Both openings and passages leading thereto should be readily accessible at all times. Main-slope and drift openings should be separated by at least 50 feet of natural ground throughout their length. If one or both openings are shafts, the distance between the openings should be at least 200 feet to prevent possible distortion of both openings from ground movement. Shaft pillars and chain pillars between shafts ordinarily should not be removed in the final stage of mine operation. Each bed of coal and each level or entry in the mine should have at least two travelable openings connected directly or indirectly with both main outlets to the surface. It is not necessary that the two main outlets belong to the same mine if persons can travel safely to and out of either outlet from each mine. The important point is that both outlets should be readily accessible to all underground workmen; they should not be required to undergo undue physical discomfort in order to reach either of the outlets. All surface openings to underground workings that are not necessary for the operation of a mine should be kept securely closed to prevent unauthorized persons from entering, but they should not be closed in such a manner as to prevent the escape of employees in an emergency. All openings that are necessary for the operation of a mine or for escape should be guarded to prevent the entrance of unauthorized persons but should not prevent the escape of employees in an emergency. An outlet from a fan shaft is such an opening; a door could be installed at the surface with a lock that can be opened from the inside without the use of a key. Not more than 10 persons should be allowed at one time in a mine until connection has been made between two outlets to the surface. When only one outlet to the surface is available, owing to final mining of pillars or for other reasons, not more than 10 persons should be allowed in the mine at one time. The limit as to the number of men permitted to work in a mine under the conditions mentioned is set to keep the number of men working to a stated maximum. Obviously, the development of a new mine or the final work in an old mine requires workmen to accomplish the job. Many miners have had narrow escapes from inundations in various coal fields where flooded streams rose suddenly and the mine openings were below flood level. Such accidents can be prevented by making all drift, shaft, or slope openings penetrate the surface at least 20 feet vertically above the highest known flood level. In opening a mine in valleys or at low elevations of a watershed, the United States Weather Bureau records and other dependable sources of information, possibly including the older inhabitants of the region, should be consulted to obtain information about the highest known water level in the locality. ABANDONED MINE OPENINGS Many lives have been lost and millions of dollars in property damage have resulted from abandoned coal-mine openings being left unsealed. The problem of abandoned mines is primarily a local one involving the public interest, both mining and nonmining; in connection with stream pollution it becomes a matter of interstate concern. Most of the lives lost in abandoned mine openings are attributed to vitiated mine atmospheres. Even where gas is not present, there are instances where children especially, following their natural desire for exploration, have become lost in abandoned workings and were injured by falls of roof or collapse of old timbering. Numerous cases are on record where lives have been lost near the surface in abandoned mines. Some years ago three children entered an abandoned air shaft at a coal mine in Arkansas; they were overcome, and two men lost their lives in attempting to rescue the children. In another instance two small boys were overcome and died when they entered a drift in Kentucky to pick up coal. Five boys likewise were killed in an abandoned mine in Pennsylvania when they entered the drift to pick up coal. Abandoned mines are not only a hazard to the inexperienced person, but also to the experienced; several miners have met death while exploring such workings. Moreover, numerous fires are reported to have been started by illegal "stills" or other illegal business being operated in abandoned mines. Some of these fires have burned for years and have cost many thousands of dollars in damage to property and loss of life; they also have endangered homes and even cities or towns. Some State mining laws require the mine owner to fence or otherwise safeguard abandoned mine openings. Most of these laws appear to be inadequate as they do not specify how securely such openings shall be protected. Possibly some abandoned openings that are now unguarded were guarded in accordance with the law in effect at the time they were abandoned, but the method of guarding was not permanently effective. Some of the larger operating companies fence or fill abandoned openings, but many small companies operating shallow openings or along outcrops have failed to provide protection when they abandoned the openings. While some State laws require that openings and subsidence holes be guarded, legal enforcement in the case of a small operator whose operation is not large enough to come under the jurisdiction of the State mining department is difficult and often impossible. Mine operators should feel that they are morally obligated to guard effectively all abandoned surface openings and subsidence holes with adequate fences on which "danger" signs are posted conspicuously. ESCAPEWAYS Designated escapeways should be readily accessible from every section of a mine and should be kept in a safe condition, reasonably free from steam, dangerous gases, standing water, ice, and other obstructions. If practicable, they should be in intake air; if not in intake air, fire doors should be provided so they can be closed tightly in the event of an emergency to prevent smoke from entering the escapeway. The escapeway should be wide and high enough to permit men to travel safely and without undue physical discomfort. Direction signs should be posted conspicuously throughout a mine to indicate manways and designated escapeways and should be maintained in legible condition. Barrier gates that close automatically or overpasses or underpasses should be provided at places where manways cross haulageways. If only one of the escapeways has incombustible walls or lining, it should be the normal intake airway and should be the one regularly used by persons entering or leaving the mine. When the designated escapeways are shafts the following recommendations should be observed: 1. They should be equipped with a hoist and cage or with a travelable stairway if more than 30 feet in depth. 2. If equipped with a stairway, it should be of substantial construction, set at an angle not greater than 45° with the horizontal, and equipped on at least one side with suitable handrail; landing platforms should be at least 2 feet wide and 4 feet long, at easy and convenient distances, and should be railed effectively. 3. If the shafts are not more than 30 feet deep, a ladder may be used instead of a stairway. Such ladders should be well-fastened. The rungs should be attached securely, spaced equally, and not more than 15 inches apart. 4. Ladders or stairways should be kept in good repair, with landings free of debris. These four recommendations are made to assure unobstructed, safe, and readily available exit from a mine in the event of an emergency. If a designated escapeway inclines more than 30°, it should be equipped with a stairway or ladder and have landings at intervals not exceeding 50 feet apart. The landings provide resting places necessitated by fatigue from climbing and afford some protection for a falling person. If a designated escapeway is a drift or slope that inclines less than 45° with the horizontal, incombustible walls (or lining) should extend at least 200 feet from the entrance. If designated escapeways do not meet these requirements, adequate fire protection (water sprays, water lines, and hose or a heavy coating of rock dust) should be provided. OIL AND GAS WELLS Oil and gas wells that penetrate coal measures near mine workings introduce hazards in coal mining; these hazards have been recognized in those fields where oil, gas, and coal resources have been exploited simultaneously or separately. The history of these fields is replete with stories of serious mine fires, explosions, and miraculous escapes from both fires and explosions originating from either oil or gas finding its way into the mine workings through the strata or by mining into an unknown or uncharted and abandoned oil or gas well that had not been properly plugged. Some States that have resources of oil and natural gas in addition to coal have enacted laws requiring oil and gas producers to furnish coal-mine operators with complete information regarding the location of all active and abandoned oil or gas wells. Oil and gas producers usually comply willingly with such laws, so that the locations of the wells may be plotted accurately on the mine maps; this requirement is necessary to assure protection to all parties concerned. West Virginia has enacted a comprehensive law containing regulations that are the result of a careful study of oil and gas wells in the coal fields of the State as well as those of other States. In some districts oil and gas wells had been abandoned before coal mining was begun or before the enactment of State laws governing oil and gas wells. Many instances are known of coal-mine workings cutting into abandoned oil or gas wells inadvertently; the mine owners and officials were unaware of the existence of the wells. Abandoned oil and gas wells usually contain some explosive gas, which if allowed 8 West Virginia Department of Mines, Mining Laws: Charleston, art. 4, 1943, pp. 53–71. to enter a coal mine might create an extremely dangerous condition. Drill holes in advance of excavations, as in tapping abandoned mine workings suspected of containing gas or water, do not offer adequate protection against tapping abandoned oil or gas wells. Advance drill holes may pass an abandoned well by only a few inches, but excavation may penetrate the well. Under the circumstances about the only protection mine officials can provide is to have materials immediately available to seal the penetrated well promptly. The emission of gas from uncharted abandoned wells into mine workings has been the cause of some serious mine fires and explosions. Obviously, past experiences of the mine officials or those in neighboring mines will determine whether such well-sealing materials are made available throughout the mine workings. LOCATION OF WELLS Coal-mining companies that control all mineral rights, including oil and gas, by purchase or lease can require proper protection by those drilling the wells. However, many of the original owners of the lands disposed of the coal and oil and gas rights separately. Wells were drilled and later abandoned without being plugged, and records of their location were not made before the coal rights were sold or at least before the hazards of uncharted or unprotected wells were encountered by coal-mining companies. The exact location of all oil and gas wells penetrating workable coal beds is very important; a survey should be made to determine the exact position of the wells with respect to boundaries of the tract of land or Government survey monuments. A map showing the well locations and the courses and distances of the wells from the reference points should be prepared. It should also show the names of the adjoining property owners. A copy of the map should be filed at the county recorder's office and with the State department of mines. When the coal rights and oil and gas rights are owned or leased separately a copy of the map should be given to the coal-mine operator, who should locate the wells accurately on both his property and mine maps. If at all practicable, oil or gas wells should be located to conform as nearly as possible to a definite projected plan for development of the coal beds; the wells should be drilled through permanent pillars or located where protective pillars may be left around them, causing as little interference with the operation of the mine as possible. In drilling oil and gas wells they may deviate materially from the vertical; hence, it must not be assumed that the intersection of a well with the coal bed will be vertically beneath the top of the hole. The provision of a pillar of coal to protect a well from distortion by movement of the overlying strata after coal has been extracted and to protect the mine against leaking gas or oil must allow for a variation of several feet (5 to 25 feet or more) in the estimated point of intersection of the well with the coal bed. Wells drilled with churn drills are likely to be more nearly vertical than rotary-drilled wells, especially if the cover above the coal bed is shallow. In deeper wells a deviation of 1° from the vertical will cause a deviation of 171⁄2 feet horizontally at a depth of 1,000 feet. Many mining companies have found it necessary to make vertical surveys of drill holes to determine the exact position of the bottom of the holes. Where coal beds have thick cover (more than 1,000 feet) surveying of drill holes to determine possible departure from the vertical should be considered necessary in connection with any proposed plan to protect mine workings. PROTECTION FOR WELLS Oil and gas wells penetrating strata below beds of coal should be protected by a pillar of coal extending at least 50 feet from the well in every direction. All oil and gas wells penetrating a coal bed being mined should be indicated accurately on the mine map and the protective pillars delineated on it. The mine foreman and each section foreman should know the location of all oil and gas wells within their respective jurisdictions so that proper precautions can be taken to prevent encroachment on the protective pillars. If oil or gas wells penetrate open workings, the following precautions should be taken: 1. A surrounding wall or pier of cement, masonry, or concrete should be constructed, the diameter of which exceeds the height of excavation, or at least 48 inches. 2. The casing should be surrounded by an outer steel casing extending 20 to 30 feet below the coal bed and open to the outside atmosphere for relief of any gas liberated. The purpose of the first recommendation is to protect the well from damage by possible movement of the strata resulting from extraction of the coal and to protect the mine workings, particularly when pillars are not recovered. Before the workings are abandoned rock-filled cribs or rock columns should be erected around the wells, and after abandonment the workings should be sealed from the remainder of the mine with substantial, incombustible seals. A means of bleeding off any gas leakage from such a well is advisable; one means of venting is to drill a borehole from the surface into the abandoned area near the well. The purpose of the second recommendation is to seal the inner-well casing above and below a penetrated coal bed and to provide a means of venting any gas leakage. PLUGGING ABANDONED WELLS Every oil or gas well penetrating a workable coal bed should be plugged properly from the bottom of the well to the surface when abandoned and a record made of such plugging. If necessary, a 2-inch vent pipe should extend from at least 30 feet below the lowest coal bed to not less than 10 feet above the surface. A good method is to plug the abandoned well with a cement-sand-water mixture to a point at least 20 feet above any oil-, gas-, or water-bearing stratum. After the cement has set the remainder of the well may be plugged with mud, clay, or other nonporous material. COAL-MINE OPERATION IN OIL OR GAS FIELDS A coal mine in a field producing oil or gas should be operated as a gassy mine, regardless of whether explosive gas is liberated from the coal bed being mined. Such a mine should be operated with permis |