What does the term "annular space" refer to in drilling?

The term "annular space" specifically refers to the area between the borehole (or drill hole) and the casing pipe that is installed within it. This space is crucial in drilling operations as it plays a significant role in well construction and water well integrity.

This annular space allows for the circulation of fluids used during drilling operations, provides a pathway for the chemical and physical processes involved in well development, and aids in ensuring that contaminants do not migrate from the surface into the groundwater supply. Proper management of this space is essential for maintaining the quality of the water being accessed through the well.

Understanding this definition is pivotal for water well contractors as it informs their practices related to sealing and installation techniques, which are vital for safeguarding groundwater aquifers from potential contamination.