Under the Brownfields Law of 2002, EPA and other federal agencies have established a variety of programs focused on promoting and funding the repurposing of abandoned mine lands (AMLs), broadly defined as lands, waters, and watersheds in close proximity to where extraction, beneficiation, or processing of ores and minerals has occurred. Among the most promising of these initiatives is EPA’s Re-Powering America Program, pursuant to which EPA has prioritized the development of renewable energy projects on brownfield properties such as AMLs.
The Department of Energy’s National Renewable Energy Laboratory (NREL) has significantly contributed to the success of the Re-Powering America Program. As part of its initial characterization of sites on EPA’s brownfields inventory, NREL collects data sufficient to determine the renewable energy potential of each site. To date, NREL has screened over 80,000 sites for their development potential as solar, wind, biomass, and geothermal facilities.
Hard-rock mine sites, in particular, offer a number of distinct opportunities for renewable energy development. For example, they tend to be large in size, and thus can provide sufficient capacity for the installation of a large-scale wind farm or solar array in one location and are often near existing infrastructure, including roads and utilities. In addition, hard-rock mine sites can serve as excellent locations for wind farms because they are often situated in mountainous areas that receive consistent wind flow.
Development of inactive coal properties can be more challenging, due in part to the remediation and procedural requirements of the Surface Mining Control and Reclamation Act. However, the Act also offers a potential funding source for site redevelopment under its AML Reclamation Fund, a benefit not available with respect to the hard-rock mine sites.
In addition to the foregoing, there is an array of emerging technologies that can enable value extraction and new reclamation approaches based on engineered natural systems or “green infrastructure.” For example, energy recovery from wastewater at mine sites can be a cost-effective option due to the often remote locations of such sites. In addition, residuals from wastewater treatment can be used as a soil amendment to add organic matter and nutrients to the soil to create a fertile soil profile with a reestablished microbial community, invertebrates, and plants. This approach can be used to help meet Clean Water Act stormwater discharge requirements as well as regulatory limitations on direct discharge to surface waters.
The use of green infrastructure can create a revenue generating ecosystem that will help offset the cost of mine remediation. At mine sites with substantial vacant land, sustainable forestry can be used to help manage stormwater as well as generate carbon credits recognized to varying degrees under both the California and Regional Greenhouse Gas Initiative frameworks. Furthermore, engineered wetlands can help address acid mine drainage and other contaminated flows from abandoned mines and potentially serve as a secondary revenue source through the generation of water quality trading credits under the Clean Water Act.
Historically, a significant obstacle to the redevelopment of AML has been the lack of funding available to characterize and remediate these sites. This gap in funding can be reduced by incorporating renewable energy and/or green infrastructure into the mine remediation plan. The installation of a solar array during or following mine reclamation can provide an energy source to power the remediation effort or create a revenue stream to offset the cost of remediation. A similar approach can be utilized through the use of green infrastructure.
In its proposed 2018 budget, the Trump administration has requested $28.0 billion for the Department of Energy “to make key investments to support its missions in nuclear security, basic scientific research, energy innovation and security, and environmental cleanup." Of this total, $6.5 billion is designated specifically for environmental management to address “high-risk contamination facilities that are not in the current project inventory.” However, within this proposed budget, the EPA would receive $5.655 billion in funding, a 30% decrease from the enacted 2017 budget. This reduction in EPA funding may have adverse effects on the Re-Powering America program.