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were installed along the proposed gravel pit azea of quarry. Of these seven seismographs, two <br />triggered and recorded an event Beater than 0.03 inches per second or 119.6 dB(L). The <br />seismographs ranged from 1700 to 2000 feet from the test shot. The seismogaphs that were <br />triggered, recorded magnitudes of 0.06 inches per second and 106 dB(L) at 1,742 feet from the shot <br />and 0.03 inches per second and 106 dB(I.) at 2,006 feet from the shot. The third group of seven <br />seismographs were installed along a fence just north of the railroad tracks that run along the north bank <br />of the Arkansas River. These seismographs ranged from 2200 to 2900 feet from the test shot, and <br />none of the instruments registered an event of 0.03 inches per second or 119.6 dB(L) or greater. The <br />next goup utilized seven seismographs at the state park facilities along the south bank of the Arkansas <br />River and the north shoulder of FLghway 50. This group of seismographs ranged from 2500 to 3200 <br />feet from the test shot and did not register an event from the detonation of the test shot. The remaining <br />soc seismographs were phrced along Highway 50, County Road 3 and at the three neazest residences <br />(Wooten Residence - 3,100 feet; Clark Residence - 4,350 feet; and Clem Residence - 5,350 feet). Of <br />these six inshvrrrents, only the seismograph at the southwest corner of the Wooten Residence at 41941 <br />Highway 50 West recorded an event of 0.04 inches per second and 100 dB(I.). Included in the <br />appendix of this report is a table listing the seismograph locations and distances from the test shot, <br />THE SELSMOGRAPH <br />_• The SSU IvficroSeismographs are four-channel recorders which directly measure particle velocity in <br />three mutually perpendicular d'uectioru. The fourth channel is employed for monitoring air- <br />overpressure levels. The data stored on the seismograph's internal memory (when trigger levels are <br />exceeded) is later processed into analog printouts. Analog representations of the recorded data are <br />included in the appendix at the end of this report. <br />The fast ground vibration trace is labeled "transverse" and represents horizontal motion at right angles <br />to the blast. The second represents "vertical" particle velocity and is so labeled. The third is labeled <br />"longitudinal" and represents horizontal motion along a direct line between the recorder and the energy <br />source. <br />The SSU IvLcro-Seismographs have a ground vibration measuring range of 0.01 to 4.0 inches per <br />second with a frequency range of 2 to 250 hertz. The microphone which is utilized to measure airblast <br />has a maximum of 138 dB(L) and a frequency range of 2 to 200 hertz. The SSU NLcro-Seismographs <br />can store up to 20 waveform events and has the internal battery capacity to monitor for approximately <br />• 20 hours. Each of the seismographs have been calibrated during the past yeaz with exact calibration <br />information supplied for each recording. <br />,- <br />5 <br />r <br /> <br />