Cable trench designed to be constructed beneath the live LV and HV cables; isolating the cables supplying power to KGP was not feasible . PTW controls, method statement, JHSEP, TRIC are inadequate in terms of specifying the right methodology, tools, safeguard required for this scenario (removing hard strata from beneath the live cables) without isolation. Permit Applicant ignored the risk involved in breaking the hard strata beneath the live cables and assigned the activity to Permit Holder without adequate briefing. Crew tasked with soil removal beside and underneath the exposed cables, encountered hard strata as there was no soft soil spread beneath the cables. Permit Holder did not consider stopping the work and seeking, instead chose to break the hard strata using pickaxe when the soil could not be removed using non-metallic shovel.