Coastal Coal - West Virginia, LLC
Mine #4A East
I.D. No. 46-07125
Docket No. M-2002-038-C
30 CFR 75.1002
On April 3, 2002, Coastal Coal - West Virginia LLC (Coastal) filed a petition seeking a modification of the application of 30 CFR 75.1002 to its Mine #4A East located in Webster County, West Virginia. The Petitioner alleges that the alternative method outlined in the petition will at all times guarantee no less than the same measure of protection afforded by the standard.
MSHA personnel conducted an investigation of the petition and filed a report of their findings and recommendations with the Administrator for Coal Mine Safety and Health. After a careful review of the entire record, including the petition, MSHA's investigative report and recommendations, this Proposed Decision and Order is issued.
The alternative method proposed by the Petitioner will at all times guarantee no less than the same measure of protection afforded the miners under 30 CFR 75.1002.
On the basis of the petition and the findings of MSHA's investigation, Coastal Coal - West Virginia, LLC is granted a modification of the application of 30 CFR 75.1002 to its Mine #4A East.
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 Coastal Coal - West Virginia, LLC's Petition for Modification of the application of 30 CFR 75.1002 in the Mine #4A East is hereby:
GRANTED, for the 2,400-volt continuous miners used, conditioned upon compliance with the following terms and conditions:
- The portable transformer that supplies power to the
995-volt tramming motors, essential hydraulic pump motors and control
circuitry on the continuous miner when the miner is trammed into, out of, or
around the mine must not be used to back-feed the 2,400-volt circuits on the
continuous miner. The portable transformer used to power the continuous miner
for tramming must not be moved when energized.
- The nominal voltage of power circuits shall not
exceed 2,400 volts.
- The nominal voltage of the control circuits shall not
exceed 120 volts.
- The ground-fault current shall be limited by a
neutral grounding resistor to not more than 0.5 ampere. Should the 0.5 ampere
current limit create problems locating a ground-fault in the high-voltage
trailing cable, the neutral grounding resistor may be adjusted to limit the
ground-fault current to not more than 1.0 ampere. The 1.0 ampere setting
cannot be implemented until MSHA inspects the neutral grounding resistor and
determines that the neutral grounding resistor and all ground-fault relays are
properly adjusted to provide proper protection. Current transformers used for
the ground-fault protection shall be the single-window type and shall be
installed to encircle all three-phase conductors.
- High-voltage circuits shall be protected against
short-circuits, overloads, ground faults, and undervoltage by a circuit
interrupting device of adequate interrupting capacity.
- The trailing cable for the 2,400-volt continuous
miner circuit shall be provided with instantaneous ground-fault protection set
at not more than 0.125 ampere. The ground-fault protection device shall be
equipped with an impedance-measuring feature, "Look-Ahead" circuit, to guard
against closing the circuit breaker on a circuit that has an existing
ground-fault condition.
- The neutral grounding resistor shall be provided with
backup ground-fault protection that will deenergize the primary of the
transformer if a ground fault occurs with the neutral grounding resistor open.
This protection shall be set at 40 percent of the maximum voltage that could
appear across the neutral grounding resistor during a ground fault. A time
delay for coordination with downstream ground-fault protection devices shall
be set at the lowest practical value that permits reliable coordination;
however, in no case shall the time delay exceed 0.25 second.
- Each ground-fault current device shall be provided
with a test circuit that will inject a current of 50 percent or less of the
current rating of the grounding resistor and cause each corresponding circuit-
interrupting device to open. The test circuit shall not subject the equipment
to an actual phase-to-ground fault condition.
- Each ground-fault test circuit shall be actuated
weekly by a person qualified in accordance with 30 CFR 75.153 to perform
electrical work on all circuits and equipment and this qualified person shall
also activate the emergency stop button and verify that the corresponding
devices open. This qualified person shall also activate weekly the
ground-monitor circuit for the high-voltage trailing cable and verify that the
circuit-interrupting device for the high-voltage continuous miner opens and
deenergizes the high voltage trailing cable that supplies power to the
continuous miner.
- The neutral grounding resistor shall be provided with
protection that will deenergize the incoming high-voltage circuit supplying power to the power center if the grounding resistor is subjected to a sustained
ground-fault. The thermal protection shall operate at
either 50 percent of the maximum temperature rise of
the grounding resistor, or 1500 C (3020 F),
whichever is less. The thermal protection shall not be dependent upon control
power and may consist of a current transformer and overcurrent relay in the
grounding resistor circuit.
- The trailing cable for the continuous miner shall be
provided with instantaneous short-circuit protection set at no more than the
setting(s) specified for each conductor size and cable length listed in the
continuous miner approval documentation or 75 percent of the minimum
phase-to-phase short-circuit current available at the continuous miner,
whichever is less.
The short-circuit protective device shall contain no intentional time delay and shall be based on the maximum asymmetrical starting current or have a time delay of no more than 0.05 seconds and be based on the maximum symmetrical starting current. The time delay settings shall not exceed the settings specified in the approval documentation.
- All components that provide short-circuit protection
shall have an interruption rating in accordance with maximum short-circuit
currents available inby that circuit interrupting device(s), and shall be
rated for the maximum phase-to-phase voltage of the circuit.
- The miner high-voltage trailing cable shall be
provided with undervoltage protection which operates on loss of voltage to
cause and maintain the interruption of power to the circuit to prevent
automatic restarting of the equipment.
- Circuit interrupting devices shall not reclose
automatically.
- The high-voltage trailing cable shall be guarded or
hung on well installed insulators. The requirement of guarding or hanging high
voltage trailing cable does not preclude the temporary lacing of slack cable
resulting from a power center move onto a sled or into a crosscut. That sled
or crosscut may be located somewhere between the power center and the last
open crosscut and be positioned and barricaded against vehicular or foot
travel and equipped with high-voltage warning signs.
- If guarded, guarding made of grounded metal
or nonconductive flame-resistant conduit material shall be provided to
minimize the possibility of miners contacting the high-voltage trailing
cable and to protect the high-voltage trailing cable from damage. The
guarding must extend outby from the high-voltage miner cable entrance gland
for a distance of a minimum of 10 feet outby the high-voltage trailing cable
strain clamp. In addition, the high-voltage trailing cable shall be guarded
at the following locations:
- At the power center for a distance of 10 feet;
and
- At any location on the working section where it may be damaged by moving equipment.
- At the power center for a distance of 10 feet;
and
- If hung, the high-voltage trailing cable shall be
installed on well-installed insulators from the power center to the last
open crosscut during advance mining and not more than 150 feet from any
pillar workings during retreat or second mining.
- When other equipment cables must cross the portion
of continuous miner high-voltage cable located in
or inby the last open crosscut, the high-voltage
trailing cable shall be either suspended from the
mine roof, suspended a minimum of six and one half
(6- ½) feet above the mine floor, or the cable
shall be protected by a cable crossover. Cable
crossovers shall not be routinely used. Their use
shall be reserved for infrequent instances where
multiple machine cables are crossed/entangled and must be reordered or for
emergency egress while extracting a pillar. If used, cable crossovers must:
- Have a minimum length of 33 inches;
- Have a minimum width of 17 inches;
- Have a minimum height of 3 inches;
- Have a cable placement area that is a minimum of
two and one half inches (2½") high by four and one quarter inches (4
1/4") wide;
- Use nonconductive material for the crossover; and
- Use material for the crossover that is colored a
highly distinctive color. The color black shall not be used.
- Have a minimum compressive strength of 6400 pounds per square inch.
- Have a minimum length of 33 inches;
- If guarded, guarding made of grounded metal
or nonconductive flame-resistant conduit material shall be provided to
minimize the possibility of miners contacting the high-voltage trailing
cable and to protect the high-voltage trailing cable from damage. The
guarding must extend outby from the high-voltage miner cable entrance gland
for a distance of a minimum of 10 feet outby the high-voltage trailing cable
strain clamp. In addition, the high-voltage trailing cable shall be guarded
at the following locations:
- The high-voltage trailing cable shall be designed
as follows:
- The high-voltage trailing cable shall be designed
to have 100 percent semi-conductor tape shielding or metallic braid
shielding coverage over each power conductor;
- The protective jacket shall consist of two
layers, an outer and inner protective jacket insulation;
- The color black shall not be used for either of
the two protective insulation layers; and,
- The inner-most layer of the two layered insulation jackets shall be colored a distinctive color from the outer jacket to allow easy recognition of damaged areas to the outer protective jacket insulation.
- The high-voltage trailing cable shall be designed
to have 100 percent semi-conductor tape shielding or metallic braid
shielding coverage over each power conductor;
- Splices and repairs to high-voltage trailing cables
shall comply with the following:
- Splices and repairs in high-voltage trailing
cables shall be made only by a qualified person as provided in 30 CFR
75.153 who has received hands-on training in the proper methods of
splicing and repairing these high-voltage trailing cables.
- Each splice or repair made underground in a
high-voltage trailing cable shall be made in a workman-like manner and in
accordance with the instructions of the manufacturer of the repair
materials, and as provided for in 30 CFR 75.810. The outer jacket of each
splice or repair shall be vulcanized with flame-resistant material or made
with a kit that has been accepted by MSHA as flame-resistant. Each splice or
major repair shall be made so that all cable components are replaced with
similar components. Repairs are considered major if there is any damage to
the metallic shielding, semi-conductor tape, inner conductor insulation, or
conductors. Minor repairs to the outer cable jacket may be made by using
tape accepted by MSHA as flame-resistant.
- Temporary and/or permanent tape-type splices in any
high-voltage trailing cable are prohibited. Only MSHA approved permanent
splice kits containing outer jacket boots, either heat and/or cold
application types, will be acceptable.
- Only four (4) permanent splices will be allowed at any one time for the portion of the high-voltage trailing cable that extends from the continuous miner outby for a distance of 300 feet. Splicing of the high-voltage trailing cable within 35 feet of the continuous miner is prohibited.
- Splices and repairs in high-voltage trailing
cables shall be made only by a qualified person as provided in 30 CFR
75.153 who has received hands-on training in the proper methods of
splicing and repairing these high-voltage trailing cables.
- Once each day a qualified person, as required by 30
CFR 75.153, shall inspect the entire length of the high-voltage trailing cable
from the section power center to the continuous miner. The inspection shall
include inspecting the integrity of the outer jacket of the high-voltage
trailing cable, all permanent splices, and those areas where additional
protective guarding is required. Any defects detected during such inspection
shall be immediately corrected. Once each production shift a person designated
by the operator shall inspect the entire length of the high-voltage trailing
cable to check the outer jacket for damage.
- The section power center shall be equipped with a
main disconnecting device installed to deenergize the primary of all
transformers supplying high-voltage power when the device is in the open
position. The high-voltage trailing cable extending to section equipment shall
be equipped with a disconnecting device and/or cable couplers installed to
deenergize the trailing cable when the device is in the open position.
- The compartment for the disconnecting device and the
compartment(s) that provide access to energized conductors or parts shall be
provided with caution label(s) to warn miners against entering the
compartment(s) before deenergizing and grounding the high-voltage circuits.
Before any work is performed inside any compartment(s) all capacitor storage
devices located within the compartment(s) shall be discharged and grounded. A
grounding device for discharging capacitor storage devices shall be provided
and stored in a dry location. A label shall be installed and maintained at the
grounding device storage location to readily identify its location.
- Disconnecting devices shall comply with the following:
- Disconnecting devices shall be rated for the
maximum phase-to-phase voltage of the circuit in which they are installed,
and shall be rated for the full load current of the circuit that is
supplied power through the device.
- Each disconnecting device shall be designed,
installed and maintained so that:
- It can be determined by visual observation that
the contacts are open without removing any cover;
- All load power conductors can be grounded when
the device is in the "open" position;
- The device can be locked in the "open"
position; and,
- If a cable coupler is used as the disconnecting device, connect the load power conductor in the high-voltage cable to the grounded frame of the enclosure by means of the grounding receptacle provided and place the dust cover on the enclosure from which the cable was disconnected.
- It can be determined by visual observation that
the contacts are open without removing any cover;
- Disconnecting devices, except those installed in
explosion-proof enclosures, shall be capable of interrupting the full-load
current of the circuit or designed and installed to cause the current to
be interrupted automatically prior to the opening of the contacts of the
device.
- Disconnecting devices installed in
explosion-proof enclosures shall be maintained in accordance with the
approval documentation.
- A sign shall be located near each visible disconnecting device which clearly identifies the circuit it disconnects.
- Disconnecting devices shall be rated for the
maximum phase-to-phase voltage of the circuit in which they are installed,
and shall be rated for the full load current of the circuit that is
supplied power through the device.
- The control circuit for each power center shall be
interlocked with the primary disconnecting device in the power center so
that:
- When the primary disconnecting device is in the
"open" position, the control circuit can only be powered through an
auxiliary switch in the test position; and,
- When the primary disconnecting device is in the "closed" position, the control circuit can be powered only through an auxiliary switch in the normal position.
- When the primary disconnecting device is in the
"open" position, the control circuit can only be powered through an
auxiliary switch in the test position; and,
- Cover interlock switch(s) and an emergency stop switch
shall be provided and maintained on the section power center to automatically
deenergize the incoming high-voltage power circuit to the section power center
in the event of an emergency or when a cover of the power center that provides
access to energized high-voltage conductors or parts is removed. Cover interlock
switch(s) shall be provided and maintained on the high-voltage continuous mining
machine to automatically deenergize the incoming high-voltage power circuit to
the continuous miner when a cover of the continuous miner that provides access
to energized high-voltage conductors or parts is removed.
- The control circuit of each 2,400-volt output circuit shall be located in a properly deadfronted compartment. The deadfronted compartment shall be arranged so that miners can trouble shoot or test in the control circuit compartment(s) without being exposed to energized high-voltage conductors or parts.
- Barriers shall be provided and covers shall be arranged
so that miners can work in the 2, 400-volt section of the power center without
being exposed to any energized conductors or parts that exceed 150 volts RMS,
including capacitors, when the primary disconnecting switch is in the "open and
grounded" position.
Barriers shall be provided and covers shall be arranged so that miners can work in the control compartments of the power center without being exposed to energized conductors or parts that exceed 150 volts RMS regardless of the position of the main disconnect switch.
- Barriers shall be provided and covers shall be arranged
so that miners can test and troubleshoot low- and
medium-voltage circuits in the power center without
being exposed to any energized high-voltage conductors
or parts, including capacitors, regardless of the
position of the primary disconnecting switch.
Barriers shall be provided and covers shall be arranged so that miners can test and troubleshoot low- and medium-voltage circuits in the continuous mining machine with out being exposed to any energized high-voltage conductors or parts regardless of the position of the miner disconnect switch.
- Trouble-shooting and testing of energized circuits shall be limited to the following:
- Trouble-shooting and testing of energized circuits shall be conducted only on low- and medium-voltage circuits; and,
- Trouble-shooting and testing of energized low- or medium-voltage circuits and equipment shall be performed only by persons qualified in accordance with 30 CFR 75.153 to perform electrical work on all circuits and these persons shall wear rubber insulating gloves rated at least for the nominal voltage of the low- or medium-voltage circuit or equipment while trouble-shooting or testing.
- Trouble-shooting and testing of energized circuits shall be conducted only on low- and medium-voltage circuits; and,
- Trouble-shooting and testing of low- and
medium-voltage circuits and equipment shall only be performed to determine
voltage and current levels or waveforms.
- A ground-fault indicator light shall be installed and
maintained on the continuous miner that can be readily observed by the miner
operator from any location that the continuous miner can be operated. When the
ground-fault indicator light indicates a ground-fault on any of the ungrounded
"Y" 995-volt circuits that supply three-phase power to the left and right hand
gathering head motors, dust collector motor or pump motor or the ungrounded
"Y" 270-volt circuit that supplies three-phase power to the SCR panel
assemblies for the left and right traction motors, the following maintenance
procedures shall be implemented immediately;
- The continuous miner shall be trammed only to a
well supported area; and,
- The ground-fault shall be located and corrected prior to the continuous miner being placed back into operation.
A test circuit for the ground-fault indicator system shall be provided and a functional test of the system shall be conducted at the beginning of each production shift. The ground-fault indicator system shall be wired in a manner that prevents by-passing this safety feature.
- The continuous miner shall be trammed only to a
well supported area; and,
- Each output circuit from the section power center shall
be equipped with a MSHA-approved
ground-wire monitoring system. Each receptacle shall be interlocked with the
ground wire monitor circuit such that the circuit interrupting device will
open when the trailing cable is disconnected from the power center receptacle.
- Each ground-wire monitor and associated circuits
shall be examined and tested at least weekly to verify proper operation and
to verify that they will cause their circuit interrupting device to open.
- Before any electrical work (including testing,
troubleshooting, and fault finding) is performed inside any compartment of the
section power center containing high-voltage components or parts, including
capacitors, person(s) qualified to perform work on all circuits (as provided
for in 30 CFR 75.153) shall:
- Determine that the contacts of the primary
disconnecting device in the power center are open and grounded;
- Lock-out and tag the primary disconnecting device;
and,
- Assure that all 2,400-volt capacitors have been discharged and grounded.
- Determine that the contacts of the primary
disconnecting device in the power center are open and grounded;
- Before any electrical work (including testing,
troubleshooting, or fault finding) is performed on the high-voltage trailing
cable, a qualified person (as provided for in 30 CFR 75.153) shall:
- Determine that the contacts of the primary
disconnecting devicesare "open" and all affected conductors are "grounded"
or when a cable coupler is used as a disconnecting device, determine that
the high-voltage trailing cable is deenergized and disconnected from the
enclosure;
- Lockout and tag the disconnecting device in
this position; and,
- If a cable coupler is used as the disconnecting device, connect the phase conductors in the high-voltage trailing cable to the grounded section power center frame by means of the grounding receptacle provided and place a dust cover on the enclosure receptacle from which the cable was disconnected.
- Determine that the contacts of the primary
disconnecting devicesare "open" and all affected conductors are "grounded"
or when a cable coupler is used as a disconnecting device, determine that
the high-voltage trailing cable is deenergized and disconnected from the
enclosure;
- Before any electrical work (including testing,
troubleshooting, or fault finding) is performed on the high-voltage continuous
miner, a qualified person (as provided for in 30 CFR 75.153) shall:
- Determine that the contacts of the machine disconnecting device are "open" and all affected conductors are "grounded"; and,
- Lockout and tag the disconnecting device in this position.
- Each person performing work on circuit(s) or
equipment shall place his name and a brief description of work to be
performed on the tag that is attached to the visual disconnecting device.
- Each padlock(s) and tag shall be removed only by the
person(s) who installed them, except that if that
person is unavailable, the lock and tag may be removed
by a person authorized by the operator. The authorized
person must be qualified to perform electrical work on
all circuits and equipment, as required by 30 CFR 75.153, and must determine that the
removal of the lock and tag does not pose a hazard to miners.
- During normal operations of making unit power
moves, either advancement or retreat or when it becomes necessary to move
additional slack high-voltage trailing cable from the power center to the
last open crosscut, the high-voltage trailing cable shall be deenergized,
locked-out and tagged, prior to the high-voltage trailing cable being
handled. The input high-voltage power cable shall be deenergized and
locked-out and tagged prior to a power center move being made.
- During mining operations, the 2,400-volt continuous
miner trailing cable shall only be connected to the
working section power center. When the high-voltage
cable inadvertently comes out of a hanger between the
power center and the last open crosscut, the cable may
be reinstalled in the hanger while energized provided
the person handling the cable is wearing properly
tested, Class 1, insulated gloves (minimum 7,500-volts
rating).
With the exception of the continuous miner trailing cable, handling of any other energized high-voltage power cable in the mine is prohibited. - All electrical protective equipment used to handle
energized high-voltage trailing cables shall be provided by the mine
operator.
- Miners shall not handle or move the energized high-voltage trailing cable located in or inby the last open crosscut unless they are wearing properly tested, Class 1 rated insulated gloves (minimum 7,500-volts rating).
- When wet and muddy conditions exist on the operating section, other electrical protective equipment such as, tongs or hotsticks, shall be used in conjunction with the properly rated insulated gloves while handling the energized high-voltage trailing cable located inby the section power center.
- Electrical personal protective equipment shall be visually inspected before each use for signs of damage or defects.
- Rubber gloves shall be field air tested before each use to ensure their effectiveness. Damaged or defective protective equipment shall not be used and shall be destroyed immediately and removed from the mine by the completion of the shift on which the equipment was found to be defective. Personal protective equipment shall be electrically tested and stored in accordance with the schedule listed in 30 CFR 75.705-8. These tests are to be conducted as described in a nationally recognized standard, such as ASTM 496-91.
- The petitioner's alternative method shall not be implemented until all personnel who perform maintenance on the high-voltage continuous miner system have received training in high-voltage safety, testing and maintenance procedures. Also, all personnel who work in proximity of the high-voltage equipment or who move high-voltage equipment or cables shall be trained in high-voltage safety procedures. The training shall be "hands on" specific, and shall be incorporated into the Part 48 training plan and in the annual refresher training plan for the mine. A record of this training shall be maintained and made available to authorized MSHA representatives and to other interested parties.
- The high-voltage continuous mining system shall not be put into service until after MSHA has inspected the equipment and determined that it is in compliance with all the above terms and conditions.
- 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 Coal Mine Safety and Health District Manager in which the District the mine is located. These proposed revisions shall include, but are not limited to, task training, hazard training, specialized training for qualified persons under 30 CFR 75.153, and annual refresher training. In addition the following shall be adopted:
- Safety precautions for the handling and use of high-voltage trailing cables, for all miners assigned to work in the area of the high-voltage trailing cable; and
- Specialized training for qualified electricians that will be required to repair, maintain and/or trouble-shoot the high-voltage trailing cable or equipment. This training shall focus on the requirements of this modification.
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.
_________________________________________
Michael J. Lawless
Deputy Administrator
for Coal Mine Safety and Health
