a political crisis. Dutch aid stopped to a large extent after Dési Bouterse was elected president. Aid from China has increased. Mineral industry Bauxite The backbone of Suriname's economy was the export of aluminium oxide (alumina) and small amounts of aluminium produced from bauxite mined in the country. In 1999, the aluminium smelter at Paranam was closed and mining at Onverdacht ceased; however, alumina exports accounted for 72% of Suriname's estimated export earnings of US$496.6 million in 2001. Suriname's bauxite deposits have been among the world's richest. Inexpensive power costs are Suriname's big advantage in the energy-intensive alumina and aluminium business. In the 1960s, the Aluminum Company of America (Alcoa) built the US$150-million Afobaka Dam for the production of hydroelectric energy. This created the Brokopondo Reservoir a 1,560 km2 lake, one of the largest artificial lakes in the world. West Suriname Plan In 1976–1977, a 100 km long single track railway was constructed by Morrison-Knudsen in West Suriname from the bauxite containing Bakhuis Mountains to the town of Apoera on the Courantyne River, to transport bauxite by river to processing plants elsewhere. The construction of this railway was financially funded by the Dutch government's independence/severance payments after November 25, 1975. After completion of this railway and associated facilities, for political and economical reasons it was never actually used and was left to be overgrown by the jungle. Also plans to construct a dam in the Kabalebo River were developed but never fully executed. In 1984, Suralco, a subsidiary of Alcoa, formed a joint venture with the (at that time) Royal Dutch Shell-owned Billiton Company, which did not process the bauxite it mined in Suriname. Under this agreement, both companies share risks and profits. The major mining sites at Moengo and Lelydorp are maturing, and it is now estimated that their reserves will be depleted by 2006. Other proven reserves exist in the east, west, and north of the country sufficient to last until 2045. However, distance and topography make their immediate development costly. In October 2002, Alcoa and BHP Billiton signed a letter of intent as the basis for new joint ventures between the two companies, in which Alcoa will take part for 55% in all bauxite mining activities in West Suriname. The government and the companies are looking into cost-effective ways to develop the new mines. The preeminence of bauxite and Alcoa's continued presence in Suriname is a key