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Archive for the ‘consulting’ Category

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Here is a challenge written up in a recent comment on a previous blog posting:

I would love to see someone write a paper on the merits of a wet tailings pond. Today’s lovechild seems to be the filtered tailing concept but let’s hear some kudos for a properly designed wet tailings pond. It gives the ability to deal with seasonal or short term storm water surges, the ability to store water for use in low flow periods, avoids needing to continually withdraw process water from rivers or lakes, keeps ARD materials submerged, lower capex & opex, lower power consumption via natural clarification instead of mechanical clarification, and less greenhouse gas emissions related to lower power consumption. Where are the friends of the conventional tailings pond or have they gone into hiding from the filtered tailings mob?

Today I had lunch with John Gadsby who is 82 and still active in tailings.  Way back in 1983, he and Syd Hillis were the peer reviewers of my work on the design and construction of the Cannon Mine tailings facility besides Wenatchee, Washington.  I asked him the questions implicit in the comment above.

He quickly reminded me that the Cannon tailings facility was a very successful wet tailings deposition facility that was also designed to contain lots of water from heavy rains in the catchment area of the Cascades.  He reminded me that that facility was built to be secure as it is upgradient of a significant part of Wenatchee.  He said he thought the facility must surely represent the best tailings technology for wet tailings deposition ever.  And now it is closed and part of the Dry Gulch Riding Stables–an asset to the local community.

Without being too bold & boastful, I know this dam was good, is good, and will remain stable for a very long time hence.  It proves, in my mind, that you can mine close to communities, can safely manage wet tailings in sensitive environments, and can close mine sites for sustainable use.  Here are links to some papers I wrote on its design & construction:

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You can get all these papers by going to the InfoMine Library and doing a search for Cannon Caldwell.  You can also get a lot more information at the official Cannon Mine website.

So now let us have a debate about whether this tailings facility built in 1983 and 1984 represent current best practice or best available technology for wet tailings management.  I think it does, but then I am hopelessly prejudiced.  And I recognize parochial sentiments sometime inhibit cross-boarder admiration of engineering works.  Still you can get there in a four-hour drive from Vancouver.  Go see it sometime.

 

 

 

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Goldcorp has announced that it will seek to involve more women in mining.  That is admirable.  Here are some of my stories of women in mining. (more…)

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As a US taxpayer I am at loss to understand how $1 million dollars can be sent to Peru to deal with illegal mining.  Here is a link to one report on the US taxpayer-funded largesse.  The report notes:

The U.S. Department of State awarded US$1 million to the Blacksmith Institute to work with Peru’s Ministry of Environment (Minam) to reduce the use of mercury and design remediation plans in Madre de Dios and Puno, it was announced today.

The United States believes it is crucial to support the Peruvian government strategy to combat illegal mining and reduce mercury use in artisanal and small-scale gold mining.

Where is the Tea Party when we need them?   Have they nothing to say about this blatant waste of money to support a lousy government unable to manage it own affairs?  The only explanation I can come up with is that somebody related to somebody or indebted to somebody has managed to arrange this and is being paid a considerable percentage of the funds.  Smells rank & corrupt to me. (more…)

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The Mining Association of Canada (MAC) has announced that they are convening a panel to ” review its tailings management requirements to ensure failures, such as the one registered at Imperial Metals’ Mount Polley open pit copper and gold mine, can be prevented.” (more…)

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In an upcoming EduMine course on Risk Assessment, Decision Making, and the Management of Mine Geowaste, we write the following on the topic of Net Present Value (NPV): (more…)

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Here is a comment posted on a recent blog item:

Jack,

I have been following your blog since the Mt Polley incident.

I am not sure if you have seen the design yet for the proposed copper project located in the Thompson River Watershed near Vavenby. Here is the link to the Knight Piesold report Appendix 3E. http://a100.gov.bc.ca/appsdata/epic/html/deploy/epic_document_333_38590.html

You will have to click on Appendix 3-E to download the PDF.

It looks like they are submerging PAG which results in a huge amount of water storage ( see attached document which shows the supernatant pond volume increasing every year; similar to Mt Polley). Let us hope they have their water quality model correct otherwise it will be a large treatment plant at the end of the life of mine.

Thought you might be interested in seeing what the BC regulators are being presented with even after the Mt Polley disaster. Will industry change to a more conservative approach to tailings designs?

Enjoy your musings.

I went to the site recommended and downloaded the Executive Summary, the section on Geochemistry, and the section on Closure.  Fascinating writings, particularly coming post-Mt Polley.  I hope some readers of this blog take a look at the report and comment.  For this is a public posting of design documents–worthy of repetition.  Now it remains to be seen if such public posting leads to public reading and comment.  For that, afterall, is the purpose of such public posting of designs for new mines and their tailings facilities.

I note that the closure cost estimate is some $16 M.  Presumably that is the basis of the bond being posted?  Comments on its sufficiency would be of interest.  As would comments on the way they plan to deal with acid generating tailings. As would comments on the above comment/question as to whether this is a more conservative design than Mt Polley.

I have not read in sufficient detail to comment with insight.  And maybe no other BC engineer has any more time or inclination than I have to comment.  That is a pity, but inevitable.  Is this a pointed reminder that in addition to such public postings, maybe we should have public posting of the comments by an Independent Tailings Review Board as Morgenstern recommends in the Mt Polley report?  Again your perspective would be welcome.

If you find the materials at the listed site formidable, rather go to the company’s website at this link.   It seems not to have been updated since 2013.  So the BC regulators are faster and more  up-to-date in their posting.

In the current mining downturn, these numbers are impressive:

The project is expected to employ up to 430 hourly and staff personnel. Based on industry experience, approximately 1,000 to 1,200 jobs will be created in the surrounding communities and elsewhere within the province to provide support to the project.

No wonder the BC government is doing all it can to get the word out about the project.

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I get many pleas for help in finding a job in mining.  Most I refer to Careermine.  For that is the site that lists every possible job in mining.  Yet this one caught my attention, for it is a story of love.  At least I think so.  I have the sender’s permission to post what she sent me.  Here it is. (more…)

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