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II: GROUND VIBRATION AND AIRBI.AST TEST PURPOSE The ground vibration and airblast test was conducted on October 21, 1997 at the proposed quarry site outside of Paricdale, Freemont County, Colorado. The purpose of the test was to evaluate the blast induced ground vibrations and a'v-home effects and compare the results to recommended criteria or applicable regulations governing the azea. PROCEDURE l:_ The data for this test was collected on October 21, 1997. The project consisted of monitoring a single hole signature blast that was 42 feet deep with 83.5 pounds of explosives in a 3.5 inch diameter hole. The signature blast was designed to be similar in energy to a representative hole in future production blasts. The vibration and au-home data was collected utiliarrg 30 Geosonics SSU iVlrao- Seismographs that were aligned in Sve artays along the south corridor of the proposed quarry. The array locations were picked to collect data at various locales that included structures, roadways, bridges, railroad tracks and geological formations that exist in relation to the proposed quarry site. The fiuthest seismographs from the signature blast did not record any data due to the ground vibration and air-home effects having attenuated to less than the pre-programmed trigger levels of 0.03 inches per second and 119.6 dB(L}; thus no seismic waveforms were obtained. These trigger levels are well below Office of Surface Mining (OSlvi) and U. S. Bureau of Mmes (CTSBIvi) recommended levels for ground vibration and air~oncussion. The distnbution of seismographs and the location of the signature blast is shown on a map in Appendix B at the end of this report. The thirty SSU IvLcro-Seismographs that were used in this test were setup to trigger at 0.03 inches per second and 119.6 dB(L). The seismographs were spiked and Emily coupled to the ground during installation. Once the seismographs were in place, a hand held computer was connected to wnfirrrr the correct setups and to place the seismograph into monitoring mode. In this mode, the seismograph would place into internal memory any occurrences where ground vibrations or air-overpressures reached or exceeded 0.03 inches per second and/or 119.6 dB(L). Once the test shot was detonated at 3:09 p.m. on October 21, 1997, the seismographs were once again connected to a hand held computer - and placed into the off mode. The seismographs were then placed in travel cases to be down-loaded. The recorded data is down-loaded from the seismographs by a computer, then it is printed and permanently stored on disk. ;,, The seismographs setup to monitor the test blast were aligned along the south corridor of the proposed ~- ~ quarry. The closest three seismographs to the blast were placed on the southern bank of the E' Tallahassee Watershed and ranged from 1200 to 1500 feet from the test shot. Of these three seismographs, only two registered an event greater than 0.03 inches per second and 119.6 dB(L). The recorded intensities were 0.07 inches per second and 106 dB(L) at 1,267 feet from the shot and 0.06 inches er second and 106 dB p (L) at 1,426 feet from the shot. The next group of seven seismographs a ~.