Courses : Forest Ecology Lecturer :Frischa Adellia Semester : 4thSemester, 2022/2023 Session Definition of Landfill A landfill or final disposal site is a location specifically designed to receive, contain and manage solid waste safely. This is one of the main methods for managing solid waste generated by human activities, such as domestic, commercial, industrial and construction waste. In a landfill, waste is processed and stored in a certain area that has been carefully designed and managed so as not to pollute the surrounding environment. Some characteristics of landfills include: 1. Containment layer: Landfills usually have a containment layer at the bottom to prevent infiltration of waste into the soil below. This layer consists of waterproof geomembrane or clay material. 2. Gas collection system: Organic waste that decomposes in landfills can produce dangerous gases such as methane. Therefore, landfills are usually equipped with a gas collection system to capture and process these gases. 3. Waste water management: Rainwater that flows through waste in landfills can become polluted and become leachate. Therefore, landfills have a leachate collection and management system to prevent environmental pollution. 4. Solid waste management: Solid waste is placed in cells or "gutters" within the landfill, then covered with a layer of soil after each filling stage to reduce the potential for contamination. 5. Monitoring and management: Landfills must be monitored regularly to ensure that the waste disposed of does not pollute the surrounding environment. This involves monitoring the quality of groundwater, air, and soil around the landfill. Landfills are usually used as a final waste disposal option when processing or recycling methods are not feasible or economical. Despite being one of the most commonly used methods, landfills also have risks to the environment if not managed properly, such as soil, water and air pollution. Therefore, strict regulations are needed to manage and operate landfills safely. The following are some examples of well-known landfills in various countries: 1. Puente Hills Landfill, United States : Located in California, Puente Hills Landfill is one of the largest landfills in the United States. This landfill serves the Los Angeles area and its surroundings, and has been operating since 1957 until it closed in 2013. When operating, this landfill accommodated approximately 13.2 million tons of waste per year. 2. Bantar Gebang Landfill, Indonesia : Bantar Gebang Landfill is located in Bekasi, West Java, and is one of the largest landfills in Southeast Asia. This landfill serves the city of Jakarta and its surroundings. Bantar Gebang Landfill has been operating since 1989 and has an area of around 110 hectares. 3. Fresh Kills Landfill, United States: Located on Staten Island, New York City, Fresh Kills Landfill was one of the largest landfills in the world before it closed in 2001. It held most of the waste generated by New York City for decades. Once closed, the plan is to turn the land into a public park. 4. Olusosun Landfill, Nigeria : Located in Lagos, Olusosun Landfill is the largest landfill in Nigeria and is considered one of the largest in Africa. This landfill serves the city of Lagos and its surroundings. Unfortunately, Olusosun Landfill is often an unorganized landfill and has serious problems with air and soil pollution. 5. Wagland Landfill, Australia : Located in Melbourne, Victoria, Wagland Landfill is one of the largest landfills in Australia. This landfill serves the city of Melbourne and the surrounding area. The local government is making various efforts to reduce the environmental impact of this landfill, including the use of gas processing technology. These are just a few examples of world-famous landfills. Landfills are an important component of modern waste management systems, although there are ongoing efforts to reduce reliance on these methods through recycling, waste processing, and the use of energy alternatives. In conclusion, landfills or final disposal sites are important infrastructure in modern waste management that are used to accommodate and manage solid waste safely. Landfill is used when processing or recycling methods are not possible or uneconomical. Some examples of well-known landfills in various countries include Puente Hills Landfill in the United States, Bantar Gebang Landfill in Indonesia, Fresh Kills Landfill in the United States, Olusosun Landfill in Nigeria, and Wagland Landfill in Australia. Although landfills are a commonly used final disposal solution, they also pose risks to the environment if not managed properly. Soil, water and air pollution as well as the potential formation of toxic gases such as methane are some of the problems that need attention. Therefore, managing landfills by complying with strict regulations and applying gas and leachate processing technology is very important. In the future, continued efforts to reduce dependence on landfills and increase recycling, waste processing, and use of renewable energy are expected to reduce the negative impacts of final waste disposal.