What kind of materials can be used for separation in a gravel system?

In a gravel system, the use of newspaper or untreated building paper can be beneficial for separation purposes. These materials serve as a filter to help prevent finer particles from clogging the gravel layer, allowing for effective drainage and maintaining the system's function. They are also biodegradable and will decompose over time, which aligns with the principles of sustainable septic system practices.

The use of synthetic fabrics, although sometimes utilized in other applications, may not provide the same level of natural filtration and could contribute to long-term waste accumulation in the system. Concrete or metallic materials generally do not serve a separation function in gravel systems and could lead to problematic outcomes by hindering the flow of water. Similarly, while biodegradable plastics may have specific uses, they may not effectively fulfill the separation roles expected in a gravel system due to their differing decomposition and durability characteristics compared to organic materials like paper.