Massachusetts Plumbers Journeyman Practice Exam

When backfilling trenches, how deep should the crown of the pipe be covered at a minimum before continuing?

1. Half a foot

2. One foot

3. Two feet

4. Three feet

The correct answer is: Two feet

The correct answer indicates that the crown of the pipe should be covered by a minimum of two feet of material when backfilling trenches. This depth is necessary to ensure proper support for the pipe and to prevent any potential damage due to surface loads. It provides adequate protection against external forces such as traffic or equipment that may pass over the area. In construction practices, covering the pipe sufficiently minimizes the risk of shifting or settling that could occur if the pipe is not adequately supported. A minimum of two feet also helps maintain proper drainage and reduces the likelihood of soil erosion or water infiltration, which can compromise the integrity of the pipe over time. For options that suggest shallower depths, while they may seem practical in certain situations, they do not provide the necessary structural support or protection required for the longevity of the plumbing infrastructure.