(a) Where blasting of overburden or mineral is necessary, the blasting shall be done in accordance with established principles for preventing injury to persons and damage to residences, buildings and communities, and comply with the following:
(1) The weight in pounds of explosives to be detonated in any period less than an eight millisecond period without seismic monitoring shall conform to the following scaled distance formula: W = (D/50)(to the second power). Where W equals weight in pounds of explosives detonated at any one instant time, then D equals distance in feet from nearest point of blast to nearest residence, building or structure, other than operation facilities of the mine: Provided, That the scaled distance formulas need not be used if a seismograph measurement is located at the nearest protected structure is recorded and maintained for every blast. If access to the structure is refused by the owner of the protected structure, the measurement may be taken as close as practicable between the blast site and the protected structure. The peak particle velocity in inches per second in any one of the three mutually perpendicular directions shall not exceed the following values at any protected structure: