During drilling, which of the following is a typical item recorded on site logs?

• A. Lithology notes
• B. Chemical analysis report
• C. Sample chain-of-custody
• D. Pumping test results

Answer: (A)

During drilling, the logs focus on describing what is physically encountered in the borehole as it is being drilled. The most common entry is lithology notes, which record the actual rock or soil types encountered at each depth interval, including things like color, grain size, texture, moisture, presence of lithologic changes, and any notable features such as fractures or zones of loose material. These observations form the core of the borehole or site log because they directly document the stratigraphy the borehole passes through and help guide decisions about sampling, well construction, and interpretation of groundwater conditions.

The other items—chemical analysis results, chain-of-custody details, and pumping test results—are typically generated from samples or tests that occur after the initial drilling and sampling phase. Chemical analyses are lab work performed on collected samples; chain-of-custody records track sample handling and transfer rather than field observations; pumping test results come from dedicated tests conducted to evaluate well performance, usually after the borehole has been drilled and constructed.