Define groundwater and list some anthropogenic (human) sources of groundwater pollution. Why do many scientists consider groundwater pollution a greater problem than surface water pollution? Describe and explain the major steps in the process of wastewater treatment. How can artificially constructed wetlands aid such treatment?

Groundwater : The water which is present inside the earth is known as ground water.

Some anthropogenic (human) sources of groundwater pollution are the following:

1) Use of chemicals for plants i. e. Herbicide and insecticide.

2) leaching of fertilizers in the field that is used by farmers.

Scientists consider groundwater pollution a greater problem than surface water pollution because ground water is used for drinking purpose.