Massachusetts Construction Supervisor License (CSL) Practice Test

A drainage system is not required for a foundation of a single-family dwelling when it is installed on well-drained ground or sand-gravel mixture soils. This is because well-drained soils effectively manage surface water and groundwater, reducing the risk of water accumulation around the foundation. In such environments, the natural drainage capability minimizes the potential for excess moisture that could lead to foundation issues like hydrostatic pressure or erosion. In contrast, the other options suggest conditions where moisture management is still a concern. For example, while spread footings and damproofing can offer some protection, they do not eliminate the need for a drainage system in all scenarios. Waterproofing can significantly reduce moisture intrusion, but it is generally considered best practice to have a drainage system in place to ensure long-term protection against water-related problems. Therefore, option B correctly identifies a situation where a drainage system can be deemed unnecessary due to the favorable soil conditions.