RESEARCH OF A LATERAL REAMER BIT FOR DIGGING PLANTING HOLE IN ROCKY ABANDONED MINE AREA

In the abandoned mine area with Karst landform in China, soils are few and thin but rocks are common, traditional planting hole diggers are unequal to work in rocks for vegetation restoration. A reamer bit with variable lateral drilling radius was designed based on the PDC (polycrystalline diamond compact) bit technology and metamorphic mechanism. Two lateral camber blades with PDC teeth were installed inside the bit body, a screw mechanism was employed as the actuation and a spatial double triangle mechanism was taken for the transmission. The curve of the camber blade was specially defined thus the reaming load was decentralized to 85.7% teeth on the blade. The kinematics of the lateral reamer bit was analysed, the mapping models from the actuation to the reaming radius and speed were established. Concrete samples were reamed indoors from 240mm to 407mm in diameter, the reaming cutting load and time length were measured and analysed. The lateral reamer bit was approved with the experiment results, this study provided equipment support for digging the planting hole in rocky abandoned mine areas and also expanded the PDC bit application.

Growth Response of Abaca (Musa textilis Nee) in Abandoned Mine Soil Amended with Oil Palm Residues

The mining industry is one of the leading sectors providing economic benefit to the community. However, mining minerals inevitably affect the ecosystem function of the land, thereby reducing ecological services provided to mankind. Soil remediation is done to restore ecological integrity while mitigating degradation processes. Thus, this study was conducted to determine the chemical properties of abandoned mine soil and to determine the effects of oil palm residues on the growth performance of abaca (Hybrid 7) grown in mined soil under nursery conditions. This study was arranged in a completely randomized design (CRD) with five treatments and four replications, namely, T1 - Mined Soil Alone, T2 - Garden Soil Alone, T3 - Mined soil + Oil Palm Sludge, T4 - Mined Soil + Oil Palm Empty Fruit Bunch (EFB) Biochar, T5 – Mined Soil + Oil Palm Vermicast. Chemical analysis of mined soil revealed extreme acidic soil condition, low organic matter, CEC, N, K, and high P content relative to soil nutrient sufficiency criteria. Mined soil contained 0.347 mg/kg Cd and 0.230 mg/kg Pb which are within the tolerable limit of 2.00 mg/ kg for Cd and 300 mg/kg (Pb), respectively. Application of oil palm residues in mined soil can significantly improve the morphology and dry matter yield performance of hybrid 7 abaca seedlings. Plants grown in mined soil amended with oil palm residues were taller, larger pseudostem girth with more and bigger functional leaves, and had a higher survival rate compared to those grown in soil derived from the abandoned mining area. Abaca plants grown with amendments had accumulated higher dry matter. Oil palm residues particularly vermicast has greater potential as soil amendment under degraded mined in Mawab, Davao de Oro.

A Framework for Ranking the Environmental Risk of Abandoned Mines in the State of Minas Gerais/Brazil

Abandoned mines are a major mining liability for the state of Minas Gerais, Brazil. The impacts and risks of abandoned mines are specific to the location and type of ore, but they cover social, economic, and cultural aspects. A central element of an abandoned mine management policy is the definition of a methodology to identify and rank characteristics of abandoned mines that pose a risk to the environment and society. This article presents a methodology for the ranking of environmental risks for abandoned mines in the state of Minas Gerais based on different evaluation factors of their external effects on the environment, safety, the population and surrounding areas, heritage and the landscape. The environmental risk of the abandoned mine area was generated to establish the “Abandoned Mine Area Environmental Risk Hierarchy”. To achieve this a multi-criteria analysis (using the Analytical Hierarchy Process (AHP)) was adopted with each preponderant factor being compared and measured. The results show that the use this framework can support in the decision-making process of an environmental agency for developing the intervention aimed at situations of greater gravity, which, ultimately, may require the use of public resources to reduce risks.

Morphology of secondary calcite deposits in an abandoned mine in the Western Rhodopes, Bulgaria

Caps and pearls are the most common morphology types of secondary calcite deposits in the abandoned mine gallery built in gneisses. Their formation is associated with the infiltration into the gallery of rainwater from the overlying marbles. The formation mechanism and morphology of these secondary calcite deposits are identical to those typical for cave caps and pearls.

Evaluating Spatial Regression-Informed Cokriging of Metals in Soils Near Abandoned Mines in Bumpus Cove, Tennessee, USA

Inorganic contaminants, including potentially toxic metals (PTMs), originating from un-reclaimed abandoned mine areas may accumulate in soils and present significant distress to environmental and public health. The ability to generate realistic spatial distribution models of such contamination is important for risk assessment and remedial planning of sites where this has occurred. This study evaluated the prediction accuracy of optimized ordinary kriging compared to spatial regression-informed cokriging for PTMs (Zn, Mn, Cu, Pb, and Cd) in soils near abandoned mines in Bumpus Cove, Tennessee, USA. Cokriging variables and neighborhood sizes were systematically selected from prior statistical analyses based on the association with PTM transport and soil physico-chemical properties (soil texture, moisture content, bulk density, pH, cation exchange capacity (CEC), and total organic carbon (TOC)). A log transform was applied to fit the frequency histograms to a normal distribution. Superior models were chosen based on six diagnostics (ME, RMS, MES, RMSS, ASE, and ASE-RMS), which produced mixed results. Cokriging models were preferred for Mn, Zn, Cu, and Cd, whereas ordinary kriging yielded better model results for Pb. This study determined that the preliminary process of developing spatial regression models, thus enabling the selection of contributing soil properties, can improve the interpolation accuracy of PTMs in abandoned mine sites.

Lost but Not Forgotten: Identifying Unmapped and Unlisted Environmental Hazards including Abandoned Mines

Environmental databases play an essential role in the management of land and communities, including mapping and monitoring environmental hazards over time (i.e., abandoned mines). Over the last century, mines have closed for many reasons, but there has been no comprehensive database of the locations of closed and abandoned mine sites kept for many regions of the world. As such, the locations of many mines have been lost from public knowledge, with no way for managers to assess the risks of land and water contamination, as well as subsidence. To address this knowledge gap, we present an integrated framework for identifying abandoned mine sites using a combination of satellite imagery, historical records, geographic evidence, and local knowledge. We tested this framework within the Newcastle, Illawarra, and Lithgow regions of NSW, Australia. We identified 61 abandoned coal mines which are currently unaccounted for in mine registries, with 56% of all mines in the Newcastle region being unmarked (N = 32), 36% in the Illawarra region (N = 22), and 20% in the Lithgow region (N = 7). These findings demonstrate that our framework has promising utility in identifying historic and unmarked environmental hazards in both national and international contexts.

Reclamation of Abandoned Mine Soil Using Biosurfactant

Mining results in enormous land damage, varying the ecosystem of microbial culture and disturbing plant life leading to annihilation of the land. Due to this researcher’s has shifted their focus to alternative methods for the sustainable development. The present study aims at environmental friendly and cost effective technique for the reclamation of abandoned mine soil using bio-surfactant. In the current investigation bio-surfactant was produced using Bacillus Subtilis MTCC no. 1427 on 20% spent wash collected from distillery unit. The mined soil with bio-surfactant was able to minimize heavy metal concentration and the plants grown on this soil were healthy similar to the results of the agricultural soil. Keywords: Mining, Abandoned, Reclamation, Heavy Metals, Re-vegetation, Bioremediation.