What must utility companies be informed about before starting excavation?

Utility companies must be informed about the proposed work and requests to locate utilities before starting excavation because this ensures the safety and integrity of existing utility lines. Properly locating utilities is crucial as it helps prevent accidents that could occur if an excavation inadvertently damages underground cables, pipes, or other utilities. It also allows utility companies to provide important information, such as the type of utilities present and their exact locations, which is vital for planning and executing the excavation safely.

The other choices, while relevant to general project planning, do not specifically address the immediate concern of utility safety during an excavation. Knowing the estimated project timelines and plans for waste disposal are important for logistics, while understanding excavation depth and width relates to the excavation itself rather than the necessary precautions regarding existing utility infrastructure.