What is the recommended practice for backfill after digging a trench?

Backfilling a trench with the spoil from the trench is considered best practice because it is efficient and cost-effective. This approach utilizes the soil that has already been excavated, minimizing waste and reducing material transport and disposal costs.

Moreover, using the original spoil can ensure that the surrounding soils match in consistency and compaction characteristics, which can help prevent future settling or shifting. However, it is essential to ensure that the spoil material is suitable for backfilling and does not contain harmful contaminants or debris that could affect the integrity of the fill.

While other methods, such as using concrete or purchasing new materials, may have specific applications, they can be more expensive and less environmentally friendly. Mixing dirt and concrete could also create a material that does not compact well, leading to issues with stability and settlement over time. Therefore, reusing the spoil from the trench is the most recommended practice.