Underground Earthing

It is easy. Try to drill deep to ground (same to drilling ground water) until you have 0.5 Ω risitance.

Good luck.

Please try long copper-rods and conductive gels/bentonite.

if it is mat (grid), you should get it, its not big deal, some method you can try from IS3043, if working in India.

Hello : Normally, as others have suggested, the deeper you go the lower the overall ground resistance; however, sometimes the soil in question has two or three distinct resistivity layers ( therefore not homogeous!) and sometimes going deeper gets you into higher resistivity !! You must measure the soil extensively enough to confirm the overall resistivity first. Secondly, don't forget that the resistance is inversely proportional to the area of your ground grid and the area surrounded by your perimeter ground conductor loop. So, you may have to go to a much larger area, say 10,000 sq. meters or more ; it all depends on several variables -- I fault, soil resistivity, ground grid, area, time ( .5sec or more), any neutrals or ground wires coming into your substation with the phase conductors.

You need to define your soil model (uniform or multi-layer model). The underground water level, is it fixed or varying). The grid size, the number, location and length of grounding electrodes to be added to the grid. All the details ate available at IEEE Guide for safety in AC Substation grounding, IEEE std. 80-1986, IEEE tutorial course, 86 EH0253-5-PWR, and IEEE guide for measuring earth resistively, grounding impedance, ANSI/IEEE std 81-1983.

Regards

AMSG