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What is the difference between a septic tank and a sewage treatment plant?
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The primary difference between a septic tank and a sewage treatment plant is that a septic tank is designed to treat waste water from a single residence, while a sewage treatment plant is designed to process wastewater from multiple residences or businesses. A septic tank generally contains layers of gravel, sand and soil that allow for bacteria in the wastewater to break down organic matter into carbon dioxide and water. These tanks are then periodically emptied by a professional who will remove the solids from the tank before disposing of them at an approved disposal site. On the other hand, a sewage treatment plant typically uses a combination of physical, chemical, and biological processes to remove pollutants from wastewater. This type of system usually includes several steps such as screening, grit removal, primary sedimentation, secondary sedimentation, disinfection, and finally discharge into a natural body of water.