ARCADIS is the industry leader in developing and fielding mine waste treatment technologies. Our patented bioremediation technology allows for in-situ treatment of a wide variety of constituents typically present in mining materials, including ammonia, cyanide, nitrate, and sulfate, as well as many metals. By performing treatment within the mine materials, more extensive cap and cover systems, and their related costs, can be avoided.
In-situ reactive walls and reactive zones (IRZ) are used to remediate groundwater beneath tailings impoundments, leaking leach pads or ponds at mines or smelters, or downgradient of pit lakes. Use of this technology can avoid extensive treatment of source areas, and replaces costly and inefficient pump and treat systems.
In-situ treatment is also used to avoid a hazardous waste classification by successfully reclassifying wastes. Our unique understanding of these processes allows us to design in-situ treatment to an appropriate level, and design and implement systems that provide for enhanced bio-attenuation for permanent closure.
ARCADIS' patented technologies have applications in pit lakes, smelter ponds, and flooded mines and underground workings where the water quality would otherwise require pumping and treating the water ex-situ. In-situ treatment also can be used to avoid backfilling pits with waste and overburden materials, reducing the cost of closure by reducing the volume of earth materials moved at closure. We have also applied a patented variation of this technology to reduce groundwater impacts and management costs from backfilled pits.
Our approach to acid rock drainage (ARD) avoids the typical approach of effluent-collection and treatment that drives the perception of perpetually required operations and maintenance. Our patented technology actually prevents the ARD process from occurring. By creating reducing conditions within the waste rock or underground mine, the driving forces creating ARD are removed and the mobility of hazardous metals is reduced. This ARD prevention technology avoids the perpetual treatment costs typically associated with large waste dumps and underground mine workings in sulfide ore bodies. Our ARD technologies can be applied at historic properties, during closure, and especially early in the life cycle of planned and operating sites, using our "design for closure" approach.
