What key information must be included on a tower map regarding the location of underground utilities?

A tower map must include precise information regarding the location of underground utilities to prevent accidental damage during excavation or construction activities. This includes the horizontal location of all underground utilities, such as electrical cables, gas pipelines, water lines, and communication conduits, marked with their respective utility type. The depth of each utility should also be indicated, where available. The map should also include the utility owner's contact information in case of emergencies or for obtaining further details about the utility. Furthermore, the map should show the 'tolerance zone' around each utility, which is a designated area where extra caution is required during excavation to avoid damaging the utility. It is important to note the source of the utility information (e.g., utility company records, site surveys) and the date the map was created or last updated. This information is critical for ensuring worker safety and preventing service disruptions.