Chapter 22. Explosives
Regulation .01 General.LinkCopy Citation
A.
The permittee shall comply with all applicable local, State, and federal laws and regulations related to the storage, handling, preparation, and use of explosives.
B.
Blasting operations that use more than the equivalent of 5 pounds of explosives shall be conducted according to a time schedule approved by the Bureau.
C.
Not later than 1 year after the effective date of this chapter, all blasting operations shall be conducted by or under the direction of at least one person who has been certified by the Bureau in accordance with Regulation .08 of this chapter. Before this time all blast operations shall be conducted by or under the supervision of a person who has obtained a certificate of completion of training and qualification from the Bureau, or from any state with an equivalent blasting training program, provided the person passes an examination administered by the Bureau.
D.
Certificates of blaster certification shall be carried by blasters or shall be on file at the permit area during blasting operations.
E.
A certified blaster and at least one other person shall be present at the firing of a blast.
F.
Persons responsible for blasting operations at a blasting site shall be familiar with the blasting plan and site specific performance standards.
G.
A person who is not certified and is assigned to a blasting crew to assist in the use of explosives shall receive direction and training from the certified blaster in charge of blasting operations.
Regulation .02 Pre-blasting Survey.LinkCopy Citation
A.
A resident or owner of a dwelling or structure within 1/2 mile of the permit area may request a pre-blasting survey. This request shall be made, in writing, directly to the permittee or the Bureau, who shall promptly notify the permittee. The permittee shall promptly have a pre-blast survey of the dwelling or structure conducted and a written report of the survey prepared. If requested by the resident or owner, the permittee shall have any updated survey of any additions, modifications or renovations performed.
B.
The survey shall be conducted, by a person approved by the Bureau, to determine the condition of the dwelling or structure and to document any pre-blasting damage and other physical factors that could reasonably be affected by the blasting. Assessments of structures such as pipes, cables, transmission lines, and wells and other water systems shall be limited to surface condition and other readily available data. Special attention shall be given to the pre-blasting condition of wells and other water systems used for human, animal, or agricultural purposes and to the quantity and quality of the water.
C.
A written report of the survey shall be 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. Copies of the report shall be promptly provided to the person requesting the survey and to the Bureau. If the person requesting the survey disagrees with the results of the survey, he may notify, in writing, both the permittee and the Bureau of the specific areas of disagreement.
D.
A survey requested more than 10 days before the planned initiation of blasting shall be completed before the initiation of blasting.
Regulation .03 Public Notice of Blasting Schedule.LinkCopy Citation
A.
Each permittee shall publish a blasting schedule at least 30 days, but not more than 45 days, before beginning a blasting program in which blasts that use more than 5 pounds of explosive or blasting agent are detonated. The blasting schedule shall be published in a newspaper of general circulation in the locality of the blasting site. A copy of the certification of publication shall be retained with the blasting records in Regulation .07 of this chapter.
B.
At least 30 days before initiation of blasting, copies of the schedule shall be distributed to local governments, public utilities, and to each resident or owners of dwellings or other structures within 1/2 mile of the permit area described in the schedule. Copies sent to residents or owners of dwellings or other structures shall be accompanied by information advising the owner or resident how to request a pre-blasting survey. The copies shall be sent by mail or hand delivered. However, proof of notification shall be procured and retained with the blasting records in Regulation .07 of this chapter.
C.
The permittee shall republish and redistribute the schedule by mail at least every 12 months.
D.
Blasting Schedule Contents.
(1)
A blasting schedule may not be so general as to cover the entire permit area or all working hours, but shall identify as accurately as possible the location of the blasting sites and the time periods when blasting will occur.
(2)
The blasting schedule shall contain at a minimum:
(a)
Name, address, and telephone number of permittee;
(b)
Identification of the specific areas in which blasting will take place. Each specific blasting area described shall be reasonably compact and not larger than 300 acres.
(c)
Dates and time periods when explosives are to be detonated, expressed in not more than 4-hour increments. These periods may not exceed an aggregate of 8 hours in any one day.
(d)
Methods to be used to control access to the blasting area.
(e)
Types of audible warnings and all-clear signals to be used before and after blasting.
(f)
A description of unavoidable hazardous situations which have been approved by the Bureau for blasting at times other than those described in the schedule.
(g)
A notice that a resident or owner of a dwelling within 1/2 mile of the permit area may request a pre-blast survey by contacting the permittee or the Bureau in writing.
Regulation .04 Public Notice of Changes to Blasting Schedules.LinkCopy Citation
A.
Before blasting in areas or at times not in a previous schedule, the permittee shall publish and distribute a revised blasting schedule, at least 10 days but not more than 30 days before blasting. Information on requesting a pre-blast survey need not be repeated in a change notice.
B.
If there is a substantial pattern of non-adherence to the published blasting schedule as evidenced by the absence of blasting during a scheduled period, the Bureau may require that the permittee submit to the Bureau and republish a revised blasting schedule.
Regulation .05 Blasting Signs.LinkCopy Citation
All blasting signs shall be constructed, installed, and maintained in accordance with COMAR 26.20.18 on signs and markers.
Regulation .06 Surface Blasting Requirements.LinkCopy Citation
A.
All blasting shall be conducted between sunrise and sunset.
B.
Blasting shall be conducted at times approved by the Bureau and announced in the published blasting schedule. The Bureau may limit the area covered, specify more restrictive time periods, and limit the sequence of blasting as listed in the schedule, if the limitations are necessary or reasonable in order to protect the public health and safety or welfare.
C.
Unscheduled blasts may be conducted only when public or permittee health and safety so require and for emergency blasting actions. When an unscheduled blast is conducted, the permittee shall:
(1)
Using audible signals, notify residents within 1/2 mile of the blasting site;
(2)
Orally notify residents within 1,000 feet of the blasting site and the Bureau;
(3)
File a complete written report of the unscheduled blasting with the Bureau not later than 3 days after the unscheduled blast; the report shall include a detailed description of the reasons for the unscheduled blast, including reasons why the blast could not have been delayed until the next day, the actual time the blast was conducted, the warning notices that were given, and a copy of the blasting record.
D.
Warning and all-clear signals of different character that are audible within a range of 1/2 mile from the point of the blast shall be given. Each person within the permit area and each person who resides or regularly works within 1/2 mile of the permit area shall be notified of the meaning of the signals in the blasting schedule.
E.
Access to an area subject to flyrock from blasting shall be regulated 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 permittee has reasonably determined that:
(1)
No unusual circumstances, such as imminent slides or undetonated charges exist; and
(2)
Access to and travel in or through the area can be safely resumed.
F.
Blasting shall be conducted to prevent injury to persons, damage to public or private property outside the permit area, adverse impacts on underground mines and change in the course, channel, or availability of ground or surface waters outside the permit area.
G.
Except where lesser distances are approved by the Bureau based upon a pre-blasting survey, seismographic investigation, or other appropriate investigation, blasting may not be conducted within:
(1)
Three hundred feet of any building used as a dwelling, school, church, hospital, or nursing facility; and
(2)
Five hundred feet of facilities including, but not limited to, disposal wells, petroleum or gas-storage facilities, municipal water-storage facilities, fluid-transmission pipelines, gas or oil-collection lines, or water and sewage lines.
H.
Airblast.
(1)
Limits.
(a)
An airblast may not exceed the maximum limits listed below at the location of any dwelling, public building, school, church, or community or institutional building outside the permit area except as provided in §K of this regulation:
(b)
If necessary to prevent damage, the Bureau may specify lower maximum allowable airblast levels than those of §H(1)(a) of this regulation for use in the vicinity of a specific blasting operation.
(2)
Monitoring.
(a)
The operator shall conduct periodic monitoring to ensure compliance with the airblast standards. The Bureau may require airblast measurement of any or all blasts and may specify the location at which the measurements are taken.
(b)
The measuring systems shall have an upper end flat-frequency response of at least 200 Hz.
I.
Flyrock, including blasted material traveling along the ground, may not be cast more than half the distance from the blasting vicinity to the nearest dwelling or other occupied structure beyond the area of regulated access under §E of this regulation, or beyond the permit boundary.
J.
Ground Vibration.
(1)
In all blasting operations, except as otherwise authorized in §K of this regulation, the maximum ground vibration may not exceed the values approved in the blasting plan required under COMAR 26.20.02.13F. The maximum ground vibration for protected structures listed in §J(2)(a) of this regulation shall be established in accordance with either the maximum peak-particle-velocity limits of §J(2), the scaled-distance equation of §J(3), or by the Bureau of Mines under §J(4) of this regulation. All structures in the vicinity of the blasting area, not listed in §J(2)(a) of this regulation, 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, submitted by the operator of the blasting plan, and approved by the Bureau of Mines.
(2)
Maximum Peak Particle Velocity.
(a)
The maximum ground vibration may not exceed the following limits at the location of any dwelling, public building, school, church, or community or institutional building outside the permit:
(b)
A seismographic record shall be provided for each blast.
(3)
Scaled-Distance Equation.
(a)
An operator may use the scaled-distance equation, W = (D/Ds)B., to determine the allowable charge weight of explosives to be detonated in any 8-millisecond period, without seismic monitoring, where W = the maximum weight of explosives, in pounds, D = the distance, in feet, from the blasting site to the nearest protected structure, and Ds = the scaled-distance factor, which may initially be approved by the Bureau using the values for scaled-distance factor listed in the following chart:
(b)
For distances between 100 and 5,000 feet, solution of the equation results in the following maximum weight:
(c)
The development of a modified scale-distance factor may be authorized by the Bureau on receipt of a written request by the operator, supported by seismographic records of blasting at the minesite. The modified scale-distance factor shall be determined such that the particle velocity of the predicted ground vibration does not exceed the prescribed maximum allowable peak particle velocity of §J(2)(a) of this regulation, at a 95-percent confidence level.
(4)
Blasting-Level Chart.
(a)
An operator may use the ground vibration limits in Figure 1 to determine the maximum allowable ground vibration.
(b)
If the Figure 1 limits are used, a seismographic record including both particle velocity and vibration frequency levels shall be provided for each blast. The method for analysis of the predominant frequency contained in the blasting records shall be approved by the Bureau before application of this alternative blasting criterion.
(5)
The maximum allowable ground vibration shall be reduced by the Bureau to less than the limits otherwise provided by this regulation, if determined necessary to provide damage protection.
(6)
The Bureau may require an operator to conduct seismic monitoring of any or all blasts and may specify the location at which the measurements are taken and the degree of detail necessary in the measurements.
K.
Exemptions to Certain Standards. The maximum airblast and ground-vibration standards of §§H and J of this regulation may not apply at the following locations:
(1)
At structures owned by the permittee and not leased to another person;
(2)
At structures owned by the permittee and leased to another person, if a written waiver by the lessee is submitted to the regulatory authority before blasting.
L.
Blasting operations within 500 feet of active underground mines require approval of the Bureau and federal regulatory authorities concerned with the health and safety of underground miners.
Regulation .07 Records of Blasting Operations.LinkCopy Citation
A.
The operator shall retain a record of all blasts for at least 3 years. Upon request, copies of these records shall be made available to the Bureau and to the public for inspection.
B.
The records shall contain the following data:
(1)
Name of the operator conducting the blast;
(2)
Location, date, and time of blast;
(3)
Name, signature, and certification number of blaster conducting the blast;
(4)
Identification, direction, and distance, in feet, from the nearest blast hole to the nearest dwelling, public building, school, church, community or institutional building outside the permit area, except those described in Regulation .06K of this chapter;
(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 per hole;
(11)
The maximum weight of explosives detonated in any 8-millisecond period;
(12)
Initiation system;
(13)
Type and length of stemming;
(14)
Mats or other protections used;
(15)
Seismographic and airblast records, if required, which shall include:
(a)
Type of instrument, sensitivity, and calibration signal or certification of annual calibration,
(b)
Exact location of instrument and the date, time, and distance from the blast,
(c)
Name of the person and firm taking the reading,
(d)
Name of the person and firm analyzing the seismographic record, and
(e)
The vibration or airblast level recorded, or both;
(16)
Reasons and conditions for each unscheduled blast.
Regulation .08 Blaster Training Examination and Certification.LinkCopy Citation
A.
As used in this chapter, a blaster is a person who is directly responsible for the use of explosives in surface coal mining operations and is certified under this regulation.
B.
Qualifications. Persons applying to become certified blasters shall:
(1)
Be at least 21 years old;
(2)
Have received at least 1 year of qualifying experience under the direction and supervision of a certified blaster in the handling and use of explosives; and
(3)
Receive training including, but not limited to, the technical aspects of blasting operations and State and federal laws concerning the storage, transportation, and use of explosives.
C.
Training. Blaster training courses shall include training and discussion in the practical applications of:
(1)
Explosives, including:
(a)
Selection of the type of explosive to be used;
(b)
Determination of the properties of explosives which will produce desired results at an acceptable level of risk, and
(c)
Handling, transportation, and storage;
(2)
Blast designs, including:
(a)
Geologic and topographic considerations,
(b)
Design of a blast hole, with critical dimensions,
(c)
Pattern design, field layout, and timing of blast holes, and
(d)
Field applications;
(3)
Loading blast holes, including priming and boostering;
(4)
Initiation systems and blasting machines;
(5)
Blasting vibrations, airblast, and flyrock, including:
(a)
Monitoring techniques, and
(b)
Methods to control adverse effects;
(6)
Secondary blasting applications;
(7)
Current federal and State regulations applicable to the use of explosives;
(8)
Blast records;
(9)
Schedules;
(10)
Pre-blasting surveys, including:
(a)
Availability,
(b)
Coverage, and
(c)
Use of in-blast design;
(11)
Blastplan requirements;
(12)
Certification and training;
(13)
Signs, warning signals, and site control;
(14)
Unpredictable hazards, including:
(a)
Lightning,
(b)
Stray currents,
(c)
Radio waves, and
(d)
Misfires.
D.
The Bureau shall ensure that courses that cover the topics identified in §C of this regulation are available to train competent persons responsible for the use of explosives in surface coal mining operations.
E.
Examination.
(1)
The Bureau of Mines shall examine candidates for blaster certification who have successfully completed a training course approved by the Bureau and covering the topics set forth in §C of this regulation or have received training and certification as a blaster in any state with a federally approved blaster certification program.
(2)
The examination, at a minimum, shall include the topics set forth in §C of this regulation and shall review and verify the:
(a)
Competence of persons directly responsible for use of explosives in surface coal mining operations through a written examination in technical aspects of blasting and State and federal laws governing the storage, use, and transportation of explosives.
(b)
Practical field experience of the candidates as necessary to qualify a person to accept the responsibility for blasting operations in surface coal mining operations. The experience shall demonstrate that the candidate possesses practical knowledge of blasting techniques, understands the hazards involved in the use of explosives, and otherwise has exhibited a pattern of conduct consistent with the acceptance of responsibility for blasting operations.
F.
Certification. Upon determination that a candidate for blaster certification has successfully passed the examination and has been found to be competent and have the necessary experience, the Bureau shall issue to the individual a certificate indicating that the individual is a certified blaster for a period of 3 years.
G.
Suspension and Revocation.
(1)
The Bureau, when practicable, following written notice and opportunity for a hearing, may, and upon a finding of willful conduct, shall suspend or revoke the certification of a blaster during the term of certification or take other necessary action for any of the following reasons:
(a)
Noncompliance with any order of the Bureau;
(b)
Unlawful use in the work place of, or current addiction to, alcohol, narcotics, or other dangerous drugs;
(c)
Violation of any provision of the State or federal explosives laws or regulations;
(d)
Providing false information or a misrepresentation to obtain certification;
(e)
Refusal to exhibit his or her certificate to any authorized representative of the Bureau or the Office of Surface Mining, U.S. Department of the Interior, upon request.
(2)
If advance notice and opportunity for hearing cannot be provided, an opportunity for a hearing shall be provided as soon as practical following the suspension, revocation, or other adverse action.
(3)
Upon notice of a revocation, the blaster shall immediately surrender to the regulatory authority the revoked certificate.
H.
Recertification.
(1)
Recertification of all blasters is required every 3 years. Each applicant for recertification shall be currently certified and shall submit validated proof that he has had at least 1 year of blasting experience in the previous 3 years.
(2)
Reexamination. A certified blaster may not be recertified two consecutive times unless upon the second application, the applicant also successfully passes the examination as required in §E of this regulation.
I.
Protection of Certification. Certified blasters shall take every reasonable precaution to protect their certificates from loss, theft, or unauthorized duplication. Any occurrence of loss, theft, or unauthorized duplication shall be reported immediately to the Bureau.
J.
Conditions.
(1)
A blaster shall immediately exhibit his or her certificate to any authorized representative of the Bureau or the Office of Surface Mining, U.S. Department of Interior, upon request.
(2)
Blaster certifications may not be assigned or transferred.
(3)
A blaster may not delegate the blaster's responsibility to an individual who is not a certified blaster.
Chapter annotations
Authority: Environment Article, §15-503, Annotated Code of Maryland
History: Effective date:
History: Regulations .01—.08 were previously codified as COMAR 08.13.09.25A—H, respectively. Recodification occurred in April, 1993. For a history of these regulations before April, 1993, see "Administrative History of COMAR 08.13.09 before April, 1993" which follows COMAR 26.20.01.
History: Chapter recodified from COMAR 08.20.22 to COMAR 26.20.22, June 1996