Darcy's Law states that the flux of water through a porous medium is proportional to the hydraulic gradient.

The hydraulic head is a measure of the total energy of groundwater at a point and is the sum of the elevation head and the pressure head.

Transmissivity is a measure of the aquifer's ability to transmit water and is calculated by multiplying the hydraulic conductivity by the aquifer thickness.

Specific yield is the volume of water that an aquifer can release from storage per unit volume of aquifer material.

Storage coefficient is the volume of water that an aquifer can release from storage per unit decline in hydraulic head.

Groundwater flow is primarily driven by differences in hydraulic head, which cause water to move from areas of higher head to areas of lower head.

In an unconfined aquifer, the water table is the upper surface of the saturated zone, where the pressure head is equal to atmospheric pressure.

In a confined aquifer, the water pressure is greater than atmospheric pressure throughout the aquifer, preventing the formation of a water table.

Aquifers are typically composed of sand, gravel, or fractured rock, which have high porosity and permeability, allowing for the storage and movement of groundwater.

Groundwater recharge occurs when water from the land surface infiltrates into the ground and reaches the water table, replenishing the aquifer.

Groundwater discharge occurs when water flows out of an aquifer and into a surface water body, such as a river or lake, releasing water from the aquifer.

Groundwater flow can be affected by human activities, such as pumping from wells or the construction of dams, which can alter the hydraulic gradient and groundwater flow patterns.

Groundwater contamination can occur from various sources, including industrial activities, agricultural practices, and improper waste disposal, leading to the degradation of groundwater quality.

Groundwater management involves the sustainable use and protection of groundwater resources to ensure their long-term availability, considering factors such as recharge, discharge, and contamination.

Groundwater models are mathematical representations of groundwater flow and can be used to simulate and predict groundwater behavior under different scenarios, aiding in groundwater management and decision-making.