Special operations on soil, including device of foundation, special construction and installation works of spacer of linear constructions including major repair and reconstruction of trunk power lines with tension to 35 kV and up to 110 kV and above; trade and backbone networks of oil pipelines, gas pipe line also backbone networks of oil pipelines; steel tanks (capacities) working under pressure or intended for storage of fire and explosions or other dangerous (harmful) liquid or gaseous substances.