Search Documents

By Samer Sadek, Phoebe Cheng, Changmo Kwon, Myat Ohn

BART Facilities Standards (BFS) Structural Criteria is a living document that governs planning, design, and construction of all BART projects. Since its development, the document undergoes incremental changes and updates to reflect policy changes, changes in local, State, or national design codes and guidelines, advancements in engineering and technology, or based on the performance of past built infrastructure. In 2020, the BFS-Structural Criteria underwent a comprehensive update and was released with BFS version 3.2. This paper summarizes the updates to the Tunnels and Underground Structures Section of the Structural Criteria, and provides insights to the basis and logic of the requirements.

Dec 1, 2022

By F. Alsobrook

Coleman Quartz Inc. has a long history as the sole U.S. producer of lascas for the cultured quartz growing industry based on its unique deposits in Arkansas. Since 1989 the company has also been producing metallurgical grade silica for the ferrosilicon industry from a deposit of unusually pure Arkansas novaculite. This paper chronicles Coleman's trans-formation of an abandoned railroad ballast quarry into a generator of $1.5 million in annual sales to a nontraditional novaculite market. Potential additional applications for this high quality silica rock will also be mentioned.

Jan 1, 1992

By Francesco Chiappalone, Marco Invernizzi, Franco Gasperin, Brad Yoder, Fabrizio Fara

The Ship Canal Water Quality Project includes a 2.7-mile, 18-ft and 10-in internal-diameter tunnel that extends from Ballard to Wallingford, two popular neighborhoods in the West of Seattle. During the TBM Main drive a 12' × 12' boulder with variable strength up to 47,000psi was encountered resulting on signicant damages to the Cutter ead. The rst part of this paper describes the design and construction of an underground recess in front of the TBM to create a safe working environment for the TBM repairs. The second part describes an injection campaign performed to seal an unforeseen water inow appeared during the excavation of the 11 Avenue Diversion Structure.

Jun 23, 2024

By J. Sattarvand, P. C. Augustine

Despite significant safety improvements, the mining industry remains one of the most hazardous occupations globally and the evacuation of Miners, when an uncontrollable incident occurs in the mine, is the best bet to saving lives. However, Human factors/behaviors during an emergency are likely to influence the evacuation performance. Other industries have made a significant effort to determine these human factors that can impede evacuation performance, however, the current state-of-the-art in mine evacuation or self-rescue is that the evacuation route is predetermined, and a static sign is used to direct miners to the predetermined safe location. This method is limited in representing actual conditions that arise in a real emergency, neglecting the different behaviors displayed by humans. As optimization of the evacuation of a mine plays a fundamental role in emergencies and modeling evacuation behavior and movement of miners is a complex task, this research utilized Agent-Based simulations to simulate the evacuation behavior and performance. It was observed that people with the smart evacuation device made fewer mistakes and arrived at the safe place in less time compared to those have no access to the device. The Mathematical model used in optimizing the shortest path to a safe place is also explained in this paper.

Jun 25, 2023

By A. Tordoir, S. S. Kanchibotla, W. Rogers, E. Engmann, B. Bisiaux, S. Ako

Blast-induced rock mass displacement can have a significant impact on ore loss and dilution. The mischaracterization of the grade boundaries both prior to, as well as a result of, blasting can lead to significant financial losses due to ore loss and dilution. Ore dilution occurs when waste material is miscategorized as ore and sent for processing or stockpiling, diluting the run-of-mine head grade and recovery. Ore loss takes place when valuable mineral is miscategorized as waste and sent to the waste dumps, thus never being processed and recovered. Extensive research has been conducted at the University of Queensland over the last fifteen years to understand the impact of blast movement on ore loss and dilution. Recent outcomes of this research have led to the development of innovative tools and techniques to measure and model blast movement. These techniques have been implemented at the Ahafo gold mine in Ghana to understand blast movement dynamics and to implement solutions to reduce blast-induced ore loss and dilution. These solutions are validated through controlled trials and have been incorporated into site standard operating procedures.

Jan 1, 2012

By Randall D. Peterson

Strip mining with draglines and other surface equipment has traditionally been the method of choice for mining shallow deposits. This is particularly true for soft deposits that require little or no blasting. High rates of productivity and low operating costs have set this standard. However, these methods can be improved. Strip mining methods are batch processes and difficult to accommodate in processing. Moreover, they are encumbered with overburden removal, reclamation expense, and human inefficiencies. This paper describes the invention of a novel shallow earth mining technique called the Softwall Mining Method. Softwall Mining is an adaptation of longwall mining for loose earth conditions. The method was specifically invented for recovering phosphatic clay ore from beds in North Central Florida, but is likely to be suitable for a number of other minerals as well. Potential deposits for which the method may be well suited include placers, disseminated deposits in soft host rocks, bauxite, soft coals and lignite deposits, and other deposits where overburden will subside readily and where the ore can be hydraulically broken and slurried. Unit operating cost advantages are expected over the current dragline systems used. The Softwall mining advantages are its high rates of productivity, control and automation of the mining process, reduction of dilution and waste, and elimination of the majority of stripping and reclamation.

Jan 1, 1998

By Eduardo Velasco, Paz Navarro, Alfonso Navarro, Claudio Cimiotti, Alejandro Sanz, Nick Karlin

The LA Effluent Outfall tunnel is a 7-mile long, 18' internal diameter, secondary treated effluent discharge tunnel currently under construction by Dragados USA for the Los Angeles County Sanitation District No. 2 (LACSD). The purpose of this tunnel is to add redundancy and increased capacity for discharge of secondary treated effluent from the LACSD’s Joint Water Pollution Control Plant, located in Wilmington, California within Southern Los Angeles County. Current discharge from this facility flows through two existing tunnels of 8' and 12' horseshoe profile, constructed in 1937 and 1958, respectively. When the new tunnel is complete, it will add an additional capacity of 670MGD in peak wet weather flow conditions. Geology of the roughly 7 mile long tunnel was divided into six reaches by the contract documents. Tunnel Reaches (TR) 1 to 3, comprising 19,550' will be excavated in alluvial sands of the San Pedro and Lakewood formations, with cover ranging from 45 to 90 feet. In this reach the tunnel intersects the seismically active Palos Verdes fault Zone. TR 4 is a 1,600' transitional zone between alluvium and the rock formations of the Palos Verdes (PV) Hills, comprised mostly of Malaga Mudstone. TR’s 5 and 6 total 15,591', and are within the rock formations of the PV Hills with overburden ranging from 315' to 475'. The primary constituent of the PV Hills is Altamira

Jun 13, 2021

By Larry Murphy, Mohammad R. Jafari, David M. Giel, Sharat K. Kalluri

"Built in 1940’s to provide a key roadway arterial between New York and Boston, the Heroes Tunnel is the only highway rock tunnel in the state of Connecticut and is part of the Wilbur Cross Parkway. This 365.0 m long tunnel consists of two barrels, each with two lanes of traffic, and carries over 71,000 vehicles per day. For nearly 70 years, the tunnel has seen millions of vehicles pass through but time has taken its toll and now the tunnel lining, ventilation system and radial section joints are significantly deteriorated and in need of rehabilitation. Owned and maintained by the Connecticut Department of Transportation (CTDOT), CTDOT initiated a unique managed approach to mitigate the risk, social impacts and financial implications associated with rehabilitation of this tunnel. This new approach consists of performing field inspection and conducting a comprehensive study to explore six rehabilitation options, including construction of new tunnels and enlarging the existing tunnels. The main criteria for this study are: Impact on traffic and the resulting delay cost; Construction cost; Construction duration; and Construction complexity. This paper will present the results of the alternative study. PROJECT BACKGROUND Location and Importance Heroes Tunnel is located in the State of Connecticut within the Town of Woodbridge and the City of New Haven near the Town of Hamden border. Heroes Tunnel is the only true highway tunnel in the State of Connecticut. The tunnel is part of the Wilbur Cross Parkway (Route 15), a scenic connection between Hartford and New York. Originally constructed and opened to traffic in 1949, the tunneled portion of the parkway passes through the West Rock Ridge. The tunnel was originally named West Rock Tunnel, but was re-designated as Heroes Tunnel in 2003. Route 15 is a vital roadway within the State transportation infrastructure. In the vicinity of Heroes Tunnel, Route 15 carries approximately 71,000 vehicles daily. Locally, Route 15 provides access to residences, shopping centers, and points of interest, as well as other state roadways. Regionally, Route 15 connects New York to the Hartford area and serves as an alternate expressway route to I-95 and I-91. The tunnel is approximately 365.0 m long and passes through the West Rock Ridge. West Rock Ridge is an 11.3 km long rock ridge located on the west side of New Haven. A network of suburban streets abuts the mountain on all sides and a seasonal paved park road climbs to the crest of the ridge. Figure 1 depicts the tunnel topography and location."

Jan 1, 2016

By Michael Robert Hodson

I. Introduction The free market cash price of aluminium in the third quarter of 1985 is approximately $1000/tonne, well below the short as well as the long run marginal costs of production. The current disparity between marginal costs and price, as well as the pattern of prices since their high level in 1980, has led many economists to question whether prices are governed by the 'fundamentals'. Prices, some would argue, are the result of speculation; and speculation is irrational, little influenced by the fundamentals of the industry. The object of this paper is first to examine the relation between the fundamentals and price. A number of simple models are formulated and some empirical evidence is given to show that prices are not very different from costs. There are good reasons why costs and prices have fallen since 1980. Second, the connection is drawn between the fundamentals and speculation. To do this the concept of 'rational expectations' is defined and applied to a model of the aluminium industry. Then speculation is introduced into the model and the characteristics of the solution are examined. The object is to discover the new factors that determine prices and the basic change in the nature of the solution that is caused by speculation. 2. Prices and the Simple Supply-Demand Model Consider a simple model of the aluminium industry. Demand, D, is determined by economic activity, A, given exogenously, and inversely by the price, P. Supply, Q, is determined by the inverse of the rnarginal cost curve, and so varies inversely with exogenous factor costs, C, and directly with price. Price is determined by the equality of supply and demand. Given the equilibrium level of demand, price in this model is equal to the rnarginal cost of producing the required level of demand, P = MC (Dl. Algebraically, [ ] How well does this simple model explain the change in prices during the last five years? Table I shows the LME cash price and the estimated marginal cost of producing consumption during the second quarters of 1980 through 1985. The figures in the table show that price and the marginal cost of supplying demand both fell between 1980 and 1982, rose in 1983 and by 1985 had fallen again. Only in 1984 is the direction of change different. And during the 1980 to 1985 period, marginal costs fell by approximately $560/tonne while the LME cash price fell by $678/tonne. There is a correspondence between the fundamentals of cost and price over most of the individual years and the period as a whole.

Jan 1, 1986

By Tony Walsh

Australian Stock Exchange Limited (ASX) -ASX is ranked 9th in the Morgan Stanley Capital International (MSCI) Index – only 2.02% of that Index. -1520 companies – 400+ mining & mining exploration. -Over 50% of Australians own shares in ASX listed co.s -Disclosure standards play a vital part in providing investors with confidence, thereby building depth and liquidity in the market.

Jan 1, 2003

By T. M. Biddle

If an accident occurs at a mine, the mining company, its parent and affiliates, and its supervisory employees may face substantial -- and sometimes unexpected -- liabilities and costs. This presentation surveys the likely sources for post-accident exposure, including wrongful death and personal injury claims, mine closure/operational disruptions, and government civil and criminal actions against the company and its employees.

Jan 1, 1986

By Duane A. Smith

Introduction From the days of the Spanish in the eighteenth century, Colorado's San Juan mining district has attracted miners and public interest. The Spanish left behind names - San Juans, La Plata, Animas, legends of lost mines, and the remains of a few scattered mining operations. They came, but did not stay. Again in 1860-61, as a spinoff of the Pike's Peak gold rush, prospectors climbed the mountains and descended into the canyons searching for gold. They found some, not enough to convince them to remain and confront the isolation, often hostile environment and the Utes, who rightfully felt this to be their home. Not until the 1870s did miners come to stay. In their wake little camps grew in the high valleys and squeezed into narrow canyons. Nowhere else in Colorado were there more rugged mountains, a higher average elevation, nor a climate that one old Swede said was "three months of mighty late fall and nine months of winter." The San Juans proved eventually to be a mineral treasure chest. At the moment, however, the prospectors sought gold. Then they discovered silver deposits and the first rush was on. It got started just in time to be completely overcome by the Leadville excitement. At Leadville, investors almost fell over themselves to buy claims and stock in the hopes of becoming another millionaire like Leadville's own Horace Tabor. The San Juaners could only look from the sidelines and speculate how it might have been had fate been kinder. Fate was seldom kind, as these pioneers quickly discovered. From the mid-1870s on, the San Juaners wrestled with some major problems. And the fate of their district rode in the balance. The problems they faced were similar to those of other Colorado districts, compounded by their geographic isolation. Every mining district needed the best transportation system available, experienced investors combined with sound investment, and mineral reserves to develop. The San Juans offered the last in abundance. It was hoped the first two would appear. Railroads - much needed transportation link Nothing was more desired than railroad connections, the penultimate nineteenth century form of transportation. Colorado's own, the Denver & Rio Grande, resolved the issue with its mountain-hugging narrow gauge. As early as the mid-1870s, the D&RG dreamed of tapping this potentially lucrative market in southwestern Colorado. A national economic depression and then the Leadville silver excitement prevented immediate construction. Not until 1879-80 did survey crews start work.

Jan 2, 1988

By Cliff Holloway

The past year has been difficult for Canada's primary industries. The mining, oil and forestry industries have been hit by low prices and a reduced demand for natural resources. Foreign competition, militant environmentalists, the breakdown of the Asian and European economies and Canada's shrinking dollar have all put additional pressures on the commodity purchaser to buy smarter. It is easy to appreciate why operations and maintenance supervisors want the best performing product. It makes good sense. The challenge is to source that quality product while staying within the budget. The bottom line (price), however, often becomes the control- ling factor, usually at the expense of quality and performance. This is short-term thinking, often with expensive consequences.

Jan 1, 1999

By Faruk Oksuz, Dave Schiemann, Miguel Sanchez, Patrick Jensen

"The McCook Main Tunnel connects Chicago’s Tunnel and Reservoir Plan (TARP) Mainstream Tunnel to the McCook Reservoir. The tunnel system consists of a 10 m (33 ft) finished diameter and 490-m (1,600-ft) long hard-rock tunnel constructed from a 27.5-m (90-ft) diameter and 92 m (300 ft) deep main gate shaft. The gate shaft houses six high-head 4.4 x 9 m (14.5 x 29.5 ft) wheel gates installed in the bifurcated and steel-lined section of the tunnel. The tunnel also includes portal and energy dissipation structures as it daylights into the reservoir. Construction of the McCook Main Tunnel in live flow conditions was a challenging task for the McCook Main Tunnel Project participants, the project owner U.S. Army Corps of Engineers (USACE), local sponsor Metropolitan Water Reclamation District (MWRD) of Greater Chicago, designer Black & Veatch and contractor Kiewit Infrastructure Co. (Kiewit). Once completed in two stages in 2017 and 2029, the McCook Reservoir will hold 38 billion L (10 billion gal) of combined sewer overflows (CSO) and flood waters from the city of Chicago and 36 surrounding communities in Cook County, IL The construction of the tunnel system was divided into two contracts. The first contract for the gate and construction access shaft was completed in August 2011. The second contract included tunnel excavation and concrete and steel lining that was completed in September 2014; installation of gates and hydraulic cylinders that was completed in June 2017; and the last major construction activity was the removal of a temporary concrete plug (bulkhead) and lining that tunnel section to bring the overall tunnel and gates system online before Dec. 31, 2017.This article focuses on the installation, testing and commissioning of the high head wheel gates. Live tunnel connection details to TARP Mainstream Tunnel were addressed in a previous paper submitted at the World Tunneling Conference in 2016."

Mar 1, 2019

By Brian V. Roulston

Potash is Canada's leading industrial mineral in terms of value of production, with 11.1 M tonnes of muriate of potash produced in 1992 for a value in excess of $1 billion U.S. Each tonne of potash produced generates about 2 tonnes of waste salt, together with slimes and brine. The disposal of these waste products, particularly the salt and slimes which are discharged on the surface, has recently become an environmental concern. This concern is forcing companies and regulatory authorities to review disposal practices. In New Brunswick, on Canada's east coast, Potash Company of America operates a mine at which 2 M tonnes of potash ore and 0.5 M tonnes of rock salt are mined each year. The mine is situated in an environmentally sensitive area, noted for its dairy farming and salmon angling. In such an area it was recognized that the storage of waste on surface would be unacceptable, and the mine was designed around this principle. Three main waste streams - salt, slimes, and brine - must be managed as an integral part of the mining system. Around 1.5 M tonnes of fine salt tailings from the milling process and the rock salt screening operation, are sent directly to the active cut-and-fill potash stopes to be used as backfill. Slimes and excess brine from the mill are piped underground as a slurry to be discharged into one of the basin shaped stopes created by mining of the rock salt. While the slimes settle out, the clarified brine is withdrawn from part of the stope to be pumped to surface as a feedstock for the evaporator - a process which recovers the contained potash values in the brine. By designing a system which integrates the mining, processing and disposal of all product streams, and by careful production planning, it has been shown that zero effluent potash mining is possible and points the way for the industry in the future.

Jan 1, 1995

By José Mujica, Mónica Campos, María Fe Campos

The extraction and processing of metals and other minerals have played an important role in economic, political and social development worldwide, from the early stages of prehistory to the present day (Gosner, 2020). Mining has been a fundamental part of human civilization, providing the raw materials necessary for technological, infrastructure and industrial advances. As society progresses, the importance of mining continues to grow, supporting the development of everything from the smallest electronic devices to the tallest skyscrapers (Escamilla, 2024). The economy of a nation is connected to its extractive industries (Moreira and McMahon, 2014), which have seen dramatic growth in recent years (Pietrobelli et al., 2018). In a context of increasing demand for natural resources, driven by the development of emerging technologies, the expansion of infrastructure and the foundation of engineering achievements for the coming decades (Minerals Education Coalition, 2024), mining should focus efforts on global development, requiring a comprehensive approach to sustainability that addresses the planet’s needs and protects the well-being, primarily, of the communities and environments where mining operations take place (Figari, 2024). In these areas, diversity and inclusion should be promoted, thus fostering equitable and sustainable development. The sustainable development goals (SDGs), also known as the global goals, could serve as a key framework for fostering a strong social management culture in mining. The SDGs were adopted by the United Nations (UN) in 2015 as a universal call to end poverty, protect the planet, and ensure that all people enjoy peace and prosperity by 2030 (United Nations Development Programme, n.d.). Companies have compelling reasons to align their actions with the SDGs, as their long-term success depends on healthy communities. This is a major challenge that requires collaborative efforts (Singh and Rahman, 2021). As Fraser (2021) mentions, achieving more sustainable outcomes may involve mining companies and communities working together collaboratively. This article proposes an innovative approach: Inclusive mining for sustainable development, which aims not only to maximize economic profitability but also to promote social and environmental well-being by integrating the UN’s SDGs, primar)ily focused on diversity and inclusion. This can be achieved through the implementation of a key value-added initiative for mining companies: the creation and operation of a corporate volunteering program aimed at developing and executing inclusive practices to promote gender equality, the inclusion of local communities and indigenous peoples, and accessibility for people with disabilities. This proposal will educate employees and stakeholders about sustainability and promote concrete actions through corporate volunteering to strengthen the mining company’s commitment to community development, improve social relations and advance toward achieving the UN’s SDGs, establishing the company as a global change agent.

Nov 1, 2025

By C. J. Pritchard, R. D. Jacksha, K. V. Raj, C. B. Sunderman

In underground metal/nonmetal mines, repeated localized short-term exposure to high levels of airborne contaminants can become a serious health issue. Currently, there are no common mechanisms to control or mitigate these short-term high exposures to contaminants. To improve miners’ health and safety, the U.S. National Institute for Occupational Safety and Health’s Spokane Mining Research Division (SMRD) is developing a smart monitoring and control (SMAC) system for the real-time monitoring of mine air quality, with integrated countermeasures to reduce high concentrations of airborne contaminants in localized sections of mines. To develop and test a SMAC system capable of being implemented in an underground mine, SMRD researchers built a test apparatus incorporating a fan, louver, ducting and sensors combined with atmospheric monitoring and control software. This system will institute effective countermeasures to reduce contaminant levels, improving miner safety and health.

Jan 1, 2018

By Scott Burchmore, Jason Emery, Michael Melville

This paper presents best practice data management for monitoring of extensometers in Australian underground coal mines. This work is based on the combined experience of the authors and the available literature. The information and ideas presented herein are a culmination of many years of database development founded from mine site-based ground support design, underground inspections, extensometer data management and data analysis. Each author has more than ten years’ experience as a practicing geotechnical engineer at several operating industry wide research project focused on utilizing mechanical extensometer data for data analytics and machine learning. Principal hazard ground control management plans, stipulated in Australian coal mining legislation, outline the mandatory installation of ground monitoring devices during routine mining activities. After 20+ years of data gathering the barrier to implementing modern data analytics remains the challenges imposed by inconsistent data structure and data quality. This inconsistency is still routinely found between sites, companies and mining regions. Through the relatively simple application of a standardized database structure, the potential to shift from simplistic tracking of trigger levels, siloed at individual sites, to an industry standard method for compilation & comparison of monitoring data is enabled.

Jun 25, 2024

By Geno Saccomanno

INTRODUCTION Cancer of the lung in uranium miners has been reported by many authors. In fact, it has become a most popular subject for comment by environmentalists, health physicists, and newspaper writers. I believe it appropriate for me to discuss cancer of the lung in uranium miners in a general way commenting briefly on etiology, incidence, tumor cell types, and particularly, tumor development and treatment. Cytological development of cancer in its incipient stages, particularly the in situ stage, relates to potential cure with photoradiation, early diagnosis, and treatment. Our observations of the cytological response to this modality of diagnosis and treatment will be discussed briefly since this area will also be covered by Doctor Balchum. The cause of lung cancer in uranium miners is primarily due to two carcinogens; cigarette smoking and radon daughter radiation. Cigarette smoking has continued at the same intensity over time among uranium miners; about 60% of the miners are cigarette smokers and 40% are non-smokers. Radon daughter exposure to the uranium miner has varied from mine to mine, but over the last 20 years has been reduced to a minor fraction (.3 WL) of the level that prevailed in many of the mines during the 1950-1960 era when many of the miners were exposed to more than 10 WLM. Sputum samples have been examined on as many uranium miners as responded on the Colorado Plateau since 1956. Autopsy studies were done whenever this was permissible. In some instances, only tissue from a biopsy of a node or lung was available for study. Smoking histories were also taken. Approximately 200,000 sputum samples were examined and histological examinations of lung lesions were made from 312 cases. METHODS The method of sputum cytological collection and preparation was reported previously. I The lungs were fixed with formalin and prepared for sectioning by Dr. Oscar Auerbach with his block-section method. RESULTS Three-hundred-twelve lung cancers from uranium miners were examined. The tumor types and the age at death for each type, smokers and non-smokers, are given in Table #1. The incidence of the tumors in the smokers and non-smokers is given in Table #2. The incidence of small cell carcinoma of the lung has decreased from an incidence of 76% of all the lung cancers found in uranium miners to 22% of these lesions (Figure #1). The decrease in incidence of this tumor is probably due to decreased exposure to radiation in the mines.

Jan 1, 1981

By E. M. - Technical Papers Spokes

A.B. Rushton The work and resulting publications of the Committee on Underground Coal Mine Safety and The President's Commission on Coal were appropriate at the time of publication. The statistics cited in the publications appeared to be valid, and the actions proposed by the committee had merit. Although the actions proposed to achieve further improvements in safety may have been worthy of repeating, to associate statistics (Table 1) that are seven to eight years old with company names is bad. Statistics are readily available from the Mine Safety and Health Administration (MSHA) and are usually within three months of being up to date. A review of the most recent Coal Controlling Co. Report will reveal significant changes in the rankings. The more recent statistics should have been cited, or at least compared with those used in the article. Westmoreland Coal Co. is listed as having a 21.1 disabling injury rate for the period (1/78-12/80). The disabling injury rate for the Company for the year ending 1985 was 7.4 for the underground mines and 6.25 for the total facilities. Through March 1986, the dis- abling rate for the underground mines was 2.86. The management and employees of Westmoreland Coal Co. are committed to safety. The improvements achieved over the past five years attest to that commitment. We are justifiably proud of the achievement and dislike being misrepresented as in the April 1986 article Reply by E.M. Spokes I regret that the lapse of time since the original work gives a picture of safety practice that is no longer true today. That Westmoreland has reduced its disabling injury rate by 65% to 7.4 in 1985 is most commendable, and I congratulate you for this accomplishment. It is typical of the progress sought by the National Academy of Science and National Research Council when they funded the original study and published "Toward Safer Underground Coal Mines" in 1982. If a significant number of companies do as well as Westmoreland, the report will have served its purpose. Since the paper was primarily a condensation of the original report, it would not have been appropriate to seek access to later statistics. The purpose in seeking its publication at the time of presentation was to reach those who might have missed the original report. The fact that publication was delayed has not voided that purpose and may have reminded some who were aware of the original that its recommendations still apply to improvement of underground coal mine safety

Jan 1, 1987