I’m sure there are better methods, but in the Cotswolds, I resorted to a 1m long drill drill to put a hole through any stones in the compacted farmed layer. It was then possible to drive rods through the holes, presumably splitting the stones on the way. Once through this layer, it was possible to continue driving the rest of the 1.5m rod in. After a season the soil movement locks the rod in immoveably. Ground resistance per rod was around 80 ohms, so a lot of rods were needed to provide an acceptable lightning ground.
Alwyn Seeds, Director
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