Rhode Island Journeyman Plumber Practice Exam

Backfilling shall be placed in layers free from rocks, broken concrete and frozen chunks in which manner?

1. In single layer

2. In three layers

3. In two layers

4. In four layers

The correct answer is: In three layers

When backfilling, it is essential to place the material in layers to ensure proper compaction and stability. Placing backfill in three layers allows for better control over the compaction process, ensuring that each layer is adequately packed down before the next layer is added. This practice minimizes the risk of settling or shifting after the fill has been completed. The use of multiple layers helps to achieve even distribution of the backfill material and prevents large voids that could lead to complications in the future. Each layer can be thoroughly compacted, making sure that any rocks, broken concrete, or frozen chunks are effectively avoided, as per the requirements for proper backfilling. Splitting the fill into three layers is a balanced approach, effectively facilitating the mechanical compaction methods commonly employed in plumbing and construction. In contrast, placing backfill in a single layer may lead to insufficient compaction and potential settling issues down the line. Similarly, using too few or too many layers might not provide the optimal balance for effective compaction, which is why three layers is considered the best practice. This method ensures the integrity of the backfill against future loads and disturbances.