The feet of drawdown in a well is defined as:

The feet of drawdown in a well is defined as the distance between the static groundwater level and the pumping level. This measure is crucial because it indicates how much the water level in the well drops when water is being extracted by pumping. During normal conditions, the static groundwater level represents the natural height of the water in the well when it is not being pumped. When pumping occurs, the water level falls to a lower point, referred to as the pumping level. The difference in these two levels — the static level and the pumping level — is what constitutes the drawdown.

Understanding drawdown is essential for water operators as it helps assess the sustainability of a well, evaluate the aquifer's response to pumping, and design efficient pumping systems. Monitoring drawdown also helps in identifying potential issues, such as over-extraction or aquifer depletion.

The other options pertain to different concepts related to groundwater and wells but do not accurately reflect the definition of drawdown. For instance, the first option speaks about the distance between static groundwater level and water table, which is not relevant in defining drawdown.