the country s largest mining companies including stateowned codelco the world s largest single producer of copper apply internationally certified systems or their own systems of corporate environmental management large mining companies have engaged in voluntary clean production agreements acuerdos de produccion limpia apls which cover mine closure efficient use of energy and water sewage and waste management and acid water drainage particulate emissions need to be further reduced and water use efficiency increased in the sector mining competes with agriculture and human consumption for increasingly scarce water resources many abandoned tailing dams in chile are in deficientunsatisfactory condition and much mining wastewater from large companies remains untreated