805 KAR 5:070. Minimum requirements for roof
support and the roof control plan approval process.
RELATES TO: KRS 352.201
STATUTORY AUTHORITY: KRS 351.070(13)
NECESSITY, FUNCTION, AND CONFORMITY: KRS 352.201 requires
each underground coal mine to formulate and follow an approved roof control
plan. This proposed administrative regulation establishes those minimum
standards for roof support and the roof control plan approval process.
Section 1. Definitions. The definitions established
in KRS 351.010 and 352.010 shall apply to this administrative regulation, in
addition to those set out below:
(1) "Automated temporary roof support" or
"ATRS" means a mechanical device used to temporarily support the roof
while roof bolts are being installed.
(2) "Automated temporary roof support
system" means the devices and mechanisms - including the ATRS - used, and
methods followed by which ATRS is activated and set to support the roof.
(3) "Mining height" means the distance
between the bottom of the coal seam and the bottom of permanent mechanical roof
support, and specifically does not include or apply to the brushing of top or
bottom for construction work and to coal left unmined for purposes of providing
additional roof support.
(4) "Pillar recovery" means any reduction
in pillar size during retreat mining.
(5) "Roof control plan" means the plan
and its revisions which has been adopted by the licensee for support of the
mine roof and approved by the commissioner or his authorized representative
pursuant to KRS 352.201(1).
Section 2. Mining Methods. (1) The method of mining
shall not expose any person to hazards caused by excessive widths of rooms,
crosscuts and entries, or faulty pillar recovery methods. Pillar dimensions
shall be compatible with effective control of the roof, face, ribs and coal or
rock bursts.
(2) A sightline or other method of directional
control shall be used to maintain the projected direction of mining in entries,
rooms, crosscuts and pillar splits.
(3) A sidecut shall be started only from an area
that is supported in accordance with the roof control plan.
(4) A working face shall not be mined through into
an unsupported area of active workings, except when the unsupported area is
inaccessible.
(5) Additional roof support shall be installed
where:
(a) The width of the opening specified in the roof
control plan is exceeded by more than twelve (12) inches; and
(b) The distance over which the excessive width
exists is more than five (5) feet.
Section 3. Roof Bolting. (1) For roof bolts and
accessories addressed in American Society for Testing and Materials (ASTM, F
432-95), the licensee shall:
(a) Obtain a manufacturer's certification that the
material was manufactured and tested in accordance with the specifications of
ASTM; and
(b) Make this certification available to an
authorized representative of the commissioner.
(2) Roof bolts and accessories not addressed in the
material incorporated by reference may be used, if the use of those roof bolts
and accessories is approved by the commissioner or his authorized representative
based on:
(a) Demonstrations which show that the materials
have successfully supported the roof in an area of a coal mine with similar
strata, opening dimensions and roof stresses; or
(b) Tests which show the materials to be effective
for supporting the roof in an area of the affected mine which has strata,
opening dimensions and roof stresses similar to those in the area where the
roof bolts are to be used; during the test process, access to the test area
shall be limited to persons necessary to conduct the test.
(3) A bearing plate shall be firmly installed with
each roof bolt.
(4) A bearing plate used directly against the mine
roof shall be at least six (6) inches square, except that if the mine roof is
firm and not susceptible to sloughing, bearing plates five (5) inches square
may be used.
(5) A bearing plate used with wood or metal
materials shall be at least four (4) inches square.
(6) Wooden materials that are used between a
bearing plate and the mine roof in an area which will be used for three (3)
years or more shall be treated to minimize deterioration.
(7) When washers are used with roof bolts, the
washers shall conform to the shape of the roof bolt head and bearing plate.
(8) The diameter of a finishing bit shall be within
a tolerance of plus or minus 0.030 inch of the manufacturer's recommended hole
diameter for the anchor used.
(9) When separate finishing bits are used, they
shall be distinguishable from other bits.
Section 4. Tensioned Roof Bolts. (1) Roof bolts
that provide support by creating a beam of laminated strata shall be at least
thirty (30) inches long. Roof bolts that provide support by suspending the roof
from overlying stronger strata shall be long enough to anchor at least twelve (12)
inches into the stronger strata.
(2) Test holes, spaced at intervals specified in
the roof control plan, shall be drilled to a depth of at least twelve (12)
inches above the anchorage horizon of the bolts being used. When a test hole
indicates that bolts would not anchor in competent strata, corrective action
shall be immediately taken.
(3) The installed torque or tension ranges for roof
bolts as specified in the roof control plan shall maintain the integrity of the
support system and shall exceed neither the yield point of the roof bolt nor
anchorage capacity of the strata.
(4) In each roof bolting cycle, the actual torque
or tension of the first tensioned roof bolt installed with each drill head
shall be measured immediately after it is installed. Thereafter, for each drill
head used, at least one (1) roof bolt out of every four (4) installed shall be
measured for actual torque or tension. If the torque or tension of any of the
roof bolts measured is not within the range specified in the roof control plan,
corrective action shall be taken.
(5) In a working place from which coal is produced
during any portion of a twenty-four (24) hour period, the actual torque or
tension on at least one (1) out of every ten (10) previously installed,
mechanically anchored, tensioned roof bolts shall be measured from the outby
corner of the last open crosscut to the face in each advancing section.
Corrective action shall be taken if the majority of the bolts measured:
(a) Do not maintain at least the following percentages
of the minimum torque or tension specified in the roof control plan:
1. Seventy (70) percent; or
2. Fifty (50) percent if the roof bolt plates bear
against wood;
(b) Have exceeded the maximum specified torque or
tension by fifty (50) percent.
(6) The licensee or a person designated by him
shall certify by signature and date that measurements required by subsection
(5) of this section have been made. This certification shall be maintained for
at least one (1) year and shall be made available to an authorized representative
of the commissioner and representatives of the miners.
(7) A tensioned roof bolts installed in the roof
support pattern shall not be used to anchor trailing cables or used for any
other purpose that could affect the tension of the bolt. The hanging of
trailing cables, line brattice, telephone lines, or other similar devices which
do not place a sudden load on the bolts is permitted.
(8) An angle compensating device shall be used when
tensioned roof bolts are installed at an angle greater than five (5) degrees
from the perpendicular to the bearing plate.
(9) The first nontensioned grouted roof bolt
installed during each roof bolting cycle shall be tested during or immediately
after the first row of bolts has been installed. If the bolt tested does not
withstand at least 150 foot-pounds of torque without rotating in the hole,
corrective action shall be taken.
Section 5. Installation of Roof Support Using
Mining Machines with Integral Roof Bolters. When roof bolts are installed by a
continuous mining machine with integral roof bolting equipment:
(1) The distance between roof bolts shall not
exceed ten (10) feet crosswise;
(2) Roof bolts to be installed nine (9) feet or
more apart shall be installed with a wooden crossbar at least three (3) inches
thick and eight (8) inches wide, or material which provides equivalent support;
and
(3) Roof bolts to be installed more than eight (8)
feet but less than nine (9) feet apart shall be installed with a wooden plank
at least two (2) inches thick and eight (8) inches wide, or material which
provides equivalent support.
Section 6. Conventional Roof Support. (1) When
conventional roof support materials are used as the only means of support:
(a) The width of any opening shall not exceed
twenty (20) feet;
(b) The spacing of roadway roof support shall not
exceed five (5) feet;
(c) Supports shall be installed to within five (5)
feet of the uncut face;
(d) If supports nearest the face must be removed to
facilitate the operation of face equipment, equivalent temporary support shall
be installed prior to their removal;
(e) A straight roadway shall not exceed sixteen
(16) feet wide where full overhead support is used and fourteen (14) feet wide
where only posts are used;
(f) A curved roadway shall not exceed sixteen (16)
feet wide; and
(g) The roof at the entrance of all openings along
travelways which are no longer needed for storing supplies or for travel of
equipment shall be supported by extending the line of support across the
opening.
(2) Conventional roof support materials shall meet
the following specifications:
(a) The minimum diameter of cross-sectional area of
wooden posts shall be as follows:
Post Length
(in inches)
Diameter of
round post
(in inches)
Cross-sectional
area
of split post
(in square
inches)
60 or less
4
13
Over 60 to 84
5
20
Over 84 to 108
6
28
Over 108 to 132
7
39
Over 132 to 156
8
50
Over 156 to 180
9
64
Over 180 to 204
10
79
Over 204 to 228
11
95
Over 228
12
113
(b) Wooden materials used for support shall have
the following dimensions:
1. Cap blocks and footings shall have flat sides
and be at least two (2) inches thick, four (4) inches wide and twelve (12)
inches long;
2. Crossbars shall have a minimum cross-sectional
area of twenty-four (24) square inches and be at least three (3) inches thick;
3. Planks shall be at least six (6) inches wide and
one (1) inch thick.
(c) Cribbing materials shall have at least two (2)
parallel flat sides.
(3)(a) A cluster of two (2) or more posts that
provide equivalent strength may be used to meet the requirements of subsection
(2)(a) of this section.
(b) A post shall not have a diameter less than four
(4) inches or have a cross-sectional area less than thirteen (13) square
inches.
(4) Materials other than wood used for support
shall have support strength at least equivalent to wooden material meeting the
applicable provisions of this section.
(5) Posts and jacks shall be tightly installed on
solid footing.
(6) If a post is installed under roof susceptible
to sloughing, a cap block, plank, crossbar or materials that are equally
effective shall be placed between the post and the roof.
(7) Blocks used for lagging between the roof and
crossbars shall be spaced to distribute the load.
(8) A jack used for roof support shall be used with
at least thirty-six (36) square inches of roof-bearing surface.
Section 7. Pillar Recovery. (1) Full and partial
pillar recovery shall not be conducted on the same pillar line, except where
physical conditions such as unstable floor or roof, falls of roof, oil and gas
well barriers or surface subsidence require that pillars be left in place.
(2) Before mining is begun in a pillar split or
lift:
(a) At least two (2) rows of breaker posts or
equivalent support shall be installed as close to the initial intended
breakline as practicable and across each opening leading into an area where
full or partial pillar extraction has been completed; and
(b) A row of roadside-radius (turn) posts or
equivalent support shall be installed leading into the split or lift.
(3) Before mining is started on a final stump:
(a) At least two (2) rows of posts or equivalent
support shall be installed on not more than four (4) foot centers on each side
of the roadway;
(b)1. No more than one (1) roadway, which shall not
exceed sixteen (16) feet wide, shall lead from solid pillars to the final stump
of a pillar; and
2. If posts are used as the sole means of roof
support, the width of the roadway shall not exceed fourteen (14) feet.
(4) During open-end pillar extraction:
(a) At least two (2) rows of breaker posts or
equivalent support shall be installed on not more than four (4) foot centers.
(b) These supports shall be:
1. Installed between the lift to be started and the
area where pillars have been extracted; and
2. Maintained to within seven (7) feet of the face.
(c) The width of the roadway shall not exceed
sixteen (16) feet.
(d) If posts are used as the sole means of roof
support, the width of the roadway shall not exceed fourteen (14) feet.
Section 8. Installation and Use of Automated
Temporary Roof Support Systems. This section establishes the requirements for
and criteria of automated temporary roof support in an underground coal mine in
which both the coal bed thickness and the mining height exceed thirty (30)
inches.
(1) All roof bolting machines and continuous mining
machines with integral roof drills used in a working place in a coal mine shall
be provided with an approved automated temporary roof support system unless
other methods of temporarily supporting the roof have been approved by the
commissioner.
(2) Automated temporary roof support systems and
all other methods of temporarily supporting the roof shall be approved on an
individual mine basis by the commissioner and shall become part of the roof control
plan required by KRS 352.201(1).
(3)(a) The commissioner may grant a waiver of the
requirement for the use of an automated temporary roof support system if:
1. It has been demonstrated by the licensee and
determined during an investigation by an authorized representative of the
commissioner that:
a. The use of the system would create a greater
danger in areas where permanent supports have been installed than the method employed
or proposed for temporary support of the roof; or
b. The technology of an automated temporary roof
support system does not exist to allow compliance with the requirements of
subsection (5) of this section;
2. The configuration of the surface of the roof or
other conditions make the use of an ATRS system ineffective or impractical; or
3. The licensee's present roof control plan
provides adequate safety to the miner due to the geology or condition of the
roof.
(b) In granting a waiver, the commissioner may
approve the use of temporary jacks and posts in lieu of the ATRS.
(4)(a) In the event of a mechanical breakdown in
the ATRS, the licensee shall:
1. Provide for comparable temporary roof support;
2. Immediately notify the commissioner or his
authorized representative of:
a. The temporary roof support being used; and
b. The provisions being made to repair or replace
the ATRS.
(b) The commissioner or his authorized
representative shall order the removal of miners from the work area, if it is
determined that the roof support system being used during repair of the ATRS
does not adequately provide for their safety.
(5) A machine using, or used as, an automated
temporary roof support system shall comply with the following minimum
requirements unless a waiver has been granted or another method of temporarily
supporting the roof has been approved by the commissioner, pursuant to
subsection (2) of this section:
(a) The controls necessary to position the machine
and place the ATRS against the roof shall be operated from under permanently supported
roof, unless the design of the system provides adequate protection of the
miner;
(b) The ATRS shall be placed firmly against the
roof prior to work inby the permanent roof supports and shall remain in place
while work is performed, unless the configuration of the roof surface prevents
uniform placement of the ATRS;
(c) A hydraulic jack affecting the support capacity
of an ATRS shall have check valves or equivalent protection, to prevent support
failure if there is a sudden loss of hydraulic pressure;
(d) An ATRS used in conjunction with single bolt
installation shall elastically support, at a minimum, a deadweight load of
11,250 pounds for each five (5) feet by five (5) feet square area of the roof
to be supported;
(e) An ATRS consisting of pads or crossbars used in
single or multiple rows shall elastically support, at a minimum, a deadweight
load in pounds of 450 x ((L+5) x (W+5)), where L is the length of the support
structure from tip to tip and W is the width taken at the center line of a
support structure to the center line of another support structure;
(f) The actual capacity of the ATRS to support
elastically a deadweight load shall be certified by a registered professional
engineer;
(g) The distance that the ATRS may be set inby the
last row of permanent supports shall be dependent on the row spacing
requirements of the permanent roof supports and shall be authorized in the
approved roof control plan; and
(h) A person shall not work or travel inby the
ATRS.
Section 9. Manual Installation of Temporary
Support. (1) During manual installation of temporary support:
(a) Only a person engaged in installing the support
shall proceed beyond permanent roof support;
(b) The first temporary support shall not be set
more than five (5) feet from a permanent roof support and the rib.
(2) A temporary support shall be:
(a) Set so that the person installing the support
remains between it and two (2) other supports which shall not be more than five
(5) feet away;
(b) Completely installed prior to installation of
the next temporary support;
(c) Placed on no more than five (5) foot centers.
(3) After temporary supports have been installed,
work or travel beyond the permanent roof support shall be between:
(a) Temporary supports and the nearest permanent
support; or
(b) Other temporary supports.
Section 10. Warning Devices. Except during the
installation of roof supports, the end of permanent roof support shall:
(1) Be posted with a readily visible warning; or
(2) Have a physical barrier installed to impede
travel beyond permanent support.
Section 11. Roof Testing and Scaling. (1) A visual
examination of the roof, face and ribs shall be made immediately before any
work is started in an area and during the workshift as conditions warrant.
(2) If the mining height permits and the visual
examination does not disclose a hazardous condition, sound and vibration roof
tests, or other equivalent tests, shall be made where supports are to be
installed. If sound and vibration tests are made, they shall be conducted:
(a) After the automated temporary roof support
system is set against the roof and before other support is installed; or
(b) Prior to manually installing a roof support.
(3) Sound and vibration roof tests, or other
equivalent tests, shall begin under supported roof and shall not progress
further than the location where the next support is to be installed.
(4)(a) If a hazardous roof, face, or rib condition
is detected, the condition shall be corrected before work or travel is
conducted in the affected area.
(b) If the affected area is left unattended, each
entrance to the area shall:
1. Be posted with a readily visible warning; or
2. Have a physical barrier installed to impede
travel in the area.
(c) A bar for removing loose material shall be:
1. Available in the working place; or
2. On all face equipment, except haulage equipment;
and
3. Of a length and design that will permit the
removal of loose material from a position that will not expose the worker to
injury from falling material.
Section 12. Rehabilitation of Areas with
Unsupported Roof. (1) General rehabilitation plans shall be submitted with the
roof control plan.
(2) Before rehabilitating an area where a roof fall
has occurred or the roof has been removed by mining machines or blasting:
(a) The licensee shall establish the clean-up and
support procedures to be followed;
(b) A person assigned to perform rehabilitation
work shall be instructed in the clean-up and support procedures; and
(c) Ineffective, damaged or missing roof support at
the edge of the area to be rehabilitated shall be replaced or other equivalent
support installed.
(3) A person performing rehabilitation shall be
experienced in that work or supervised by a person, designated by the licensee,
who is experienced.
(4) If work is not being performed to rehabilitate
an area in active workings where a roof fall has occurred or the roof has been
removed by mining machines or by blasting, each entrance to the area shall be
supported by at least one (1) row of posts on not more than five (5) foot
centers, or equally effective support.
Section 13. Supplemental Support Materials,
Equipment and Tools. (1) A supply of supplemental roof support materials and
the tools and equipment necessary to install the materials shall be available
at a readily accessible location on each working section or within four (4)
crosscuts of each working section.
(2) The quantity of support materials, tools, and
equipment made available in accordance with this section shall be sufficient to
support the roof if adverse roof conditions are encountered, or in the event of
a roof fall.
Section 14. Longwall Mining Systems. For each
longwall mining section, the roof control plan shall specify:
(1) The methods that will be used to maintain a
safe travelway out of the section through the tailgate side of the longwall;
and
(2) The procedures that shall be followed if a
ground failure prevents travel out of the section through the tailgate side of
the longwall.
Section 15. Roof Control Plan. (1) When revisions
are proposed to the roof control plan required by KRS 352.201, only the revised
pages shall be submitted unless otherwise specified by the commissioner or his
authorized representative.
(2) The licensee shall be notified in writing of
the approval or denial of a proposed roof control plan or proposed revision.
(3) When approval of a proposed plan or revision is
denied, the deficiencies of the plan or revision and recommended changes shall
be specified and the licensee shall be afforded an opportunity to discuss the
deficiencies and changes with the commissioner or his authorized representative.
(4) Before new support materials, devices or
systems other than roof bolts and accessories are used as the only means of
roof support, the commissioner or his authorized representative may require
that the effectiveness of those new support materials, devices, or systems be
demonstrated by experimental installations.
(5) A proposed roof control plan or revision to a
roof control plan shall not be implemented before it is approved.
(6) Before implementing an approved revision to a
roof control plan, a person who is affected by the revision shall be instructed
in its provisions.
(7) The approved roof control plan and any revision
shall be available to the miners and representative of miners at the mine.
Section 16. Roof Control Plan Information. The
following information shall be included in each roof control plan:
(1) The name and address of the licensee;
(2) The name, address, mine identification number
and location of the mine;
(3) The name and title of the company official
responsible for the plan;
(4) A typical columnar section of the mine strata
which shall:
(a) Show the name and the thickness of the coalbed
to be mined and any persistent partings;
(b) Identify the type and show the thickness of
each stratum up to and including the main roof above the coalbed and for
distance of at least ten (10) feet below the coalbed; and
(c) Indicate the maximum cover over the area to be
mined.
(5) A description and drawings of the sequence of
installation and spacing of supports for each method of mining used;
(6) If an automated temporary roof support system
is used, the maximum distance that an automated temporary roof support system
is to be set beyond the last row of permanent support;
(7) If tunnel liners or arches are to be used for
roof support, specifications and installation procedures for the liners or
arches;
(8) Drawings indicating the planned width of
openings, size of pillars, method of pillar recovery, and the sequence of mining
pillars;
(9) A list of all support material required to be
used in the roof, face and rib control system, including, if roof bolts are to
be installed:
(a) The length, diameter, grade and type of
anchorage unit to be used;
(b) The drill hole size to be used; and
(c) The installed torque or tension range for
tensioned roof bolts.
(10) When mechanically anchored tensioned roof
bolts are used, the intervals at which test holes shall be drilled;
(11) A description of the method of protecting
persons:
(a) From falling material at drift openings; and
(b) When mining approaches within 150 feet of an
outcrop.
(12) A drawing submitted with a roof control plan
shall contain a legend explaining all symbols used and shall specify the scale
of the drawing, which shall not be less than five (5) feet to the inch or more
than twenty (20) feet to the inch;
(13) All roof control plan information, including
drawings, shall be submitted on eight and one half (8.5) by eleven (11) inch
paper, or paper folded to this size; and
(14) Any other information required by the
commissioner.
Section 17. Roof Control Plan Approval Criteria.
This section sets forth the criteria that shall be considered on a mine-by-mine
basis in the formulation and approval of roof control plans and revisions.
(1) Roof bolts shall be installed on centers not
exceeding five (5) feet lengthwise and crosswise, except as approved by the
commissioner or his authorized representative.
(2) When tensioned roof bolts are used as a means
of roof support, the torque or tension range shall be capable of supporting
roof bolt loads of at least fifty (50) percent of either the yield point of the
bolt or anchorage capacity of the strata, whichever is less.
(3) Any opening that is more than twenty (20) feet
wide shall be supported by a combination of roof bolts and conventional
supports.
(4) In any opening more than twenty (20) feet wide:
(a) Posts shall be installed to limit each roadway
to sixteen (16) feet wide, where straight, and eighteen (18) feet wide, where
curved; and
(b) A row of posts shall be set for each five (5)
feet of space between the roadway posts and the ribs.
(5) An opening shall not be more than thirty (30)
feet wide.
(6) If installing roof support using mining
machines with integral roof bolters:
(a) Before an intersection or pillar split is
started, roof bolts shall be installed on at least five (5) foot centers where
the work is performed;
(b) Where the roof is supported by only two (2)
roof bolts crosswise, openings shall not be more than sixteen (16) feet wide.
(7) Pillar recovery.
(a) During development, any dimension of a pillar
shall be at least twenty (20) feet;
(b) Pillar splits and lifts shall not be more than
twenty (20) feet wide;
(c) A breaker post shall be installed on a center
of not more than four (4) feet;
(d) Roadside-radius (turn) posts, or equivalent
support, shall be installed on not more than four (4) foot centers leading into
each pillar split or lift;
(e) Before full pillar recovery is started in areas
where roof bolts are used as the only means of roof support and openings are
more than sixteen (16) feet wide, at least one (1) row of posts shall be
installed to limit the roadway width to sixteen (16) feet. These posts shall
be:
1. Extended from the entrance to the split through
the intersection outby the pillar in which the split or lift is being made; and
2. Spaced on not more than five (5) foot centers.
(8) Openings that create an intersection shall be
permanently supported or at least one row of temporary supports shall be
installed on not more than five (5) foot centers across the opening before any
other work or travel is permitted in the intersection.
(9) In a working section where the mining height is
below thirty (30) inches, an automated temporary roof support system shall be
used to the extent practicable during the installation of roof bolts with roof
bolting machines and continuous-mining machines with integral roof bolters.
(10) In a mine with a longwall mining system:
(a) Systematic supplemental support shall be
installed throughout:
1. The tailgate entry of the first longwall panel
prior to any mining; and
2. In the proposed tailgate entry of each
subsequent panel in advance of the frontal abutment stresses of the panel being
mined.
(b) If a ground failure prevents travel out of the
section through the tailgate side of the longwall section, the roof control
plan shall address:
1. Notification of miners that the travelway is
blocked;
2. Reinstruction of miners regarding escapeways and
escape procedures in the event of an emergency;
3. Reinstruction of miners on the availability and
use of self-contained self-rescue devices;
4. Monitoring and evaluation of the air entering
the longwall section;
5. Location and effectiveness of the two (2) way
communication system; and
6. A means of transportation from the section to
the main line.
(c) The plan provisions addressed by paragraph (b)
of this subsection shall remain in effect until a travelway is reestablished on
the tailgate side of a longwall section.
(11) A roof control plan that does not conform to
the criteria set out in this section may be approved by the commissioner or his
authorized representative, if the plan provides effective control of the roof,
face, and ribs. The commissioner or his authorized representative may require
additional safety measures in a roof control plan.
Section 18. Evaluation and Revision of Roof Control
Plan. (1) A revision of the roof control plan shall be proposed by the
licensee:
(a) If conditions indicate that the plan is not
suitable for controlling the roof, face, ribs, or coal or rock bursts; or
(b) If accident and injury experience at the mine
indicates the plan is inadequate; the accident and injury experience at each
mine shall be reviewed at least every six (6) months.
(2) An unplanned roof fall, rib fall, and coal or
rock burst that occurs in the active workings shall be plotted on a mine map if
it:
(a) Is above the anchorage zone where roof bolts
are used;
(b) Impairs ventilation;
(c) Impedes passage of persons;
(d) Causes miners to be withdrawn from the area
affected; or
(e) Disrupts regular mining activities for more
than one (1) hour.
(3) The mine map on which roof falls are plotted
shall be available at the mine site for inspection by an authorized
representative of the commissioner and a representative of miners at the mine.
(4) The roof control plan for each mine shall be
reviewed every six (6) months by an authorized representative of the
commissioner. This review shall take into consideration any falls of the roof,
face and ribs and the adequacy of the support systems used at the time.
Section 19. Incorporation by Reference. (1)
"Standard Specification for Roof and Rock Bolts and Accessories",
(1995 Edition), American Society for Testing and Materials (ASTM), Designation
F 432-95.
(2) It may be inspected or copied at Kentucky
Department for Natural Resources, Administration Building, 1025 Capital Center
Drive, Suite 201, P.O. Box 2244, Frankfort, Kentucky 40602-2244, Monday through
Friday, 8 a.m. to 4:30 p.m.
(3) It may be obtained from the American Society
for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103,
(610) 832-9500. (23 Ky.R. 1478; Am. 2185; 2493; eff. 12-11-96; TAm eff.
8-9-2007.)
