Potential Use of Organic- and Hard-Rock Mine Wastes on Aided Phytostabilization of Large-Scale Mine Tailings under Semiarid Mediterranean Climatic Conditions: Short-Term Field Study

Abstract

The study evaluated the efficacy of organic-and hard-rock mine waste type materials on aided phytostabilization of Cu mine tailings under semiarid Mediterranean conditions in order to promote integrated waste management practices at local levels and to rehabilitate large-scale (from 300 to 3,000 ha) postoperative tailings storage facilities (TSFs). A field trial with 13 treatments was established on a TSF to test the efficacy of six waste-type locally available amendments (grape and olive residues, biosolids, goat manure, sediments from irrigation canals, and rubble from Cu-oxide lixiviation piles) during early phases of site rehabilitation. Results showed that, even though an interesting range of waste-type materials were tested, biosolids (100 t ha −1 dry weight, d.w.) and grape residues (200 t ha −1 d.w.), either alone or mixed, were the most suitable organic amendments when incorporated into tailings to a depth of 20 cm. Incorporation of both rubble from Cu-oxide lixiviation piles and goat manure into upper tailings also had effective results. All these treatments improved chemical and microbiological properties of tailings and lead to a significant increase in plant yield after three years from trial establishment. Longer-term evaluations are, however required to evaluate self sustainability of created systems without further incorporation of amendments.

Phytostabilization of mine tailings using compost-assisted direct planting: Translating greenhouse results to the field

“…A further complication is the need for drought-tolerant plant species which are generally adapted to the alkaline conditions found in most arid environments (Saslis-Lagoudakis et al, 2015). Therefore the phytostabilization process often must be “assisted” through the addition of amendments that may include compost, biosolids, lime, and/or fertilizers (Brown et al, 2004; Clemente et al, 2012; Conesa et al, 2007; Lee et al, 2014; Li and Huang, 2015; Madejón et al, 2010; Santibañez et al, 2012). The vegetative cap created by assisted phytostabilization should result in the phyto-catalyzed stabilization of inorganic contaminants in the root zone driven by organic matter, plant root exudates and the associated rhizosphere microbial community (Mendez and Maier, 2008; Santibañez et al, 2012).…”

“…Therefore the phytostabilization process often must be “assisted” through the addition of amendments that may include compost, biosolids, lime, and/or fertilizers (Brown et al, 2004; Clemente et al, 2012; Conesa et al, 2007; Lee et al, 2014; Li and Huang, 2015; Madejón et al, 2010; Santibañez et al, 2012). The vegetative cap created by assisted phytostabilization should result in the phyto-catalyzed stabilization of inorganic contaminants in the root zone driven by organic matter, plant root exudates and the associated rhizosphere microbial community (Mendez and Maier, 2008; Santibañez et al, 2012). Further, there should be limited above ground biomass accumulation of metal(loid)s to prevent the movement of contaminants into the surrounding ecosystem and food chain through grazing or plant death and decay (Henry et al, 2013; Mendez and Maier, 2008; Pérez-de-Mora et al, 2011).…”

“…There are few reported field studies that have evaluated the feasibility of assisted phytostabilization of mine tailings in semi-arid environments (Brown et al, 2009; Clemente et al, 2012; Cordova et al, 2011; Pardo et al, 2014; Santibañez et al, 2012). The goal of this study was to determine whether assisted phytostabilization could be successfully implemented at the Iron King Mine and Humboldt Smelter Superfund (IKMHSS) site which has mine tailings that are characterized by extreme acidity and high levels of arsenic, lead, and zinc (Root et al, 2015).…”

The Economic-Environmental Impacts of China’s Action Plan for Soil Pollution Control

“…As shown in Table 3, of the CNY 582.3 billion investment in Construction, most investment would be used to renovate tailing reservoirs, solid waste storage and landfill sites. As by-products of mining and mine-processing activities, tailings are a mixture of sand, fine-grained solid materials, water and significant quantities of heavy metals [28]. Tailings are generally deposited in open-air tailing reservoirs without any treatment [29].…”

Role of Melatonin to Enhance Phytoremediation Capacity

“…Furthermore, in semiarid mining regions, plant species should also be able to adapt to drought. Metal tolerant native plants are usually selected because they demonstrate tolerance to local environmental conditions and usually grow well and proliferate [18].…”