Alan Kuhn | New Mexico Tech (original) (raw)
Papers by Alan Kuhn
Journal American Society of Mining and Reclamation, 1998
Journal American Society of Mining and Reclamation, 1999
Most attention in surface mine reclamation is given to agronomic soils and revegetation, but recl... more Most attention in surface mine reclamation is given to agronomic soils and revegetation, but reclamation success depends on the geotechnical characteristics of the underlying earth. If the soil and rock that underlie the surface are not stable, surface treatments lack the dependable foundation needed for them to succeed. Reclamation practitioners need to understand those geotechnical considerations-material properties, structures, and processesthat affect stability. Properties of rock and soil are altered by mining, and those altered materials together with water and processing waste form often-complex mixtures of materials that must be stabilized in reclamation. Surface mining alters existing landforms and creates new ones such as pit walls, spoil and waste rock piles, tailings impoundments, and earthfills. Those structures need to be constructed or stabilized so that they can endure and support successful reclamation. Processes that affect material properties and landforms include mechanical breakage, accelerated weathering, erosion, and mass movements. Mechanical breakage and the resulting accelerated weathering combine to change material properties, usually expressed as degraded strength, that can lead to instability of landforms. Erosion, especially that related to extreme storm events, and mass movements in the form of slope failures are the most problematic processes that must be taken into account in reclaiming mined lands. These geotechnical considerations are essential in successful reclamation, and practitioners who overlook them may find their work literally sliding down a slippery slope. •
Journal American Society of Mining and Reclamation, 1998
The right post-mining land use (PMLU) can minimize reclamation and surety costs, shorten the term... more The right post-mining land use (PMLU) can minimize reclamation and surety costs, shorten the term of post-closure liability, and in some cases even produce revenue for the mine operator. Rather than an afterthought, the selection of PMLUs should be a deliberate process that takes into account a variety of factors. These factors can be grouped into four categories-environmental impacts and mitigation, land management, public interest, and feasibility. For existing mines that were planned without a PMLU, environmental impacts and mitigation may set limits on the PMLUs that can be implemented. Similarly, management policies for public lands usually limit the possible PMLUs. For new mines on private land, or on public land with forward-thinking management policies, a methodology for rational selection of PMLU can be used to include all four categories of factors. This methodology can be used also for existing mines or mines with public land policy constraints, but with fewer options and less latitude for economic feasibility evaluations. The selection process follows a sequence of screening steps that include site resource evaluation and options identification, feasibility evaluation, impact assessment, and cost/ benefit analysis. The process can be very detailed and rigorous for large mines but can be simplified for smaller, less complex mine sites. In any case, the rational selection process uses an objective methodology that produces a defensible, documented PMLU decision.
Journal American Society of Mining and Reclamation, 1998
Journal American Society of Mining and Reclamation, 1999
Most attention in surface mine reclamation is given to agronomic soils and revegetation, but recl... more Most attention in surface mine reclamation is given to agronomic soils and revegetation, but reclamation success depends on the geotechnical characteristics of the underlying earth. If the soil and rock that underlie the surface are not stable, surface treatments lack the dependable foundation needed for them to succeed. Reclamation practitioners need to understand those geotechnical considerations-material properties, structures, and processesthat affect stability. Properties of rock and soil are altered by mining, and those altered materials together with water and processing waste form often-complex mixtures of materials that must be stabilized in reclamation. Surface mining alters existing landforms and creates new ones such as pit walls, spoil and waste rock piles, tailings impoundments, and earthfills. Those structures need to be constructed or stabilized so that they can endure and support successful reclamation. Processes that affect material properties and landforms include mechanical breakage, accelerated weathering, erosion, and mass movements. Mechanical breakage and the resulting accelerated weathering combine to change material properties, usually expressed as degraded strength, that can lead to instability of landforms. Erosion, especially that related to extreme storm events, and mass movements in the form of slope failures are the most problematic processes that must be taken into account in reclaiming mined lands. These geotechnical considerations are essential in successful reclamation, and practitioners who overlook them may find their work literally sliding down a slippery slope. •
Journal American Society of Mining and Reclamation, 1998
The right post-mining land use (PMLU) can minimize reclamation and surety costs, shorten the term... more The right post-mining land use (PMLU) can minimize reclamation and surety costs, shorten the term of post-closure liability, and in some cases even produce revenue for the mine operator. Rather than an afterthought, the selection of PMLUs should be a deliberate process that takes into account a variety of factors. These factors can be grouped into four categories-environmental impacts and mitigation, land management, public interest, and feasibility. For existing mines that were planned without a PMLU, environmental impacts and mitigation may set limits on the PMLUs that can be implemented. Similarly, management policies for public lands usually limit the possible PMLUs. For new mines on private land, or on public land with forward-thinking management policies, a methodology for rational selection of PMLU can be used to include all four categories of factors. This methodology can be used also for existing mines or mines with public land policy constraints, but with fewer options and less latitude for economic feasibility evaluations. The selection process follows a sequence of screening steps that include site resource evaluation and options identification, feasibility evaluation, impact assessment, and cost/ benefit analysis. The process can be very detailed and rigorous for large mines but can be simplified for smaller, less complex mine sites. In any case, the rational selection process uses an objective methodology that produces a defensible, documented PMLU decision.