On Aug. 4, 2014, the massive dam storing tailings from the gold and copper mine gave way, spilling 24 million cubic metres of mine waste and water into nearby lakes and rivers.
The phase one cleanup was meant to stabilize a creek and ensure water quality.
Environment Minister Mary Polak said Wednesday the results from this first phase are promising.
"One of the key outcomes was ensuring the water quality in Quesnel Lake met provincial water quality guidelines," she said.
"And so I'm pleased to note that it continues to be safe for drinking, for fishing and for recreational use."
Nevertheless, she said there is a still a lot of work to do, and that phase two of the cleanup is expected to continue through the summer of 2016.