The Casino mine proposal still has a long way to go before it will be fit to enter the territory’s environmental review process, assessors announced this week.
“The executive committee has determined that the supplementary information provided by the proponent is still lacking important information and that the proposal remains inadequate for screening,” according to a news release from the Yukon Environmental and Socio-economic Assessment Board.
The proposal originally submitted by Casino Mining Corporation to the board ran more than 7,000 pages over 13 volumes. It is by far the most significant project ever planned in the Yukon.
The $2.5 billion open-pit copper gold mine, if built, is expected to process 120,000 tonnes per day over a 22-year mine life. That’s 30 times the processing rate at Capstone’s Minto mine.
The proposed tailings dam is expected to be 286 metres tall and 2.5 kilometres long, among the very tallest dams in the world.
The Casino tailings facility is expected to hold back 956 million tonnes of tailings and 658 million tonnes of waste rock after the mine’s closure, and forever into the future.
That dam is a key area of concern for the assessment board.
“One of the most significant aspects of the project is the tailings management facility and dam and the risks associated with its scale, northern context and its requirement to remain stable in perpetuity,” according to the release.
The board has hired dam expert Norbert Morgenstern, who also leads the Mount Polley Review panel, to help assess the viability of Casino Mining’s proposal.
It has also hired six other individuals and consulting firms with expertise in other parts of the project.
Casino’s original proposal was submitted to the board in January, 2014.
The assessment was suspended by agreement for about six months after affected First Nations insisted they needed to be further consulted before the review be allowed to proceed.
In January of this year the board provided the company with a long list of questions it needed to answer before the proposal would be considered adequate.
Casino Mining responded in March, but much of the information was incomplete, according to the board.
“The proponent has sufficiently answered about half of the questions presented in our adequacy review report but there is still more work to be done before the screening can begin,” executive committee member Ken McKinnon said in the release.
The key areas where more information is needed are the tailings facility and dam, the closure and reclamation plan, the access road to the mine, and the traditional land uses by First Nations in the area.
The board has recommended that the company establish an independent geotechnical review panel to help deal with some of the outstanding questions.
After that information is provided to the satisfaction of the board, the assessment of the actual contents of the proposal will begin.
The company still plans to have the project assessed and permitted by the end of next year. This is highly unlikely, given the magnitude of the project and how long it has lingered in the earliest stage of assessment.
The company must also secure financing for the project if it is to be built.
Financing talks will get more serious once the mine is further along in the assessment process, company president Paul West-Sells told the News last year.
Contact Jacqueline Ronson at