Hydrologic balance
Hydrologic balance means the relationship between the quality and quantity of water inflow to, water outflow from, and water storage in a hydrologic unit such as a drainage basin, aquifer, soil zone, lake, or reservoir. It encompasses the dynamic relationships among precipitation, runoff, evaporation, and changes in storage of groundwater and surface water, as well as interactions that result in changes in the chemical composition or physical characteristics of groundwater and surface water.
Source
30 CFR § 701.5
Scoping language
As used in this chapter, the following terms have the specified meanings, except where otherwise indicated: