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(Q), production (P) and access road (A) blastin,. A standard criteria for damage caused by <br />blasting is a particle velocity of 2 inches per second. This is exceeded in the production (P) <br />blasts at the control building and the solids building at the wastewater treatment facility and for <br />all of the blasts at the lighting facility. Another criteria for a tlueshold velocity is human <br />response. Quarry blasting typically results in frequencies of 10 to 100 cps and in this range the <br />threshold particle velocity for nuisance to humans is 0.2 inches per second. This threshold is <br />' exceeded in all of the blasts. The reason that the human threshold is useful is the affect that the <br />' blasting will have on the instrumentation in the wastewater treahnent facility. The human <br />threshold is faz exceeded at most of the structures which would indicate that the <br />' instrumentation may also be adversely affected. Typical seismic design of structures in this <br />' azea use apseudo-static analysis with an acceleration of 0.1 to 0 ~ G's. As can be seen from <br />the analyses, depending on the frequency, these accelerations are exceeded at all of the <br />structures. <br />The analyses are very sensitive to the transmissivity value (K). A value of 160 was <br />assumed in our analyses as well as Lyman and Henn's. This is an average value. A site specific <br />value should be determined. Once a site specific (K) value is determined, the analyses should <br />be redone. The analyses are also sensitive to the frequency. The actual frequency to be <br />expected should be determined. The results of the more accurate analyses should be provided <br />to the structural engineer so that the he can determine the possible affects on the structures. The <br />affects of the vibrations on the various instrumentation should also be determined. <br />At this time it is not possible to be certain that the quarry development and operation <br />will adversely affect the wastewater treatment facility and lighting facilities but it does appear <br />very likely. At a minimum it would appear that the instrumentation would be affected. Further <br />6 <br />