Which of the following is a correct statement about the driller's log information?

• A. Depth to water
• B. Odors from cuttings
• C. Loss of drilling fluid
• D. Water temperature

Answer: (A)

Depth to water is the essential datum recorded in a driller’s log because it identifies where groundwater is encountered in the borehole, effectively marking the water table depth at the time of drilling. This information is central to planning and designing the well: it helps determine static water level, where to place the well screen and intake, and how much casing or surface protection is needed. While other notes like odors from cuttings, drilling-fluid losses, or water temperature may be observed or recorded as supplementary field notes, they do not define the groundwater encounter or drive the fundamental design decisions the log supports.