Earthing on a black bag landfill

[Prospero]

A client wants to build a new works on a disused landfill. There will be a number of 11/0.415KV substations on site.

FYI - there will be a 1-2m aggregate capping layer and hardstanding.

Does anyone have any experience of how to approach the earthing in such a situation?

 

[bacon4life]

With everything sitting on a big insulating plastic layer, seems like it will be bonding rather than grounding. Be sure to include plenty of mechanical flexibility to allow for significant settlement as the garbage decomposes.