Boring and building of waterwells, driving of wells
Building of conveyance, distribution and water disposal networks
Terracing work: digging, grading of construction sites, opening of trenches, removal of rocks, destruction with explosives, etc.
Ground-water lowering and dredging of construction sites
Installation in buildings or in other projects of building of: pumbling systems and hygiene appliances, pipes for gas and water (except for heating), setting of automatic extinguishers, etc.