Current best practice for decommissioning oil filled lead sheathed cables is to remove as much oil from the cable as possible and then leave the cables in the ground or alternatively excavate the cable route to extract the cable (although this is costly). The proposal is to pump biological agents into the out of service cable that would degrade the oil impregnated insulation sufficiently to allow the cable core to be extracted from the cable at joint positions. This would reduce the environmental risk of the cable system, allow recovery of valuable materials reducing waste and allow recovery of the cost of the material (generally copper) and leave a conduit for future use.

Objectives

Development of a technique to remove the core of an oil filled cable while the cable is still buried in the ground. This will allow the copper conductor to be recovered and leave an unfilled duct that can be re-used.