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ii. Exact location of instrument, the blast date and time, and the instrument distance <br />from the blast <br />iii. Name of the person and firm taking the reading <br />iv. Name of the person and firm analyzing the seismographic record <br />v. The vibration level recorded <br /> <br /> <br />7. Blasting best practices <br /> <br />After detonation, shock waves and gas pressure cause dynamic stresses around a blast hole with seismic <br />waves propagating away from it, and produces elastic deformation in the rock mass. Some adverse <br />effects from blast are ground vibration, air pressure (airblast), dust, fumes, and flyrocks. <br />Geological conditions, quantity of explosives detonated at any given time, charge confinement, blasting <br />design, and delay intervals will influence blasting vibrations, and ground movement. Portland Plant had <br />implemented a ground vibration monitoring system at Bear Creek Quarry (BCQ), with several near field <br />(200-250ft) and far field (father than 350ft) seismographs, it allows Quarry personal to assess <br />compliance with regulations, prevent damage to structures, quarry walls, final walls stability, and <br />identify any critical information to protect nearby structures, also minimize liability claims. <br />BCQ criteria to analyze ground motion are peak particle velocity (PPV – inches/sec) and dominant <br />frequency (Hz), they are widely accepted measurements for potentially damaging to structures and <br />control walls stability in the quarries. Red Creek Quarry (RCQ) will follow, and will improve best practices <br />from BCQ. Monitoring will be a key piece to define and adjust drilling, blasting, blast design parameters <br />with rock mass properties on it. <br />At Red Creek Quarry (RCQ) Smokey Hill Member, Fort Hays Member, and Codell sandstone can be <br />considered as hard and blocky rock mass; most of materials can be classified as rock Type 3 “fair” rock <br />strength (25Mpa- 50Mpa). Design configuration allows 36ft bench high, 20ft berm width, 75° slope <br />angle, and 52° overall slope at final 150ft high wall. “SRK, Red Creek Geotechnical Assessment Report”. <br />There are several controlled blasting techniques to improve the stability of the final slope face, and <br />minimize damage. It is possible combine them as geologic conditions, mass rock properties, and drilling- <br />blasting settings allows desired results. Next list: <br />- Line drilling <br />- Trim blasting <br />- Buffer blasting <br />- Smooth wall blasting <br />- Air decking <br />- Presplitting <br />RCQ will evaluate Trim blast and Modified production blast (combination of more favorable techniques <br />at RCQ). Both methods goal is to reduce damage to Red Creek canyon and final quarry walls. Developing <br />RCQ will require drilling, blasting, loading, and hauling of almost 3Mio t of limestone and waste to <br />temporary stockpiles. It will open up an area to establish Quarry offices, shop, secondary crusher and <br />starting point for convey system. Thus, monitoring system will collect and assess any concern related to