Dewatering: Thickening, Filtering, CCD, Water Treatment & Tailings Disposal

Dewatering: Thickening, Filtering, CCD, Water Treatment & Tailings Disposal

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AMD and Mine Permitting (25 replies)

S
Standartenfurer
8 years ago
Standartenfurer 8 years ago

Is anyone aware of a mine that has not been allowed to start operations because of potential AMD issues? Could the Pebble mine in Alaska be an example of such a mine?

Hauptsturm
8 years ago
Hauptsturm 8 years ago

The Pebble Limited Partnership did not submit any permit applications after baseline studies were completed. In the interim (between baseline work and permit applications) the EPA provided limits on the miles of streams and acres of wetlands associated with anadromous streams that they would allow to be impacted. These limits could restrict the size of the mine. But there have been no decisions that would allow or stop the mine project, since no permit applications have been submitted.

(unknown)
8 years ago
(unknown) 8 years ago

The permitting process for coal mines includes an assessment of AMD potential. In Pennsylvania, that is assessed through overburden testing and geochemical analyses (acid base accounting). If there is the potential for AMD production, the application must include an abatement plan. Usually this is alkaline addition sufficient to neutralize the acid producing potential of the overburden. If this plan is considered inadequate by the reviewers, the permit is denied. There are many examples of permits that were denied because of inadequately mitigated AMD potential.

I don't know of any cases where mining was blocked after a permit was granted. But I don't track such things.

Hauptsturm
8 years ago
Hauptsturm 8 years ago

Can you provide the names of or some details about some proposed projects where permits were denied?

(unknown)
8 years ago
(unknown) 8 years ago

The only mine I know about was a long time ago (in BC). It was called the Windy Craggy project, I believe. There was concern that it would affect the Windy Craggy River.

Victor Bergman
8 years ago
Victor Bergman 8 years ago

Two proposed mine projects have recently run into permitting hurdles that have significantly delayed their permitting schedule. Both are a result of misconstrued information about potential impacts to local water quality. Taseko Mines New Prosperity Project in B. C., Canada and Tintina Resources Black Butte Project in Montana, U.S.

Refer to the respective companies web sites for more information.

O
OberstGruppen
8 years ago
OberstGruppen 8 years ago

From the examples above, it seems that permitting denial due to potential AMD concerns is limited to countries that can afford it?

(unknown)
8 years ago
(unknown) 8 years ago

It appears to be related to the regulations of the jurisdiction which vary even across Canada.

Jean Rasczak
8 years ago
Jean Rasczak 8 years ago

You could look at Redbank Copper Mine in the Northern Territory, Australia. Legacy issues with about 60kms of creek affected by AMD. Other companies have looked at reopening the mine but have these issues to address. To add to this, the issues also cross two states.

S
Sturmbann
8 years ago
Sturmbann 8 years ago

Crown Jewel in Washington went through the EIS process as a prospective open pit gold mine in the late 1990s and then failed to be permitted (I don't know the 'official' reason but think that water quality was a core concern). Ultimately, an alternative project (smaller underground mine) was permitted and developed. I think the ownership changed after the failed permitting.

(unknown)
8 years ago
(unknown) 8 years ago

Well, any mining activity may cause AMD issue. However, AMD issue is as deadly as radioactive leaking. AMD problem could be contained if well-planning, monitoring and reasonable procedure is conducted. People is clouded by fear but not thinking about solution. If AMD can stop mining industry, deforestation may stop timber industry. Let's go back to Stone Age.

Bob Mathias
8 years ago
Bob Mathias 8 years ago

I agree with the consensus that potential to form acid rock drainage (ARD) needs to be adequately addressed to the satisfaction of the jurisdiction to grant an operating permit or to continue operations, if it does form. Bonding may be required. Not all mining can have ARD formation; it depends on the location and mineralogy.

S
Standartenfurer
8 years ago
Standartenfurer 8 years ago

As you aware we now have irrefutable proof that we can now eliminate the need for tailing ponds or earthen dams and profitably.

(unknown)
8 years ago
(unknown) 8 years ago

Windy Craggy is an interesting case. The very high (average 35%) sulphide levels in the ore meant that ARD production was certain. The proximity of the deposit to pristine wilderness was also a factor going against the mine. However, I recall hearing from a colleague that the high sulphide content presented intractable metallurgical problems, so the ARD issue may not have been the primary reason why the project was abandoned.

A number of coal project in BC (e.g., Roman Project) are predicted to release selenium in mine water, rather than produce ARD. Their permits are being denied until they can satisfy regulators that selenium can be removed from mine drainage.

Next to this, I think that sulphate levels in mine drainage will be the next challenge that makes it difficult for mines to be permitted.

(unknown)
8 years ago
(unknown) 8 years ago

Yes sulfate is already a major issue in MN, USA, where a standard of 10 mg/l in surface waters (intended to be protective of wild rice) has been a major permitting hurdle in recent projects.

Bob Mathias
8 years ago
Bob Mathias 8 years ago
(unknown)
8 years ago
(unknown) 8 years ago

It makes a serious point that deserves of consideration and analysis. As far as I can tell from forty years of involvement with mining, decision-making (by *all* parties, not just regulators) is a multi-component problem. AMD - it’s potential and means of control/mitigation - may be part of that multi-component problem in some deposits. But it is not the only matter involved, and we should not expect that it would be. The process of mine planning from the Proponent's viewpoint, as well as from the rest of the stakeholders, needs to accurately evaluate the AMD risk (consequence*probability, with and without mitigation) so that the costs can be fully understood and full balanced with the benefits. But a priori judgments that AMD ought to be the controlling factor seem to me naïve and potentially wrongly directed.

Consider, for example, the Ok Tedi Mine in PNG: it produces (and has for decades) about 20-25% of the GDP of the entire country. OTML have established medical clinics all along the drainage and have a fine record for managing malaria and a very modern HIV education and management plan. They have built schools and sponsored students through graduate studies; they have helped villages establish sustainable economic projects that will support the people of Western Province for generations after the mine closes. Its taxes and royalties are protected from corruption through a fascinating and very advanced model of investment, while still providing regular finds that are available to the country as a whole. Yes, there have been adverse impacts from mining, including AMD. But Ok Tedi provides a serious case study of how stakeholders working together in a developing-world setting can advance multi-component views of benefit to society and the environment without rejecting mining out of hand. Was the PNG decision-making to continue mining "correct?" Gee, what gives me, sitting in great comfort in USA, any standing to judge that?

On the other hand, one can look at the debacle at the Faro Mining Complex in the Yukon Territory (Canada) to see the potential risks even to rich countries (at least to their tax payers) when mining is poorly posed, executed, and regulated. From which I draw the conclusion that those of us in the rich countries need to be a bit careful about how smart we are about our own works.

(unknown)
8 years ago
(unknown) 8 years ago

Yes, Pebble is an example.

S
Standartenfurer
8 years ago
Standartenfurer 8 years ago

We now have irrefutable proof that we can create potassium nitrate, ammonium sulfate and sodium chloride from most AMD. We also have irrefutable proof that we can eliminate the need for tailings or earthen dams. Does anyone know of a mine that could benefit from such a process?

(unknown)
8 years ago
(unknown) 8 years ago

Your company is not different from others that provided irrefutable proof that they can treat ARD and forever solve this problem. This and previous claims will be greeted here with a mix of interest and scepticism.

We're interested in the potential solution that your technology presents and would like to hear more details. However, we also worry because of the rich history of similar fantastic claims that never panned out. From where I stand, you do not sound any different from others who made similar claims before.

Paul Morrow
8 years ago
Paul Morrow 8 years ago

In spite of its relative small size, the Kutcho property in north-western BC has been studied for its ML-ARD potential since the 1990s.

S
Standartenfurer
8 years ago
Standartenfurer 8 years ago

Should you like to visit our plant that is currently and consistently converting AMD into potassium nitrate, ammonium sulfate and sodium chloride I will gladly meet you onsite.

I understand your concerns that there are many claims out there with few results. This is why I challenge all who doubt our claims to investigate our process and visit our facility. As they say the proof of the podding is in the eating.

(unknown)
8 years ago
(unknown) 8 years ago

Show me a mine where your process has worked and for how long. Show me the feed chemistry and effluent quality; show me how reliably your system performed for fluctuating flows and feed composition. Show me your reagent costs and how these were offset by valuable by-products that were recovered. Convince me that your process will perform in Pittsburgh as well as in Faro, i.e., that you are not dependent on proximity to supply centers/buyers.

You claim to have irrefutable proof? Show it to all of us and let us be the judges.

S
Standartenfurer
8 years ago
Standartenfurer 8 years ago

You have a deal. Once the above has been achieved I will contact you again. It's important to note that I am not claiming to have the solution to every mine that has an AMD problem, for the very reasons you state in you last reply. I have data for you, and like I have said in past correspondence, we have a working facility treating AMD from a titanium dioxide mine that will demonstrate reagent cost and fertilizer production claims. Regarding irrefutable proof that we are producing fertilizers from AMD, what more proof do you need than physical proof? You can go yourself and sample the effluent water, produced water and fertilizers first hand. Product in hand is physical proof of our claim of fertilizer production from AMD. Never have I claimed that every mine no matter what the dynamics will be profitable. Flow rates such as the Berkeley pit and the Old Forge borehole are what we are looking for. These types of locations as per your concern above are in proximity to center/buyers and have a constant flow rate and will have for many years to come. I look forward to sending you scientific data for your opinion. I welcome your input and appreciate your time.

(unknown)
8 years ago
(unknown) 8 years ago

Your best bet is to make your case at an international conference like the IMWA or ICARD, where papers are peer-reviewed. Ideally, you will differentiate your process from others like the Australian hydrotalcite process or the South African ABC/MBO processes; or discarded ones like the Keeco or EcoBond processes. Most importantly, you need to convince everyone that switching from tried-and-true lime treatment is the best thing they can do.

I don't want to discourage you, but I have spent 25 years promoting wetlands for treating metal mine drainage and can honestly say that it is only recently that this concept has gained traction. This field is not one for the impatient.

S
Standartenfurer
8 years ago
Standartenfurer 8 years ago

Our paper was also peer reviewed at the National Ground Water Conference 2013. I do believe in Wetlands as a means of treating AMD. As you state, patience is a virtue when choosing wetlands as an option. Have you read our abstract? The Australian hydrotalcite process or the South African ABC/MBO processes is as far removed from our process as one can get. We create fertilizers from the anions and cations present in AMD and brackish groundwater.

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