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By J. L. Floyd

The Trapper Mine is a large surface coal operation located in northwestern Colorado US. The coal seams at the mine dip an average of 8 degrees so, historically, their dragline pits have been orien-tated parallel to the dip of the coal seam to balance stripping ratios. However, the mine plan in the future G and Z pits is designed to take advantage of pit orientations that are parallel to the strike of the coal. During the initial presplit and cast blasts in G pit, significant slope damage occurred. This damage included the opening of joints and tension cracking. There was also block movement directly above the L coal seam, which is the main plane of weakness in the slope. A detailed site evaluation was conducted to develop specific blast design modifications to protect the slopes during future blasting. The modified de-signs successfully controlled vibration levels during the blasting of the Z pit box cut. This paper includes a review of the blast vibration related factors that influence slope stability along with a detailed discussion of the field tests and design modifications developed.

Jan 1, 2004

By Samuel Tescher

The operation of gaseous mines is a problem, due to the fact that we have not only the ordinary mine accidents to guard against, but have also the ever present menace of a mine disaster involving a large number of human lives, and the destruction of valuable property. In looking over the reports of mine disasters throughout the country in the past several years, we find that methane gas, coming in contact with an ignition agency of some kind, has been the source of at least 75 per cent of our mine explosions. Coal dust, of course, plays its part in propagating the explosive action throughout the mine workings and rendering it more violent and destructive; nevertheless, the initial ignition of a body of explosive gas-sometimes of very small volume-has been the primer for the large majority of our mine disasters. We find also, that the places of initial ignition are most frequently found at the working faces, or in close proximity thereto. This is mainly due to the following reasons: First-The working faces are, as a rule, the places where methane gas is most freely generated. Second: They are places that are most poorly ventilated. Third-They are the places where ignition agencies are most frequently found. The sources of ignition, as a rule, consist of naked lights, the shooting -of shots, defective flame safety lamps, and electrical arcs. The problem, then, in the operation of gaseous mines, is primarily to so ventilate the working faces that an explosive mixture is not likely to occur, and to endeavor to keep away from the working faces all sources of ignition. To do both of these things may seem impossible. Nevertheless, by working along both of these directions, a great many disasters can be avoided. The efficient ventilation of the working faces is paramount. By efficient ventilation, we mean the continuous passing of large volumes of air at the working faces. This can only be accomplished by adequate ventilating equipment, capable of being driven by at least two independent and distinct sources of power, together with large, clean, straight air courses which are free of short turns, constructed areas, and leaky doors and stoppings. In other words, furnish a suitable course for its travel through the mine. Many of us sharpen our pencils and rack our brains to properly estimate the proper size pump and pipe equipment that may be needed to handle a certain amount of water. We estimate the size of copper conductors to a nicety. We immediately rush to repair leaks in our water, compressed air or electric lines. But how many of us give serious thought to the travel of the air through our mines, the health and safety-giving fluid on which so much depends! In driving air courses, a certain economical cross-sectional area should be adopted and maintained as standard. When turns are necessary, they should be made with long radius curves, and the cross-sectional area should be increased on the curves. All entry stoppings should preferably be built of monolithic concrete, with suitable hitches into floor and ribs, and after the concrete has set, they should be examined and leaks due to shrinkage and settling should be eliminated. Overcasts and their approaches should have cross-sectional areas larger than the entries leading to them, to allow for the sudden change of direction, bearing in mind that air wants to travel in straight lines. In the early development of a property, ample provision should be made in the size of the main entry pillars to allow for the driving of additional

Jan 1, 1925

PRESIDENT WHITESIDE: I am sure we are very grateful indeed for this very interesting talk that Mr. McClure has given us. If anyone has any questions to ask Mr. McClure I am sure he will be glad to answer them at this time. MR. WEITZEL: I want to ask Mr. McClure whether in the instance he described by-passing the drier, whether there was any rest period between the crusher and the furnace, whether the powdered coal that was not dry was allowed to rest in the pipe or was blown directly into combustion chambers. MR. McCLURE: Yes, it moved directly; there might have been some difference had we given it an opportunity to rest. We just had to get in and get out so as not to interfere with operations. MR. WEITZEL: Your idea is, even though you did use a high moisture lignite, you could store it under water if you eliminated surface moisture later. That is a new idea to me; I always had thought that you had to reduce the moisture down under 2 per cent, and to try to store it with anything more than that, any higher moisture, you would have to break the stuff loose again, as it gets so hard it won't move. MR. McCLURE: It might develop I am absolutely wrong; I am just saying what I observed, and I may have had some unusual condition, which I did not detect; something may actually develop which will make my statement of drying lignite entirely wrong. It was quite a surprise to me, surprise to every-

Jan 1, 1923

The 65th Regular Meeting of the Rocky Mountain Coal Mining Institute convened at the Stanley Hotel, Estes Park, Colorado, and was in session at 10:00 a.m. The first session was called to order by Past President Joe T. Taylor, Kaiser Steel Corporation, Palo Alto, California. Manager of the Stanley Hotel, who welcomed the guests to the Stanley. After a few remarks, he introduced Bob Dean, for- mer Manager of the Stanley Hotel and again associated with the Stanley, who also made a welcoming talk as Mr. Dean has hosted the Institute at the Colorado Hotel in Glenwood Springs and in Estes Park. Mr. Taylor introduced President Stanley C. Shubart, Secretary-Treasurer, Schloss & Shubart, Inc., Denver, Colorado. Stan was raised in the machinery end of the coal industry following the footsteps of his Dad who was one of the founders of the RMCMI in 1912. And following his Dad's years of service to the Institute, 12 of them as Secretary, Stan has been active as Chairman of the Hotel & Registration Committee for 16 years, and, prior to his election as President, was General Chair- man for two years He is a graduate of the University of Colorado with a degree in mechanical engineering. He served our country in World War II and retired as a Colonel, Army Ordnance, after 43 years in the Reserve. He is a Trustee of National Jewish Hospital and was their President for 3 years. He has been active in many Military and professional societies, and in civic projects. I give you our President, Stan Shubart, for his remarks.

Jan 1, 1969

PRESIDENT LITTLEJOHN: We have with us a gentleman from Utah, who is familiarly known -as the "Mudite King," Mr. Reid, of the Lion Coal Company. Here is a letter I would like to read, and probably Mr. Reid will give us an idea of his Mudite machine, or the results he is obtaining. This question was brought up in Rock Springs, Wyoming, but Mr. Reid was not there personally during the discussion, but Mr. Burnell, who is general superintendent of the Lion Coal Com¬pany, as much as he possibly could, described the system and its effects. I believe Mr. Reid will probably be able to give a somewhat clearer statement this afternoon. This letter is from the Coal Mining Inspector of the State of Utah, John Crawford. "February 10, 1925. "The Industrial Commission of Utah, Building. "Statement of John Crawford, Coal Mine Inspector, in regard to Muditing in Coal Mines: "That Muditing used in connection with our present sprinkling system in coal mines is the missing link to the system we have had heretofore, because the water applied by the former system began to dry out, in heavy air currents, the moment it was put on. Consequently the dust that had been humidified by sprinkling, came back to its natural condition, and if anything, the combustible parts of it, in my opinion, were more intensified than previous to being wetted down. "The advantages that Muditing has over the old system of sprinkling are: "1st. The dust that is on the roof, timbers and sides of the entry is washed completely off and rolled up in the Mudite solution which entirely destroys the wings, crudely speaking, of the fine coal dust. "2nd. Sprinkling with the Mudite system, the water and mud is of greater extent than could be applied with a hand hose by a sprinkler. This sprinkling can be done while the mine is in operation, just the same as if water alone was being used. "3rd. The Mudite solution, when dried out, leaves a coating which serves as an armour to the coal, so that in the event of a local explosion, the inflammable matter on the coal is non-combustible; whereas, if that same coal had been sprinkled with water only, and made free of dust, the heat would have the same effect on the coal as it has on a stove when coal is thrown into it-instantaneous combustion. "Therefore, it is my opinion that the Mudite system is the missing link to the perfecting of our sprinkling system here in Utah. "(Signed) JOHN CRAWFORD." Mr. Reid has with him a few sam¬ples of his Mudite, after it has become solidified, taken from the floor, as I understand it. It is interesting. We have a few minutes to spare to good advantage, were we to ask Mr. Reid to give us an idea of his machine, as briefly as he possibly can, and also what he thinks the effect of the Mudite is compared to dry rock dust. Mr. Reid. (Applause.) MR. W. J. REID (Lion Coal Company) : I came down here with no intention of making any talk on Mudite. However, there being so many people that have seen Mudite at Wattis

Jan 1, 1925

[Addison, Herbert Big Horn Colleries Co., Colo. Bldg., Denver, Colo. Aleshire, N. C c-o Roberts & Schaefer Co., Wrigley Bldg., Chicago, Ill. Alexander, John Dacona, Colo. Allan, David Lafayette, Colo. Allen, John Ludlow, Colo. Allen, Thomas Box 420, Glenwood Springs, Colo. Alley, Gerald C. F. &I. Co., Pueblo, Colo. Allison, ArchieBox 562, Walsenburg, Colo. Allison, D. S 1331 Roberta St., Salt Lake City, Utah Allison, Park Engineer, Standard Coal Co., Standardville, Utah Allonier, Howard R c-o Lunkenheimer Co., Cincinnati, Ohio Ambler, J. B c-o Ambler & Riter, Kearns Bldg., Salt Lake City, Utah Anderson, A. E 403 Ideal Bldg., Denver, Colo. Andrews, Sam 503 Pike Ave., Canon City, Colo.. Angster, Joe Walsen, Colo. Angus, William B. W. Snodgrass, 1575 Lafayette St., Denver, Colo. Apperson, A. B Tramway Bldg., Denver, Colo. Armstrong, C. D Apperson Vallery Co., Tramway Bldg., Denver, Colo. Arnoldi,, Victor Ideal, Colo. Autrey, J. S Perrenaud Apts., Denver, Colo. Bachman, W. H 1601 Alcott St., Denver, Colo. Bailey, R. E Utah Power & Lt. Co., Kearns Bldg., Salt Lake City, Utah Baird, Elmer A Equitable Bldg., Denver, Colo. Bartlett, G. F 311 Ernest & Cranmer Bldg., Denver, Colo. Baxter, John M 3748 Lafayette St., Denver, Colo. Becker, J. A Box 682, Rock Springs, Wyo. Beebe, John. D 1414 Court Place, Denver, Colo. Bennett, F. C Colorado Fuel & Iron Co., Berwind, Colo. Benson, Geo Cumberland, Wyo. Betcher, B. L Standardville, Utah Beuchat, Charles Pryor, Colo. Bevan,John 1625 North Corona St., Colorado Springs, Colo. Bisch, James L Van Houten, N., M. Boissier, A. H. C Boston Bldg., Denver, Colo. Bottomley, Edward Kleenburn, Wyo. Bowen, James V Union Coal & Coke Co., Colorado Bldg., Denver, Colo. Bowie, Alex R Bowie, Colo. Bowie, John S Bowie, Colo. Bowie, Wallace D Bowie, Colo. Bowns, W. J Castle Gate, Utah Boyer, F. E 631Jackson St., Denver, Colo. Boyle, Chas Sweetwater, Wyo. Brandenburger, L 59 W. Broadway, Salt Lake City, Utah Brennan, W. D Dawson, N. M. Brewster, Burt B Walker Bank Bldg., Salt Lake City, Utah Brockman, A. L Sugarite, N. M. Brooks, Ed 513 Second St., No. 1 Hill, Rock Springs, Wyo. Brown, Geo. A Cumberland, Wyo. Brown, L. E :.1212 Walker Bldg., Salt Lake City, Utah Brown, Mark Y 629 East Main St., Trinidad, Colo. Bubb, H. H Cokedale, Colo. . Bullock, W. H 1052 Gas & Electric Bldg., Denver, Colo. Bunning, P. C Rock Springs, Wyo. Burnite, Thomas B 523 Boston Bldg., Denver, Colo. Butler, T. H Hanna, Wyo.]

Jan 1, 1924

Pictured on these pages are the eight RMCMI Scholarship Award Winners for the 1990-1991 year followed by a brief profile. All winners, except John Nixon from Texas, were present as guests of the Institute at the June convention in Keystone, Colorado to receive recognition at the Welcome Session Monday, July 1, 1991. Each state vice president served as the host for the collegiate winner. In addition to receiving a plaque from the Scholarship Chairman, Dr. Donald Gentry, each winner receives $750 tuition credit for the coming academic year. As this is a continuing award, the winners from the previous year will receive another $750 for tuition credit in their senior year if they have maintained good academic standing and are recommended by their university. Criteria for these awards to be made in the spring annually is (1) That the award be made to a sophomore student and used as tuition during the junior year. (2) That the recipient be both a U.S. citizen and a resident of the state involved. (3) That the recipient have good academic standing, be pursuing a degree in a mining related field and have an expressed interest in Western coal as a possible career path. The scholarship program includes curricula other than those in the mining departments, but in the engineering disciplines, such as geology, mineral processing and metallurgy. Contributions to this worthy project are tax deductible to each individual RMCMI member or his firm. Through annual donations of $100 or more, the Patrons of the Institute fund the scholarship program and the various vice presidents contribute the travel expenses to conventions for these outstanding young collegiates. Donations to this worthwhile program may be made payable to RMCMI Scholar- ship and mailed to the RMCMI Office, 3000 Youngfield Street, Suite 324, Lakewood, CO 80215. Profiles of the 1991 Scholarship Winners follow. [ ] Walter Mengel III University of Arizona Tucson, Arizona Walter has attended the Mining Engineering program at University of Arizona since fall, 1990. He is a very diligent student and has recently been selected student mine foreman for the San Xavier Mine. Walter is secretary of the U. of A. AIME Student Chapter and a student member of the AIME Tucson Chapter. His career interests lean towards western coal mining. [ ] Matthew Madden Colorado School of Mines Golden, CO Matt carries a 2.619 cumulative grade point average in the Mining Engineering Department and ranks 194 in a class of 440. He is involved in a number of school activites such as a member of the Society for Mining, Metallurgy and Exploration, Inc., member of the Resident Hall Association, a Admissions Ambassador, and will be a Resident Hall Director for 1991-1992. Matt is also involved in wrestling and received a Colorado School of Mines Athletic Scholarship in 1990.

Jan 1, 1991

By D. C. McClure

MR. McCLURE: Mr. Chairman, you sprang a surprise on me; I really came over here for a good time. Gentlemen, I am not at all qualified to pose as an expert on pulverized fuel; I have merely been making some rather interesting observations, and unfortunately at the present time, a great deal of substantial data, the technical data, I don't happen to have with me; it is still in the process of being calculated, but I will be very glad to tell you some of the observations as I have made them, and in as truthful and complete a way as I can. The question of how we would handle fuel became a very pressing subject in this new Valmont electric plant, which is now under progress. We have studied the methods of burning fuel for a number of years on different types of stokers at the existing plants in Denver; we are burning it with a natural draft chain grate and with underfeed and with forced draft chain grates, and I am very frank to confess at the present time that I have no answer as far as stokers are concerned for a better solution of the problem of burning lignite. In other words, I could not tell you that this or that is a better type of stoker to use for that coal. However, to boil the thing down, after considerable trials, the underfed stoker was chosen as the one most adaptable for the utilizing of lignite fuel if stokers are to be used. In other words, the chain grate was put aside. I might say in support of the chain grate, the prime reason for which that type of stoker was condemned, as far as lignite goes, is the initial investment charge and the large maintenance which is involved.

Jan 1, 1923

SECRETARY SHUBART: This letter will not surprise you. (Reads) UNITED STATES DEPARTMENT OF COMMERCE Bureau of Mines Washington Sept. 4, 192G. Benedict Shubart, Secy, Rocky Mountain Coal Mining Institute. Denver, Colo. Dear Sir: "Sorry not to be able to be with you but since my function in the Institute has been largely along the line of `stirrer up of trouble' (of course always with the aid of Dalrymple), I do not wish to fall from grace now so am sending you a pamphlet on the last page of which is a' tabulation as to accident indices of various coal mining states and it seems to indicate that the states comprising the Rocky Mountain Institute have the poorest accident record of all the states producing coal. "It seems to me that even allowing for possible deficiencies in connection with placing accidents upon basis of hours of exposure, our western states need to `tighten up' as to safety practices, hence I hope that the Safety Committee report will be both drastic and progressive and that western coal mines apply the drastic proposals in addition to approving them as the policy of the Institute. Why wouldn't it be advisable to have a committee appointed to ascertain why the safety record of the states comprising the Institute is so bad as to coal mines? Wishing the Institute all kinds of success." (Signed) D. HARRINGTON. SECRETARY SHUBART: He encloses this pamphlet issued by the Bureau of Mines. On the back of it is this table; and it is a fact that the Rocky Mountain States are down at the lowest in almost every case, at the lowest point, with the highest accident rate in almost every kind of accident. Maybe he is wrong; maybe he states this for reasons. That is a rotten looking table for us.

Jan 1, 1926

T. T. READ, BUREAU OF MINES: Mr. McAuliffe has asked a very practical question. Expressed in another way, the question is: If we have decided to use rock dust to prevent coal dust from exploding, have we got to take rock, that is, solid material,, break it up and finally grind it into dust (and fine grinding is very expensive), or can we take material that is already in a pretty fine state of subdivision and thereby save the expense of pulverizing it? Most of the preceding discussion has been from the view-point of practical experience, and I should like to suggest that we have not had enough practical experience in rock dusting to be able to answer this question, from the viewpoint of experience, with the degree of definiteness that Mr. McAuliffe desires. With your permission I will discuss the matter briefly from the theoretical standpoint, because after all the theoretical considerations, insofar as we understand them correctly, will apply to every' case, whereas in coming to a decision on this matter it will be necessary to take into consideration local conditions, which will necessarily vary in every case. Considering the matter in a rather elementary way, the first point is: What makes coal dust explode? The air of this room is full of dust at the present moment, even though we do not notice it. If you were to close up the room for a week, enough dust would settle on the floor so you could write your name on it. Of course, the dust which is in the air of this room is not coal dust but even if it were coal dust and you were to bring an open light in' here we all know that the dust would not explode. The reason for that is that the dust particles are not close enough together for the flame to propagate itself from one to the next. You will probably be able to see in the demonstration in the gallery on Saturday that the coal dust explosion is practically a very rapid burning of the dust. When you light one piece of dust it burns and gives out heat and if there is another piece of dust close enough to it so that the heat from the first piece is able to bring a second piece up to the burning temperature, then the flame will propagate itself through the mixture. But, if the particles are so far apart in the air that the' heat from one particle is dissipated before it reaches an adjoining one, and is therefore not able to bring the second particle up to the burning temperature, then the flame will not propagate. To get a coal dust explosion, it is not sufficient to have coal dust suspended in the air. The coal dust particles must be close enough together in the air so that the heat from one burning particle is able to heat the adjoining particles up to the point at which they will burn. There has been some discussion of the size of dust particles that will cause an explosion to propagate, and it has been pointed out that the minus 200-mesh dust is the most dangerous, and that particles coarser than 20-mesh will not propagate an explosion. There are two reasons for that. A large particle has very much smaller surface in proportion to its weight than a small particle has. You know the old story about the Indian who when asked how he could go around in cold weather without any clothes on said that an Indian was all face. A 200-mesh particle is almost all surface and there= fore is able to burn almost instantaneously, which means that it gives out its heat almost instantaneously, whereas a large particle with less surface in proportion to its weight burns more slowly, gives out its heat more slowly, and the heat has more time to be dissipated. The second reason why coarse dust does not easily propagate a flame is because it is so hard to make it

Jan 1, 1924

CHAIR: I see a great many safety men in the audience and I hope you will all take part in using up the time that we have left. The point brought up by all was the necessity of education. It is very hard to know just how this is going to be done. We get very little encouragement to do this. At a recent meeting at Rock Springs, 100 in attendance, and most of them mine officials. Another condition which contributes to accidents is the labor turnover in many of our States. With many companies I am told from actual statistics the labor turnover is 125 per cent. Each field has different mining conditions so that men coming from one field are not always familiar with the mine conditions in the field they come to. These are conditions which have to be overcome. WM. LITTLEJOHN: Mr. Harrington brought up the subject of sprinkling. I will try to tell what we are doing at the Utah Fuel Company camps. Our dust at Castle Gate is the most inflammable gas that has yet been tested at the Pittsburgh station of the Bureau of Mines, so it is up to us to use every precaution to keep it down. I will try to tell what we are doing regarding sprinkling from tanks. We now have in operation two tanks in our locomotive roads, one in Castle Gate, one in Sunnyside. These tanks are something like 500-gallon tanks with pump on one end of truck which gets its power from the power wire and has a half circle perforated pipe on the other end of tank. This is simply hooked on to the locomotive. When the pump is started up it throws a fine spray of water all around which wets the roof, the sides and floor. We found this very successful from an economical as well as a working standpoint. A roadway that we probably would have had to pay a man at least two shifts for, covering the full distance, with the ordinary hose and spray, we can do in half a day and do it more thoroughly. We are also figuring on at the present time using the same system on rope haulage ways, which of course will have to be run by a reel from the feed lines, handling say four hundred feet each way before reconnecting. We haven't got it finished, but are working on it at the present time. MR. COLBURN: I would like to say a few words -about this question of education. Education was mentioned by all three sections of the Safety Committee. Education regarding safety might be divided into two branches. One branch is for the official at the mine to keep him acquainted with the latest developments in safety equipment and safety methods. The other part of education is for the workmen. The United States Bureau of Mines is co-operating in both directions. Safety Clubs are organized around the Bureau of Mines First Aid Training, but it is the idea to expand those clubs and teach the miner the advantage of such-things as the closed safety lamp, and also the regulations that have been made for his safety. In Illinois we can't operate with the closed lamp, because the miners in that section of the country are not educated to the advantages of the safety lamp. Another form of education has been taken up by the National Safety Council, consisting of voluntary organizations similar to the Institute, to which all mining men are invited to attend. Such conferences nave been held in the Lake Superior district, in Butte, and in Globe, Arizona, this year. These are to be extended throughout the coal mining regions. CHAIRMAN PRYDE: The Union Pacific Coal Company has also built two tank cars of 600 gallons capacity each. The tanks are connected with hose, so that water can flow from one tank to the other. A centrifugal pump is mounted on a truck, and connected to the front tank. This pump takes its power from the trolley wire. The discharge from the pump is perforated, so that it sprays the floor and sides of the entries. We expect to use this water train on main haulage ways where we have no sprinkling line.

Jan 1, 1923

PRESIDENT WHITESIDE: If the chair may be pardoned, he would like to say he knows something of the work of this committee, and I assure you that they have all worked faithfully and hard, holding meetings at least every other day, and sometimes oftener, hustling money and going through all the different work necessary to bring about and to make a successful occasion of this kind, and I-who really acted as an outsider and viewed their work-was certainly appreciative of their efforts, and I know you would have been had you been able to see how hard they all worked. One of the sad things in life always is when one becomes a "has-been." I have been more or less active in the work of the Institute ever since its in¬ception. Just why the high honor of President was conferred upon me I have never been able to fathom, but my time is about over and I am about to join the "has-beens," and while the position naturally has entailed a certain amount of work, it has been very pleasant work, and when one has the hearty co-operation of his fellow workers, such work is always a pleasure. It is, therefore, with a certain amount of regret that I lay down the gavel and take it up again to present to my successor; but in doing so, I wish to thank you, one and all, for your very hearty help and co-operation, and to wish my successor, Mr. George B. Pryde, all the possible success that can be his. Mr. Pryde. (Applause.) MR. PRYDE: I will make no extended speech at this time. I think possibly the next year I will have enough opportunity to do that; but I had a letter from my friend, Murphy, before this meeting, and he thought we were going to have a very good meeting; but I don't know the motive behind his letter. (Laughter.) I remember the story about the Scotchman who went to see the doctor, and the doctor said: "Sandy, you drink any?" "Oh, yes." "Well," he says, "you have got to cut that out. Do you smoke?" "Oh, yes; I smoke a great deal." "Well, you will have to cut that out also." And Sandy picked up his hat and started for the door. "Wait a minute, Sandy; you haven't paid me for my advice." "Yes, but I am not going to take your advice." (Laughter.) But I am deeply appreciative of the honor you have conferred upon me, electing me to be head of this Institute for the next year. I have belonged to this Institute, I should say, ever since it has been organized. This present session especially has been a very good session. As I look back over the different meetings, I think this one stands out among all the others in the papers presented and the spirit of co-operation that prevailed among the members here, and I am not going to ask your co-operation during the year; I am sure I will get it from all of you. I want to thank you for the honor conferred upon me. (Applause.) MR. WHITESIDE: The retiring President did not quite follow the reading of the by-laws, I think, in which it says that immediately after the election of a new President, the new President shall assume office, and I got so busy I forgot all about that. The committee which the chair decided to appoint is as follows. This is to formulate safety rules: For Utah, John Crawford, William Littlejohn; for Wyoming, Peter Patterson, Glen Knox; for New Mexico, William Risdon, Allan French; for Colorado, James Dalrymple, J. C. Roberts; and last and surely not least, as chairman of the committee, Mr. George B. Pryde. (Mr. Pryde later appointed D. Harrington as a member-at-large.) C. M. GODDARD: Mr. Chairman, we all realize that in a gaseous mine the application of, safety measures transcends everything else. Machinery is installed 100 per cent safe, as they might say, to take care of any condition

Jan 1, 1923

By G. A. Murphy

This tipple differs from the ordinary tipple only in that it embodies numerous refinements for grading and otherwise preparing the coal. Coal from the mines is delivered to the tipple over a surface tram. There are two tracks for loads, which will hold about forty cars, and one track for empties which will hold about the same number. The loads are fed to the dump by gravity from both tracks and are controlled by two squeeze blocks. These blocks are of the type originally designed by Mr. W. J. Elwood, but unlike the original blocks which were of wood and operated by hand levers, are built of steel and operated by com¬pressed air at 100 pounds pressure. They are capable of holding securely twenty-four three-ton cars on a grade of 2.5%. The dump is of the complete revolving type and has a capacity of five cars per minute. After being dumped the empty cars go to the usual kick-back and onto the empty track by gravity. The hopper under the dump has a capacity of approximately fifteen tons, and the coal from this hopper is fed to the shakers by a reciprocating feeder. The screens are of the usual shaker type. They are eight feet wide, seventy-two feet long in two sections, balanced, pitch 12° 30", travel six inches and the eccentric shaft makes 100 revolutions per minute. The upper section of the screen is shorter but heavier than the lower section, and contains the slack and nut screens, consisting of plates with 1 5/8" and 3" round perforations respectively. The lower section contains plates with 4 ½ ", 6" and 8" round perforations respectively, from top to bottom in the order named. The shaker is so arranged that nearly all changes for making the different sizes of coal are made by merely shifting levers. The most complicated change has been made in two and a half minutes; most of the other changes can be made in less than one minute and some of then without stopping the shaker. One of the refinements is what we call the degradation screens. Just before the coal leaves the shaker it goes over a screen with 1 3/8" round perforations, which takes out the fine coal made while the coal is going over the other perforations. This fine coal goes into hoppers and onto the degradation conveyor and to the slack chute. The different sizes of coal, excepting the slack, are delivered by the shaker onto three picking tables. These tables are horizontal for twenty-four feet and then hinged to form the loading booms, so that each picking table forms a unit of continuous conveyor. Centrally located under the picking tables and under the floor, is the refuse conveyor which runs at right angles to the tables. The impurities picked from the coal are dropped into openings in the floor and onto this conveyor, from which they are discharged into a bin of 100 tons capacity. From this bin the refuse is loaded into railroad cars through a gate. The slack may be loaded directly into railroad cars through a chute from the hopper under the shaker, or it may be conveyed to the rescreener. Gates are provided by which all or any part of the slack may be loaded either directly into railroad cars or conveyed to the rescreener. The rescreener is a shaker four feet wide with sixteen feet of plate perforated with 3/4" round holes. The framework is wood, the pitch is 5° and it is driven by eccentrics having a 5 3/4" throw running 143 R.P.M. It is hung on 1"x10" ash boards, rigidly fixed at the support and on the shaker, so that the spring of the boards allows for its movement. The eccentric rods are also of ash, rigidly fixed and spring to allow the movement of the eccentrics. The dust going through this shaker drops into a bin of 80 tons capacity and is loaded into railroad cars

Jan 1, 1925

Jan 1, 1969

PRESIDENT MOSES: Mr. Hall, can you tell us something that will help our cause? R. DAWSON HALL: I did not want to tell anything; I wanted rather to say something, if. I said anything at all, about my impressions regarding the safety of the mines in the West. We heard yesterday how terribly dangerous they were, and I think that is due to the natural conditions. It is interesting to note that many of the developments of safety, which you will find all through the country, had their origin here in the Rocky Mountain States. It has not been because the Rocky Mountain States have been negligent - though, of course, they could have been more active - but it is becaues the conditions have been such as to make accidents more numerous. Rock dusting by mechanical means was used here before any other country adopted it, let alone the United States. It is true that rock dusting was started in England; but it was by hand, as it remained with the Victor -American Fuel Company to be the first to distribute rock dust by machines, and that is to the credit of Mr. Murray, who was the man that did the original dusting in those mines. It was at Delagua, they put up shelving and put dust on it; they used the adobe, and Mr. Pryde, at Reliance, very early in the game, put dust in the Reliance Mines, and some of the dust, I believe, is there yet but they can hardly find it for the new dust. That is not all. I believe it was first in the Utah Fuel Company's mine that incombustible clay was used for stemming, and in the East, where we were in the habit of using slack entirely, that was a big advantage. Another thing that the West has originated has been the wetting of the chain in cutting. The people in Alabama took a great deal of credit for having used that very early, but not as early as Mr. Brennan did at the Hanna Mine, he having used water on the cutter bits in 1913. Another development was that the Phelps Dodge Corporation were the first people to use, I believe in the United States, storage battery locomotives for main haulage, and while they didn't go ahead with that, so far as putting in power trucks and mining machines, until just recently-I think the Consolidation Coal Company in the East managed to get ahead of them in that development,-notwith-standing, they were the earliest to use it for main haulage. When I came through this section of the country, in 1912, I think it was, I went through the mines of the Union Pacific Coal Company. I was surprised to see the extent to which fire-proofing had been carried out in that mine, with regard to non-combustible brattices and overcasts, which were of concrete; even the boxes were covered with sheet metal. They were very far ahad of us in that respect; far, far ahead of us in the East, because the East has its favorable conditions in the fact that most of the lump in the mines is more or less wet all the time. Another safety provision which has been taken by the Utah Fuel Company, was shooting from the surface. That has not spread very much in the, East, but it has been used in Oklahoma and the middle West. I think there is plenty of evidence that the Western people have been thinking for themselves, in going ahead and' establishing new standards in Safety. One of the most unusual things is this Safety Committee, permanent Safety Committee of the Rocky Mountain Coal Mining Institute, which has been endeavoring here to find out the conditions under which safety cant best be practiced. I think it is those who venture to. criticize the West that) have to show that in the East there is not the spirit which has led the Rocky Mountain region to endeavor to reduce its very terrible death rate that really exists. It has to be faced and it furnishes a cause, an incentive; for further work toward safety; but none can deny that the desire of the western mining man has been to find

Jan 1, 1926

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Jan 1, 2007

By Fredrick D. Palmer

U.S. ENERGY: PUTTING PEOPLE FIRST Assessing Goals, Needs and Resources ?Decision-makers must balance the needs of average Americans with the need for: ?A strong economy ?A clean environment ?A secure nation ?Events of recent years ?terrorist acts, multiple energy crises and a global focus on sustainable development ?magnify the need to balance these principles ?Coal ?domestic, abundant, affordable and increasingly clean ?meets these needs like no other energy source

Jan 1, 2003

The Morning Session of the Forty-Eighth Meeting of the Rocky Mountain Coal Mining Institute convened in the Little Theater of the Broadmoor Hotel, Colorado Springs, Colorado, at 9:30 a.m., June 4, 1952, Albert M. Keenan, Chairman, presiding. CHAIRMAN KEENAN: Ladies and Gentlemen, here we have our third and final clay of our program, and I wish to take this opportunity to thank all of you for your attendance, both in the past meetings and this one this morning... I am particularly delighted to see that we are all here this morning after the very enjoyable banquet last night. It is a little difficult to get people gathered up after such an occasion.

Jan 1, 1952

PRESIDENT PRYDE: Any discussion on Mr. Poster's paper? MR. J. BEVAN: I would like to ask the gentleman how fine the dust has to be to cause an explosion? MR. T. FOSTER: According to the Bureau of Mines, it is claimed coal passing through a 100 mesh screen would be considered fine enough. That is all I can learn from the different bulletins. MR. BEVAN: Will the coal dust be that fine; going back in the empty cars on the tipple in the mine? MR. FOSTER: Possibly a great deal of it would be. MR. BEVAN: Will the coal dust be that fine, going back, in the empty the coal dust going back in the cars on the tipple, and into the mine? MR. FOSTER: In some places, they are wetting the cars at the tipple, -in the Rock Springs District, we have as the trip goes out, they have a big pipe, and they souse the car, and wet the load, and in some places, near the timbers; that helps to a certain extent. That does not absolutely eliminate it all, but it helps considerable. MR. WM. LITTLEJOHN (Utah Fuel Company) : I think we have all listened very attentively to the paper that Mr. Foster has just read. He has brought up a subject rather close to my heart, for a long time. He mentions particularly, the Scofield disaster, which happened the first of May, 1900; two hundred men lost their lives in the explosion; and I think it is generally conceded that is about the first time it had ever been brought to the attention of coal miners or operators that such a thing was possible, namely, a purely coal dust explosion. The term "Scofield disaster" is rather a mistake, in a way; while the mine that exploded at the time is in the Scofield District all right, it is now known, and probably was known at that time, as the Winter Quarters Mine, one of the mines which belongs to the Utah Fuel Company at the present time, and did at that time. This mine

Jan 1, 1924

Jan 1, 1979