As part of the investigation, the Ground Support Division of MSHA’s Denver Safety and Health Technology Center conducted an evaluation of the ground control aspects of the Petitioner’s Willow Creek Mine, and submitted a report of its findings. The report substantiated that this operation will be mining multiple, gassy, dipping coal seams under deep cover and rugged topography. In fact, beginning with projected Panel D-1, the Willow Creek Mine will be mining under more than 2,000 feet of cover. The report stressed that neighboring coal mines, operating under such cover and having the same type of conditions, have had problems with coal bursts, including a recent fatality. Due to the coal seam characteristics, depth of cover and topography of the overburden of the Willow Creek Mine, two-entry gate roads shall be developed and used for all future longwall mining in those coal seams.
Due to the documented hazards associated with mining in this coal seam(s), application of 30 CFR 75.350 to the subject mine will result in a diminution of safety to the miners and the special terms and conditions set out below will at all times provide a safe work environment to the miners.
On the basis of the petition and the findings of MSHA's investigation, Cyprus Plateau Mining Corporation, is granted a modification of the application of 30 CFR 75.350 to its Willow Creek Mine.
Wherefore, pursuant to the authority delegated by the Secretary of Labor to the Administrator for Coal Mine Safety and Health, and pursuant to Section 101(c) of the Federal Mine Safety and Health Act of 1977, 30 U.S.C., sec. 811(c), it is ordered that
Cyprus Plateau Mining Corporation's Petition for Modification of the application of 30 CFR 75.350 in the
Willow Creek Mine is hereby:
GRANTED, for use of belt air in two-entry mining systems, conditioned upon compliance with the following terms and conditions:
1. An early warning fire detection system (Carbon monoxide monitoring system) shall be installed as follows:
a. The carbon monoxide monitoring system shall be installed in the belt entry and primary escapeway of all two-entry development, longwall set-up and recovery, and retreat mining systems.
b. Sensors located in the belt entry and primary escapeway shall be installed:
(1) Near the center and in the upper third of the entry in a location that would not expose personnel working on the system to unsafe situations.
(2) At a location to prevent damage from mobile equipment.
(3) At intervals not to exceed 1,000 feet along the entry.
c. Sensors shall be installed between 50 and 100 feet downwind of each belt drive, drive/belt take-up combination, and each tailpiece. However, the sensor at the belt tailpiece on a longwall retreat mining system may be installed between 25 and 100 feet downwind.
d. Sensors required to be installed in the primary escapeway of two-entry systems shall be located at the mouth of the section and at the beginning of the working section.
e. During initial two-entry development mining, sensors shall be installed for a distance of 4,000 feet outby the section loading point in the intake air course which provides the intake air split to the two-entry development. As the two-entry system advances, these sensors may be moved into the two-entry section. Once the two-entry section has advanced a total of 4,000 or more feet, sensors are not required to be installed in the intake entry outby the mouth of the two-entry section.
f. Where the return air is directed out of the belt conveyor entry during development, a sensor shall be installed in the belt entry 25 feet inby that location and a sensor shall be installed between where the return air is directed out of the belt conveyor entry and the ventilation box check device.
g. A sensor shall be installed in the mainline conveyor belt entry between 50 and 100 feet downwind of the location where the two-entry conveyor belt discharges on to the main line conveyor belt.
h. Sensors shall not be located in intersections, abnormally high areas or in other areas where airflow patterns do not permit products of combustion to be carried to the sensors.
i. During retreat mining, sensors shall be installed at a location not more than 150 feet inby and outby the point-feed in the belt entry.
2. The early warning fire detection system shall be designed and maintained as follows:
a. The carbon monoxide monitoring system shall be capable of providing both visual and audible signals. A signal device shall be located on the surface of the mine where it can be seen or heard by a responsible person, designated by the operator and trained in the operation of the carbon monoxide detection system and the fire fighting and evacuation plan. The responsible person shall be on duty at all times when miners are underground in a two-entry system or when the conveyor belt is operating in a two-entry section. A visual or audible alert signal shall be activated when the carbon monoxide level at any sensor reaches the level determined in paragraph 4. An audible and visual alarm signal distinguishable from the alert signal shall be activated when the carbon monoxide level at any sensor reaches the alarm level determined in paragraph 4.
b. A signal device(s) shall be located on the section so that it can be seen or heard by at least one person at all times when miners are underground in a two-entry system. Audible and visual alarm devices used on sections shall be of the permissible type or enclosed in MSHA-certified (approved) explosion-proof enclosures if installed in areas where permissible equipment is required. The District Manager may approve an alternate alarm signal device(s) that will afford equal or better protection. To assist the District Manager in making a determination, the alternate alarm signal device(s) submitted by the operator may be evaluated by MSHA's technical support staff as deemed appropriate by the District Manager
c. Audible and visual alarm devices located on the section(s) shall be activated by all sensors:
(1) Required during initial two-entry development mining, stipulated in paragraph 2(e), if carbon monoxide reaches the established alarm levels as determined in paragraph 4.
(2) From the mouth of the panel to the section loading point if carbon monoxide reaches the established alarm levels determined in paragraph 4.
d. The carbon monoxide monitoring system shall be capable of monitoring electrical continuity and detecting electrical malfunctions such as open-circuits, short-circuits, ground-faults and, where appropriate, pneumatic malfunctions in the system.
e. The carbon monoxide monitoring system shall be capable of identifying any activated sensor(s).
f. The carbon monoxide monitoring system shall be capable of giving warning of a fire for a minimum of 4 hours after the source of power to the belt is removed as required by 30 CFR 75.1103-4(e).
g. The carbon monoxide monitoring system shall limit time delay periods for alert and alarm signals to not more than a total of 180 seconds. If used, time delays shall be specified in the mine ventilation plan. Time delays shall only be used if the mine uses diesel equipment.
3. Air velocity requirements in the two-entry system.
a. The air in the carbon monoxide monitored entry(s) shall have a velocity of at least 50 feet a minute and have a definite and distinct movement in the designated direction.
b. Velocity measurements shall be determined at locations in the entry which are representative of the cross
-sectional areas found throughout the entry and not at locations where the entry is abnormally high (e.g. belt drives) or low (e.g. under overcasts).
4. Determination of the carbon monoxide ambient, alert, and alarm levels shall be as follows:
a. Upon implementation of this Proposed Decision and Order, the interim ambient level shall be 5 ppm. Ambient shall be determined upon completion of the first longwall panel; (i.e., two-entry development, longwall set-up and recovery and longwall retreat), or if a test conducted under paragraph 4(d)(1) is started before the first panel is completed, then ambient shall be determined by the end of this test. The ambient level shall be determined under normal mining conditions as follows:
(1) Properly calibrated carbon monoxide sensors shall be used for an ambient determination where this Proposed Decision and Order requires carbon monoxide monitoring to be conducted. An ambient determination shall be made by either of the following methods:
(i) Measurements from all two-entry sensors for each separate air split shall be used. Continuous readings shall be taken and recorded for a total of five (5) consecutive shifts to establish a history of carbon monoxide levels. The average of the data collected for each air split will determine its ambient level; or
(ii) An equally effective method approved as part of the Ventilation Plan.
(2) MSHA shall be notified when ambient levels will be determined and provided the opportunity to assist in the ambient level determination.
(3) Ambient levels shall be representative of normal operating conditions. Diesel equipment shall not be idled unnecessarily in the air split where the ambient level is being determined. MSHA may request that the number and type of diesels entering and leaving the two-entry system be documented during ambient determination.
(4) Ambient levels can be different for the two air courses in the two-entry system. Ambient levels can also be different for development, retreat, longwall set-up and longwall recovery. If different ambient levels are determined, either the lowest ambient level can be utilized throughout the two-entry system or the carbon monoxide monitoring system can be divided with the appropriate pre-determined ambient level used.
b. The interim alert and alarm levels during longwall set-up and recovery shall be 10 ppm and 15 ppm, respectively above the appropriate ambient level. These alert and alarm levels shall be appropriately reduced by the operator based on the results of testing described in paragraph 4(d)(1)(i) and (ii) below and approved by the District Manager in the Ventilation Plan.
c. The interim alert and alarm levels for the primary escapeway entry (intake entry) shall be 10 ppm and 15 ppm, respectively above the appropriate ambient level. These alert and alarm levels shall be appropriately reduced by the operator based on the results of testing described in paragraph 4(d)(1)(i) and (ii) below and approved by the District Manager in the Ventilation Plan.
d. The interim alert and alarm levels for the belt entry shall be 10 ppm and 15 ppm, respectively above the appropriate ambient level. Carbon monoxide data from the early warning fire detection system shall be submitted monthly to the District Manager. The data shall be evaluated monthly to determine if the alert and alarm levels can be reduced, taking into account problems associated with nuisance alarms. The monthly evaluation shall continue until the first panel (development and retreat) is completed. The alert and alarm levels established at the completion of the development for the first panel shall be established as the interim alert and alarm levels for retreat mining of that panel. If practical, the alert and alarm levels shall be reduced until they correspond to the levels which would be established from Tables 1 - 6 which are attached and incorporated into this Proposed Decision and Order. The alert and alarm levels established during the mining of the first panel shall establish the alert and alarm levels for subsequent panels unless a condition would change resulting in an alert and alarm reevaluation as described in paragraph 5.
(1) If alert and alarm levels used are higher than the levels in the tables, the operator shall:
(i) Conduct a test utilizing other devices as set out in paragraph 10, other than a conventional carbon monoxide system, which will provide an early warning fire detection system that might prove more effective in an environment containing diesel engine exhaust;
(ii) Diligently investigate technological innovations to reduce diesel engine carbon monoxide emissions in an effort to reduce alert and alarm levels back to the appropriate table levels. If available technological innovations appear to be reasonable and practical and could be expected to have a positive effect on lowering carbon monoxide emissions, the operator shall test the device for potential use in the two-entry system; and
(iii) Identify any individual diesel equipment that is contributing to higher carbon monoxide levels in the two-entry system and causing an excessive number of nuisance alert and alarm signals. The operator shall then prohibit entry of the identified diesel equipment in the two-entry system until the equipment is serviced to reduce its carbon monoxide levels.
(2) The carbon monoxide alert and alarm levels established from the tables can be different for the two air courses in the two-entry system. Alert and alarm levels can also be different for development, retreat, longwall set-up and longwall recovery. The number of carbon monoxide alert and alarm settings used shall be minimized and may be limited by the District Manager to maintain system effectiveness.
(3) The cross-sectional areas used for alert and alarm level determination from the tables shall be measured at locations in the entry representative of the cross-sectional areas found throughout the belt entry and not at locations where the entry is abnormally high (i.e. belt drives) or low (i.e. under overcasts).
5. The carbon monoxide alert and alarm levels and the ambient level(s) determined in paragraph 4 shall be submitted to the District Manager for verification and shall be included in the mine ventilation plan. The District Manager is authorized to require reevaluation of alert, alarm, and ambient levels if any condition changes. Such changes can include air quantity, if it affects the alert and alarm levels selected from the Tables, or significant increases in carbon monoxide in the mine ambient atmosphere which are sufficient to affect the alert, alarm or ambient level. The mine ventilation plan shall be revised to reflect such changes.
6. When the carbon monoxide monitoring system gives a visual or audible alert signal, miners in the working section(s) on the same split of air shall be notified immediately by the responsible person designated by the operator at the surface location described in paragraph 2(a) and an investigation shall be conducted to determine the cause of the actuation. When the carbon monoxide system gives an audible and visual alarm signal, all miners, except those involved in investigating the alarm and/or fighting the fire, in the affected split(s) of air shall be withdrawn immediately to a safe location at least one sensor outby the sensor(s) activating the alarm, unless the cause is known not to be a hazard to the miners. However, if the alarm is activated in the belt entry during development of a two-entry panels, all miners in the two-entry system shall withdraw immediately to the mouth of the panel, unless the cause is known not to be a hazard to the miners. When the carbon monoxide warning system gives an audible and visual alarm signal at shift change, no one shall be permitted to enter the mine except qualified persons designated to investigate the source of the alarm. If miners are enroute underground, they shall be held at, or be withdrawn to, a safe location that is at least one sensor outby the sensor(s) activating the alarm. When a determination is made as to the source of the alarm, and that the mine is safe to enter, the miners shall be permitted underground. The mine evacuation plan required by 30 CFR 75.110123(a) shall be revised to specify the actions to be taken when alert and alarm signals occur. Such revisions shall be approved by the District Manager. A record of each alert and alarm signal given, and the action taken for alarms shall be maintained at the mine for a period of 1 year.
7. The responsible person(s) designated by the operator stationed at the surface location described in paragraph 2(a) shall have two-way communications with all working sections. When the established alert and alarm levels are reached, such person(s) shall notify the affected working sections and other affected locations where personnel are normally assigned to work. The responsible person(s) shall also be trained in the operation of the carbon monoxide monitoring system and in the proper procedures to follow in the event of an emergency or malfunction and, in that event, shall take appropriate action immediately.
8. The carbon monoxide monitoring system shall be examined visually according to the manufacturer's recommendations at least once each shift
miners travel or work in the two-entry system. Also, at least once each shift
miners travel or work in the two-entry system each carbon monoxide sensor shall be visually examined. The system shall be inspected by a person qualified for such work at intervals not exceeding seven (7) days. A qualified person shall ensure that the system is operating properly, and that the required maintenance, as recommended by the manufacturer, is performed. The monitoring sensors shall be calibrated with known quantities of carbon monoxide-air mixtures at intervals not exceeding 31 calendar days. An inspection record shall be maintained on the surface and made available to
MSHA personnel, employees or the miners' representative. The inspection record shall show the date and time of each inspection, calibration, and all maintenance performed, whether at the time of the weekly inspection or otherwise.
9. If at any time the carbon monoxide monitoring system, methane monitoring system or any portion of the systems required by this Proposed Decision and Order has been de-energized for reasons such as routine maintenance or failure of a sensor unit, the belt conveyor may continue to operate provided the miners in the affected working section(s) are notified and the affected portion of the entry(s) is continuously patrolled and monitored for carbon monoxide and/or methane in the following manner until the affected monitoring system is returned to normal operation:
a. The patrolling and monitoring must be conducted by a person or persons trained in the mine evacuation plan, the operation of a handheld carbon monoxide and methane detection device(s), and the use of the two-way communication device provided. When patrolling and monitoring, the following conditions shall be met:
(1) The trained person(s) performing monitoring shall be provided with a two-way communication device enabling the person(s) to communicate with the surface. Mine phones located at a maximum distance of 1,000 feet may be used for the communication device. When used for this purpose, the mine phone location shall be conspicuously identified.
(2) Each of these trained persons shall be provided with a handheld carbon monoxide and methane detection device(s). A carbon monoxide and methane detection device(s) shall also be available for use on each two-entry working section in a two-entry system.
(3) The trained person(s) performing monitoring shall provide an alert or alarm warning to the responsible person at the surface location when the hand-held carbon monoxide instrument measures a concentration 10 ppm above the alert or alarm level for the appropriate inoperative sensor(s) location, described in paragraph 4 (b - d), since no time delay is incorporated in the measurement by the hand-held device.
(4) If one sensor becomes inoperative, the trained person shall monitor at that sensor location;
(5) If two or more adjacent sensors become inoperative, a trained person shall patrol and monitor the area affected at least once each hour; and
(6) If the complete system becomes inoperative, a sufficient number of trained person(s) shall patrol and monitor the affected entries of the mine so that the affected entries will be traveled once each hour in their entirety.
b. The procedure outlined above is applicable only for a period of time that is to be determined by the reasonable amount of time required to repair or replace the equipment causing the malfunction. The mine operator shall begin corrective action immediately and continue until the defective equipment causing the malfunction is replaced or repaired. The responsible person on the surface shall immediately establish two-way communication with the working section(s) and notify them of the particular malfunction(s) or problem.
10. Upon implementation of this Proposed Decision and Order, the operator shall conduct a study of devices, other than a conventional carbon monoxide system, such as the diesel discriminating sensors, smoke detectors, etc., which will provide an early warning fire detection system that may prove as effective in an environment containing diesel engine exhaust. The operator may test the feasibility of utilizing these devices to comply with the terms and conditions of this Proposed Decision and Order applying to early warning fire detection. The proposal for testing any such device shall be submitted to MSHA for approval by the District Manager as part of the Mine Ventilation Plan. During the testing period, all of the terms and conditions of this Proposed Decision and Order shall remain in effect except those terms and conditions applying to early warning fire detection and diesel operation modified by MSHA in the approved ventilation plan to enable the test to be conducted. When it has been demonstrated to MSHA that another device is practical and is as effective as a conventional carbon monoxide monitoring system, the details of such system shall be incorporated into the approved Ventilation Plan and shall be used to comply with terms and conditions of this Proposed Decision and Order.
11. The concentration of respirable dust in the intake air coursed through a belt conveyor haulageway shall not exceed 1.0 mg/m3. Compliance with this requirement will be determined by establishing a designated area (DA) sampling location within 15 feet outby the working section belt tailpiece and sampled in accordance with 30 CFR 70.208. The specific DA sampling location shall be identified in the mine ventilation plan with a four-digit number beginning with 8, followed by the middle two digits of the MMU number, and ending with 9 (i.e., 8119 for MMU 0110).
12. During development mining, a designated area (DA) sampling location shall be established on the roof bolting machine operator and sampled in accordance with 30 CFR 70.208. The specific DA sampling location shall be identified in the mine ventilation plan with a four-digit number beginning with 9, followed by the middle two digits of the MMU number, and ending with 9 (i.e., 9119 for MMU 0110).
13. A methane monitoring system utilizing methane sensors shall be installed to monitor the belt entry during development while the belt entry is utilized as a return aircourse as follows:
a. The methane sensors shall be located so that the belt air is monitored near the mouth of the development, near the tailpiece of the belt conveyor, and at or near any secondary belt drive unit(s) installed in the belt haulage entry.
b. Methane sensors shall be installed near the center and in the upper third of the belt entry, in a location that would not expose personnel working on the system to unsafe situations.
c. The methane monitoring system shall be capable of monitoring electrical continuity and detecting electrical malfunctions such as open-circuits, short-circuits, ground-faults and, where appropriate, pneumatic malfunctions in the system.
d. The methane monitoring system shall be capable of providing both audible and visual signals on both the working section and at a location on the surface of the mine where a responsible person designated by the operator will be on duty at all times when miners are underground in a two-entry section or when a conveyor belt is operating in a two-entry section. This trained person shall have twoway communication with all working sections. The methane monitoring system signals shall be distinguishable from the carbon monoxide system signals in order to differentiate between the two systems. The signal device shall be located on the section so that it can be seen or heard by at least one person at all times when miners are underground in the two-entry system. The system shall initiate alarm signals when the level is 1.0 volume per centum. The methane monitoring system shall be designed and installed to de-energize the belt conveyor drive units when the methane level reaches 1.0 volume per centum. Upon notification of the alarm, miners shall de-energize all other equipment located on the section.
e. The methane monitoring system shall be visually examined according to the manufacturer's recommendations at least once each shift miners travel or work in the two-entry system. Also, at least once each shift miners travel or work in the two-entry system each methane sensor shall be visually examined. The system shall be inspected by a person qualified for such work at intervals not exceeding seven (7) days. A qualified person shall ensure that the system is operating properly and that the required maintenance, as recommended by the manufacturer, is performed. The monitoring sensors shall be calibrated with known quantities of methane-air mixtures at intervals not exceeding 31 calendar days. An inspection record shall be maintained on the surface and made available to all interested persons. The inspection record shall show the date and time of each inspection, calibration, and all maintenance performed, whether at the time of the weekly inspection or otherwise.
14 A new conveyor-belt flammability test has been developed by MSHA. When compatible belting identified by MSHA as having passed the new flame-resistant test becomes commercially available, all subsequent belt purchases for the two-entry system shall be of this improved type belting.
15. Where the belt entry is used as an intake air course to ventilate the working section and the air in the belt entry is diverted from the primary escapeway at a point feed, the point feed shall be a constructed as a permanent ventilation control and provided with a means of closure. The design of the point feed shall be specified in the mine ventilation plan.
16. During the development of two-entry panels, longwall set-up and recovery and retreat operations:
a. Procedures shall be developed to establish administrative controls for planning and communication of activities which are known to result in elevated carbon monoxide levels which do not present a hazard to miners working inby. All persons working in the two-entry longwall panel shall be trained in these administrative control procedures. In the case of diesel equipment operators, the training shall include carbon monoxide sensor locations so as to minimize false alarms. Diesel equipment operators shall be instructed not to idle machines near carbon monoxide sensors. Administrative controls shall also be used to minimize the number and type of pieces of diesel equipment in the two-entry system, to notify a responsible person on the working section when any diesel equipment is operating in the two-entry system and when welding operations are performed in order to avoid nuisance alert and alarm signals. These administrative controls shall be incorporated into the mine ventilation plan.
b. Mining operations which utilize diesel-powered equipment underground on a two-entry system shall comply with the following provisions:
(1) Only diesel equipment approved under 30 CFR Part 36 (Part 36) and maintained to those requirements shall be permitted where permissible electric face equipment is required.
(2) The air quantity required when diesel equipment is in the two-entry system shall comply with the following:
(i) When Part 36 diesel equipment is operated in the two-entry system, the minimum quantity of air for a single unit shall be at least that specified on the approval plate for that equipment. When multiple Part 36 diesel units are operated in the two-entry system, the minimum quantity shall be the sum of 100 percent of the approval plate air quantity for each additional unit.
(ii) When diesel equipment not approved or maintained under Part 36 is operated in the two-entry system, the minimum quantity of air for a single unit shall be at least 150 cfm per rated horsepower, or that specified on a 30 CFR Part 7 (Part 7) Subpart E MSHA approval plate. The approval plate air quantity may be used provided the engine is maintained in approved condition. If the ventilating air quantity for non-approved diesel equipment is calculated using the rated horsepower, it shall be conspicuously marked on the machine by the mine operator. However, once 30 CFR 75.1909(a)(1) becomes effective, only Part 7 Subpart E approval plate air quantities shall be used for minimum air quantity determinations. When multiple diesel units which are not approved or maintained under Part 36 are operated in the two-entry system, the minimum air quantity shall be the sum of 100 percent of each additional unit.
(iii) An exception to the air quantity calculations described above will apply for ambulance equipment used for emergency purposes only.
(3) The air quantity required in paragraph 16 (b) (2)(i) and (ii) shall be determined from measurements made in the air split where diesel equipment is operated.
(4) All Part 36 dieselpowered equipment operated in any two-entry system shall be provided with a fire suppression system.
(5) All diesel-powered equipment which is not approved and maintained under Part 36 and operated on any two-entry system, except ambulance equipment used for emergency purposes only, shall be provided with and maintained with the following:
(i) An automatic and manual activated multipurpose dry chemical type (ABC) fire suppression system that is listed or approved for installation on diesel equipment by a nationally recognized independent testing laboratory. The manual fire suppression system shall be capable of being activated from inside and outside of the machine's cab. The manual activator located outside the cab shall be on the end of the machine opposite the engine.
(ii) An automatic engine shut down/fuel shut off system tied into the activation of the fire suppression system.
(iii) A means to maintain, below 302 degrees Fahrenheit, the surface temperature of the exhaust system of diesel equipment that cuts or moves rock or coal, equipment that performs drilling or bolting functions, equipment that moves longwall components, and lube units. Other diesel equipment which does not perform these functions shall include a means to prevent the spray from ruptured diesel fuel, hydraulic oil, and lubricating oil lines from being ignited by contact with engine exhaust system component surfaces such as shielding, conduit, or non-absorbent insulating materials.
(iv) An automatic closing, heat-activated shut off valve on diesel fuel lines either between the fuel injection pump and fuel tank if the fuel lines are constructed of steel or located as close as practical to the fuel tank.
(v) A sensor to monitor the temperature and provide visual warning of an overheated cylinder head on air cooled engines.
(6) Except ambulance equipment used for emergency purposes only, all diesel-powered equipment, operated on any two-entry system, having electrical circuits and components associated with or connected to electrical systems utilizing storage batteries and integral charging systems, shall be provided with and maintained with the following requirements:
(i) Overload and short circuit protection must be provided for electric circuits and components in accordance with 30 CFR 75.518 and 75.518-1;
(ii) Each electric conductor from the battery to the starting motor must be protected against short circuit by fuses or other circuit-interrupting devices placed as near as practicable to the battery terminals;
(iii) Each branch circuit conductor connected to the main circuit between the battery and charging generator must be protected against short circuit by fuses or other automatic circuit-interrupting devices;
(iv) The electrical system shall be equipped with a circuit-interrupting device by means of which all power conductors can be deenergized. The device must be located as close as practicable to the battery terminals and be designed to operate within its electrical rating without damage. The device shall not automatically reset after being actuated. All magnetic circuit-interrupting devices must be mounted in a manner to preclude their closing by force of gravity;
(v) Each motor and charging generator must be protected by an automatic overcurrent device. One protective device will be acceptable when two motors of the same rating operate simultaneously and perform virtually the same duty;
(vi) Each ungrounded conductor must have insulation compatible with the nominal system voltage. Insulation materials must be resistant to deterioration from engine heat and oil. Electric conductors must meet the applicable requirements of 30 CFR 75.513 and 75.513-1, except electric conductors for starting motors, which must only meet the requirements of 30 CFR 75.513;
(vii) All wiring must have adequate mechanical protection to prevent damage to the cable that might result in short circuits;
(viii) Sharp edges and corners must be removed at all points where there is a possibility of damaging wires, cables, or conduits by cutting or abrasion. The insulation of the cables within a battery box must be protected against abrasion;
(ix) When insulated wires other than cables pass through metal frames, the holes must be substantially bushed with insulated bushings or otherwise be protected from mechanical damage from sharp edges or corners. Cables must enter metal frames of motors, splice boxes, and electric components only through proper fittings. All electrical connections and splices must be mechanically and electrically efficient, and suitable connectors shall be used. All electrical connectors or splices in insulated wire must be reinsulated at least to the same degree of protection as the remainder of the wire; and
(x) The battery must be secured to prevent movement, and must be protected from external damage by position. Batteries that are not protected from external damage by position must be enclosed in a battery box. Flame-resistant insulation treated to resist chemical reaction to electrolyte must be provided on battery connections to prevent battery terminals from contacting conducting surfaces.
(xi) A battery box, including the cover, must be constructed of steel with a minimum thickness of 1/8 inch, or of a material other than steel that provides equivalent strength;
(xii) Battery-box covers must be lined with a flame-resistant insulating material permanently attached to the underside of the cover, unless equivalent protection is provided. Battery-box covers must be provided with a means for securing them in closed position. At least 1/2 inch of air space must be provided between the underside of the cover and the top of the battery, including terminals;
(xiii) Battery boxes must be provided with ventilation openings to prevent the accumulation of flammable or toxic gases or vapors within the battery box. The size and locations of openings for ventilation must prevent direct access to battery terminals;
(xiv) The battery must be insulated from the battery-box walls and supported on insulating material. Insulating materials that may be subject to chemical reaction with electrolyte must be treated to resist such action; and
(xv) Drainage holes must be provided in the bottom of each battery-box.
(7) Diesel fuel shall not be stored in the two-entry system. Diesel-powered equipment which is not approved and maintained under Part 36 shall not be refueled in the two-entry system.
(8) Diesel equipment shall not be idled unnecessarily in the two-entry system.
(9) Diesel equipment shall not be used for face haulage equipment on the working section, except that diesels may be used on the working section for cleanup, set-up, and recovery, or similar non-coal haulage purposes.
(10) A check of diesel-powered equipment which is not approved or maintained under Part 36 shall be performed before the equipment is permitted to operate on a two-entry system. The check shall consist of a visual exam of the hand-held fire extinguisher and automatic fire suppression system indicator panel, and for leaking diesel fuel, hydraulic oil and lubricating oil lines. The check shall be made at least once per shift if the equipment is to be used on the two-entry system. If this visual exam reveals a hazard such as a faulty fire extinguisher, a malfunction with the fire suppression system, or a leaking line, the diesel-powered equipment shall not be operated in the two-entry system until repaired. Any hazard that cannot be corrected at that time shall be reported to the responsible foreman and made part of and retained in the same manner as the on-shift examination hazardous condition record.
(11) All diesel-powered equipment must be continuously attended by a person designated by the operator who can see the equipment at all times during its operation. The designated person shall be capable of shutting off the equipment and activating the fire suppression system.
(12) If non-Part 36 diesel-powered equipment needs to be "jump" started due to a dead battery in any two-entry system, a methane check shall be made, by an MSHA approved detector, prior to attaching the "jumper" cables. The equipment shall not be "jump" started if air contains 1.0 volume per centum or more of methane.
(13) A diesel equipment maintenance program shall be adopted and complied with by the operator. The program shall include the examinations and tests specified in the manufacturers' maintenance recommendations as it pertains to diesel carbon monoxide emissions and items required by paragraph 16(b)(5). A record of these examinations and tests shall be maintained on the surface and be made available to all interested persons.
(14) Miners assigned to work in the two-entry system shall be trained on the various types of fire suppression systems used on diesel equipment operated in the two-entry mining systems. This training shall be conducted prior to the implementation of this Proposed Decision and Order and shall be included as part of annual training.
c. Mantrip cars or personnel carriers or other transportation equipment shall be maintained on or near the working section and be of sufficient capacity to transport all persons who may be in the area and shall be located within
500 feet of the section loading point.
d. Fire doors designed to quickly isolate the working section in emergency situations shall be located near the mouth, in the two-entry system. The fire doors shall be maintained operable until all mining in the two-entry system is completed. The fire fighting and evacuation plan should specify the designated person(s) responsible for the closing of the fire doors to prevent contaminants such as smoke and carbon monoxide from entering the two-entry system from a fire located outby. Notification of personnel and de-energization of electric power inby the fire doors are required any time they are to be closed.
e. When the hydraulic fluid pump station for the longwall support system is located in the two-entry system, it shall be installed and maintained as follows:
(1) The pumps shall be equipped with an automatic fire suppression system.
(2) Only Isosynth VX110 BF2 hydraulic fluid or other approved fluid of similar composition/properties may be used.
(3) The pump station shall be maintained to within 1,200 feet of the longwall face.
(4) In addition to the concentrate contained as part of the hydraulic pump station system, hydraulic concentrate stored on the two-entry system shall be limited to 500 gallons.
(5) A carbon monoxide sensor shall be installed between 50 and 100 feet downwind of the hydraulic pump station. The sensor shall be installed at a location to prevent damage from mobile equipment.
f. Two separate lines or systems for voice communication shall be maintained in the two-entry mining system. Phones shall be installed every 1,000 feet and within one crosscut of the location of the carbon monoxide sensor in the belt and intake entries. The two systems shall not be routed through the same entry. The method(s) of communications shall be approved by the District Manager as part of the Ventilation Plan.
g. At least one selfcontained selfrescuer shall be available for each person on the working section at all times and shall be carried into the section and carried on the section, or stored on the section, while advancing the twoentry development. During longwall set-up and recovery and retreat mining, at least two self-contained selfrescuers shall be available for each regularly assigned person on the working section. One shall be stored near the face in the headgate entries at a readily accessible location and one shall be stored near the tailgate entries. These locations shall be specified in the storage plan approved by the District Manager.
h. In addition to the requirements of 30 CFR Part 75.1100-2 (b), firehose outlets with valves every 300 feet shall be installed along the intake entry. At least 500 feet of firehose with fittings suitable for connection with the outlets shall be stored at each strategic location along the intake entry. The locations shall be specified in the firefighting and evacuation plan.
i. Compressor stations and unattended portable compressors shall not be located in the two-entry system.
j. During development of the twoentry system, a rock dusting unit shall be installed in the belt conveyor entry near the section loading point. Also, during longwall retreat mining in the two-entry system, a rock dusting unit shall discharge at or near the last tailgate shield. These rock dusting units shall be operated continuously when coal is being produced to render inert float coal dust in these entries, except when miners are performing maintenance, inspections/examinations, or other required work in these areas.
17. During retreat mining of the longwall panels:
a. Two separate intake aircourses within each long-wall panel shall be provided to each two-entry longwall. Both aircourses may be located on the same side of the panel in accordance with paragraph 15.
b. A safe travelway shall be maintained for each longwall panel through the tailgate side of the longwall in accordance with 30 CFR 75.215 and 75.222. MSHA shall be notified immediately if a roof fall occurs that impedes travel in a tailgate travelway, or if a travelway otherwise becomes unsafe for travel. A weekly examination of tailgate travelways shall be conducted by a qualified person and the results recorded.
c. If a two-entry wrap-around bleeder system is used, a travelway from the headgate to the inby bleeder entries shall be maintained in accordance with the approved roof control plan.
18. The details for the early warning fire detection system and methane monitoring system as described in this Proposed Decision and Order (including, but not necessarily limited to, type of monitor, specific sensor location on the mine map, and the alert and alarm levels) shall be included as a part of the mine ventilation plan required by 30 CFR 75.370. The District Manager may require additional carbon monoxide or methane sensors and or alarm devices to be installed as part of said plan to ensure the safety of the miners.
19. The terms and conditions of this Proposed Decision and Order will not apply in a panel during the time period from completion of the development mining of the two-entry longwall panel until the beginning of the longwall equipment set-up activities, provided the conveyor belt in the two-entry panel is not energized. During this time period, all other mandatory standards will apply.
20. Prior to implementing the Proposed Decision and Order, an inspection shall be conducted by MSHA to ensure that the terms and conditions of this Proposed Decision and Order have been complied with and that the miners have been trained in proper evacuation procedures, including instructions and drills in evacuation and instructions in precautions to be taken for escape through smoke.
21. Within 60 days after this Proposed Decision and Order becomes final, the Petitioner shall submit proposed revisions for its approved 30 CFR Part 48 training plan to the District Manager. These proposed revisions shall specify initial and refresher training regarding compliance with the conditions specified by the Proposed Decision and Order.
Any party to this action desiring a hearing on this matter must file in accordance with 30 CFR 44.14, within 30 days. The request for hearing must be filed with the Administrator for Coal Mine Safety and Health, 4015 Wilson Boulevard, Arlington, Virginia 22203.
If a hearing is requested, the request shall contain a concise summary of position on the issues of fact or law desired to be raised by the party requesting the hearing, including specific objections to the proposed decision. A party other than Petitioner who has requested a hearing shall also comment upon all issues of fact or law presented in the petition, and any party to this action requesting a hearing may indicate a desired hearing site. If no request for a hearing is filed within 30 days after service thereof, the Decision and Order will become final and must be posted by the operator on the mine bulletin board at the mine.
_________________________________
Robert A. Elam
Deputy Administrator
for Coal Mine Safety and Health
|
