanding this distinction is critical for selecting the right approach for your project.

Here’s why:

• Drilling technology is driven by geology and project objectives. The subsurface conditions and data collection goals will determine which method is most appropriate.
• Rig selection is based on site constraints. Surface access, terrain, and logistical limitations often dictate which rig can be used.
• Many methods are compatible with multiple rigs. For example, a sonic drilling method can be deployed using different rig types depending on the site setup.

In the field, it’s common to refer to a rig by the method it typically performs—but for planning and technical accuracy, it’s important to separate the two. This clarity helps ensure the right combination of method and rig is selected to meet both the technical and practical demands of the project. 

Choosing the right drilling technology starts with asking the right questions. By understanding how a method penetrates the subsurface, removes cuttings, and stabilizes the borehole, you can more confidently evaluate whether it’s the right fit for your project. And don’t forget—the drilling method and the rig are distinct. Keeping that distinction clear helps ensure smarter planning and better outcomes.

Want to deepen your understanding of drilling methods and how to apply them in the field? Explore our on-demand webinar series, where we break down the fundamentals and real-world applications of drilling technologies. It’s a great resource whether you're new to the industry or brushing up on the basics.

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