North Carolina General Contractors Practice Exam

How does backfilling become impossible due to groundwater?

1. It solidifies the soil

2. It creates liquid mud

3. It makes soil erosion easier

4. It increases soil density

The correct answer is: It creates liquid mud

Backfilling can become impossible due to groundwater because the presence of excess water causes the soil to turn into liquid mud. When groundwater levels rise and saturate the soil, it loses its cohesion and stability, making it difficult to maintain the structural integrity needed for effective backfilling. This condition can prevent workers from compacting the fill material properly, leading to improper site conditions that could affect the overall project. By transforming the soil into a mud-like state, heavy machinery or additional fill materials may become ineffective or unmanageable. Thus, ensuring proper drainage and controlling groundwater levels are crucial steps in preparing a site for construction activities, especially when backfilling is involved.