(a) Blasting shall be conducted between
sunrise and sunset, except that mine opening blasting conducted after the
second blast for that mine opening may be conducted at any time of day or night
as necessary to maintain stability of the mine opening to protect the health
and safety of mine workers. For mine opening blasting conducted after the
second blast, for that mine opening, the Department may approve ground
vibration and airblast limits at a dwelling, public building, school, church or
commercial or institutional structure, that are less stringent than those
specified in subsection (h) if consented to, in writing, by the structure owner
and lessee, if leased to another party.
(b) The Department may specify more
restrictive time periods, airblast or ground vibration limits, based on public
requests or other relevant information, according to the need to adequately
protect the public from the adverse affects of ground vibration, airblast or
safety hazards.
(c) Warning and
all-clear signals shall be different in pattern, audible within a range of 1/2
mile from the point of the blast, sounded before and after each blast. Each
person within the permit area shall be notified of the meaning of the signals
through appropriate instructions. These instructions shall be periodically
delivered or otherwise communicated in a manner which can be reasonably
expected to inform the persons of the meaning of the signals. Each person who
conducts blasting incident to surface mining activities shall:
(1) Give sufficient warning when a blast is
about to be fired, so that a person approaching within 500 feet of the blast
area may be warned of the danger and be given ample time to retreat a safe
distance from the blast area.
(2)
Erect signs at least 500 feet from the blast areas reading: "BLAST AREA-SHUT
OFF ALL TWO-WAY RADIOS" when electric blasting operations are located near
highways or other public ways. The letters of these signs shall be not less
than four inches in height on a contrasting background.
(3) Place at all entrances to the permit area
from public roads or highways conspicuous signs which state "WARNING!
EXPLOSIVES IN USE," which clearly explain the blast warning and all clear
signals that are in use and which explain the marking of blasting areas and
charged holes within the permit area.
(d) Access to an area possibly subject to
flyrock from blasting shall be controlled to protect the public and livestock.
Access to the area shall be controlled to prevent the presence of livestock or
unauthorized personnel during blasting and until an authorized representative
of the person who conducts the surface mining activities has reasonably
determined:
(1) That no unusual circumstances,
such as imminent slides or undetonated charges, exist.
(2) That access to and travel in or through
the area can be safety resumed.
(e) In all blasting operations, a scaled
distance of 50 or numerically greater may be used to determine the maximum
charge weight per delay interval of 8 milliseconds or greater without the use
of seismic instrumentation.
(f)
Blasting operations must meet the following requirements:
(1) Public highways and entrances to the
operation shall be barricaded and guarded by the operator if the highways and
entrances to the operations are located within 800 feet of a point where a
blast is about to be fired. The operator may use an alternative measure to this
requirement if the operator demonstrates, to the Department's satisfaction,
that the alternative measure is at least as effective at protecting persons and
property from the adverse affects of a blast. Alternative measures are measures
such as:
(i) Slowing or stopping traffic in
coordination with appropriate State or local authorities, including local
police.
(ii) Using mats to suppress
fly rock.
(iii) Designing the blast
to prevent damage or injury to persons and property located on the public
highways or at the operation's entrances by using design elements such as:
(A) Orienting the blast so that the direction
of relief is away from public highways or operation entrances.
(B) Adjusting blast design parameters
including:
(I) The diameter of
holes.
(II) The number of
rows.
(III) The number of
holes.
(IV) The amount and type of
explosive.
(V) The burden and
spacing.
(VI) The amount and type
of stemming.
(VII) The powder
factor.
(2) When a blast is about to be fired within
200 feet of a pipeline, the operator shall exercise necessary caution for the
protection of the pipeline. The operator shall notify the owner of the line of
his intention to blast, giving a description of the precautionary measures that
will be taken under §
211.62 (relating to blasting in
the vicinity of utility lines).
(3)
No blasting may be done within the confines of an area of 300 feet of a public
building or occupied dwelling unless prior written consent of the property
owner has been obtained.
(4)
Flyrock, including blasted material traveling along the ground, may not be cast
from the blasting vicinity more than 1/2 the distance to the nearest dwelling
or other occupied structure and in no case beyond the line of property owned or
leased by the permittee, or beyond the area of regulated access required under
subsection (d).
(5) Notwithstanding
other regulations, no blasting, whether of overburden or of coal, may be done
or performed in a manner and under such circumstances or conditions that eject
debris into the air, as to constitute a hazard or danger or do harm or damage
to persons or property in the area of the blasting.
(g) Blasting shall be conducted in a manner
to prevent injury to persons, damage to public or private property outside the
permit area, adverse impacts on any underground mine, or availability of
groundwaters or surface waters and shall be prohibited in all cases where the
effect of the blasting is liable to change the course or channel of any
strea
(h) In all blasting
operations, the blasts shall be designed and conducted in a manner that
achieves either a scaled distance of 90 or meets the maximum allowable peak
particle velocity as indicated by Figure 1 at the location of any dwelling,
public building, school, church or commercial or institutional building. Peak
particle velocities shall be recorded in three mutually perpendicular
directions-longitudinal, transverse and vertical. The maximum peak particle
velocity shall be the largest of any of three measurements. The Department may
reduce the maximum peak particle velocity allowed, if it determines that a
lower standard is required because of density of population or land use, age or
type of structure, geology or hydrology of the area, frequency of blasts or
other factors. The airblast level may not exceed 133 dBL.
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(i) The
maximum peak particle velocity and airblast limitations of this section do not
apply at the following locations:
(1) At
structures owned by the person conducting the mining activity, and not leased
to another party.
(2) At structures
owned by the person conducting the mining activity, and leased to another
party, if a written waiver by the lessee is submitted to the Department prior
to the blasting.
(j)
Where seismographs are not used to monitor peak velocity, the maximum weight of
explosives to be detonated within any 8 millisecond period may be determined by
formula W = (D/502) where W = the maximum weight of
explosives, in pounds, that can be detonated in any 8 millisecond period, or
greater and D = the distance, in feet, from the blast to the nearest dwelling,
school, church or commercial institutional building.
(k) Where a seismograph is used to monitor
the peak particle velocity a seismograph record shall be obtained for each
blast.
(l) The Department may
require a seismograph record of any blasts and may specify the location at
which the measurements are taken.