Generally, power cable tunnel is installed beneath roads, therefore possible tunnel routes are determined as the combination of roads that connect start and end terminal substations.

The purpose of the task is to select the most suitable tunnel route and shaft location from possible options based on existing materials and results of site survey.

TEPCO has vast experience in the selection of tunnel routes and shaft locations, and has skills and knowledge about transportation legalities. Therefore it is possible for us to select the most effective and reasonable tunnel route and shaft location for power cable. Details of selection of tunnel route and shaft location are as follows.

• Options of possible tunnel route and shaft location
  • We look at several options of possible tunnel route, considering road conditions, surrounding conditions, existing objects, ground conditions and construction method of the tunnel.
  • We make several options of possible shaft location considering length of tunnel span, lands for shaft construction and length of ventilation facilities span.

• Selection of tunnel route and shaft location
  We select the most suitable tunnel route and shaft location form the available options. Items for selection standards are as follows.
  
  Tunnel Route and Shaft Location
  • Estimated total cost (included land cost, if necessary)
  • Construction Period (included necessary official procedure)
  • Impact on environmental issuers to outside
  • Possibility of acquiring land permission
  • Reliability of construction method