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Welborn Sullivan Meck&Tooley&Leadville Sanitation 13 <br /> June 9,2023 <br /> Figure 5: Estimated PPV at Sewer Line & WWTF Structure <br /> ;-- Typical Earth Vibrations <br /> due to Construction <br /> z (after Wiss, 1981) <br /> » 100 1 !'xr,, • - -<:ro Eateoded Dynamite <br /> E E - _ •• _ 1,2 Ton Ball.10 ItSwing <br /> —t Diesel Pik Driver.3b.000 fl4b <br /> ?0 • vibratory Pik DrtvM <br /> O X <br /> X —x—Pavement Breaker.611Drop <br /> > -4--2 Ton Drop Ban.40 R Dmp <br /> v + o-•--Caisson Drilling S Large Dozer <br /> v <br /> t: 1 --�--Trucks <br /> A <br /> t1 + X 0 is*tHrnrrnr <br /> Y <br /> ( _X—Crane Wkng <br /> G <br /> 0. 31 —+—Small Dozer <br /> + X — — Threshold of Perception <br /> - - • -Damage*treshold Res dental <br /> 0.01 of — -Damage Threshold CommerGai <br /> 10 100 0 <br /> Distance from Source, m <br /> The NHDOT report also states (with emphasis added): <br /> "Distance from Vibration Source - Distance from the source of energy <br /> is an important factor in the intensity of vibrations. Vibrations would <br /> theoretically be the same intensity at a given distance in all directions <br /> from the energy source, if the transmission medium is uniform and <br /> homogenous throughout. In reality, the conditions at a site are variable <br /> both laterally and vertically, encountering materials of different <br /> composition, density, water content, layering, etc. A general rule is that if <br /> the distance is reduced by half, the intensity of vibration should increase <br /> approximately by three times (Oriard, 2002). This relationship is very <br /> dependent on the conditions at the site. Vibration intensities at the <br /> ground surface are higher than those below ground. In general, the <br /> vibration intensity would decrease to approximately 50% of the <br /> surface value within 10 to 20 feet below the ground (Oriard, 2002). <br /> This is important when assessing the potential impact of vibrations <br /> on buried utilities. Buried utilities in good condition and properly <br /> installed are not only more confined and more resistant to vibration <br /> damage, but will likely experience less vibration intensity than that <br /> measured at the surface. <br /> This work concludes that: <br /> • Vibration intensity at either the sewer line or anywhere at the WWTF will be <br /> imperceptible. <br /> • Values are well below residential or commercial damage thresholds. <br /> • Vibrations experienced at the sewer will likely experience lower vibration intensity <br /> than estimated. <br /> 12. See response to No. 11. <br /> 13. See response to No. 11. <br /> Other <br /> From JVA memo. "Lastly, the Mill is proposing to use a lift station for the sanitary sewer. The lift <br /> station will be privately owned, operated and maintained by the Milll. (14) Lastly, another <br />