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Blasting Impacts Assessment for the Proposed GCC Rio Grande, Inc. Quarry in Pueblo County, Colorado <br />Human Response to Blasting <br />Since the duration of quarry blasts rarely exceed two seconds, the Wiss - Curves (see Figure 3.5) <br />indicate that ground vibration, at the nearest offsite dwelling (Blake Ranch) at expected levels <br />around 0.05 in/s will be barely detectable. Since blasting is limited by the Pueblo County Special <br />Use Permit No. 1999 -002 to the hours of 8:00 a.m. to 6:00 p.m., when ambient levels of <br />background noise and vibration are high — especially on an active cattle ranch— neighbors will <br />probably not know when blasts are occurring. <br />Impacts on Animals <br />While visiting the site, the author observed that cows and other farm animals were present on <br />Blake Ranch. Several years ago the author participated in a controlled study regarding the impacts <br />of blasting on a variety of animal species conducted by animal biologists at the Washington Park <br />Zoo in Portland, Oregon. In this study, researchers evaluated the effects of nearby (as close as 500 <br />ft) blasting noise and vibration on black rhinos, naked mole rats, elephants, spotted owls, snow <br />leopards, red pandas and several other species (Shepherdson et al, 1998). Elephants were <br />specifically chosen for this study because they are known to communicate at infrasonic noise <br />frequencies below human hearing range. The black rhinos were studied because zookeepers were <br />concerned that blasting might aggravate the problems with a pair that was unsuccessful at breeding <br />during the year prior to the construction work. The physiological effects of blasting were <br />evaluated by measuring the level of the stress hormone (cortisol) found in animal scat, before and <br />after blasting. In addition, for the first six blasts, the physical reactions of the tested animals were <br />observed when blasting occurred. <br />Maximum air overpressure for this blasting was about 130 dBL (Linear scale) and ground motion <br />reached about 0.25 in/sec. The researchers noted that the tested animals noticed the first blast or <br />two, however they quickly acclimated to the noise and vibration. Additionally, the black rhinos <br />mated successfully for the first time while construction was occurring on the tunnels. In their final <br />conclusions, the researchers found that the tested animals experienced no long -term negative <br />effects from the levels of noise and vibration produced by the construction blasting. <br />From the authors' personal experience, white - tailed deer were observed, on many occasions, <br />within several hundred feet of an open -air explosive testing range at the Reynolds Plant of the <br />former Atlas Powder Company in Tamaqua, Pennsylvania. The peak air overpressures, during <br />unconfined explosive tests, at that distance often exceeded 145 dBL. When blasts were detonated <br />the deer might casually lift their heads and look toward the test site. However, they never ran away <br />or appeared otherwise bothered by the loud noise. It was obvious that like the animals at the Metro <br />Washington Park Zoo in Portland, the deer had become acclimatized to the blasting noise. <br />For the past three years, the author has also been involved in an expansion project at the County of <br />Sonoma California Central Disposal Site in Petaluma, CA, where blasting has been regularly <br />occurred within 1,000 feet of dairy cows. Measurements in the cow pastures have indicated that <br />REVEY Associates, Inc. Page 15 July 2002 <br />