Current through Register Vol. 50, No. 9, March 1, 2024
RELATES TO:
KRS
350.151,
350.430
NECESSITY, FUNCTION, AND CONFORMITY: KRS Chapter 350 in
pertinent part requires the cabinet to promulgate rules and administrative
regulations establishing performance standards for protection of people and
property, land, water and other natural resources, and aesthetic values, during
underground mining activities and for restoration and reclamation of surface
areas affected by underground mining activities. This administrative regulation
sets forth specific requirements for the use of explosives for surface
blasting, including qualified supervision of blasting, preblasting surveys,
warning signals, restrictions on timing and location of blasting, limitations
on airblast and ground vibration, seismographic measurements, and records of
surface blasting operations.
Section 1.
General Requirements.
(1) This administrative
regulation applies only to surface blasting activities incident to underground
mining, including but not limited to, initial rounds of slopes and
shafts.
(2) Each permittee and each
person who conducts blasting operations shall comply with all applicable local,
state, and federal laws and regulations in the use of explosives.
(3) Each permittee shall have all surface
blasting operations conducted under the direction of a blaster certified in
accordance with
405 KAR
7:070. A certified blaster and at least one (1) other
person shall be present at the firing of a blast. Persons responsible for
blasting operations at a blasting site shall be familiar with the blasting plan
and site-specific performance standards.
(4)
(a) An
anticipated blast design shall be submitted if blasting operations will be
conducted within:
1. 1,000 feet of any
building used as a dwelling; public building; school; church; or commercial,
community, or institutional building outside the areas affected by surface
operations and facilities; or
2.
500 feet of an active or abandoned underground mine.
(b) The blast design shall be presented as
part of the permit application or shall be submitted to the department's
appropriate regional office at least thirty (30) days prior to initiation of
the blast.
(c) The blast design
shall contain sketches of the drill patterns, delay periods, and decking; shall
indicate the types and amounts of explosives to be used, critical dimensions,
and the locations of structures to be protected; shall include a general
description of structures to be protected; and shall contain a discussion of
design factors to be used, which protect the public and meet the applicable
airblast, flyrock, and ground vibration standards in this administrative
regulation.
(d) The blast design
shall be prepared and signed by a certified blaster.
(e) The cabinet may require changes to the
design submitted in order to ensure compliance with KRS Chapter 350; SMCRA; and
405 KAR Chapters 7 through 24.
Section 2. Preblasting Survey.
(1) At least thirty (30) days before
initiation of blasting, the permittee shall notify, in writing, all residents
or owners of dwellings or other structures located within one-half (1/2) mile
of the areas affected by surface operations and facilities how to request a
preblasting survey in accordance with subsection (2) of this section.
(2) A resident or owner of a dwelling or
other structure within one-half (1/2) mile of any part of the areas affected by
surface operations and facilities may request a preblasting survey. This
request shall be made in writing directly to the permittee or to the cabinet
which shall promptly notify the permittee. The permittee shall promptly conduct
a preblasting survey of the dwelling or structure. If a structure is renovated,
modified, or added to subsequent to a preblasting survey, then, upon request a
survey of such additions and renovations shall be performed in accordance with
this section.
(3) The survey shall
determine the condition of the dwelling or structure and document any
preblasting damage and other physical conditions that could reasonably be
affected by the blasting. Structures such as pipelines, cables, transmission
lines and cisterns, wells, and other water systems warrant special attention;
however, the assessment of these structures may be limited to surface condition
and readily available data unless additional data are specifically required by
the cabinet.
(4) A written report
of the survey shall be promptly prepared and signed by the person who conducted
the survey. The report may include recommendations of any special conditions or
proposed adjustments to the blasting procedure which should be incorporated
into the blasting plan to prevent damage. If the resident or structure owner or
his representative accompanies the surveyor, the report shall contain the name
of such person. Copies of the report shall be promptly provided to the person
requesting the survey and to the cabinet. If the person requesting the survey
disagrees with the results of the survey, he or she may submit, in writing to
both the permittee and the cabinet, a detailed description of the specific
areas of disagreement. The cabinet may require additional measures to ensure
that adequate and accurate information is included in the preblasting survey
and to ensure compliance with the requirements of this administrative
regulation.
(5) Any surveys
requested more than ten (10) days before the planned initiation of blasting
shall be completed by the permittee before the initiation of
blasting.
Section 3.
Surface Blasting Requirements.
(1) General
requirements.
(a) The permittee shall notify,
in writing, each residence within one-half (1/2) mile of the areas affected by
surface operations and facilities, the appropriate department regional office,
and local governments and public utilities of the proposed times and locations
of blasting operations and the characters, patterns, and meanings of the
warning and all-clear signals. Such notice shall be served no less than
twenty-four (24) hours and no more than thirty (30) days before blasting will
occur.
(b) All blasting shall be
conducted between sunrise and sunset. The cabinet may specify more restrictive
time periods based on public requests or other relevant information and
according to the need to adequately protect the public from adverse noise and
other impacts. Blasting may, however, be conducted between sunset and sunrise
if:
1. A blast that has been prepared during
the day must be delayed due to the occurrence of an unavoidable hazardous
condition and cannot be delayed until the next day because a potential safety
hazard could result that cannot be adequately mitigated;
2. Prior approval for conducting the blasting
between sunset and sunrise is obtained from the Kentucky Office of Mine Safety
and Licensing; and
3. A complete
written report of blasting at night is filed by the permittee with the cabinet
not later than three (3) days after the night blasting, not including
Saturdays, Sundays, or legal holidays. The report shall include a detailed
description of the reasons for the delay in blasting including why the blasting
could not be held over to the next day, identification of the time at which the
blast was actually conducted, a description of the warning notices given, and a
copy of the blast record required by Section 5 of this administrative
regulation.
(c)
Unscheduled blasts may be conducted only where public or operator health and
safety so require and for emergency blasting actions. When a permittee conducts
an unscheduled blast, the permittee, using audible signals, shall notify all
persons within one-half (1/2) mile of the blasting site and document the reason
for the unscheduled blast in accordance with Section 5(20) of this
administrative regulation.
(d) The
use of a charge weight of explosives in excess of 40,000 pounds in any blast
shall not occur without a valid permit for such blasting from the Kentucky
Office of Mine Safety and Licensing. Such a permit shall be present at the
blast site while such blasting is being conducted.
(2) Warnings. Warning and all-clear signals
of different character or pattern that are audible within a range of one-half
(1/2) mile from the point of the blast shall be given. Each person within the
areas affected by surface operations and facilities and each person who resides
or regularly works within one-half (1/2) mile of the areas affected by surface
operations and facilities shall be notified of the meanings of the signals as
identified in the blasting notification required in subsection (1) of this
section through appropriate communications. These notifications shall be
periodically delivered or otherwise communicated to such persons in a manner
which can reasonably be expected to inform such persons of the meanings of the
signals. Delivery or other appropriate communication of the meanings of such
signals to the head of a household or to the person in charge of a place of
business shall constitute sufficient notification of the meanings of such
signals to all persons at such household or place of business. Each permittee
shall maintain signs in accordance with
405 KAR 18:030,
Section 6.
(3) Access control.
Access to the blasting area shall be controlled to prevent the presence of
livestock or unauthorized personnel during blasting until the blaster has
reasonably determined:
(a) That no unusual
circumstances, such as imminent slides or undetonated charges, exist;
and
(b) That access to and travel
in or through the blasting area can be safely resumed.
(4)
(a)
Airblast. Airblast shall be controlled so that it does not exceed the values
specified in Appendix A of this administrative regulation at any dwelling;
public building; school; church; or commercial, community, or institutional
building outside the areas affected by surface operations and facilities except
as provided in subsection (8) of this section.
(b) In all cases except those involving the
use of C-weighted, slow-response devices, the measuring systems used shall have
a flat frequency response of at least 200 Hz at the upper end. The C-weighted
shall be measured with a Type 1 sound level meter that meets the standard
American National Standards Institute (ANSI) S1.4 1971
specifications.
(c) If necessary to
prevent damage, the cabinet shall specify lower maximum allowable airblast
levels than those in Appendix A of this administrative regulation for use in
the vicinity of a specific blasting operation.
(d)
1. To
evaluate compliance with the airblast standards of this administrative
regulation, throughout surface blasting operations the permittee shall
periodically monitor compliance with the airblast standards.
2. Monitoring pursuant to this paragraph
shall be deemed "periodic" if at least three (3) consecutive blasts are
monitored one (1) time during the period of January through June and one (1)
time during the period of July through December; provided however:
a. The cabinet may approve or require an
alternative frequency if deemed appropriate based on site conditions, the
anticipated blast design, the proposed blasting plan, and any other pertinent
information available to the cabinet. A plan for less frequent airblast
monitoring shall be deemed approved if the plan is specified as a condition of
permit issuance or is specified in the approved permit application and not
modified by a condition of permit issuance. A plan for more frequent airblast
monitoring shall be established in the approved permit application, as a
condition of permit issuance, or after permit issuance in accordance with
subparagraph 3 of this paragraph.
b. If detonation of explosives did not occur
during the designated monitoring period, airblast monitoring need not be
conducted during that period.
3. Subsequent to permit issuance, the cabinet
may require airblast measurements of any or all blasts and may specify the
locations of such measurements.
4.
The results of all airblast monitoring shall be recorded in accordance with
Section 5 of this administrative regulation.
(5) Flyrock. Flyrock, including blasted
material traveling along the ground, shall not be cast from the blasting site
more than half the distance to the nearest dwelling; public building; school;
church; commercial, community, or institutional building; or any occupied
structure and in no case beyond the boundary of the areas affected by surface
operations and facilities, or beyond the area of regulated access required
under subsection (3) of this section.
(6) Prevention of adverse impacts. Blasting
shall be conducted to prevent injury to persons; damage to public and private
properties outside the areas affected by surface operations and facilities;
adverse impacts on any underground mine; changes in the courses, channels, and
availability of surface waters outside the areas affected by surface operations
and facilities; and alterations of the ground water flow systems and ground
water availability outside the areas affected by surface operations and
facilities.
(7) Ground vibration.
(a) General. In all blasting operations
except as otherwise authorized by subsection (8) of this section, the maximum
ground vibration shall not exceed the values approved in the blasting plan
required under
405 KAR
8:040. The maximum ground vibration at the location of
any dwelling; public building; school; church; or commercial, community, or
institutional building outside the areas affected by surface operations and
facilities shall be established in accordance with either the maximum peak
particle velocity limits of paragraph (b) of this subsection, in accordance
with the scale-distance equations of paragraph (c) of this subsection, in
accordance with the blasting-level equations of paragraph (d) of this
subsection, or by the cabinet pursuant to paragraph (e) of this subsection. All
other structures in the vicinity of the blasting area, such as water towers,
pipelines, and other utilities; tunnels; dams; impoundments; and underground
mines shall be protected from damage by establishment of a maximum allowable
limit on the ground vibration proposed by the applicant in the blasting plan
and approved by the cabinet.
(b)
Maximum peak particle velocity. The maximum ground vibration shall not exceed
the limits established in Appendix B of this administrative regulation at the
location of any dwelling; public building; school; church; or commercial,
community, or institutional building outside the areas affected by surface
operations and facilities. Seismographic records shall be recorded for each
blast.
(c) Scale-distance
equations.
1. A permittee may use the
scale-distance equations of Appendix C of this administrative regulation to
determine the allowable charge weight of explosives to be detonated within any
eight (8) millisecond period without seismic monitoring.
2. The development of a modified
scale-distance factor may be authorized by the cabinet based on a written
request by the permittee supported by seismographic records of blasting at the
mine site. The modified scale distance factor shall be determined such that the
particle velocity of the predicted ground vibration will not exceed the limits
established in Appendix B of this administrative regulation at a ninety-five
(95) percent confidence level.
(d) Blasting-level equations. A permittee may
use the ground vibration limits calculated from the blasting-level equations in
Appendix D of this administrative regulation to determine the maximum allowable
ground vibration. If the blasting-level equations are used, a seismographic
record including both particle velocity and vibration-frequency levels shall be
provided for each blast. The method for the analysis of the predominate
frequency contained in the blasting records shall be approved by the cabinet
before application of this alternative blasting criterion.
(e) The maximum allowable ground vibration
shall be reduced by the cabinet beyond the limits of this subsection if the
cabinet determines that lower limits are necessary to provide damage protection
and ensure compliance with subsection (6) of this section.
(8) The maximum airblast and ground vibration
standards of this section shall not apply at the following locations:
(a) At structures owned by the permittee and
not leased to another party; and
(b) At structures owned by the permittee and
leased to another party, if a written waiver by the lessee is submitted to the
cabinet prior to blasting.
Section 4. Seismographic Measurements.
(1) The maximum peak particle velocity shall
be recorded as either the largest of the peak particle velocities measured in
three (3) mutually perpendicular directions or the vector sum
thereof.
(2) The cabinet may
require a permittee to conduct seismic monitoring of any or all blasts and may
specify the location at which such measurements are taken and the degree of
detail necessary in the measurement.
Section 5. Records of Blasting Operations. A
record of each blast, including any required seismograph reports, shall be
retained for at least five (5) years and shall be available for inspection by
the cabinet and the public on request. The record shall contain the following
data:
(1) Name of the permittee.
(2) Location, date, and time of the
blast.
(3) Name, signature,
certification number, and license number of the blaster in charge of the
blast.
(4) Identification of and
direction and distance, in feet, from the nearest blast hole to the nearest
dwelling; public building; school; church; or commercial, community, or
institutional building outside the permit area, except those described in
Section 4(8) of this administrative regulation.
(5) Weather conditions, including those which
may cause possible adverse blasting effects.
(6) Type of material blasted.
(7) Sketches of the blast pattern including
number of holes, burden, spacing, decks, and delay pattern.
(8) Diameter and depth of holes.
(9) Types of explosives used.
(10) Total weight of explosives
used.
(11) Total weight of
explosives used per hole.
(12)
Maximum weight of explosives detonated within any eight (8) millisecond
period.
(13) Maximum number of
holes detonated within any eight (8) millisecond period.
(14) Type of initiation system.
(15) Type of circuit.
(16) Type and length of stemming.
(17) Mats or other protection used.
(18) Type of delay detonator and delay
periods used.
(19) Seismographic
and airblast records, if used, which include for each record:
(a) Type of instrument, sensitivity, and
either calibration signal or certification of annual calibration;
(b) Exact location of instrument and the date
of, time of, and distance from the blast;
(c) For seismographic records, the actual
seismographic record.
(d) Name of
the person and firm taking the reading;
(e) Name of the person and firm analyzing the
seismographic record; and
(f) As
applicable, vibration and airblast levels recorded.
(20) Reasons and conditions for each
unscheduled blast.
Appendix A of 405 KAR 18:120 Airblast
Limitations
|
Lower frequency limit of measuring system in Hz
(+3dB)
|
Maximum level in dB
|
*0.1 Hz or lower - flat response
|
134 peak
|
2 Hz or lower - flat response
|
133 peak
|
6 Hz or lower - flat response
|
129 peak
|
*C-weighted, slow response
|
105 peak dBC
|
*These measuring systems shall be used only when approved by
the cabinet.
Appendix B of 405 KAR 18:120
|
Peak Particle Velocity Limits
|
Distance from the blasting site in feet
|
Maximum allowable
peak
particle velocity for
ground
vibration in inches
per second
|
0 to 300
|
1.25
|
301 to 5,000
|
1.00
|
5,001 and beyond
|
0.75
|
Appendix C of 405 KAR 18:120
|
Scale-distance Equations
|
Distance (D) from
the blasting site in feet
|
Scale-distance equation
|
0 to 300
|
W = (D/50)2
|
301 to 5,000
|
W = (D/55)2
|
5,001 and beyond
|
W = (D/65)2
|
where: W = the maximum weight of explosives that can be
detonated within any eight (8) millisecond period. where: D = the distance, in
feet, from the blasting site to the nearest protected structure.
Appendix D of 405 KAR 18:120
|
Blasting-level Equations
|
Blasting vibration frequency
|
Blasting-level equation
|
Hz < 4
|
V = 0.19 Hz0.9904
|
4 < Hz < 11
|
V = 0.75
|
11 < Hz < 30
|
V = 0.0719 Hz0.9776
|
Hz > 30
|
V = 2.00
|
where: Hz = the blast vibration frequency in hertz.
where: V = the maximum allowable particle velocity in inches
per second.
STATUTORY AUTHORITY: KRS Chapter 13A, 350.020, 350.028,
350.151, 350.465