What is the required bedding material for gravelless seepage and chamber systems?

The correct choice, which indicates that the required bedding material for gravelless seepage and chamber systems is the earth excavation that is free from large clods, emphasizes the importance of using native soil as bedding. This choice highlights the goal of maintaining proper functionality and drainage of the system. Native soil is generally well-graded and can provide adequate filtration and support for the installation itself, ensuring that water can flow effectively through the system.

Using earth excavation that is devoid of large clods helps prevent any obstruction that can hinder the seepage process. The absence of clods facilitates better percolation and minimizes the risk of pooling or backup within the system, which can lead to system failure.

Other options may suggest the use of materials that are either overly manufactured or that could complicate the design and function of the system. Utilizing sand or a gravel and sand mix could lead to issues in drainage effectiveness and structural support, while prefabricated polymer bedding, although innovative, may not align with the specifications required for gravelless systems, which are designed to utilize natural materials from the site for optimal performance.