Requirements for the Use of Explosives

PURPOSE: This rule sets forth the requirements for the use of explosives pursuant to 444.855, RSMo. (1) General Requirements. (A) Each operator shall comply with all applicable state and federal laws and regulations in the use of explosives. (B) Blasts that use more than five (5 lbs.) pounds of explosive or blasting agent shall be conducted according to the schedule required by section (3) of this rule. (C) Blasters. 1. Prior to the approval by the federal office of surface mining of a blaster certification program designated to regulate and document the quality of persons responsible for the removal of coal overburden by means of explosives in Missouri, all these operations shall be conducted by experienced, trained and competent persons who understand the hazards involved. By July 1, 1989 all blasting operations in Missouri shall be conducted under the direction of a certified blaster. 2. A blaster and at least one (1) other person shall be present at the firing of a blast. 3. Any person responsible for conducting blasting operations at a blasting site shall— A. Be familiar with the blasting plan and site specific performance standards; B. Give direction and on-the-job training to persons who are not certified and who are assigned to the blasting crew or assist in the use of explosives. (D) Blast Design. 1. An anticipated blast design shall be submitted if blasting operations will be conducted within— A. One thousand feet (1000') of any building used as a dwelling, public building, school, church, community, institutional building or dam outside the permit area including those listed in paragraph (5)(D)1.; or B. Five hundred feet (500') of an active or abandoned underground mine. 2. The blast design may be presented either as part of a permit application or thirty (30) days before the initiation of blasting approved by the director or commission. 3. The blast design shall contain sketches of the drill patterns, delay periods and decking, and shall indicate the type and amount of explosives to be used, critical dimensions and the location and general description of structures to be protected, as well as a discussion of design factors to be used, which protect the public and meet the applicable airblast, flyrock and ground vibration standards in section (5) of this rule. 4. The blast design shall be prepared and signed by a certified blaster. 5. The director or commission may require changes to the design submitted. (2) Use of Explosives: Preblasting Survey. (A) At least forty (40) days before initiation of blasting, the operator shall ensure that all residents or owners of public buildings, schools, churches, community or institutional buildings, dwellings, dams or other structures, including those listed in paragraph (5)(D)1., located within one-half (1/2) mile of the permit area are notified by certified letter how to request a preblast survey. (B) A resident or owner of a dwelling or structure within one-half (1/2) mile of any part of the permit area may request a preblasting survey. This request shall be made, in writing, directly to the operator or to the director or commission who shall promptly notify the operator. The operator shall ensure that a prompt preblast survey of the dwelling or structure will be conducted and that a written report of the survey is promptly prepared. The operator shall ensure that an updated survey of any additions, modifications or renovations shall be performed if requested by the resident or owner. Surface Coal Mining and Related Activities (C) The operator shall ensure that the condition of the dwelling or structure be determined and that any preblasting damage and other physical factors that could reasonably be affected by the blasting be documented. 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 conditions and other readily available data. (D) The written report of the survey shall be signed by the person who conducted the survey. Copies of the report shall be promptly provided to the director or commission and to the person requesting the survey. If the person requesting the survey disagrees with the contents, recommendations, or both, contained in the report, s/he may submit to both the operator and the director or commission a detailed description of the specific areas of disagreement within forty-five (45) days of receipt of the survey. (E) The operator shall ensure that any surveys requested more than ten (10) days before the planned initiation of blasting shall be completed before the initiation of blasting. (F) The operator shall ensure that the director or commission is provided a list of all people outlined in subsection (2)(A), including their addresses. The list shall distinguish between persons who have agreed to a preblast survey and those who have refused a survey. (G) The operator shall ensure that the property owner be made aware that the preblast survey will be made at no cost to the property owner. (3) Use of Explosives: Blasting Schedule. (A) General Requirements. 1. The operator shall ensure that blasting operations are conducted at times approved by the director or commission and announced in the blasting schedule. The director or commission may limit the area covered, timing and sequence of blasting as listed in the schedule, if these limitations are necessary and reasonable in order to protect the public health and safety or welfare. 2. All blasting shall be conducted between sunrise and sunset, unless nighttime blasting is approved by the director or commission based upon a showing by the operator that the public will be protected from adverse noise and other impacts. The director or commission may specify more restrictive time periods for blasting. 3. Unscheduled blasts may be conducted only where public or operator health and safety so require and for emergency blasting actions. When an operator conducts an unscheduled blast, the operator, using audible signals, shall notify residents within one-half (1/2) mile of the blasting site and document the reason for the unscheduled blast in accordance with section (6) of this rule. (B) Blasting Schedule Publication and Distribution. 1. The operator shall publish the blasting schedule in a newspaper of general circulation in the locality of the blasting site at least ten (10), but not more than thirty (30), days before beginning a blasting program. 2. The operator shall distribute copies of the schedule to local governments and public utilities and to each local residence within one-half (1/2) mile of the proposed blasting site described in the schedule and to the director as soon as it has been published. 3. The operator shall republish and redistribute the schedule at least every twelve (12) months and revise and republish the schedule at least ten (10), but not more than thirty (30) days, before blasting whenever the area covered by the schedule changes or actual time periods for blasting significantly differ from the prior announcement. (C) Blasting Schedule Contents. The blasting schedule, at a minimum shall contain— 1. Name, address and telephone number of operator; 2. Identification of the specific areas in which blasting will take place; 3. Dates and time periods when explosives are to be detonated; 4. Methods to be used to control access to the blasting area; and 5. Type and patterns of audible warning and all clear signals to be used before and after blasting. (4) Use of Explosives: Blasting Signs, Warnings and Access Control. (A) Blasting Signs. Blasting signs shall meet the specifications of signs and markers outlined in 10 CSR 40-3.010(1). In addition, the operator shall— 1. Place conspicuous signs reading Blasting Area along the edge of any blasting area that comes within one hundred feet (100') of any public road right-of-way and at the point where any other road provides access to the blasting area; and 2. Place, at all entrances to the permit area from public roads or highways, conspicuous signs which state “Warning! Explosives in Use.” clearly listing and describing the meaning of the audible blast warning and allclear signals that are in use and which explaining the marking of blasting areas and loaded or charged holes awaiting firing within the permit area. (B) 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 permit area and each person who resides or regularly works within one-half (1/2) mile of the permit area shall be notified of the meaning of the signals in the blasting schedule. (C) Access Control. Access within the blasting area shall be controlled to prevent presence of livestock or unauthorized persons during blasting and until an authorized representative of the operator has reasonably determined that— 1. No unusual hazards, such as imminent slides or undetonated charges exist; and 2. Access to and travel within the blasting area can be safely resumed. (5) Use of Explosives: Control of Adverse Effects. (A) General Requirements. Blasting shall be conducted to prevent injury to persons, damage to public or private property outside the permit area, adverse impacts on any underground mine, and change in the course, channel or availability of surface or ground water outside the permit area. (B) Airblast. 1. Limits. A. Airblast shall not exceed the maximum limits listed as follows at the location of any dwelling, public building, school, church or community or institutional building outside the permit area, except as provided in subsection (5)(E) of this rule: Lower frequency limit of Maximum measuring system, Hz (=3dB) 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 *Only when approved by the commission or director B. If necessary to prevent damage, the director or commission shall specify lower maximum allowable airblast levels than those of subparagraph (5)(B)1.A. of this rule for use in the vicinity of a specific blasting operation. 2. Monitoring. A. The operator shall ensure that one (1) blast every twelve (12) months is monitored at the nearest uncontrolled structure to ensure compliance with the airblast standards. The record, as per section (6) of this rule, of this monitored event shall be submitted to the director no later than January 31 of each year for the year being monitored. The director or commission may require airblast measurement of any or blasts and may specify the locations at which the measurements are taken. B. The measuring systems shall have an upper end flat frequency response of at least two hundred hertz (200 Hz). (C) Flyrock. Flyrock traveling in the air or along the ground shall not be cast from the blasting site— 1. Either more than one-half (1/2) the distance to the nearest dwelling or other occupied structure or beyond the permit boundary, whichever is the lesser; or 2. Beyond the area of control required under subsection (4)(C). (D) Ground Vibration. 1. General. In all blasting operations, except as otherwise authorized in subsection (5)(E) of this rule, the maximum ground vibration shall not exceed the values approved in the blasting plan required under 10 CSR 40-6.050(4). The maximum ground vibration for protected structures listed in subparagraph (5)(D)2.A. of this rule shall be established in accordance with either the maximum peak particle velocity limits of paragraph (5)(D)2., the scaled distance equation of paragraph (5)(D)3., the blasting level chart of paragraph (5)(D)4. of this rule or by the commission or director under paragraph (5)(D)5. of this rule. All structures in the vicinity of the blasting area, not listed in subparagraph (5)(D)2.A. of this rule, such as water towers, pipelines, transmission lines 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 in the blasting plan and approved by the commission or director. 2. Maximum peak particle velocity. A. The maximum ground vibration shall not exceed the following limits at the location of any dwelling, public building, school, church, community or institutional building outside the permit area: Maximum allowable peak Scaled- particle distance velocity factor to be (Vmax) for applied ground without vibration, seismic Distance (D), from the in inches/ monitorblasting site, in feet second* -ing** (Ds) 0—300 1.25 50 301—5000 1.00 55 5001 and beyond 0.75 65 *Ground vibration shall be measured as the particle velocity. Particle velocity shall be recorded in three (3) mutually perpendicular directions. The maximum allowable peak particle velocity shall apply to each of the three (3) measurements. **Applicable to the scaled distance equation of subparagraph (5)(D)3.A. of this rule. 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)2, to determine the allowable charge weight of explosives to be detonated in any eight (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 commission using the values for scaled distance factor listed in subparagraph (5)(D)2.A. of this rule. B. The development of a modified scaled distance factor may be authorized by the director or commission on receipt of a written request by the operator, 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 prescribed maximum allowable peak particle velocity of subparagraph (5)(D)2.A. of this rule at a ninety-five percent (95%) 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 the analysis of the predominant frequency contained in the blasting records shall be approved by the director or commission before application of this alternative blasting criterion. Surface Coal Mining and Related Activities 5. The maximum allowable ground vibration shall be reduced by the director or commission beyond the limits otherwise provided by this section, if determined necessary to provide damage protection. 6. The director or commission may require an operator to conduct seismic monitoring of any blasts or may specify the location at which the measurements are taken and the degree of detail necessary in the measurement. (E) The maximum air blast and ground vibration standards of subsections (5)(B) and (D) of this rule shall not apply at the following locations: 1. At structures owned by the permittee and not leased to another person; and 2. At structures owned by the permittee and leased to another person, if a written waiver by the lessee is submitted to the director before blasting. (6) Use of Explosives: Records of Blasting Operations. The operator shall retain a record of all blasts for at least three (3) years. Upon request, copies of these records shall be made available to the director or commission and to the public for inspection. These records shall contain the following data: (A) Name of the operator conducting the blast; (B) Location, date and time of the blast; (C) Name, certification number and signature of the blaster in charge conducting the blast; (D) 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 or those outlined in paragraph (5)(D)1., except those described in subsection (5)(E); (E) Weather conditions, including those which may cause possible adverse blasting effects; (F) Type of material blasted; (G) Sketches of the blast pattern including number of holes, burden, spacing, decks and delay pattern; (H) Diameter and depth of holes; (I) Type of explosives used; (J) Total weight of explosives used per hole; (K) The maximum weight of explosives detonated in an eight (8)-millisecond period; (L) Initiation system; (M) Type and length of stemming; (N) Mats or other protections used; (O) Seismographic and airblast records, if required, which shall include: 1. Type of instrument, sensitivity and calibration signal or certification of annual calibration; 2. Exact location of instrument and the date, time and distance from the blast; 3. Name of the person and firm taking the reading; 4. Name of the person and firm analyzing the seismographic record; and 5. The vibration, air blast level, or both, recorded; and (P) Reasons and conditions for each unscheduled blast. AUTHORITY: sections 444.530 and 444.810, RSMo Supp. 1999.* Original rule filed Oct. 12, 1979, effective Feb. 11, 1980. Amended: Filed April 14, 1980, effective Aug. 11, 1980. Amended: Filed July 15, 1980, effective Nov. 13, 1980. Amended: Filed Aug. 8, 1980, effective Dec. 11, 1980. Amended: Filed Dec. 10, 1980, effective April 11, 1981. Rescinded and readopted: Filed Jan. 5, 1987, effective July 1, 1987. Amended: Filed July 1, 1987, effective Sept. 25, 1987. Amended: Filed June 2, 1988, effective Aug. 25, 1988. Amended: Filed July 3, 1990, effective Nov. 30, 1990. Amended: Filed March 21, 2000, effective Oct. 30, 2000. *Original authority: 444.530, RSMo 1979, amended 1983, 1990, 1993, 1995; and 444.810, RSMo 1979, amended 1983, 1993, 1995.