Environmental engineering focuses on the design, construction, and operation of systems and processes that protect human health and the environment from the adverse effects of human activities.

The activated sludge process is a biological wastewater treatment process that uses microorganisms to break down organic matter and remove pollutants from wastewater.

Air pollution control devices are designed to remove particulate matter, gaseous pollutants, and other harmful substances from the air before it is released into the atmosphere.

Renewable energy sources are those that can be replenished naturally on a human timescale, such as solar energy, wind energy, and hydroelectric energy.

Recycling is the process of converting waste materials into new materials and objects, thereby reducing the amount of waste that is disposed of in landfills or incinerators.

Crop rotation, integrated pest management, and conservation tillage are all practices that can help to reduce the environmental impact of agriculture by reducing soil erosion, water pollution, and the use of pesticides and fertilizers.

An environmental impact assessment is a process that evaluates the potential environmental impacts of a proposed project or activity, and identifies measures to mitigate those impacts.

Green infrastructure, low-impact development, and rain gardens are all practices that can help to control water pollution from stormwater runoff by reducing the amount of runoff and filtering pollutants from the water.

Bioremediation is the process of using microorganisms to break down and remove pollutants from soil and groundwater.

Catalytic converters, diesel particulate filters, and hybrid electric vehicles are all technologies that can help to reduce air pollution from vehicles by reducing the amount of pollutants emitted from the exhaust.

Natural resource management, conservation, and sustainability are all terms that refer to the process of managing and protecting natural resources for the benefit of present and future generations.

Energy efficiency, renewable energy, and carbon capture and storage are all technologies that can help to reduce greenhouse gas emissions by reducing the amount of fossil fuels that are burned.

Life cycle assessment is a process that evaluates the environmental and social impacts of a product or service throughout its entire life cycle, from raw material extraction to final disposal.

Green building, sustainable construction, and low-impact development are all practices that can help to reduce the environmental impact of construction activities by reducing energy consumption, water use, and waste generation.

Environmental policy, environmental management, and sustainability are all terms that refer to the process of developing and implementing strategies to protect and improve the environment.