What does a well log typically document?

A well log is a crucial document in the context of water wells as it provides comprehensive information regarding both the geological strata encountered and the construction details of the well itself. This includes details such as the types of materials present at various depth intervals, the depth to the water table, and the construction features of the well, like casing, screen intervals, and any methods used for well development.

This documentation is essential for various reasons: it aids in understanding the subsurface geology, which can influence groundwater flow and well productivity. Additionally, it serves as a historical record of the well construction, which is valuable for maintenance or in the event of future issues. Therefore, the correct answer accurately reflects the purpose and content of a well log, ensuring that the information provided is thorough and useful for water resource management.

While the other options mention important aspects related to a well, they do not encompass the extensive range of data that a well log typically includes. The depth of the well, the cost of drilling, and water quality test results are certainly relevant considerations but are not the comprehensive scope that a well log documents.