Estimation of rock load for junctions based on roof failure cases for safe mining operation

PT. Putera Bara Mitra used open mining system for mining operation, Yet the completion of study on the end wall slope stability that undertaken by geotechnical PT. Putera Bara Mitra in Northwest Pit and the occured a failure in the low wall on the 1st June 2012 led to the need for analysis and design the overall slope at the mine site. To analyze and design the overall slope, used value of the recommended minimum safety. The value was based on company for single slope SF ≥ 1.2 and SF ≥ 1.3 for overall slope. The calculation used Bichop method with the help of software slide v 5.0. Geometry improvements was done at the low slopes that originally single wall with a 30 m bench height and a slope 70° with SF = 0.781, into 4 levels with SF = 1.305. The analysis explained the factors that affect the stability of the low wall included the mining slope geometry, unfavorable drainase system, material stockpiles and seismicity factors. It was necessary to do prevention efforts to maintain the stability of the slope included the redesign to slope geometry, handling surface and subsurface water in a way to control slopes draining groundwater, vegetation stabilization using and monitoring slope using Total Station with Prism and Crackmeter to determine the movement of cracks visible on the surface.

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The Impact of Effluents from a Uranium Mine and Mill Complex in Northern Saskatchewan on Contaminant Concentrations in Receiving Waters and Sediments

Water Quality Research Journal ◽

10.2166/wqrj.1987.045 ◽

1987 ◽

Vol 22 (4) ◽

pp. 559-569 ◽

Cited By ~ 6

Author(s):

Thomas P. Hynes ◽

Randy M. Schmidt ◽

Tim Meadley ◽

Neill A. Thompson

Keyword(s):

Major Ions ◽

Mining Operation ◽

Uranium Mining ◽

Uranium Mine ◽

Northern Saskatchewan ◽

Receiving Waters ◽

The Impact

Abstract Data are provided on the release of 5 radionuclides, 17 metals and 7 major ions from a uranium mining operation in northern Saskatchewan. The downstream concentration of these contaminants is documented, and the point of “no discernible impact” is determined. Sediments in a downstream lake are monitored for uranium and molybdenum, and the post-release fate of these metals is discussed.

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Comprehensive technical support for safe mining in ultra-close coal seams: A case study

Energy Exploration & Exploitation ◽

10.1177/01445987211009390 ◽

2021 ◽

pp. 014459872110093

Author(s):

Wei Zhang ◽

Jiawei Guo ◽

Kaidi Xie ◽

Jinming Wang ◽

Liang Chen ◽

...

Keyword(s):

Coal Seam ◽

Technical Support ◽

Surrounding Rock ◽

Coal Seams ◽

Deformation Control ◽

Hard Roof ◽

Working Face ◽

Close Coal Seams ◽

Safe Mining

In order to mine the coal seam under super-thick hard roof, improve the utilization rate of resources and prolong the remaining service life of the mine, a case study of the Gaozhuang Coal Mine in the Zaozhuang Mining Area has been performed in this paper. Based on the specific mining geological conditions of ultra-close coal seams (#3up and #3low coal seams), their joint systematic analysis has been performed, with the focus made in the following three aspects: (i) prevention of rock burst under super-thick hard roof, (ii) deformation control of surrounding rock of roadways in the lower coal seam, and (iii) fire prevention in the goaf of working face. Given the strong bursting tendency observed in upper coal seam and lower coal seam, the technology of preventing rock burst under super-thick hard roof was proposed, which involved setting of narrow section coal pillars to protect roadways and interleaving layout of working faces. The specific supporting scheme of surrounding rock of roadways in the #3low1101 working face was determined, and the grouting reinforcement method of local fractured zones through Marithan was further proposed, to ensure the deformation control of surrounding rock of roadways in lower coal seams. The proposed fire prevention technology envisaged goaf grouting and spraying to plug leaks, which reduced the hazard of spontaneous combustion of residual coals in mined ultra-close coal seams. The technical and economic improvements with a direct economic benefit of 5.55 million yuan were achieved by the application of the proposed comprehensive technical support. The research results obtained provide a theoretical guidance and technical support of safe mining strategies of close coal seams in other mining areas.

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Impact of Industrial Pollution on Radial Growth of Conifers in a Former Mining Area in the Eastern Carpathians (Northern Romania)

Forests ◽

10.3390/f12050640 ◽

2021 ◽

Vol 12 (5) ◽

pp. 640

Author(s):

Cristian Gheorghe Sidor ◽

Radu Vlad ◽

Ionel Popa ◽

Anca Semeniuc ◽

Ecaterina Apostol ◽

...

Keyword(s):

Air Pollution ◽

Industrial Pollution ◽

Radial Growth ◽

Abies Alba ◽

Mining Operation ◽

Mining Area ◽

Silver Fir ◽

Local Pollution ◽

Eastern Carpathians ◽

The Impact

The research aims to evaluate the impact of local industrial pollution on radial growth in affected Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.) stands in the Tarnița study area in Suceava. For northeastern Romania, the Tarnița mining operation constituted a hotspot of industrial pollution. The primary processing of non-ferrous ores containing heavy metals in the form of complex sulfides was the main cause of pollution in the Tarnița region from 1968 to 1990. Air pollution of Tarnița induced substantial tree growth reduction from 1978 to 1990, causing a decline in tree health and vitality. Growth decline in stands located over 6 km from the pollution source was weaker or absent. Spruce trees were much less affected by the phenomenon of local pollution than fir trees. We analyzed the dynamics of resilience indices and average radial growth indices and found that the period in which the trees suffered the most from local pollution was between 1978 and 1984. Growth recovery of the intensively polluted stand was observed after the 1990s when the environmental condition improved because of a significant reduction in air pollution.

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Risk Factors for the Number of Sustained Injuries in Artisanal and Small-Scale Mining Operation

Safety and Health at Work ◽

10.1016/j.shaw.2020.01.001 ◽

2020 ◽

Vol 11 (1) ◽

pp. 50-60 ◽

Cited By ~ 1

Author(s):

Michael M. Ajith ◽

Apurna K. Ghosh ◽

Janis Jansz

Keyword(s):

Risk Factors ◽

Mining Operation ◽

Small Scale

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Economic Seafloor Massive Sulfide Mining by Japan’s Model

Volume 6: Ocean Space Utilization; Ocean Renewable Energy ◽

10.1115/omae2016-54575 ◽

2016 ◽

Author(s):

Tetsuo Yamazaki ◽

Yosuke Takeda ◽

Rei Arai ◽

Naoki Nakatani

Keyword(s):

Papua New Guinea ◽

Waste Disposal ◽

Mining Operation ◽

Massive Sulfide ◽

Sea Surface ◽

Flexible Link ◽

Private Companies ◽

Mining Site ◽

Seafloor Massive Sulfide ◽

Disposal Cost

Because of the higher Au, Ag, and Cu contents, seafloor massive sulfides (SMS) have received much attention as future commercial mining targets by private companies and nations. One of them, Solwara 1 Project in Papua New Guinea (PNG), is scheduled to start the commercial mining operation from 2018. Because the mining site is inter-island area and almost no cost is necessary for the waste disposal in PNG, the economy of the mining is expected very well. In contrast with this, because all the SMS distribution sites in Japan locate outer ocean areas and the waste disposal cost on land in Japan is very expensive, the economy of SMS mining in Japan is quite negative. In order to overcome the problems, a self-standing riser with flexible link to the sea surface platform and a primary ore separation on the seafloor prior to the ore lift-up are proposed. The improved SMS mining concept named Japan’s model is examined.

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