Mine Environment Neutral Drainage

Feasby D. G., Blanchette M., and Tremblay G. (1991) The mine environment neutral drainage program. In 2nd Int. Conf Abatement of Acidic Drainage. MEND Secretariat, Tome, vol. 1, pp. 1-26. 

SENES Consultants Ltd., Acid Mine Drainage - Status of Chemical Treatment and Sludge Management Practices , Report prepared for the Canadian Mine Environment Neutral Program (MEND) and CANMET. Canadian Center of Mineral and Energy Technology, Ottawa, Canada, 1994. 

Pepin G., Bussiere B., Aubertin M., Benzaazoua M., Plante B., Laflamme D., Zagury G.J. 2008. Field experimental cells to evaluate the potential of contaminated neutral drainage generation at the Tio mine Quebec, Canada. Proceedings of the 1(fh IMWA Mine Water and the Environment, Czech Republic, 309-312. 

Table 13.10 gives some critical threshold values of NH3 in the environment. In-stream standards in many states allow a maximum concentration of 0.02 mg L-1 unionized ammonia in trout waters and 0.50 mg L 1 in all other waters. No limits are set in drinking water standards. Ammonia is often used to neutralize acid mine drainages (AMD) as well as other industrial acid- or metal-rich drainages (e.g., woodpulp and electronics). Many states have banned or discourage the use of ammonia for such purposes unless extensive monitoring is carried out. 

Euan, Z., et al. (1997). Neutralization and flocculation of acidic is mine drainage with alkaline wastewater. Zhongguo Huanjing Kexue/China Environ. Science. 17, 1, 87-92. 

In addition to dilution of acid rock/mine drainage under oxidizing conditions, neutralization can occur under mildly or highly anaerobic conditions. This will create distinctive environments in which microorganisms thrive and nanoparticles form as a result of their activity. We describe two examples of such subsurface systems below. However, before turning to these topics, we note that Fe-based microbial ecosystems are not only found in association with metal sulfide deposits, but may be broadly relevant in the subsurface where Fe-rich minerals (biotite, olivine, pyroxenes, etc.) are present in reasonable abundance and dissolve, releasing aqueous ferrous iron. 

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