Zero-Waste Mine Reclamation: Coal + Steel + Human Wastes = Soil

by Zoe Dilles

Coal has seen a worldwide growth in production in recent decades despite health as well as environmental concerns as coal combustion is cited as the primary CO2 atmospheric source. In this age anthropogenic climate change, air emissions often overshadow the threats posed coalmine waste rock, which has far-reaching ecological effects from its metal and acid contents. Mixes of coal waste rock with other substances to balance the concentration of nutrients and minerals can order to promote plant growth. Fabricated soils have the potential to reduce landfill disposal as well as mitigate the issues attendant to reclamation reliant on borrowed soils, often leading to deforestation and hydrologic changes. Continue reading

Forest Restoration May Only Have Short-term Positive Effects on Ground Water Storage in Semi-arid Aquifers

by Zoe Dilles

The already scarce water resources of the semi-arid western United States will become increasingly precarious with the progression of warming and drying climate change. When compounded with growing demand for water, this issue mandates a balanced management practice incorporating sustainable water budgets and land use. Forest restoration efforts are currently slated for an area of some 600,000 acres of National Forest in north-central Arizona, comprising nearly 1% of the state’s footprint. These treatments, anticipated to last the duration of the coming decade, will consist of selective thinning and burning of high-density conifer forest to mitigate wildfire potential and increase the health of regional forested watersheds. The impact of tree removal on surface water has been the subject of previous study but is rarely quantified in regards to groundwater resources. Especially in such a dry region, the future of water availability lies in the relationship between rainfall and recharge of deep aquifers, reservoirs that are permanently diminished through over-pumping. Continue reading

Century-old Naturally Reclaimed Mining Site Preserves Regional Biodiversity

by Zoe Dilles

Native plants are flourishing unexpected at old abandoned gold mines in Southern New Zealand in spite of the fact that no landscape remediation was done. While natural reclamation through mine abandonment has historically been the default management strategy for mining sites around the world, the strict environmental policy of today typically mandates extensive site engineering after operations cease. Turning mine sites into usable land for agriculture, forestry, or recreation often entails time-consuming and costly rehabilitation measures such as topsoil replacement and replanting. Water management directs these approaches in arid climates because mine water evaporation as a product of unique geologic settings produces often undesirably saline soils. However, the salty soil of historic gold mine sites in the South Otago region provide rare naturally occurring saline habitats that are elsewhere jeopardized by expanded farming and new agricultural processes. Continue reading