What is the purpose of a septic system installation?

• A. Generating electricity from waste
• B. Filtering drinking water for city
• C. Landscaping of property
• D. Waste disposal at individual and commercial dwellings that don't have sanitary sewers available

Answer: (D)

Septic systems are designed for on-site wastewater treatment where there is no sanitary sewer available. Wastewater from sinks, toilets, and showers goes into a septic tank, where solids settle and scum forms. The clarified liquid then moves to a drain field, where soil and microorganisms treat it before it reaches groundwater. This setup provides waste disposal for individual or commercial properties without sewer connections and protects health and the environment by handling wastewater locally. The other options don’t describe this function: generating electricity from waste isn’t the typical goal of a septic system, filtering drinking water for a city is a municipal treatment task, and landscaping is unrelated to wastewater management.