Preliminary study and tender design for the underground Physics laboratory. The work in question is located on the border between Argentina and Chile. The idea of the Physics laboratory stems from the opportunity created by the construction of the Auga Negra road tunnel that crosses the border between Chile and Argentina (Lombardi project in 2013). Approximately in the center of the tunnel, with an overburden of about 3000 m, the CLAF (Centro Latino-Americano de Física) proposed the construction of a physics laboratory communicating with the tunnel (TAN). The laboratory has a total volume of 67'607 m³ and includes various rooms dedicated to physical experiments, clean rooms and biology laboratories. Water supply systems and water purification plants, treatment plants for waste water by bioreactors, compressed air, fire prevention systems and ventilation systems for air exchange, air conditioning as well as smoke and heat extraction systems have been planned. For the supply of water for human and fire-fighting purposes, shunts were created from the equipment of the road tunnel. The air for the air-conditioning, hygienic changes for the extraction of smoke and heat and heat exchange aimed at air-conditioning takes place with the external environment, through 6 km of hydronic and aeraulic pipes that pass inside the safety adit of the road tunnel.