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By G. Bourque

Early in the design stage of their new concentrator for the Mount Wright Plant, Quebec Cartier Mining decided to use a process computer for total control of crushing, grinding and concentrating. A map of the area is given in figure 1 and a view of the plant in figure 2. Although the use of process computers is not a new idea in petrochemical and chemical industries, their use in the mining industry is very limited. We innovated in using the computer, not only for data logging, as we have seen in some other plants, but a sole operator located in the administration building, starts and stops mill lines, crushers, load-out system, tailings, thickeners, etc ... by means of a CRT console. Our process is fairly simple as can be seen on the schematic process flow diagram (figure 3). .The ore, carried by 136t diesel electric trucks, is dumped through ore pockets onto two primary pan feeders. The feeders supply two 1,52mx2,79m gyratory crushers which reduce the ore to minus 20,32 cm. Each crushing line have a capacity of 5600t per hour and feed a shuttle conveyor distributing the crude ore into six silos.

Jan 1, 1979

By Arthur Matzick

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Jan 1, 1966

Entering June, U. S. producer pricing of 99.5 percent unalloyed aluminum ingot was divided at 53-57 cents per pound. The Kaiser Aluminum and Chemical Corp. took the initiative and raised its June 1 ingot values by 4 cents to 57 cents. Consolidated Aluminum Corp. announced plans to increase ingot prices by 4.5 cents per pound to 57.5 cents per pound effective May 15. Dealers increased their May ingot quotes by 1.5-2 cents to 50-50.5 cents. CADMIUM While producers in the United States kept May cadmium at $2.25-$2.50, dealers increased their quotes by 15-30 cents to as high as $2.15.

Jan 1, 1978

By Robert D. Pehlke

"The evolution of oxygen steelmaking is reviewed and new operating processes are described. The developments which could impact this technology are summarized. Staged and continuous steelmaking are considered in the light of new technologies. The future opportunities for oxygen steelmaking processes are overviewed. IntroductionThe use of oxygen in steelmaking was originally brought on the scene by the development of pneumatic steelmaking. Sir Henry Bessemer in England originally conceptualized the use of gaseous oxygen in steelmaking, and then he and William Kelly in Eddyville, Kentucky independently developed the original pneumatic process which involved blowing air through a bath of molten pig iron to oxidize the carbon and silicon and produce steel. This process and many following processes, including those which would use pure oxygen gas, have been proposed.Beginning with the first commercial oxygen steelmaking vessels at Linz, Austria in 1952, the world steelmaking industry has adopted this style of processing. In general, the process has involved the use of steel scrap in amounts from 20 to 35% of the metallic charge with molten pig iron produced in blast furnaces making up the remainder. The impurities in the charge are oxidized through the use of oxygen gas injected into the steelmaking vessel.However, currently being adopted into commerical practice and on the horizon are a number of advances in this process which include the use of iron ores as a source of iron and oxygen, the use of an all scrap charge, incorporation of pre-reduced iron, the use of auxillary fuels to change the balance of cold and liquid iron-base charge materials and numerous refining techniques."

Jan 1, 1988

By S. L. Weber, D. E. Banks

"Silicosis was first reported by the ancient Greeks and is apparently as old as human history. The prevalence of this illness peaked in the last half of the 19th century and the early part of this century, when mechanized industry was developing and the relationship between dust exposure and disease was less well understood. Yet, even today in devel-oped countries, sporadic outbreaks of silicosis occur when workers are consistently exposed to silica particles of respir-able size (0.5 to 5.0 µm in diameter) at levels exceeding those recognized to be safe.Silicon dioxide or silica. is the earth's most abundant mineral. Silica is considered to be either free (i.e.. unbound to other minerals) or combined. Minerals with high amounts of free silica include quartz (including granite) flint. Chert, opal, chalcedony, and diatomite. Combined forms of silica are called silicates and include, among others, asbestos talc and kaolin.In the crystalline form, silica exists as quartz, cristobalite, and tridymite (Fig. 28). Of these quartz is ubiquitous in the environment and occurs as sand and as a part of many rocks. Cristobalite and tridymite occur naturally in lava and can be formed by the heating of quartz or amorphous silica. Cristo-balite is more tibrogenic than quartz. Amorphous silica is noncrystalline and, therefore, is relatively nontoxic and does not cause silicosis. It occurs as diatomite (skeletons of pre-historic marine organisms) or as vitreous silica (glass), the result of carefully melting and then quickly cooling free crystalline silica. Heating diatomite with or without alkali (a process known as calcining), forms cristobalite and adds the respiratory toxicity of free crystalline silica.There are many opportunities for occupational exposure to respirable crystalline free silica. Some of the commonly en-countered occupations in which the risk of silicosis exists are reported in Table 20.Silicosis. the pulmonary disease caused by the inhalation of silica particles of respirable size, is most commonly cate-gorized by findings on the chest radiograph. The most typical presentations simple silicosis and progressive massive fibrosis appear different radiologically but are grouped under the category of classic silicosis because they are a part of the radiographic spectrum of this illness. Radiographically, simple silicosis appears as small (less than 10 mm in diameter), rounded opacities, typically predominant in the upper lung zones. Progressive massive fibrosis is the result of the coalescence of these small nodular opacities and appears as larger opacities (more than 10 mm in diameter), again typicallydistributed in the upper lung zones."

Dec 1, 1995

By P. Bissert, M. Klein, L. Yan, D. Yantek, R. Matetic

"U.S. Mine Safety and Health Administration (MSHA) regulations require underground coal mines to use refuge alternatives (RAs) to provide a breathable air environment for 96 hours. One of the main concerns with the use of mobile RAs is heat and humidity buildup inside the RA. The accumulation of heat and humidity can result in miners suffering heat stress or even death. MSHA regulations require that the apparent temperature in an occupied RA not exceed 95 °F. To investigate this, the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted testing on a 23-person tent-type RA in its Experimental Mine in a test area that was isolated from the mine ventilation system. The test results showed that the average measured air temperature within the RA increased by 9.4 °C (17 °F) and the relative humidity approached 94 percent at the end of a 96-hour test. The test results were used to benchmark a thermal simulation model of the tested RA. The validated thermal simulation model predicted the volume-weighted average air temperature inside the RA tent at the end of 96 hours to within 0.06 °C (0.1 °F) of the average measured air temperature. IntroductionIf an accident occurs in an underground coal mine, miners who fail to escape from the mine can enter a refuge alternative (RA) for protection from adverse conditions, such as high carbon monoxide levels. One of the main concerns with the use of mobile RAs is the potentially adverse thermal environment inside an RA from the metabolic heat of the occupants and the heat released by the carbon dioxide (CO2) scrubbing system. Moreover, the humidity within the RA will increase through occupants’ respiration and perspiration, and from the chemical reaction within the CO2 scrubbing system. The accumulation of heat and humidity can result in miners suffering heat stress, heat stroke or even death."

Sep 1, 2016

By David Scott, Denis V. Lachance, Daniel Marcotie

"LocationThe Heath Steele mine is located 50 km northwest of Miramichi, New Brunswick.Brief DescriptionHeath Steele is a 2700 t/d, copper-lead-zinc operation which employs conventional crushing, grinding, and differential flotation.HistoryThe Heath Steele mine is located in northeastern New Brunswick approximately 50 km northwest of the city of Miramichi and 65 km southwest of Bathurst. The massive sulphides containing ore values in zinc, lead, copper and silver were discovered in 1953 as a result of a joint venture between the American Metal Company and the International Nickel Company of Canada. The discovery was named after Mr. Heath Steele, manager of exploration for Amco at the time of the discovery.Mill production began in February 1957; however, the mine was forced to shutdown in 1958 due to depressed metal prices and metallurgical problems. It was re-opened in 1962 and milling operations resumed at 725 t/d until 1968 when the milling capacity was boosted to 1450 t/d and then to 2700 t/d in 1969.OreThe main ore zones are massive sulphides with very fine mineral grain. The chalcopyrite, galena and marmatitesphalerite occurrences are finely disseminated.Liberation is accomplished by grinding to 68% to 72% <400 mesh. Average mill feed assays are 0.8% to 1.2% copper, 1.8% to 2.5% lead, and 5.5% to 6.5% zinc, with 60 to 75 g/t silver."

Jan 1, 2000

By Deborah A. McCombe

"One of the cornerstones of NI43-101 Standards of Disclosure for Mineral Projects is the technical report. The purpose of the report is to provide a summary of the scientific and technical information concerning mineral exploration, development, and production activities on a mineral property that is material to an issuer. The reports must be prepared in accordance with NI43101 and Form 43-101F1 Technical Report and the information must be current as of the date of the filing of the technical report. As these reports provide important information to the investing public, qualified persons preparing these reports should, as much as possible, write in plain, simple language that can be easily read and understood by people who are not geoscientists or engineers. So let’s review some of the common deficiencies with technical reports. Non-current technical report Some of the factors you should consider when determining if your previously filed technical report is still current are as follows: •,Is there new technical information on the property, such as drilling, assays, metallurgical testwork? •,Have you made changes to key assumptions, parameters relating to mineral resources or mineral reserves, or economic analysis? If you have completed the previously recommended work, are your recommendations still current? Similarly, are your report recommendations consistent with what you are telling your shareholders or disclosing in the use of proceeds in your offering documents? For example, if the recommendations in the report consist of further exploration and metallurgical test-work prior to completing a preliminary feasibility study and you have completed the proposed work and are now raising money for a final feasibility study, the report is probably not current."

Jan 1, 2003

By H. C. Rolseth

The first step in the quarrying of granite, following removal of any overburden material, involves the freeing of large blocks from the formation. For many years the use of explosives was the accepted method of obtaining these blocks. Even today there are operations where this is considered to be the most economical method even though it does result in a high percentage of damaged stone. In more recent times the preferred procedure at most quarries has been to produce a continuous vertical cut or slot completely around the block to be separated. Originally, this was done by drilling a series of closely spaced holes around the block and breaking the web between the holes with a chisel-like tool known as a broaching bar. The machine used in this mechanical method of producing the relief slot is known as the channel bar. The modern day approach to the production of continuous channels was introduced to the industry around 1955 by the Linde Division of Union Carbide Corporation. The method employs a small rocket - jet burner producing a high temperature, high velocity exhaust flame which when directed against the granite causes it to disintegrate. This method, which has come to be known as "Jet Channeling", is now used by practically every major granite producer in the United States and Canada.

Jan 1, 1968

By R. G. Bottge

To better understand those factors which increase mining costs in Alaska, a Bureau of Mines study was conducted to compare the estimated costs of operating a 100,000-tpd open pit copper mine located on a hypothetical ore body in the Lake Clark area, Alaska, with the costs of mining a similarly sized hypothetical copper ore body near Tucson, Ariz. The information derived should be beneficial to the State and Federal governments in appraising the potential for development of large, low-grade porphyry copper deposits in south-central Alaska. Conventional mining and concentrating methods were assumed, and capital and operating costs were derived using flowsheets and standard costing methods. The total price required for copper mined in Alaska and Arizona was $1.12 and $0.63 per pound, respectively, plus or minus 20 percent. These values were obtained assuming no leaching of low-grade copper, recovery of gold, silver, and molybdenum as byproducts, 100-percent equity financing, and a 12 percent discounted cash flow rate of return. The average domestic and international prices for copper in July 1973 were $0.60 and $0.916 per pound, respectively. The existence of a developed transportation and power system in Alaska would have reduced capital and operating costs subs tantially. The required price for copper would have declined from $1.12 to $1.05 per pound, plus or minus 20 percent.

Jan 1, 1974

The Bougainville ore body was discovered in 1964 by a partnership of Conzinc Rio Tinto of Australia and New Broken Hill Consolidated Limited. The ore body is a porphyry copper in a fine-grained quartz diorite, which intrudes andesite volcanics and is located at an elevation of about 2, 000 ft in the Crown Prince Range of Bougainville in the Solomon Islands. Mineralization is predominantly chalcopyrite with some bornite and some gold and silver present. Rainfall in the area amounts to 200 in. (5. 08 m) per year. An active volcano is situated only 24 miles (38.4 km) from the mine, and all structures were designed to resist seismic shocks. An interesting and unique feature of the Bougainville operation was that the overburden was stripped with hydraulic monitors. Bougainville Copper, at 90,000 tpd, is the largest copper concentrator to be designed and constructed at one time; and besides the twin 54 in. by 74 in. Allis-Chalmers gyratories, it features seven 7 ft (2. 13 m) standard and fourteen 7 ft shorthead crushers, in addition to nine 18 ft diameter by 21 ft long (5. 5 m by 6. 4 m), 4250 hp, single -stage ball mills. During the design stage of the Bougainville primary crushing plant, several alternates were studied because the ore was expected to break with the production of large amounts of small-sized particles but with a minimum of fines. These alternates included two 54 in. by 74 in. gyratories with grizzlies, two 60 in. by 89 in. gyratories, and one 72 in. by 96 in. gyratory, the latter two installations without grizzlies. The two 54 in. units with grizzlies were finally selected as giving good reliability and the ability to handle the large amounts of small material in the feed. As originally installed, grizzly bars were set at 8 in. (203 mm); but, in an effort to perform more interparticle crushing in the primary and less rock-on-steel crushing in the secondaries and tertiaries, a test is underway (1976) to determine the effect of using 6 in. (152 mm) grizzly spacings (see write -up on Anaconda&apos;s crusher at Butte). The Bougainville ore is mined with 17 cu yd (13 cu m) shovels and hauled in 105, 170, and 210 st trucks to the crushers, which are equipped for two-side dumping. Up to 40% of the ore passes the grizzlies, which are equipped with splitters; and additional horizontal splitter bars are located directly above the spider caps. Because of the grizzlies, the crushers are supported by unique U-shaped enclosures, which are in turn supported by the end and center walls of the installation.

Jan 1, 1978

By Edward H. Robie

THE registration badges gave out, there were not enough programs, the Pioneer Hotel&apos;s rooms were insufficient, and some hundred applicants for banquet tickets had to be turned down at the Institute&apos;s Regional Meeting in Tucson, Nov. 1-5. Minor inconveniences these, however, occasioned by the fact that, optimistic as they are in Arizona, about half again as many partook of the week&apos;s activities as were expected. For this, the local program committee can be blamed-both the technical and social features were too attractive in quantity and quality. Seriously speaking, though, the Institute has probably never had a more successful Regional Meeting than this one. It being the first that has been held in Arizona in 22 years, no effort was spared to make it the distinctive gathering that it was.

Jan 1, 1938

By Claiborne C. Van Zandt

THE heavy postwar demand for Portland Cement has created shortages that are gradually being overcome by increases in plant capacity. In the post-war period, the Lone Star Cement Corp. has expanded several of its existing 15 plants and has built 2 new plants, now in operation, with a third new plant under construction in Brazil, of design somewhat different from that of the two preceding ones. The new domestic plants are located at Lone Star, Va., near Roanoke, and at Maryneal, Tex., near Sweetwater, and went into operation during 1951. Each plant is equipped with two rotary kilns and has an initial capacity of 1,500,000 bbl per year, or 6,000,000 sacks. The total cost of each plant was about $10,500,000, and on this basis $7.00 in 1951 money are required per bbl of annual capacity; at 376 lb per bbl, this corresponds to $37.00 per ton of output. The investment corresponds to approximately $80,000 per hourly-wage earner employed. The purpose of this paper is to describe the most interesting design features of the two new and almost identical Lone Star plants. Why the Dry Process Was Chosen The two new domestic Lone Star mills employ the dry process because: 1-The raw materials at both properties are particularly suitable and can be dried very, readily. 2-The Maryneal, Tex., plant does not have water available for slurry. 3-Very substantial kiln fuel savings can be obtained. 4-Dry raw grinding reduces ball and liner wear and- general maintenance, without any sacrifice in power. Operating costs to date have more than justified the choice of the dry process for these two plants. Raw Materials The chemical composition of Portland Cement raw material after crushing, grinding, and mixing, but before burning, is about as follows: [ ] sometimes tailings from an iron ore concentrating plant. Certain objectionable materials occur in raw mix: magnesia, limited in cement to 5 pct, in excessive amounts; alkalies, as sodium and potassium; phosphorous; and sulphur, generally present in coal and oil. The Roanoke raw, materials are dense limestone and shale. The Maryneal materials are soft limestone and a hard brittle clay that can be handled much like shale. Sand and iron ore are required in small quantities. General Plant Layout and Construction The two plants are so similar that one joint description will cover both, with such exceptions as will be especially indicated. The crushing plant is located in the quarry, and raw material is conveyed by belt to the storage building, where all materials are stored and handled. Fig. 1 identifies the various structures of the Roanoke plant. The large storage building is used for the storing and handling of all materials, including limestone, shale, sand, iron ore, coal, clinker, and gypsum. Directly adjoining the storage building is a structure under a similar arched roof, containing the raw and clinker grinding departments and the electrical substation. The discharge ends of kilns and coolers, and coal or gas burning equipment are also placed at one end of the mill building. The 340ft long kilns extend away from the main buildings to form the long leg of an L, at the end of which is the feeding and kiln dust collecting equipment, and the raw blending silos are conveniently located adjacent to the feed end of the kilns. The machine shop, storeroom, electrical shop, foremen&apos;s office, service rooms, and meeting hall are combined in one structure in the center of the plant, and the office and laboratory are close by. The cement silos and packhouse do not have to be tied directly into the manufacturing process and are therefore located at a point convenient to the railroad tracks.

Jan 1, 1952

By Thomas Hyatt, Brandon Phetteplace, Camilo Alvarez

A test pile program was undertaken at a project site in Ain Sukhna, Egypt for an import/export oil jetty. Two 1219 mm diameter open ended steel pipe piles were evaluated at two separate test locations. Each test pile was dynamically tested during initial drive utilizing a Pile Driving Analyzer (PDA). Restrike testing was also performed to evaluate the time dependent soil setup. One static compression test and one static tension test was performed at each test location. A correlation of the static and dynamic load test results was established to develop a driving criteria for the piling across the two kilometer project. The constructability benefits of shorter piles will be discussed in more detail, given that the pile lengths were shortened by 9 to 10 meters on average. Lastly, the use of a four pile linear layout to perform both compression and tension tests will be covered. INTRODUCTION With the increased number of Very Large Crude Carriers (VLCC) & Ultra Large Crude Carriers (ULCC) being used to transport oil products around the world, companies and/or nations are presented with the challenge of transferring these products to and from the carriers in deep water scenarios, typically 15 to 20 meter depths, to accommodate the vessels draft. One option for loading/unloading the oil products from a VLCC or ULCC would be to transfer to/from smaller vessels several miles offshore, whereas the most economical option is to unload directly to a pipeline via a berth/jetty platform near shore. These berth platforms must be designed to withstand multiple loading scenarios while these carriers are moored and transferring their products. The use of Large Diameter Open Ended Pipes (LDOEP) piles are a common foundation choice for this offshore application. One of the drawbacks of LDOEP piles, especially across a large project site, is that there can be extreme variability in the pile driving behavior. This can be caused by either a change in soil conditions or the performance of the soil plug. Due to this variability, it is important to verify throughout the duration of the project that the piling is being installed to the correct criteria as established during the load test program. A well designed driven pile load test program, preferably with the combination of Static Load Testing (SLT) and Pile Driving Analysis (PDA), should develop a driving criteria that can allow the contractor and owner to monitor any change in driving behavior.

Jan 1, 2019

By O. S. North

As recently as the late 1920&apos;s there Were few indications that a 15-million-dollar-a-year industry would ever grow out of the mineralogic curiosity vermiculite. Today, it is an important industrial commodity, used primarily as an insulating material and lightweight aggregate, but with a wide range of other applications. The quantity of crude vermiculite produced and used in the United States increased 14-fold in the 17 years between 1935 and 1951. The vermiculite minerals are of secondary origin, formed by hydrothermal alteration of an ultrabasic igneous rock, generally pyroxenite, or by alteration of phlogopite or biotite mica or possibly other similar minerals. According to different authorities, vermiculite may originate either by direct hydrothermel means, by the weathering of biotite or phlogopite, or by a combination of these two agencies. Vermiculites frequently occur at or near the contacts of an acid intrusive rock, especially a pegmatite dike, with a basic or ultrabasic country rock.

Jan 1, 1953

By W. R. K. Wu

This bulletin traces the development of high-pressure, coal and tar hydrogenation technology, based on an intensive review of the pertinent literature. The bulletin was written as a part of the Bureau of Mines research program on synthetic liquid fuels. It covers the history and economics of the process; the chemical aspect of hydrogenation of coal, tar, and middle oil; the engineering aspect of converting coal and tar to liquid fuels, principally gasoline; and the equipment for the process. The literature covered includes documents of the United States and British Governments, journals, and other publications. Bureau results in the hydrogenation field are also incorporated.

Jan 1, 1968

By Rick Frechette, Greg Nelson

"The 2018 Elko Roundtable was held at the Red Lion in Elko, NV on March 15, 2018. The gracious host was once again Knight Piésold. Attendance was robust with representatives from more than 14 mining properties across Nevada representing nine corporations. Total attendance was at its highest in almost a decade. A high level of interest was also gauged by the number of companies with multiple attendees.The topic of water in mining was clearly a factor in creating the large show of interest. In terms of industry trends that are tracked annually, this topic had been absent from the list for more than 10 years (Deloitte, 2018) but was squarely planted there this year. And deservedly so. Three attending companies are signatories of the International Council on Mining and Metals (ICMM) which espouses a firm stance on water stewardship (ICMM, 2017).How’s the water?It is reported that water scarcity affects more than 40 percent of the world’s population (Deloitte, 2018). Consumption of water in the United States, based on the last detailed census, entails only 1.5 percent usage by the mining industry. The largest users are reportedly thermoelectric power and irrigation, combining for more than 75 percent of the U.S. consumption. During the prior census period, water usage at mines was up dramatically (USGS, 2014).Mine water source usage is primarily a mix of ground water and saline or fresh surface water resources. Over the previous period, saline sources experienced the greatest percentage in growth as a mine water source, nearly doubling in use. Nevada ranks second as a state nationally in mine water consumption. California is the leader, and Nevada is immediately followed by Utah and Alaska (USGS, 2014).Water rights in Nevada and the ongoing litigation at the state level, particularly over the Humboldt River basin, have elevated the concern over the supply of water and have raised the interest regarding the topic of water across the mining industry as well as within other industries.The Elko Roundtable meeting began with a safety share and introductions, and included each attendee mentioned a water problem or solution that he or she would like to discuss during the day. An interesting list of subtopics was developed from this round robin and yielded the following most common themes:• Mine pit dewatering during operation and pit wall stability.• Draindown from tailings dams and heap leach pads and dealing with this at closure.• Post closure pit lakes, pit lake water quality and associated water rights."

Dec 1, 2018

A parametric study was conducted to establish the optimum operating conditions for the column flotation of fine coal. The parameters examined in this investigation included collector and frother dosages, feed solids content, and the volumetric flow rates of feed slurry, air and wash water. Despite the wide range of conditions studied the experimental data were found to fall along single grade-recovery curves, just below the maximum separation predicted by the release analysis technique. The deviation of the parametric test data from the release curve was attributed to the nonselective entrainment of mineral matter associated with poor froth washing. The operating point on the characteristic recovery-grade curve was found to be primarily determined by feed rate and aeration rate.

Jan 1, 1992

By A. Sobering, G. N. Carlson

"This paper describes the conversion of the grinding section of the W a bush Mines pelletizing plant from conventional wet, open-circuit trunnion overflow ball milling, with filtering, and bentonite mixing on a common conveyor belt, to dry, open-circuit, grate discharge grinding, with pug mill mixing of bentonite and water at individual mills.The test work and data on operating economies to justify the cost of conversion are given. It is too early, at the time of writing, to have complete operating confirmation, but data are available. A brief description of the original plant is included."

Jan 1, 1971

By Sheridan A. Glen

As the Federal government along with individual states continue to grapple with the job of refining a comprehensive energy policy, coal continually stands out as an energy source which heralds a combination of old and new capabilities like an energy planners prophecy, but which is plagued with serious environmental constraints. To determine what level of coal utilization is ultimately possible for states East of the Mississippi, whose high sulfur content coal presents the most paramount of challenges, one must consider product availability, via existing transportation modes, the developing industrial markets and the ability of coal to meet the challenge of becoming an environmentally acceptable fuel. Gasification is emerging as a form of utilization, which during the next twenty years stands a good chance of being able to meet the challenge of making coal an environmentally clean, easily transport-able and usable fuel. It can be argued that, of all the potential ways of utilizing high sulfur coal, coal gasification is perhaps the most expensive, the most financially risky and carries environmental liabilities of its own. Synthetic gas and oil markets will undeniably be a function of price and demand, which, for the purposes of this paper, I&apos;m assuming will begin to merge in the late 1980&apos;s and into the 1990&apos;s. This is also presuming that public utility commissions will allow favorable price structure ruling so that gasified coal products can be rolled into their respective rate base, much the same as synthetic natural gas from petroleum by-products are currently being priced. The comparative economic markets of coal to gas pro-duct have plenty of time to mature. There is an approximate twelve-year lead time needed to bring coal gasification plants on line which will be able to compete in the market place for natural gas and oil customers.

Jan 1, 1977