The Agua Negra Crossing (4750 masl) is a high mountain pass between Argentina and Chile, connecting San Jose de Jachal (San Juan Province, Argentina) with La Serena on the Chilean Coast, and its port, the City of Coquimbo. At present, the more than 200 km-long pass road has a gravel surface. In summer, daily maintenance of the road surface is carried out, particularly along the winding narrow sections close to the border where steep gradients exist and which are not drivable for heavy goods vehicles.Nevertheless the pass road is frequently used by both cars and small busses during summer and holiday times on long weekends.
The Chilean Government and the State Government of San Juan are now planning to upgrade this transit route over the Andes by constructing a road tunnel. Doing this would create an all-season, alternative heavy-transport transit route between Chile and Argentina, which runs through Mendoza and the Túnel Cristo Redentor. The current route through Mendoza and the Túnel Cristo Redentor is many times impassable several days during winter due to heavy snowfalls.
GC GROUP commissioned with a partner company to carry out the geological, hydrogeological and geotechnical mapping, at altitudes of 3500 to 6000 masl, for two tunnel variants. By now, the prognosis for both tunnel variants and the future site investigation program have been developed.