Which aspect is included in a sanitary survey of groundwater supplies?

A sanitary survey of groundwater supplies encompasses a comprehensive evaluation of various factors that can impact water quality and safety. The inclusion of the aquifer drainage area and local geology is essential as it helps to understand the natural filtration process and potential contamination sources that may affect the groundwater.

The nature of soil and rock strata is also critical because these characteristics influence how water moves through the ground and how contaminants may be transported or filtered. Different types of soil and rock can have varying capacities to either protect groundwater from or expose it to pollutants.

Assessing land use and habitation is vital to identify potential sources of pollution, such as agricultural runoff, industrial discharges, or waste disposal sites. Understanding how human activity interacts with the local geology further informs the sanitary survey by highlighting risks to groundwater from surrounding areas.

By considering all these aspects, the sanitary survey paints a complete picture of the factors that can affect groundwater quality, emphasizing the environmental health professional's role in ensuring safe drinking water. Therefore, all the factors mentioned contribute to a thorough understanding of the groundwater's safety and sustainability, making the comprehensive answer the most appropriate choice.