[Ord. No. 98-34 §1, 2-25-1998; Ord. No. 04-016 §§1—4, 1-28-2004; Ord. No. 12-030 §1, 4-11-2012]
A.
All blasting operations within the County shall be conducted in strict accordance with the following rules and regulations and it shall be unlawful for any person to fail to observe and follow said rules and regulations when blasting. In the event there is a violation of said rules and regulations, the Director shall have the power and it shall be his duty to revoke the blasting permit issued in connection with the operation, revoke the license of the blaster in charge, all in accordance with the terms of this Chapter, and in addition, the violator or violators may be punished as otherwise provided by this Chapter for violations thereof.
1.
Blasting operations shall be carried on with the smallest possible number of persons present.
2.
Before firing any blast, all means of access to the danger zone (the extent of which shall be determined by the blaster, but in no case to be closer to the explosion than the blaster), shall be effectively guarded to exclude all unauthorized personnel. When practical, the blaster shall then sound a warning of sufficient intensity and duration to be distinctly audible to all persons within the danger zone and all such persons shall retire beyond the danger zone. The danger zone shall then be examined by the blaster to make certain that all persons have retired therefrom to a place of safety. No blast shall be fired while any person is in the danger zone.
3.
When the point of explosion is within three hundred (300) feet of a roadway, the blaster shall, just prior to the blast, designate a sufficient number of employees of the operator, each carrying a red warning flag, to stop all vehicular and pedestrian traffic on each possible route of travel within three hundred fifty (350) feet of the point of explosion until the blast has been fired.
4.
No person shall return to the danger zone until permitted to do so by the blaster as announced by audible or visual signal.
5.
Immediately following the blast the area shall be examined by the blaster for evidence of misfired charges.
6.
All misfires shall be reported at once to the superintendent or manager who shall then determine the safe and proper method of disposal. The unexploded charge shall be detonated if such can be accomplished without risk of injury to personnel or damage to property.
7.
When electric blasting caps are transported in a motor vehicle, equipped with a radio transmitter, they shall either be in their original package or stored in a closed metal box that is lined with a cushioning material such as wood or sponge rubber. When the electric caps are being placed into or removed from the box, the transmitter shall not be used.
8.
Unless otherwise expressly authorized in writing by the Director, all blasting operations shall be conducted at no less distance from any fixed or mobile radio transmitter than indicated in the following table:
| | Transmitter Power Output in Watts | Minimum Distance From Blasting Operations Using Electric Blasting Caps, in Feet |
|---|---|---|
| | 5—25 | 100 |
| 25—50 | 150 | |
| 50—100 | 220 | |
| 100—250 | 350 | |
| 250—500 | 450 | |
| 500—1,000 | 650 | |
| 1,000—2,500 | 1,000 | |
| 2,500—5,000 | 1,500 | |
| 5,000—10,000 | 2,200 | |
| 10,000—25,000 | 3,500 | |
| 25,000—50,000 | 5,000 | |
| 50,000—100,000 | 7,000 | |
| | When it can be demonstrated by means of approved tests that electric blasting may be carried out at lesser distances from the transmitter than required by the table shown, the Director may allow a variation from the requirements of said table. | |
| | When blasting operations are located near highways or other public ways, signs shall be erected at least five hundred (500) feet from the blast areas reading: "BLAST AREA - SHUT OFF ALL TWO-WAY RADIOS". The letters of these signs shall be not less than four (4) inches in height on a contrasting background. | |
9.
Under no circumstances shall the amount of explosives taken within three hundred (300) feet of a potential point of explosion exceed the amount estimated by the blaster as necessary for the blast. Such explosives shall be stacked in piles at least twenty-five (25) feet from the nearest holes being loaded and at such distances apart and that any premature explosion will not be likely to propagate from one (1) pile to another.
10.
The explosives containers, if any, shall be opened at the pile and carried up to the hole, one (1) case or unit at a time for immediate loading or placed at a loading station not less than six (6) feet from the hole except that not more than one hundred (100) pounds of explosives shall be allowed at the loading station at any one time. All empty explosives containers (boxes, bags, crates, etc.) shall be properly disposed of, daily, in a safe manner.
11.
Explosives shall be distributed in such a manner that the distances from storage piles to the allowable maximum quantity of one hundred (100) pounds of explosives at the loading station or between such one hundred (100) pound loading station piles shall not be less than the quantities shown in the following quantity-distance table:
| | Pounds of Explosives | Distance Between Piles of Explosives in Feet |
|---|---|---|
| | up to 50 | 21 |
| 100 | 25 | |
| 200 | 32 | |
| 300 | 37 | |
| 400 | 41 | |
| 500 | 44 | |
| 750 | 50 | |
| 1,000 | 55 | |
| 1,500 | 64 | |
| 2,000 | 70 | |
| 2,500 | 75 | |
| 5,000 | 96 | |
| 10,000 | 123 |
12.
Excessively large amounts of explosives shall not be delivered to the loading area at one (1) time. If deliveries of explosives are made by truck, the quantity permitted at or near the loading operations shall be limited to one (1) truck load. Other trucks loaded with explosives shall wait or be unloaded in separate safe places away from the loading operations.
13.
Explosives in excess of immediate requirements when removed from the main storage magazine and delivered in the vicinity of a blasting operation, shall be stored in a Class II magazine.
14.
Caps shall not be brought to the loading area nor attached to the detonating fuse until all is in readiness to fire the blast.
15.
Blast matting (which may include earth) shall be required when blast operations and/or geological conditions create fly rock that could damage or injure persons or property.
16.
In all blasting operations, except as hereinafter otherwise provided, the maximum peak particle velocity of any one (1) of three (3) mutually perpendicular components of the ground motion in the vertical and horizontal directions shall not exceed one (1) inch per second at the property line of the blast site. The Director may grant an exception to the rule when it is not an ongoing blasting operation.
17.
Seismographic instrumentation shall be required on any blast site where the nearest uncontrolled structure or public utility is located within a scaled distance of sixty-five (65). An uncontrolled structure is defined as any occupied building not owned or controlled by the explosives user. The seismograph shall be placed at or near the closest uncontrolled structure(s).
18.
Instrumentation shall be in good operating condition and be properly calibrated with a current (within one (1) year of date of use) calibration sticker affixed to each instrument. If an instrument(s) is found to be not operating properly or out of calibration, blasting operations shall be halted until the appropriate repairs or recalibration are performed or a proper instrument(s) is provided. Seismograph operator shall be trained in the use of that instrument(s).
19.
Blasting operations without instrumentation will be considered as being within the limits set forth in this Subsection if at a specified location on at least five (5) blasts instrumentation has shown that the maximum peak particle velocity at the specified location is fifty percent (50%) or less of the limit set forth in this Subsection, and with written permission from the Director, provided, that for all future blasts the scaled distance is equal to or greater than the scaled distance for the instrumental blast. However, if a scaled distance less than thirty-five (35) is employed, a seismograph is required regardless of the seismic readings of previous blasts. "Scaled distance" means the actual distance in feet divided by the square root of the maximum explosive weight in pounds that is detonated per delay period for delay intervals of eight (8) milliseconds or greater. If delay intervals less than eight (8) milliseconds are employed or if instantaneous blasting is employed, scaled distance shall be computed by dividing the actual distance in feet by the square root of the total explosive weight in pounds. Blasting operations which would result in ground vibrations that would have a particle velocity of any one (1) of three (3) mutually perpendicular components in excess of .30 inches per second and a frequency of less than 20 Hertz at any uncontrolled structure is prohibited. In addition, blasting is prohibited below the frequency of 3 Hertz. Blasting at frequencies of 20 Hertz to 30 Hertz shall not exceed a particle velocity of any one (1) of three (3) mutually perpendicular components of .50 inches per second. Blasting at frequencies above 30 Hertz shall not exceed a particle velocity of any one (1) of three (3) mutually perpendicular components of .80 inches per second. The Director may grant an exception to the requirements of this Subsection for blasting operations of less than thirty (30) days' duration, provided that such operations do not exceed the following limits at the nearest uncontrolled structure:
a.
The maximum peak particle velocity of any one (1) or three (3) mutually perpendicular components of the ground motion in the vertical and horizontal directions shall not exceed .50 inches per second for blasts below 10 Hertz or 1.0 inches per second for blasts from 10 to 30 Hertz or 1.5 inches per second for blasts above 30 Hertz.
b.
The maximum air blast shall not exceed one hundred twenty (120) decibels at 2 Hertz-flat response and above.
20.
Airblast limitations and measurements.
a.
Airblast shall be controlled so that it does not exceed the maximum limit specified below at any uncontrolled structure. Airblast monitoring equipment shall be used for all blasts at the nearest uncontrolled structure and records of that monitoring shall be retained for at least one (1) year for review by and production to the Director.
| Lower Frequency Limits of Measuring System, Hz (+ 3dB) | Maximum Level in dB |
|---|---|
| 2 Hertz or higher—flat response | 120 peak |
b.
All measuring systems used shall have a flat frequency response of at least two hundred (200) Hz at the upper end.
21.
When blasting in the vicinity of uncontrolled structures the explosives users will determine the structures lying within a scaled distance of thirty-five (35). The distance will be determined by the following:
| D = 35√W |
|---|
| Where D is the distance limit and W is the maximum charge weight per 8 ms delay interval. The explosives user shall contact the owners of structures within the distance limit and offer to have a pre-blast inspection performed on their structure at no cost to the owner. |
[Ord. No. 98-34 §1, 2-25-1998; Ord. No. 04-016 §5, 1-28-2004]
Unless otherwise set forth in this Chapter, blasting agents shall be transported, stored and used in the same manner as explosives. Storage of explosives shall comply with the Fire Prevention Code of St. Charles County, Section 500.400, Ordinances of St. Charles County, Missouri, as amended.
[Ord. No. 98-34 §1, 2-25-1998; Ord. No. 04-016 §6, 1-28-2004]
Buildings or other facilities used for mixing blasting agents shall be located, with respect to inhabited buildings, passenger railroads and public highways, in accordance with the Fire Prevention Code of St. Charles County, Section 500.400, Ordinances of St. Charles County, Missouri, as amended.
[Ord. No. 98-34 §1, 2-25-1998]
Persons using blasting agents shall comply with all of the applicable provisions of this Chapter for the use of explosives.
