2010 Copiapó mining accident San Jose Mine were around 20% higher than at other Chilean mines due to its poor safety record. The collapse occurred at 14:00 CLT on 5 August 2010. Access to the depths of the mine was by a long helical roadway. A group nearer the entrance escaped, but a second group of 33 men were trapped deep inside. A thick dust cloud caused by the rock fall blinded the miners for as much as six hours. Initially, the trapped miners tried to escape through ventilation shafts, but the ladders required by safety codes were missing. Luis Urzúa, the duty shift
2010 Copiapó mining accident means to find the men were sought. The accident happened soon after sharp criticism of the government's handling of the Chilean earthquake and tsunami. Chile's President, Sebastián Piñera, cut short an official trip and returned to Chile in order to visit the mine. Exploratory boreholes about in diameter were drilled in an attempt to find the miners. Out-of-date mine shaft maps complicated rescue efforts and several boreholes drifted off-target due to the extreme drilling depth and the extremely hard rock. On 19 August one of the probes reached a space where the miners were believed to be trapped but found