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By Ivo Dreiseitl, Kondratenko. Anatoly

"The second prime area within the Interoceanmetal Joint Organization exploration area named H22 was delineated in 2013 with the goal to ensure sufficient nodule reserves for profitable mining operations and processing.The knowledge base for area H22 has been obtained from archive materials. The geological situation can be characterized as follows: the sea bottom is represented by tectonic blocks oriented in a sub-meridional direction. According to swath mapping, the depressions (troughs) are contoured at depths of 4500-4600 m while the tops of horsts occur at 4300-4350 m. Volcanic relief occupies 6% of the H22 area; in the eastern part a multicone volcano was detected. Its area at the base is 153 km2. The maximum height of a cone above the base is 850 m. The crystalline basement composed by tholeiitic basalts of late Oligocene age is covered by about 100 m of sediments. Semi-consolidated to consolidated calcareous nanofossil sediments of the Marquesas formation are deposited on the basement. Higher up in the profile sediments of the Clipperton formation occur. They are represented by unconsolidated siliceous (Radiolaria, Diatom) ooze. Sediments containing calcium carbonate have not been detected. Where opaline silica (or CaCO3 if any) content is below 5%, the sediments belong to zeolitic clays or red pelagic clays. Grain size composition of the seabed and the near-seabed sediments in H22 classifies them into clayey silts."

Sep 1, 2014

By R. L. Andrew

The southwest Pacific has produced at least four of the world’s premier porphyry copper-gold deposits, and the current level of exploration is likely to produce even more. An appreciable amount of gold is being produced with this copper, with obvious economic advantages. Gold content, in addition to their large size, makes the southwest Pacific’s porphyrycopper-gold deposits very attractive exploration targets. The recognition of telescoping and overprinting of porphyry systems has produced a greater awareness of the likely surface expressions, in particular the significance of advanced argillic lithocaps in porphyry exploration. The recognition of the spatial and genetic association of porphyry copper and epithermal gold systems (Sillitoe, 1972), as in other parts of the world, has had important implications for exploration in the Asia Pacific region.

Jan 1, 1995

By K. Awuah-Offei

Energy efficiency has become significant due to cost and environmental considerations. Comminution and material handling have been identified as the two most energy intensive processes in mining. The objective of this work was to evaluate truck-shovel energy efficiency strategies using discrete event modeling. Energy audits and time and motion studies were conducted at a surface coal mine to acquire data. A discrete event simulation model of truck-shovel operations was built in Arena® and validated with the field data. The model was used to evaluate the effect of using a larger shovel, and optimizing truck-shovel matching on fuel efficiency. The results indicate that using a larger excavator increases the fuel efficiency of the operation while optimizing truck-shovel matching does not. However, using a larger shovel will lead to under-utilization of the shovel. This work shows the potential benefits of using discrete event simulation to model energy efficiency of mining operations.

Jan 1, 2012

The support of the roof in coal mines remains a critical safety issue with 3 fatalities from roof falls in 2007 and 430 injuries from roof falls in 2006. A snapshot survey by the authors of room design and support details as well as unplanned falls of ground in the industry revealed some useful data concerning support use, seam details, fall dimensions, bolt lengths and spacing and the stand-up time.

Jan 1, 2009

By Samer Sadek

The Georgia Department of Transportation (GDOT) undertook an exploratory feasibility study to one of the most ambitious tunneling projects in the United States. HNTB Corporation was retained to perform the study, deemed the Atlanta North-South Tunnel, which is approximately 7 miles long and consisting of four lanes (or six lanes) starting at the southern terminus of SR 400 extending to the south connecting with the northern terminus of I-675, providing substantial relief to the Downtown Connector (I-75/I-85), the most congested portion of Atlanta?s freeway system. This paper summarizes the analysis performed during the first phase of this challenging assignment which, if constructed, would be one of the longest roadway tunnels ever built in the United States.

By Satoshi Honda, Mitsuru Shimizu, Tatsuji Nagao, Motoaki Kurisu, Hirokazu Izumi, Toshinori Takahashi, Hiroyuki Itoi

"1. INTRODUCTION Grade separation of roads and railway tracks is an effective method for solving traffic-related issues in cities. However, in urban areas where the existing traffic infrastructure is already overcrowded, construction of new roads often faces problems especially in the proximity of existing structures. This paper summarizes the construction plan and results of new road tunnel construction in the proximity of the piers of elevated tracks on the Tokaido Shinkansen railway.2. SUMMARY OF CONSTRUCTION AND ISSUES Auxiliary Route No. 26 as specified in the Tokyo urban plan is a project by the Tokyo Metropolitan Government, covering the construction of a new road with a total length of 22.3 km currently on the way to completion. In Shinagawa Ward, Tokyo, Auxiliary Route No. 26 is designed to cross the railway tracks of the Yokosuka Line and the Tokaido Shinkansen Line, so for this project, the East Japan Railway Company (JR East) was commissioned to design and build a road crossing under the railway tracks (Sumiyoshi Underpass). Figures 1 through 3 show a sketch of the Sumiyoshi Underpass. The Sumiyoshi Underpass was planned as a two-lane tunnel for vehicles, which was to cross under the railway tracks of the Yokosuka Line and the Tokaido Shinkansen Line at an angle of 70 degrees. The structure concerned is a single-story single-span box culvert structure with the following dimensions: 11.5 m wide, 7.7 m high and 31.6 m long. The Tokaido Shinkansen Line tracks were constructed on a girder-type elevated bridge built in the 1960s, and the foundation piles of the piers (P7 and P8) in the proximity of this crossing box culvert of RC structure were constructed using an earth drill method. The crossing structure for this project is located extremely close to the piers of the Tokaido Shinkansen railway tracks, with a minimal separation of 0.4 m, and the most significant issue of this project was construction in a manner that would not obstruct the normal operations of the Tokaido Shinkansen (Figure 4). Initially, we considered installing a temporary earth retaining structure in the proximity of the piers, cutting the ground and building an RC box, but concluded that it would be very difficult to apply this method because of probable excessive displacements in the Shinkansen railway piers. That is why we decided on the use of a non-open cut method in order to minimize the impact on the piers."

Jan 1, 2016

By David Jurich, Joseph N. McDivitt

INTRODUCTION South Coast Water District (SCWD) operates the Beach Interceptor Sewer Tunnel(BIST) in South Laguna, Orange County, California between Monarch Beach and Aliso Beach (Figure 1). The 10,200-foot long BIST houses a 24-inch gravity Techite sewer pipeline critical to the SCWD Sanitary Sewer Collection System. The original tunnel and sewer pipeline were constructed in 1954 and the sewer line was replaced in 1974.Periodic inspections by sewer pipeline maintenance crews documented deterioration of specific intervals of the tunnel. Rotting timber supports and rock falls in the tunnel as a result of the deterioration were endangering the sewer pipeline and a 731-foot section of tunnel located at Thousand Steps Beach was determined to be in immediate need of repairs. SCWD and consultants Hatch Mott MacDonald (HMM) and Tetra Tec prepared a Work Plan for emergency tunnel stabilization and pipe protection measures that was implemented in January 2007. Normal access to the beach and the section of tunnel requiring repairs was limited to public stairs referred to as Thousand Steps and, therefore, all materials and equipment needed for the work were transported to the beach by ocean-going landing craft. Additionally, the emergency repairs had to be completed without taking the pipeline out of service. Numerous environmental, logistical and operational requirements had to be overcome to complete the challenging emergency repairs. GEOLOGICAL SETTING The Laguna Beach area is located in the Peninsular Ranges of Southern California. The project area is located on the southwest flank of Niguel Hill along marine wave-cut cliffs and slopes. The tunnel was excavated in the San Onofre Formation, a marine deposit, characterized by abrupt lateral and vertical changes in lithologies that vary from boulder to cobble and gravel size breccias to medium coarse sandstones with gravel, sandy claystone and siltstone. The interval of the tunnel that required repairs is located within the San Onofre breccia, a moderately-to-well cemented, poorly bedded to massive unit with angular to subangular boulder and cobble sized clasts of schist. The sandy silt matrix of the breccia is composed of quartz, feldspar and schist grains (Figure 2). GENERAL TUNNEL DESCRIPTION The approximately 6-feet high by 6-feet wide 10,200-foot-long BIST was hand mined in 1954 at the base of the coastal cliffs. Primary access is through twenty-one access adits from public and private beaches. The tunnel is located in an easement that extends beneath private property with residential structures situated 50 to 80 feet above and horizontally in close proximity to the tunnel alignment. Most of the tunnel is horse-shoe shaped and unsupported, but approximately 3,000 feet is supported by timber

Jan 1, 2007

By L. Tonc

In 2004, the engineers at the Deer Creek Mine located near Huntington, Utah initiated the ventilation planning to exploit a remote area of the mine?s reserves. This area was located under a mountain which would not allow for the incorporation of an additional shaft or portal access near the proposed longwall panels. With this constraint along with the desire to maintain a two entry gate road system and the expected condition of frequent coal wash outs a ventilation plan was established. Different options were examined that included; increasing the current exhaust fan power, adding another exhaust fan installation, converting the ventilation fans in the active portion of the mine to a forcing system, and modifying the ventilation system in the active area of the mine to a push-pull system. The push-pull ventilation system was ultimately selected. This paper details the design process of the ventilation system upgrade, the procurement process for the new fans, and the new fan startup testing.

Jan 1, 2009

By O&apos

Southern Ohio Coal Company (SOCCO) and the U.S. Bureau of Mines have identified techniques to optimize the use of scrubbers on continuous miners. The techniques provide maximum respirable dust control while maintaining a high output. The use of radio remote control and scrubber help to achieve greater advance between lifts by locating the operator in fresh air during the mining cycle. He is also kept away from newly exposed roof, which is not supported. An alternative to fan-powered scrubber was also evaluated at SOCCO. A high-pressure water-powered scrubber system eliminated the noise associated with fans, and achieved an intrinsically safe system. Experience in the use of these scrubber systems and remote control at SOCCO are discussed.

Jan 1, 1990

By A. M. Radigan, W. G. Prast

M.S. Azun The authors' paper did not explain the facts and reasons why state companies are established and what their role is in international industrial mineral trading. Also, I do not agree with the conclusion implying that the main goal for state companies is to capitilize natural resources. Almost all state companies are founded by certain laws and their activities are arranged by state regulations. Their only aim is to operate mineral deposits for their people and to protect the rights of the people. Although some ore deposits, such as nonstrategic or small, may be exploited by privately owned companies, the state has the right to control the operation and production. Activities of state companies may or may not be widened because of the character of the deposits and the importance of the mineral market involved. For some countries, although governments may occasionally change hands, the policy of the mineral trading system is not affected by this change. There is no doubt that any government desires to make more earnings to increase GNP, when it is involved in operating and trading mines. It wants to produce and sell the finished products, instead of unprocessed ones, if possible. When it is known that some mineral deposits are relatively rare, such as Turkish boron deposits, the government can nationalize the mines to control production and affect the market. If there is an abundance of a certain mineral in the market, the government can cut production and set a floor price, such as Canadian potash. Also, when production of a specific mineral is unique, such as Turkish chromite, the price of such mineral may be set by correspondant government. One may add that if some governments with their state companies produce a certain mineral in a larger amount, they may decide to establish a cartel to protect their production and price. These are the facts followed by government-owned state companies and partially government-owned companies. The reason being charge of many deposits by the state companies is always the same: "protect" the mineral rights of the people.

Jan 2, 1984

By D. Brady

There are many examples, historical and recent, from the underground coal mining industry where during emergency response the response and ultimately the outcomes, could have been significantly improved if adequate systems had been in place for the collection and management of relevant information preceding the incident, the acquisition of information during the incident and the use of the information for risk mitigation and decision making purposes. The subject and process of knowledge management is possibly the most critical for would be rescuers of endangered coal mine workers, as it has been demonstrated at numerous coal mine incidents that a lack of or mismanagement of crucial information can be fatal for both the rescuer and/or the endangered coal mine worker. This paper will underline the scope and importance of robust knowledge management systems for emergency response within the underground coal mining industry and the process by which it is being achieved within the Queensland Mines Rescue Service and the NSW Mines Rescue Service.

Jan 1, 2012

By J. M. Dempsey, R. A. Litle

Asarco Incorporated’s Omaha, Nebraska refinery site and the City of Omaha’s downtown redevelopment projects are the perfect example of the marriage of the Brownfield and Sustainable Development strategies. Nebraska’s largest voluntary site remediation project created a focus point for redevelopment and has spurred over $1 billion in economic investment within a 1-mile radius of the site. Asarco was faced with options of very expensive and uncertain facility upgrades or a shutdown. Local leaders, Asarco, and regulators worked together to convert a controversial and complex site to a park-like redevelopment area with numerous long-term benefits to the City and the environment.

Jan 1, 2004

By K. Boakye

This paper presents the results of a review of historic blast design practices at the Dragon Products Company, LLC (Dragon) Quarry Operation, along with the results of two different blast design vibration monitoring programs. A blast pattern design modification was initiated to determine if production volume per shot could be increased and highwall instability could be decreased. A vibration monitoring program was undertaken to investigate peak particle velocity (PPV) and relate the data to the blastability of the jointed onsite rock mass, utilizing the relationship between PPV and dynamic stress and strain. The Dragon Quarry Operation has historically used a 6-in. diameter, 14-ft by 14-ft production blast pattern, with blast holes loaded manually using cartridge style explosive products. In 2011, Quarry Operations introduced a 6-in diameter, 16-ft by 16-ft production blasting pattern, using pre-mixed, truck-loaded, bulk emulsion/ammonium nitrate/fuel oil (ANFO) blends. This paper summarizes the results of the blast design modifications, the results of the vibration monitoring data, and describes how production blasting and excavation at the Dragon Quarry has benefited from such modifications.

Feb 27, 2013

By Hyung-woo Kim, Kiyoung Sung, Sup Hong, Jung-Yeul Jung

Many concepts for the commercial production of deep-seabed manganese nodules have been studied since the 1970s. However, the bearing capacity of the deep seabed is not strong because it is composed of fine particles with high moisture content. So it is impossible to carry manganese nodules in the collection system. Therefore, the validity of continuous mining by riser pipe from the seabed to the vessel is highly appreciated. A continuous mining system is composed of mining vessel, lifting pipe, buffer system, transport tube (flexible pipe), and self-propelled mining robot. A conceptual diagram of this system is shown in Fig. 1(a). Korea Research Institute of Ships and Ocean Engineering (KRISO) developed a deep-seabed self-propelled mining robot called "MineRo" to collect manganese nodules in 2012 (as shown in Fig. 1(b)). In 2013, real sea experiments at around 1380 m depth were carried out to evaluate the collecting and driving performance of MineRo. However, we found that the roller in MineRo did not work well at times. To elucidate the problem, we analyzed the rheological characteristics between the bushing and drive shaft under deep-water conditions.

Sep 1, 2014

By Aijuan Zhang, Liang Zhao, Yutao Wang, Yu Bao

In the green backfilling mining of underground coal mines, gangue in a coal seam is used to replace and fill goafs. However, the gas drainage time changes in the amount of gangue output and order in the extraction sequence of stope blocks, thereby changing the production output. A multi-objective integer programming model was proposed to solve this based on an improved non-dominated sorting genetic algorithm. The results show a feasible gangue filling rate can be found and the extraction sequence for a long-term planning time is optimized. It increases the planned annual output by 26% and reduces equipment idle time.

May 23, 2022

While SME is hosting its Annual Meeting at the Phoenix Convention Center, Feb. 28 to March 3, one of the finest collections of mining history will be on display just 15 blocks away at the Arizona Mining and Mineral Museum. Inside the museum, visitors will be treated to a treasure trove of minerals, gems, me¬teorites, rocks, fossils, mining artifacts, historical exhibits and interactive displays on modern mining. The museum is located at 1502 West Washington. For SME Annual Meeting attendees, this is a free, eight-minute Dash bus ride 15 blocks west of the Phoenix Convention Center.

Jan 1, 2010

By Todd Minoski, Matthew McElhinney, Morgan Sears, Craig Compton

In an effort to advance the science underlying ground control engineering, researchers with the National Institute for Occupational Safety and Health (NIOSH) are frequently involved in field studies at collaborating mines. Often, these field studies involve visiting the mine site, instrumentation installation, and data acquisition. Each of these aspects involve potential risks to NIOSH employees. As an organization whose mission it is to promote the health and safety of mine workers, the health and safety of our workforce is paramount. This paper provides documentation of the best practices followed by NIOSH employees who are tasked with visiting and conducting work at underground and surface mines. This includes Mine Safety and Health Administration (MSHA) approved training, mine site specific training, and hazards associated with all aspects of mining that could be encountered by the employee. Additionally, this paper details best practices associated specifically with instrumentation installation including the mitigation of hazards associated with the proper equipment handling, drilling, and the mine environment. The information showcased in this paper can be used as considerations for industry practitioners such as mine operators, consultants, and academic researchers engaged in the installation of instrumentation in the field. Furthermore, the best practices detailed in this paper can be used as a foundation for agreements made between mine operators and researchers to ensure safety procedures will be followed while on mine property. This will result in enhanced safety of both researchers involved in field studies as well as mine employees tasked with assisting and accompanying those researchers.

Feb 1, 2024

By T. F. Tomb

Although the number of operating longwalls (approximately 100) has remained relatively constant over the last five years, longwall production levels have significantly increased and have in some cases more than doubled. As a result of the increase in production, control of respirable dust continues to be a problem. Therefore, the Mine Safety and Health Administration (MSHA), Pittsburgh Health Technology Center, Dust Division, initiated a study to investigate the availability and adequacy of technology for controlling dust on longwall mining operations. The study involved 23 longwall mining operations in three different Coal Mine Safety and Health Districts. Each operation was visited for a full shift. Respirable dust samples were collected on face personnel and at fixed locations along the face. Parameters in place to control dust were noted with special emphasis being placed on obtaining quantitative data relative to ventilation, headgate dust controls, cutting drum sprays, external machine sprays and cutting sequence. Attempts were made to correlate dust control parameters in place at the time of the visit to dust concentrations measured at the tail, on the tail shearer operator and to the average concentration of dust determined from averaging all the measurements from the occupations sampled. The parameters in place to control dust were also compared to the gamut of technology known to be available to control dust. This paper presents a discussion on the effectiveness of the parameters in place to control dust and on the availability of technology for the control of dust on longwall mining operations.

Jan 1, 1990

Newmont?s Twin Creeks Mine, located in northern Nevada, is producing gold ore from surface mining operations. The ore is currently processed at three different on site facilities depending on the ore type and the grade. The processing facilities operate under stringent geochemical blending constraints that must be met from mine ore deliveries and off site sourced ore. To analyze various strategic options, the technical team utilizes the mathematical optimization approach. However, due to the size and the complexity of the operation, there are unique challenges in optimizing life of mine production scheduling. This paper describes those challenges and the methodology developed to take advantage of different scheduling software systems that effectively compensate each other and result in reasonable guidance. The paper also describes how those scheduling results are reflected in detailed mine plan and cost estimate work.

Feb 27, 2013

By D. W. Wu, M. T. Haque

A novel impedance probe has been commissioned specifically for capturing fast dynamic information about filtration processes. It provides an attractive alternative to more complex measurement techniques in situations where the slurry system is primarily one-dimensional. The probe can monitor mud-line, slurry densification and drainage. Dynamic variations in cake permeability are obtained by combining dynamic mud-line information obtained with the probe and filtrate rate data derived from a leaf test apparatus. The measurements are re-viewed in relation to micro structural measurements obtained on iron ore filter cakes. The practical significance of these measurements for optimization of the filtration process is discussed.

Jan 1, 2000