37 Rental, installation and maintenance of cleaning machines, including high pressure washing and machines for cleaning sewers, containers and drill holes, slurry treating machines, all for the oil, gas and ecological industries; repair services for machines in the oil and gas industries, including solids control machines, production waste management machines, filtration and screening machines, and machines for completion services; construction and supervision of subcontractors; technical supervision of building and construction projects; rental of treatment, cleaning and purification machines for use in the oil, gas and ecological industries; rental of equipment and machines, all for use in liquids spill recovery, pressure washing and sump cleaning; rental of solids control machines, production waste management machines, filtration and screening machines, and machines for completion services, all for the oil and gas industries; installation, maintenance and repair services, all relating to the aforesaid equipment and machines; installation, maintenance and repair services, all relating to equipment and machines for use in fluids management, solid control, production waste management machines, filtration and screening machines, machines for completion services, machines which clean and purify environments and environmental clean-up, in the oil, gas and environmental industries sectors; installation, maintenance and repair services, all relating to equipment and machines for use in the separation of solids from liquids, liquids from solids and liquids from liquids, all through mechanically or chemically enhanced means in the oil and gas and environmental industries; installation, maintenance and repair services, all relating to equipment and machines for filtration, slurrification and liquid transfers; rental of tools, equipment and machines, all for use in oil and water well drilling