I dont live in your region, but have recently had my Fosse destroyed by the local Oil delivery merchant. Fortunately, the Insurance company that insured my Oil delivery company, paid in full. Surely EDF have a similar liability. My advice would be to contact a local Notaire, and ask if you could commence an Insurance action against EDF, assuming that you have a witness or admission from EDF that they did do what you say they did. Hope this helps. Mike