Which of the following indicates that you are excavating near an underground service?

The presence of unusual materials like crushed blue metal or plastic tape is a strong indicator that you are excavating near an underground service. These materials are often used to mark the location of buried utilities such as gas, water, electrical, or telecommunications services. The appearance of these items can signal that utility lines are nearby, thereby highlighting the need for caution and further investigation before continuing excavation work.

Having a visual reference, such as colored tape or markers, helps workers recognize that they are encroaching on areas that may contain hazardous or essential utility pipes and lines, thus reinforcing the importance of checking for underground services prior to excavation.