The copper mine, one of the world's biggest, is on track to begin production in the first quarter of 2016, despite weak prices and relentless protests against the project.
The accident would have been avoided had the EPA team checked on water levels inside the abandoned mine before digging into its collapsed and leaking entrance, says document.
Australia's Clean TeQ Holdings Limited, a long-time industry leader in environmental remediation, has recently partnered with China's largest power generator to treat waste water with its unique continuous-ion technology.