HomeMining & EnvironmentWhat is MDAG?Publishing & DownloadsCase StudiesFractal 1/f SlopesLibraryLinksContact UsSearch


 

Minesite Drainage Assessment Group
www.MDAG.com
MINESITES, MINING, AND THE ENVIRONMENT





MDAG.com: Online Since 1997
Providing Valuable Technical Information on Minesite Drainage,
and on the Environmental Geochemistry of Highly Reactive Geologic Materials


Google
Internet www.MDAG.com



************************

The latest MDAG Case Study 82 is: The Meaning and Complexity of pH "Plateaus", like pH 3.0 to 3.7 for Fe-OH Minerals, during Neutralization along Flowpaths.

This MDAG Case Study is about pH plateaus (originally called geochemical “sub-regions”) during the neutralization of acid rock drainage (ARD) along flowpaths. This Case Study shows how recent documents like the INAP GARD Guide fail to identify the original source of these pH plateaus and fail to accurately describe the meaning and complexity of the plateaus. Tracing backwards through older documents confirms the original source of pH plateaus, which provides information on the true complexities and provides the detailed explanation, simulation, and application to full-scale ARD of these plateaus and sub-regions.



************************

MDAG Case Studies #80 and #81 are:
#81: The Complex Nexus of Sulphide Oxidation, Silicate-Mineral Dissolution, and Passive CO2 Capture
#80: Silicate Neutralization Potential Focussing on Plagioclase, and the MDAG Silicate NP Model
The spreadsheet-based MDAG Silicate NP Model (~150 kb, Version 2024.02) can be downloaded for free here.

There is a small percentage of minesites where Silicate NP (Neutralization Potential) is much more important than Carbonate NP for assessment and predictions of acid rock drainage (ARD). They are at the nexus of three interacting geochemical processes:
   (1) sulphide oxidation and acidity generation,
   (2) the rapid dissolution of neutralizing, calcium-bearing silicate minerals, particularly calcium-bearing plagioclase minerals, and
   (3) the passive capture of atmospheric CO2.
The relative importance of silicate NP can be signified by site characteristics like (1) typical acid-base accounting (ABA) predicts substantial ARD but none is detected, and (2) no ARD is detected on the full scale while smaller-scale kinetic testwork releases ARD within years. Based on past studies and one recent study, these MDAG Case Studies formulate an approach for more reliably assessing Slow-Neutralizing Silicate NP and Fast-Neutralizing Silicate NP with a focus on plagioclase minerals. Fast-Neutralizing NP is then combined with Carbonate NP to obtain the most relevant, effective Total NP. The intensity and types of testwork and studies needed to understand silicate neutralization on a site-specific basis, and the reasons for the failure of typical ABA, are highlighted.

Note: These Case Studies provide supporting information for a paper published by and presented at ICARD 2024, entitled "Predictions of ARD Potential Dominated by Silicate Neutralization Potential at the Troilus Gold-Copper Minesite, Québec, Canada".  A draft version of this paper with additional figures and tables not in the final version is available here. An expanded version of the PowerPoint presentation with additional figures, tables, and explanations not in the final version is available here. Additional presentations and explanations can be found here and here, including the presentation at the BC MEND 2024 31st Annual Workshop.


************************

Five technical books on minesite drainage and highly reactive geologic materials are available here at MDAG.com, free of charge.

1) Wavelet Transforms of Drainage from Highly Reactive Geologic Materials; ISBN 978-0-9952149-3-4

2) Searching for Latent Variables in Minesite Drainage Using Exploratory Factor Analysis; ISBN 978-0-9952149-2-7

3) Spectral Analysis of Drainage from Highly Reactive Geologic Materials; ISBN 978-0-9952149-1-0

4) Environmental Geochemistry of Minesite Drainage: Practical Theory and Case Studies; ISBN 0-9682039-1-4

5) Minesite Drainage Chemistry: An Introduction; ISBN 978-0-9952149-0-3


************************

We have also published and co-published more than 100 informative documents at conferences and in journals.
 

************************

Adverse environmental effects can arise from water draining over and through highly reactive materials, such as mining wastes. We steadfastly believe that these adverse effects can only be understood, predicted, moderated, and remediated reliably by thoroughly understanding past competent work and by carefully studying full-scale sites.

Heed the old words of wisdom "Those who ignore the past are doomed to repeat it" or perhaps some newer ones "we learn from the mistakes of the past how to make new ones". Is that why we hear that up to 90% of predictions of minesite-drainage chemistry are too low, and remain too low for newer minesites, leading to unexpected costs and adverse environmental effects for mining companies and taxpayers?  The public is starting to pay closer attention to these errors and unexpected costs, with mining companies losing credibility.  This is why we at MDAG heavily emphasize real case studies with abundant data, followed by theory and modelling in subordinate roles.

 

Privacy Policy: We don't know who you are and we do not try to find out. Enjoy the site!

Google
Internet www.MDAG.com

The ML-ARD Song


HomeMining & EnvironmentWhat is MDAG?Publishing & DownloadsCase StudiesFractal 1/f SlopesLibraryLinksContact UsSearch


Created by K. Morin