What is the correct procedure to follow when a high loop impedance reading is measured at the meter box.

In the past I have contacted the faults number and notified the council ... however nothing was done and still nothing has been done.

I have another site which is recording a high loop impedance reading with the earth disconnected from the electrical installation ... it has a lead cable supply from the road.

I have considered knocking a spike into the ground as an additional safety measure until it is sorted out.

How do you tackle high loop impedance readings on a site?

What range would you classify the risk low - medium or high ?