Too much water too fast to be retained. Not much groundwater recharge because the water is there and gone so fast. Soil has a lot of humus in it that spongy and slows water down. The water that makes it through the humus sinks down and raises the groundwater. Overtime, the soluble stuff in the water dissolves. Extreme chemical weathering leaches the soil and regolith (heat and water required) Bauxite is what is left (aluminum oxide ore) It takes a large amount of power to convert aluminum oxide ore to aluminum metal; quebec has cheap hydropower. Decline of lake level in florida due to pumping of groundwater from the florida aquifer. Decline of the water table in the high plains aquifer as a result of agricultural use of groundwater. Sustainable year to year, but not over time. Oases in the sahara develop from spring flow. Water from recharge areas flows to oasis discharge points.