[Federal Register Volume 78, Number 138 (Thursday, July 18, 2013)]
[Notices]
[Pages 42977-42982]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-17202]


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DEPARTMENT OF LABOR

Mine Safety and Health Administration


Petitions for Modification of Application of Existing Mandatory 
Safety Standards

AGENCY: Mine Safety and Health Administration, Labor.

ACTION: Notice.

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SUMMARY: Section 101(c) of the Federal Mine Safety and Health Act of 
1977 and 30 CFR part 44 govern the application, processing, and 
disposition of petitions for modification. This notice is a summary of 
petitions for modification submitted to the Mine Safety and Health 
Administration (MSHA) by the parties listed below to modify the 
application of existing mandatory safety standards codified in Title 30 
of the Code of Federal Regulations.

DATES: All comments on the petitions must be received by the Office of 
Standards, Regulations and Variances on or before August 19, 2013.

ADDRESSES: You may submit your comments, identified by ``docket 
number'' on the subject line, by any of the following methods:
    1. Electronic Mail: [email protected]. Include the docket 
number of the petition in the subject line of the message.
    2. Facsimile: 202-693-9441.
    3. Regular Mail or Hand Delivery: MSHA, Office of Standards, 
Regulations and Variances, 1100 Wilson Boulevard, Room 2350, Arlington, 
Virginia 22209-3939, Attention: George F. Triebsch, Director, Office of 
Standards, Regulations and Variances. Persons delivering documents are 
required to check in at the receptionist's desk on the 21st floor. 
Individuals may inspect copies of the petitions and comments during 
normal business hours at the address listed above.
    MSHA will consider only comments postmarked by the U.S. Postal 
Service or proof of delivery from another delivery service such as UPS 
or Federal Express on or before the deadline for comments.

FOR FURTHER INFORMATION CONTACT: Barbara Barron, Office of Standards, 
Regulations and Variances at 202-693-

[[Page 42978]]

9447 (Voice), [email protected] (Email), or 202-693-9441 
(Facsimile). [These are not toll-free numbers.]

SUPPLEMENTARY INFORMATION: 

I. Background

    Section 101(c) of the Federal Mine Safety and Health Act of 1977 
(Mine Act) allows the mine operator or representative of miners to file 
a petition to modify the application of any mandatory safety standard 
to a coal or other mine if the Secretary of Labor determines that:
    (1) An alternative method of achieving the result of such standard 
exists which will at all times guarantee no less than the same measure 
of protection afforded the miners of such mine by such standard; or
    (2) That the application of such standard to such mine will result 
in a diminution of safety to the miners in such mine.
    In addition, the regulations at 30 CFR 44.10 and 44.11 establish 
the requirements and procedures for filing petitions for modification.

II. Petitions for Modification

    Docket No: M-2013-008-M.
    Petitioner: U.S. Silver Idaho, Inc., 1801 California Street, Suite 
4900, Denver, Colorado 80202.
    Mine: Galena Mine, MSHA I.D. No. 10-00082, located in Shoshone 
County, Idaho.
    Regulation Affected: 30 CFR 57.14106(a) (Falling object 
protection).
    Modification Request: The petitioner requests a modification of the 
existing standard to permit the use of Load, Haul, Dump (LHD) utility 
vehicles underground without falling object protection structures 
(FOPS) because it would result in a diminution of safety to the miners 
affected.
    a. Both the mining method and the ground control at the Galena mine 
are such that there is no increased hazard from falling objects.
    (1) The Galena mine complex hosts a wide range of rock conditions. 
To ensure a safe work environment, the company has employed a 
combination of good mining practices, rock bolting fixtures, surface 
support, backfill, and timber in its ground support plan. Hence, the 
LHDs are never operated under unsupported ground.
    (2) The minimum ground support standards in the areas where the 
subject LHDs are used in the Galena mine are as follows: in areas where 
overhand cut and fill is used, the back and ribs are supported with a 
minimum of 4-foot bolts and holey boards or monster mats. Support used 
on the ribs include a combination of bolts, holey boards, mats, stulls, 
and screen. Additional rib support of 6-foot rebar on 6-foot spacing is 
also used in certain areas. Additional surface support such as wire 
mesh, poly mesh, mats, and shotcrete is also installed when conditions 
warrant.
    (3) In areas where underhand cut and fill is used, the back must 
have mesh across the cement fill/rock contacts, which is attached by 
plates over the exposed 6-foot rebar bolts. A minimum of 4-foot split 
sets on 3-foot centers with wire mesh is used for rib support. Wire 
mesh is installed with adequate overlap and to within 5 feet of the 
sill. Where warranted, additional surface support such as wire mesh, 
poly mesh, mats, and shotcrete can be installed.
    (4) In areas of vertical development, the back is supported with a 
minimum of 4-foot bolts and holey boards or monster mats. The hanging 
and footwall is supported with a minimum of 4-foot bolts and one row of 
mats per timber set. Raise timber is installed with a minimum of 12 
inches of heading between the cap and wall.
    (5) The mine's current practice is to not exceed 11 feet in cut 
height to facilitate hand-held jack leg drilling and bolt installation 
safely and productively.
    b. There have been no documented falling object incidents at the 
Galena mine.
    (1) Mine policies at the Galena mine prohibit miners from working 
under unsupported ground.
    (2) No miner working in an LHD without FOPS has been injured by 
falling material.
    c. Rock burst potential at the Galena mine does not mean there is 
an increased hazard of falling objects.
    (1) While geological conditions at the Galena mine may make the 
mine susceptible to rock bursts, rock bursts are not falling object 
events. They more typically involve the sudden expulsion of material 
from the ribs. Because of the more or less horizontal nature of that 
expulsion, FOPS would provide little or no protection. Moreover, rock 
bursts typically occur at blasting time, after all personnel have 
exited active headings. Seismic activities at the Galena mine are 
actively monitored and a rock burst control plan is in place as 
required by 30 CFR 57.3461.
    (2) This plan is specifically designed to reduce the occurrence of 
rock bursts, monitor procedures where detection methods are used, and 
provide additional measures to minimize exposure of persons to rock 
bursts, such as stress shadowing and other mining techniques.
    d. Complying with 30 CFR 57.14106(a) would subject miners to 
greater hazards than they are subjected to under current conditions.
    e. Significant changes to the ground control plan at the Galena 
mine would need to be made to accommodate clearance for the FOPS.
    f. Enlarging the heading height at the Galena mine exposes more rib 
height, which reduces the stope ribs' structural stability.
    (1) Sound geotechnical principles dictate that ground support 
requirements are directly linked to the span of the excavation; this 
applies to both lateral and vertical spans. Greater spans require 
longer fixtures more closely spaced to overcome the forces and loads 
that the spans are subjected to. Successful narrow vein mining methods 
are dependent upon minimizing spans and the inherent risks associated 
with exceeding critical dimensions.
    (2) Requiring the use of FOPS at the Galena mine will dictate wider 
and higher excavations to accommodate the FOPS. LHD operators will be 
subjected to exposures and hazards not faced today, and even greater 
exposure will exist for the personnel on the ground installing and 
maintaining the ground support and performing other essential tasks. A 
typical mining cycle in a mechanized area of the Galena mine only 
requires about 2 hours of the available work cycle; the remainder of 
the cycle is consumed by installing and maintaining the ground support, 
advancing utilities, and drilling and charging the next advance 
sequence. This work is performed from the ground with hand-held tools. 
All risks and exposures previously detailed for the LHD operators will 
be faced by the ground miner for an even greater period of time. 
Additionally, a miner's ability to adequately scale and provide for 
proper rock bolting processes will be negatively impacted by the 
higher, wider spans.
    (3) Hanging wall stability in the Galena mine is most significantly 
influenced by two main factors: The geologic composition of the wall 
rock, and the height and attitude of the hanging wall. The higher and 
flatter the hanging wall, the greater the likelihood of deterioration 
or failure as a result of the effects of gravity, as well as the 
lateral stresses present that provide for rock burst potential.
    (4) Mining higher and/or wider increases cycle times, increases 
exposure, and radically influences stability. Techniques and procedures 
have been developed at the Galena mine that provide for safe mineral 
extraction on a sustained basis, and minimize the deterioration and 
failure potential of

[[Page 42979]]

hanging walls in the ore producing areas. The positive effects of these 
techniques and procedures that have proved effective over time will be 
negated by creating wider and higher excavations.
    g. FOPS will become entangled with existing ground support and 
compromise the existing ground control.
    (1) Backs in the Galena mine complex vary in terms of height and 
the type of ground support used. Currently the LHDs used in the Galena 
mine are being used in stopes where wire mesh, roof bolts, cables, 
split sets, holey boards, mats, stulls, and screens are used. The 
primary supports used to address ground control in the area often 
protrude from the back and ribs and are vulnerable to damage by moving 
equipment. If the FOPS were to get caught in this material, not only 
would ground support be compromised if the FOPS inadvertently dislodged 
any of these support fixtures, but the equipment operator could also 
experience injury. In addition, the LHD itself could be damaged if 
there is impact with the rib or with ground support fixtures protruding 
from the rib.
    (2) The Galena mine operates a number of other LHDs for which there 
are no original equipment manufacturer (OEM) FOPS available. This is 
significant because for those units where no OEM FOPS exists, there may 
not be adequate room to attach such a structure without impinging into 
the operator's compartment in such a way as to either increase the 
likelihood of injury or severely impede visibility.
    h. FOPS would only provide protection from falling objects during a 
small fraction of the stoping cycle. Currently miners at the Galena 
mine spend 1-2 hours in the LHD mucking in each stoping cycle. The rest 
of the time the miners are on foot or using other equipment without 
FOPS, and those employees are considered to be safe enough with only 
personal protective equipment to protect them (for example, a miner 
bolting with a jackleg, loading a round, preparing for backfill, etc.). 
When considering that these miners are working without FOPS protection 
for most of their shifts, requiring FOPS on LHDs certainly flies in the 
face of logic.
    i. The FOPS mounting hardware creates pinch points. The most 
dangerous pinch points on an LHD are in and around the articulation 
joint. The operator's cab is positioned immediately adjacent to the 
articulation, and operators must be very cautious to avoid this hazard. 
Clearances in the articulation area are small without FOPS installed 
and even more so with the canopy on. On the 2cy LHDs, a post must be 
installed to mount the canopy creating a pinch point hazard.
    j. FOPS will reduce visibility to operators.
    (1) Visibility is a key operational safety factor in operating any 
type of heavy machinery. This is particularly true in mechanized 
narrow-vein mining as practiced at the Galena mine. While operating an 
LHD with FOPS installed, the operator's sight lines become obstructed, 
increasing risk to the operator and to others working in the area.
    (2) Miners at the Galena mine have stated they are opposed to the 
addition of FOPS to the LHDs because of the decrease of visibility to 
equipment operators. The reduction of line-of-sight visibility for the 
operator increases the potential for ``struck by'' injuries to miners 
traveling or working in the vicinity of the equipment. Additionally, to 
alleviate the limited visibility, the miners may be inclined to lean 
out of the side of the equipment, which not only negates any benefit of 
the canopy, but also increases the risk for head and neck injuries.
    k. FOPS will decrease operator space. The LHD operators' cabs at 
the Galena mine are already cramped, and will become even more cramped 
with FOPS installed. Some experienced operators and valued employees 
will no longer be able to operate the LHDs because they will not be 
able to fit in the cabs with FOPS installed. Overhead clearance within 
the operator's cab will likely be an issue as the LHD is subject to 
driving over potholes or rocks while tramming, causing the machine to 
bounce and the operators to hit their heads on the canopy.
    l. FOPS would inhibit rescue efforts if a rescue is required. 
Having FOPS installed on LHDs would greatly inhibit any rescue efforts 
that required an operator to be removed from the cab. If FOPS were 
installed on the LHDs, it would be difficult to extract the operator 
from the cab, as extrication gear is designed to work in a vertical 
orientation. It would also be difficult to transport victims out over 
an LHD stalled in a narrow stope heading, because the FOPS structure 
itself would impose a vertical obstruction midway along the length of 
the machine that a stretcher would have to be lifted over or around. 
Under the current operating conditions, there is adequate room to 
perform extrication without undue complications.
    m. The standard is not applicable to LHDs, which are low profile 
machines specifically designed for underground mining.
    (1) LHDs perform differently than front-end loaders. Front end-
loaders load trucks or hoppers. LHDs load themselves, generally by 
filling their bucket with muck, and then haul the loaded material over 
varying, often lengthy, distances to a dump point. In contrast, front-
end loaders fill their scoops or buckets multiple times for very short 
trips to haul trucks or other forms of equipment used purely for 
haulage. While both LHDs and front-end loaders have a hydraulically 
operated digging and lifting bucket on the front, the similarities 
between the two pieces of equipment end there.
    (2) The configuration of the two types of equipment is also 
strikingly different. In general, the operator's compartment of a 
front-end loader sits directly behind the scoop or bucket, facing 
forward to facilitate the equipment's sole mission of picking up 
multiple loads for the purpose of transferring them to haulage 
equipment. The operator's cab of a typical LHD is located in the middle 
of the machine to facilitate the equipment taking a single scoop or 
bucket load and then tramming in the opposite direction to a dump 
point. The midships positioning of the operator's cab on an LHD is 
intended to allow it to haul comparatively long distances in narrow 
areas where it is often unable to turn the machine around before 
initiating the haul. In this configuration the operator sits sideways, 
maximizing his ability to see where he is going when traveling in 
either direction.
    (3) Although the standard clearly applies to front-end loaders used 
in surface operations, when discussing the standard for backup alarms, 
30 CFR 57.14132 explicitly mentions and exempts load, haul, dump 
vehicles from that standard by name; [the back-up alarm/horn 
requirement] is applicable to surface mines and surface areas of 
underground mines only, because the construction of load, haul, dump 
vehicles generally used underground is such that the view to the rear 
is less likely to be obstructed. If 30 CFR 57.14106(a) was meant to 
apply to LHDs, the standard would have specifically referenced this 
type of equipment.
    The petitioner asserts that application of the existing standard 
would result in diminution of safety to the miners.
    Docket No: M-2013-009-M.
    Petitioner: Hecla Limited, 1801 California Street, Suite 4900, 
Denver, Colorado 80202.
    Mine: Lucky Friday Mine, MSHA I.D. No. 10-00088, located in 
Shoshone County, Idaho.
    Regulation Affected: 30 CFR 57.14106(a) (Falling object 
protection).

[[Page 42980]]

    Modification Request: The petitioner requests a modification of the 
existing standard to permit the use of Load, Haul, Dump (LHD) utility 
vehicles underground without falling object protection structures 
(FOPS) because it would result in a diminution of safety to the miners 
affected.
    a. Ground control at the Lucky Friday mine provides that there is 
no hazard from falling objects.
    (1) Based on Lucky Friday's extensive rock burst and ground control 
plans, the mines current practice is to not exceed 11 feet in cut 
height. This is a major design component that is based on years of 
stoping experience in the Lucky Friday mine. In the past, stopes mined 
higher than 11 feet on a cut exhibited less reliable rib conditions.
    (2) All of Lucky Friday's current stoping is being done by the 
underhand cut and fill method, which allows the operator to create an 
engineered stope backfill in a completed stope heading that becomes the 
back in the next cut taken below. Because the back is constructed to 
engineered specifications, there is high confidence of low risk of roof 
failure under the typical variations of wall rock geology encountered 
in the Lucky Friday mine.
    (3) As a result, stope crews (including LHD operators) work under 
cemented backfill that is substantially reinforced internally with 
bolts, wire, timbers, and cables as needed. The fill reaches a 
compressive strength of 200 psi within two to three days, at which time 
stope crews are allowed to reenter beneath the filled areas. The fill 
reaches strengths of 500 to 700 psi in 28 days. Wire mesh is attached 
to the ends of the bolts protruding below the cemented fill as the 
stoping crew mines the next cut. When conditions warrant, additional 
bolting is installed in the fill.
    b. There have been no documented falling object incidents at the 
Lucky Friday mine for 20 years. In the 1990's two miners were injured 
at the Lucky Friday mine when they were operating LHDs with FOPS under 
unsupported ground. Since that time, the mine's policies have been 
modified so that miners are prohibited from working under unsupported 
ground. No miner working in an LHD without FOPS has been injured by 
falling rock since the modification of this policy.
    c. Rock burst potential at the Lucky Friday mine does not mean 
there is an increased hazard of falling objects.
    (1) While geological conditions at the Lucky Friday mine may make 
the mine susceptible to rock bursts, rock bursts are not falling object 
events. They more typically involve the sudden expulsion of material 
from the ribs. Because of the more or less horizontal nature of that 
expulsion, FOPS would provide little or no protection. Moreover, rock 
bursts typically occur at blasting time, after all personnel have 
exited active headings. Seismic activities at the Lucky Friday mine are 
actively monitored and a rock burst control plan is in place as 
required by 30 CFR 57.3461.
    (2) This plan is specifically designed to reduce the occurrence of 
rock bursts, monitor procedures where detection methods are used, and 
provide additional measures to minimize exposure of persons to rock 
bursts, such as stress shadowing and other mining techniques.
    d. Complying with 30 CFR 57.14106(a) would subject miners to 
greater hazards than they are subjected to under current conditions.
    e. Significant changes to the ground control plan at the Lucky 
Friday mine would need to be made to accommodate clearance for the 
FOPS.
    f. Clearance at the Lucky Friday mine over the FOPS would become an 
issue.
    (1) At the stoping cut starts, there is generally adequate overhead 
clearance in a standard 11-foot-high cut to allow the LHD to operate 
without hitting the stope ventilation duct--a 30-inch vent bag. 
However, as the stope increases in length, or as stope headings branch 
off the main vein, a 42-inch vent bag is substituted on the fan end to 
reduce resistance in the duct and to keep airflow in the stope at 
acceptable volumes.
    (2) Reducing the size of the vent bag is not an option, as 
ventilation would be compromised. In the Lucky Friday's hot humid 
stoping environment it is essential to maximize ventilation flows so as 
to optimize performance of the air cooling systems. This performance 
must be achieved in concert with effective removal of air contaminants 
in the heading such as dust and diesel particulate matter, while 
providing adequate airflow for personnel and effective aspiration of 
diesel engines on the equipment. Any reduction in the size of the vent 
bag restricts airflow, negatively impacting ventilation performance in 
all of these areas. The 42-inch diameter vent bag now in use is the 
optimum size for the dimensions of the standard stopes.
    (3) If the use of FOPS on LHDs is required, the only viable 
solution to clearance problems is to enlarge the minimum heading size, 
which will result in increased risks to miners.
    g. Enlarging the heading heights exposes more rib height, which 
reduces the stope ribs' structure stability.
    (1) The Gold Hunter portion of the Lucky Friday mine is a deep 
mining operation located within the Wallace formation. The Wallace is 
composed primarily of vertical, thinly bedded, relatively weak and 
plastic argillites. Due to the depth of this mine, some degree of 
yielding of the rock around development headings and stopes is typical 
and expected. When the rock yields and delaminates, it loses much of 
its inherent strength. The orientation of the bedding, which is 
parallel to the veins, has a distinct impact on the type and depth of 
yielding around a tunnel or stope. In particular, excavations that are 
driven parallel to the bedding (which includes all stopes since bedding 
strikes parallel to the vein structure) will experience some degree of 
delamination or buckling of the thin argillite beds when subjected to 
the normal in situ stress state. The onset of significant buckling, as 
well as the depth of the resulting damage to rock in the walls, is 
roughly proportional to the height of exposed vertical walls in the 
stopes. Control of the yielding volume and deformation of stopes is 
achieved by two general design factors: (a) Minimizing opening size; 
and (b) application of ground support with sufficient density and 
length to maintain the yielded rock around the excavation.
    (2) Hecla's experience at the Gold Hunter portion of the Lucky 
Friday mine indicates that wall stability in stopes is particularly 
sensitive to wall height. For example, experience in the 550-14 stope 
(5500 Level) illustrates the issue fairly clearly. In 2010, mining in 
the 550-14 stope was initiated beneath the 15 stope, which was 
completed approximately 5 years prior. The initial plan was to leave a 
10-feet-high solid ore pillar beneath the 15 stope backfill during cut 
1 of 550-14 stope. This pillar was to be left since the 
backfill in the 15 stope had been in place for a long time and had 
deteriorated due to stope closure and water accumulation. As cut 
1 of the 14 stope was advanced, it became obvious that a 10-
feet-pillar height was insufficient and that 15 feet would be required. 
Cut 1 was stopped and cut 2 was initiated and 
advanced below the new backfill in cut 1 with the objective 
that it would be mined beyond the limits of cut 1 where the 
cut height would be increased from 10 feet to 15 feet, thus creating 
the desired 15-feet-pillar height. In the process of increasing the 
stope height from the standard 10 feet to the taller 15 feet, the wall 
of the stope failed at a height of 13 feet by buckling of beds. The 
failure, which was about 18 feet in length and 10 feet in height and 
approximately 6 feet to 8 feet in depth, occurred roughly

[[Page 42981]]

59 feet behind the advancing stope face. Currently, cut heights in 
stopes at the Gold Hunter are limited to 10 feet to minimize the 
potential of this type of failure.
    h. Keeping stope height to a minimum is fundamental to support 
strategy in potentially seismic conditions. Seismic conditions can 
sometimes occur at the Gold Hunter portion of the Lucky Friday mine 
primarily due to encountering preexisting, poorly oriented fault 
structures in proximity to the mining. A seismic event, resulting from 
slip on a fault structure will result in production of a seismic wave 
that transits through the rock mass and can impact the stopes. Damage 
from these events is largely the result of expulsion of disturbed 
(yielded) rock from the walls of the stopes. Since the back of stopes 
in the underhand mining method is engineered, damage has primarily been 
observed from the disturbed rock in the walls. Control of the expulsion 
of the pre-damaged wall is performed by limiting the height of the 
stopes and by installation of ground support, including heavy bolting 
and meshing. Increasing stope height results in greater depth of 
yielded/damaged rock in the walls. This greater depth of yielding 
creates a greater mass of weakened material that could potentially be 
ejected into a tunnel under seismic loading. The density and length of 
ground support required to dissipate the kinetic energy of this mass 
increases dramatically with the size of the failed zone. Thus, keeping 
the stope height to a minimum is fundamental to support strategy in 
potentially seismic conditions.
    i. To minimize the deterioration and failure potential of hanging 
walls in the ore producing areas, techniques and procedures developed 
at the Lucky Friday mine provide for safe mineral extraction on a 
sustained basis. The positive effects of these techniques and 
procedures that have proved effective over time will be negated by 
creating wider and higher excavations.
    j. FOPS will become entangled with existing ground support and 
compromise the existing ground control.
    (1) Backs in the Lucky Friday mine complex vary in terms of height 
and the type of ground support used. Currently the LHDs in the Lucky 
Friday mine are being used in stopes where wire mesh, roof bolts, 
cables, split sets, holey boards, mats, stulls and screens are used. 
The primary supports used to address ground control in the area often 
protrude from the back and ribs and are vulnerable to damage by moving 
equipment. If the FOPS were to get caught in this material, not only 
would ground support be compromised if the FOPS inadvertently dislodged 
any of these support fixtures, but the equipment operator could also 
experience injury. In addition, the LHD itself could be damaged if 
there is impact with the rib or with ground support fixtures protruding 
from the rib.
    (2) In a recent test at the Lucky Friday mine where an experienced 
LHD operator was asked to test performance of LHD equipment with FOPS, 
the LHD became trapped in a stope heading as the FOPS hooked on a split 
set that was installed to hold wire mesh against the rib. The operator 
was not trapped in the cab and was able to exit safely, but another LHD 
had to be brought in to extricate the trapped machine. A test of a LHD 
with a newly installed FOPS showed damage from the impacts with the 
stope rib after only minutes of operation.
    k. FOPS would only provide protection from falling objects during a 
small fraction of the stoping cycle. Currently miners at the Lucky 
Friday mine spend 1-2 hours in the LHD mucking in each stoping cycle. 
The rest of the time the miners are on foot or using other equipment 
without FOPS, and those employees are considered to be safe enough with 
only personal protective equipment to protect them (for example, a 
miner bolting with a jackleg, loading a round, preparing for backfill, 
etc.). When considering that these miners are working without FOPS 
protection for most of their shifts, requiring FOPS on LHDs certainly 
flies in the face of logic.
    l. The FOPS mounting hardware creates pinch points.
    (1) The most dangerous pinch points on an LHD are in and around the 
articulation joint. The operator's cab is positioned immediately 
adjacent to the articulation, and operators must be very cautious to 
avoid this hazard. Clearances in the articulation area are small 
without FOPS installed and even more so with the canopy on. On the 2cy 
LHD's, a post must be installed to mount the canopy creating a pinch 
point hazard.
    (2) On one occasion at the Lucky Friday mine (before the FOPS were 
removed in the 1990s), a miner lost his finger when his LHD started to 
tip over and he grabbed the FOPS canopy for support. His finger was 
caught between the canopy and stope rib and was amputated.
    m. FOPS will reduce visibility to operators.
    (1) Visibility is a key operational safety factor in operating any 
type of heavy machinery. This is particularly true in mechanized 
narrow-vein mining as practiced at the Lucky Friday mine. While 
operating an LHD with FOPS installed, the operator's sight lines become 
obstructed, increasing risk to the operator and to others working in 
the area.
    (2) Miners at the Lucky Friday mine have stated they are opposed to 
the addition of FOPS to the LHDs because of the decrease of visibility 
to equipment operators. The reduction of line-of-sight visibility for 
the operator increases the potential for ``struck by'' injuries to 
miners traveling or working in the vicinity of the equipment. 
Additionally, to alleviate the limited visibility, the miners may be 
inclined to lean out of the side of the equipment, which not only 
negates any benefit of the canopy, but also increases the risk for head 
and neck injuries.
    n. FOPS will decrease operator space. The LHD operators' cabs at 
the Lucky Friday mine are already cramped, and will become even more 
cramped with FOPS installed. Some experienced operators and valued 
employees will no longer be able to operate the LHDs because they will 
not be able to fit in the cabs with FOPS installed. Overhead clearance 
within the operator's cab will likely be an issue as the LHD is subject 
to driving over potholes or rocks while tramming, causing the machine 
to bounce and the operators to hit their heads on the canopy.
    o. FOPS would inhibit rescue efforts if a rescue is required. 
Having FOPS installed on LHDs would greatly inhibit any rescue efforts 
that required an operator to be removed from the cab. If FOPS were 
installed on the LHDs, it would be difficult to extract the operator 
from the cab, as extrication gear is designed to work in a vertical 
orientation. It would also be difficult to transport victims out over 
an LHD stalled in a narrow stope heading, because the FOPS structure 
itself would impose a vertical obstruction midway along the length of 
the machine that a stretcher would have to be lifted over or around. 
Under the current operating conditions, there is adequate room to 
perform extrication without undue complications.
    p. The standard is not applicable to LHDs, which are low profile 
machines specifically designed for underground mining.
    (1) LHDs perform differently than front-end loaders. Front end-
loaders load trucks or hoppers. LHDs load themselves, generally by 
filling their bucket with muck, and then haul the loaded material over 
varying, often lengthy, distances to a dump point. In contrast, front-
end loaders fill their scoops or buckets multiple times for

[[Page 42982]]

very short trips to haul trucks or other forms of equipment used purely 
for haulage. While both LHDs and front-end loaders have a hydraulically 
operated digging and lifting bucket on the front, the similarities 
between the two pieces of equipment end there.
    (2) The configuration of the two types of equipment is also 
strikingly different. In general, the operator's compartment of a 
front-end loader sits directly behind the scoop or bucket, facing 
forward to facilitate the equipment's sole mission of picking up 
multiple loads for the purpose of transferring them to haulage 
equipment. The operator's cab of a typical LHD is located in the middle 
of the machine to facilitate the equipment taking a single scoop or 
bucket load and then tramming in the opposite direction to a dump 
point. The midships positioning of the operator's cab on an LHD is 
intended to allow it to haul comparatively long distances in narrow 
areas where it is often unable to turn the machine around before 
initiating the haul. In this configuration the operator sits sideways, 
maximizing his ability to see where he is going when traveling in 
either direction.
    (3) Although the standard clearly applies to front-end loaders used 
in surface operations, when discussing the standard for backup alarms, 
30 CFR 57.14132 explicitly mentions and exempts load, haul, dump 
vehicles from that standard by name; [the back-up alarm/horn 
requirement] is applicable to surface mines and surface areas of 
underground mines only, because the construction of load, haul, dump 
vehicles generally used underground is such that the view to the rear 
is less likely to be obstructed. If 30 CFR 57.14106(a) was meant to 
apply to LHDs, the standard would have specifically referenced this 
type of equipment.
    The petitioner asserts that application of the existing standard 
would result in diminution of safety to the miners.

    Dated: July 12, 2013.
George F. Triebsch,
Director, Office of Standards, Regulations and Variances.
[FR Doc. 2013-17202 Filed 7-17-13; 8:45 am]
BILLING CODE 4510-43-P