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By Nancy J. Wheatley

I. INTRODUCTION The Massachusetts Water Resources Authority (MWRA) is a regional water and sewerage authority which provides wholesale water and sewer services to the Metropolitan Boston area. The MWRA was created by the Massachusetts Legislature as an independent authority in 1985 following the filing of a lawsuit in federal court to correct the pollution of Boston Harbor resulting from inadequate and inadequately maintained sewerage facilities. Immediately upon its creation, the MWRA began to tackle treatment plant issues, including addressing the need for a secondary treatment plant, planning for ceasing ocean discharging of sludge, and making interim repairs to the existing, antiquated treatment plants. The MWRA's initial activities led to a court-ordered schedule for construction of a single new primary and secondary treatment facility, for development of sludge management plan focussed principally on reuse, and for completion of a short term program of repairs to existing facilities. Once a schedule for completing these activities had been negotiated, the U.S. Environmental Protection Agency (EPA), a plaintiff in the federal court case, asked that the MWRA take "responsibility" for controlling discharges from combined sewer overflows (CSOs) within its service area. Combined sewers (sewers in which both sanitary sewage and storm water runoff are carried in a single pipe) presently discharge over 10 billion gallons of untreated wastewater into Boston Harbor and its [ ]

Jan 1, 1991

By David E. Thompson, Wesley E. Stimpson

The Massachusetts Bay Transportation Authority (MBTA) Red Line Extension Northwest is currently in the early stages of construction. The 3.1 mile extension of the Red Line from the existing Harvard Square Station in Cambridge, Massachusetts to Alewife Brook Parkway in Cambridge, Massachusetts will include a large, near surface hard rock, rapid transit station chamber at Porter Square in Cambridge (Figure 1). [ ]

Jan 1, 1979

By A. Roper

Since the Toronto conference in May 2002, the International Council on Mining and Minerals (ICMM) has made progress on the road to sustainability. Fifteen of the world?s largest mining and metal producing companies and twenty-five associations have made a long term commitment to ICMM to improve the environmental and social sustainability of their activities. Sir Robert Wilson (Rio Tinto) assumed the chairmanship of ICMM in October 2002. By December 2002, the Council had approved a Strategic Vision and an operating plan for 2003. Both have been posted on the ICMM website (www.icmm.com). ICMM?s Operating Plan sets out three priority tasks: - Providing strategic leadership to achieve improved sustainable development performance in the mining, minerals and metals industry. - Contributing to international policy discussions on cross-cutting issues of importance to the industry, in collaboration with national and commodity associations. - Promoting dialogue and partnership with other organizations to catalyze sector?wide sustainability initiatives.

Jan 1, 2003

By Jim Weeks

In July 1986, the United Mine Workers of America (UMWA) asked Secretary of Labor William Brock to form an advisory committee to advise the Mine Safety and Health Administration (MSHA) on rules and regulations concerning the use of diesel powered equipment in underground coal mines. The request was made under the Mine Health and Safety Acts of 1969 and 1977. The union's principal concern was with the chronic and acute health effects of breathing diesel exhaust. In July 1988, the advisory committee recommended that MSHA promulgate a variety of health and safety regulations. It also concluded that diesel particulate matter should be considered carcinogenic (MSHA, 1988). Now, seven years later, there are nearly twice as many pieces of diesel powered equipment in underground coal mines. MSHA, however, has not promulgated a single regulation to govern the use of this equipment. MSHA must fulfill its public responsibility to protect the health of miners. Regulations that take account of the considerable body of knowledge concerning these health effects must be a top priority of the incoming assistant secretary of labor for MSHA.

Jan 1, 1993

By C. J. Kirkland

HISTORICAL BACKGROUND For two thousand years and more, we insular Britons have been grateful for the existence of the narrow strip of water which seperates us from mainland Europe. It has given us a sense of security against invaders, though it has been breached many times. The first recorded serious consideration of a fixed crossing of the English Channel was in around 1802, when it was suggested to Napoleon I. The motive was not entirely peacable and the British Navy, who saw themselves as defenders of our shores, were decidedly unenthusiastic. A whole series of imaginative schemes were proposed in the course of the nineteenth century, embracing viaducts, immersed tubes, artificial islands as resting places for the horses which were to draw carriages, as well as mechanically bored tunnels. The first Channel Tunnel Company was formed in 1872, and an application for permission to construct a tunnel was made to the British Parliament. A Colonel Beaumont, of the Corps of Royal Engineers designed and constructed a machine which, in around 1882, bored over a mile of tunnel out to sea from Britain which exists to this day.

Jan 1, 1987

By Richard W. Kimball, Richard F. Coon

This paper describes drill and blast excavation and groundwater control measures at the Lake Mead Intake No. 2 project. The construction includes a deep access shaft, intake shaft, surge chamber, forebay chamber, intake tunnel, 22 well shafts and East Tunnel. Grouting ahead of the excavation face was used extensively during shaft and tunnel construction. Lake Mead Intake No. 1 was constructed in the early 1970’s under less severe groundwater conditions and this work was delayed by ground conditions and water control problems. Excavations for Lake Mead Intake No. 2 must be completed in 23 months to meet SNWA’s water delivery schedule.

Jan 1, 1999

By Liu Cheng-si

Basing on a brief assessment of the conventional theory of ventilating air distribution, its methods of calculation and practical application, this paper makes an approach to the controllability of different aircourses of a ventilation network and further points out that it is possible for the positions of control to extent into the natural distribution subnetwork of the ventilation network, which was been long considered as a restricted zone. This important discovery makes the regulation of the ventilation system more flexible and diversified, thus attaining quantitative distribution of ventilating air as well as a cost benefit. Because it has been impossible to solve the problem mentioned above by conventional theory and its relevant methods of calculation, the author, based on applying graph theory on the structure, characteristics, and requirements of controllability of the ventilation network, presents a new controllable subgraph concept and the means for determining the rational quantity for control devices of the ventilation network. The solution of all the control alternatives and methods of obtaining all the parameters for the solution of various alternatives have been derived. The economic benefit and the optional positions of the control devices have also been approached. Specific calculation examples are a1 so included in this paper. Along with the conventional theory and its methods, it can be seen that the new theory presented makes a great change in the control aspects of the ventilation network, with the number of possible alternatives increasing in an astonishing manner. Among the alternatives, some may be safer, more economical or technologically superior than those obtained from conventional theory. Thus, the new theory may provide an immense improvement in the choice of a ventilation system.

Jan 1, 1987

By Eugene A. Lang, William R. Archibald

Early in 1972, Rocky Mountain Energy Company approached MARCONAFLO with a unique request for assistance. They controlled a series of scattered ore deposits in a remote section of Wyoming which had become increasingly valuable despite their relatively small size, great depth and low grade. At the time, MARCONAFLO was in the process of developing a tailings reclaim system which was based on the use of submersible capsules. It appeared that this basic concept might be adapted to slurry uranium ores and pump them to the surface through a bored hole. This presentation will review for you the development of this unique and potentially very important application of MARCONAFLO technology. This first slide (SLIDE 1) depicts the total mining concept envisioned by MARCONAFLO and Rocky Mountain Energy Company. A series of six self-contained mining units would be positioned through boreholes into the ore strata. An oscillating MARCONAJET would direct a high pressure jet stream into the orebody and put it into a slurry which would flow back to a slurry pump. The slurry would then be pumped to the surface and to a collection tank from which it would be transferred to processing. Both the MARCONAJET and the slurry pump would be actuated and controlled by means of a hydraulic power console mounted on the trailer behind the service tower. By means of a high pressure water pump also mounted on the trailer, return water from processing would be delivered to the MARCONAJET to slurry the ore. Tailings would be returned to a backfill unit for redepositing in the mined-out cavities. A drill rig would precede the mining, and it was estimated that this configuration would represent an optimum system for most effective equipment utilization.

Jan 1, 1976

By G. S. Brierley, R. D. Drake, J. E. Kelley, J. C. Kellogg

This case study embodies the problems of an underground project under current contracting practices. It will provide a realistic framework for a structured examination of the anatomy of a major complex underground project. Just as it will illustrate the frustrations of the parties to an underground contract, it will also provide a means to examine potential opportunities to provide a better way to develop underground space. Urban Transit Authority (UTA) had planned to expand their heavy rail underground transit system through an extension to an existing line. UTA lacked sufficient funding to guarantee the construction and operation of this planned extension. Venture Partner Associates (VPA) in conjunction with four major department stores entered into an agreement to create a major underground space for a commercial/recreational facility. The concept was to locate the facility adjacent to a planned station and beneath existing aboveground office facilities. This group was known as Commercial Development Corporation (CDC). UTA had reached an agreement with UMTA to provide 20 percent of the line and station costs. UTA then entered into an agreement with CDC to provide the needed additional funding for the station work in return for locating the station adjacent to the planned underground commercial/recreational complex. The agreement called for CDC to contribute 20 percent to the station cost to a maximum of $25 million plus a one percent contribution from commercial/recreational revenues for operating costs.

Jan 1, 1989

By Lothar Baumann, Wilhelm Knickmeyer

In mechanized roadheading predominantly two methods of rock breakage are applied at present: the cutting method by means of picks and the cutting/crushing method by means of roller cutters. Both systems meanwhile reached a high degree of technical development and consequently show very few possibilities of further improvement. While application of hard-metal picks is limited by rock hardness, the roller cutters require a high specific thrust, and, accordingly, heavy carrier systems. Roller-cutter equipped tunneling machines are therefore only cost-effective in hard-coal mining if the high investments for transport and assembly are justified by a corresponding length of road to be headed. The limit for acceptable cost-effectiveness is at present a minimum heading length of approximately 3 km. In order to improve the specific cutting performance of roller cutters by activation, Bergbau-Forschung carried out a research project sponsored by the Commission of the European Communities and the provincial government of

Jan 1, 1981

By Kevin R. Burns, William A. Depree, John J. Jansky

This paper presents some of the work associated with the reduction of employee exposure to diesel and blasting contaminants at an underground salt mine. The purpose of the paper is to outline the procedures recommended in resolving the problems associated with these contaminants. The first stage consists of a complete mine ventilation survey. The purpose of the survey is to identify any problems in the mine. The survey consists of air quality, air quality and ventilating pressure measurements taken throughout the mine. After completing the survey, the information is analyzed to identify problem areas and the possible causes. All available solutions to reduce the levels of contaminants are then explored and evaluated for feasibility. The PSU Mine Ventilation Simulator is then used to accurately simulate possible changes to the ventilation system. These ventilation projections are a useful tool to illustrate to the company and union personnel the possible benefits of various ventilation changes. This paper will illustrate the phases involved in making important and sometimes expensive ventilation decisions. Through the cooperative efforts of MSHA, company and union personnel, the levels of contaminants have been reduced by approximately 200 percent. As a result of these ventilation improvements, the company can now safely increase production approximately 25 percent.

Jan 1, 1987

By Debra C. Man, S. Thomas Freeman, F. Wiley Horne

INTRODUCTION The Metropolitan Water District of Southern California (Metropolitan) is the largest water wholesaler in southern California. Its service area spans the major urbanized portions of Ventura, Los Angeles, Orange, San Bernardino, Riverside and San Diego counties. More than 15 million people are serviced by Metropolitan through its 27 member agencies. The primary sources of Metropolitan's water supply are the Colorado River Aqueduct (CRA) and California's State Water Project (SWP). Currently, planning and design level studies are underway by Metropolitan to expand the water storage and conveyance systems within the service area for the purposes of providing increased efficiency and flexibility to manage limited water supplies, improving water quality, and increasing system reliability. The system reliability issue is particularly significant because the conveyance facilities from both the CRA and the SWP must cross the active San Andreas fault. This fault is considered to be the source fault for the anticipated "Big Earthquake" in southern California. To meet these objectives, Metropolitan's expansion plans involve a major new storage reservoir, new large diameter pipeline and tunnel conveyance facilities, more efficient utilization of existing groundwater basins, and an aggressive public awareness and conservation program. This paper focuses on the planning studies that have been carried out for over 50 miles of tunnels being considered for several of Metropolitan's proposed conveyance systems. These tunnels have ranged in length from a few hundred feet to over 42,000 feet, with depths of cover ranging from a few tens of feet to over 3,000 feet, and finished diameters ranging from 10 to 20 feet.

Jan 1, 1993

By T. M. Gurr

It is estimated that in excess of one-half million chemicals are used throughout the American workplace. Hundreds of new chemicals are also being introduced into the workplace annually. Exposure to some of these chemicals can be harmful to workers and to the environment. The Occupational Safety and Health Administration (OSHA) estimates that approximately 25% of the U. S. labor force or approximately 25 million workers are exposed to one or more chemical hazards each year. OSHA has determined that this poses a serious problem for workers exposed to such chemicals. Chemical exposure may cause safety and health problems. Health problems can include a cause or contribution to heart ailments, kidney and lung damage, sterility, cancer, burns, and rashes. Safety hazards can include the potential to cause fires and explosions and other serious accidents.

Jan 1, 1989

By L. A. Ruth

Introduction The US Department of Energy's Office of Fossil Energy has begun a new approach for developing the ultra-clean energy plants. This approach will allow the nation to continue to use low-cost fossil fuel feedstocks during the early decades of the 21st century. The new approach is called Vision 21. The overall goal is to effectively eliminate, at competitive costs, environmental concerns associated with the use of fossil fuels for producing electricity and transportation fuels. Vision 21 is based on the following three premises: •The nation will need to rely on fossil fuels for a major share of our energy needs well into the 21st century. •It makes good sense to rely on a diverse mix of energy resources, including coal, gas,

Jan 1, 2003

By H. V. Scotland

Lafarge Corporation's Texas Quarry, in Baltimore MD, achieved a substantial expansion of pit reserves by removing an inactive underground mine. The daylighting program, designed, and completed in 1997, open pit mined more than400 meters of room and pillar workings which were originally developed to recover high brightness Calcium Carbonate. The project proved to be a challenge throughout its course as the pit plan was modified and successful daylighting techniques were developed to remove the mine without adversely affecting the safety of the operation, quality of the stone recovered, or negatively impacting the surrounding community. The design parameters and techniques developed and implemented at Texas may prove of interest to other operators as they are faced with daylighting opportunities. This article will detail the challenges we faced and the solutions which made the project a success.

Jan 1, 1999

By Erich U. Petersen

Harbuck et al. (1990) present results of research on sulfuric acid leaching of a germanium-gallium ore and shed considerable insight on possible extraction methods for gallium and germanium. However, the presentation does not give sufficient details to evaluate the research, so some of the conclusions may not be as applicable as stated. The objective of this communi¬cation is to indicate that relevant and easily obtainable geological and technical information was omitted. Consequently, on this basis, alternative explanations for some of the data are possible. Discussed below are the omission of: • pertinent geological, mineralogical and geochemical literature; • details regarding the determination of germanium concentration in quartz by electron microprobe; and • details on the calculation of the amount of germanium locked in quartz.

Jan 1, 1992

By Mark L. Mott, Michael P. Synder

The Mine Safety and Health Administration has developed a program to improve the decision making process of personnel involved in mine emergency situations. The Mine Emergency Responsiveness Development Program (MERD) has been designed specifically for fires and explosions in underground mines. This program addresses the responsibilities and organizational requirements that are necessary during rescue and recovery operations of a mine emergency . Specific skills and knowledge are required to manage an organization of personnel under conditions of intense stress, such as a mine fire or explosion. As a result, the MERD program develops these skills by providing role playing emergency simulations. This role playing provides the participants with the opportunity to experience problems, explore solutions and interact with other personalities which may exist during mine emergency situations. This paper presents the standard procedures for the MERD program developed by the Ventilation Division of the Pittsburgh Health Technology Center.

Jan 1, 1991

By J. N. Philbrook

As with most industries, mining must now include in its plan of operation mechanisms to address a project's environmental impact. New regulations have focused attention on the potential environmental impacts of industry, particularly the handling of wastes. Modifications are currently being proposed to the Bevill Amendment. And development is ongoing of Resource Conservation and Recovery Act (RCRA) Subtitle D regulations specific to mining wastes. The result is a growing concern on the part of lenders, developers, buyers and owners regarding acquisition and ownership of mining properties. One of the most effective tools in managing the regulatory requirements is an environmental audit. An environmental audit can be a literature review to determine regulatory requirements. The audit can also take on the form of a phase-one site assessment. This is a limited investigation to determine whether there are specific

Jan 1, 1991

By Z. Eisenstein, H. K. Heinz, F. M. Kuwajima

Due to its complex rheological behaviour, shotcrete induces a ground-structure interaction that differs significantly from other types of tunnel linings. For the same reason, the instrumentation of shotcrete linings presents special problems, particularly when it comes to estimating the stresses transferred to the lining during construction. The shotcrete characteristics which affect the stress distribution are initially discussed. Measurements obtained in a recent soft ground tunnel are also presented. The conclusions are aimed at introducing practical recommendations for the design of tunnels where shotcrete is used as initial and/or final support.

Jan 1, 1991

By P. van der Veen

There are two key reasons for this presentation: - Sustainability - Improving the economic, environmental and social impact of mining. As I will discuss in my presentation we see sustainability throughout the mine life cycle as critical for successful mine development - that is the mine makes a successful contribution to economic development and poverty alleviation for the host community and host country and at the same time the mine is a successful investment for the investor. - Knowledge Sharing ? The World Bank is not only a development bank, but also a ?knowledge bank?. One of our key functions is the dissemination of usable information and knowledge. We are here not only to share our experience but to learn from your experience as well ? two reasons that fit clearly with the mandate of the World Bank Group.

Jan 1, 2003