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Blast Vibration Ar7alysis. Proposed MMRR Quarry <br />Page 6 <br />Pipe structures -both steel and thermoplastic piping are employed at the wastewater treatment plant <br />for process (wastewater, sludge), support (water, treatment chemicals), and fire protection. <br />Depending on its diameter, piping connections may be flanged, threaded, or welded (soldered); each <br />will respond differently to vibration-induced stress with threaded connections likely the most <br />impacted. Vibration can result in fatigue failures of screwed pipe joints due to the high stress <br />intensification effects caused by the sharp notches at the base of the threads3. <br />The subject site is located in an area with only a low to moderate risk of seismic damage°. As such, <br />any additional blast-induced shock, vibration, and displacement of the pipes and related <br />appurtenances could require extensive retrofitting more in line with an area subject to greater seismic <br />risk to assure continued operational integrity of the system. The pipe could be subject to higher <br />loads, which in turn would require more robust support systems including special support devices <br />such as snubbers. Rigid attachment points to equipment (e.g., pumps or tanks) may react such that <br />additional stress could be induced in the pipes or equipment, leading to potential failures of the pipe, <br />tank, or joint. <br />' Appurtenances associated with the piping system are especially vulnerable to shock and vibration <br />with the manufacturers of one pressure regulating valve stating, "[P]iping systems must be designed <br />' and supported to prevent...vibration..." Product documentation for this device further notes that <br />such excessive vibration will void the product guarantee. <br />' Tanks -the wastewater treatment plant houses several tanks containing hazardous materials such as <br />50% sodium hydroxide and 93% sulfuric acid. In consonance with local building requirements, <br />' these tanks have not been seismically restrained on their foundations. When full, given the high <br />specific gravity of their contents, these tanks could weigh up to 6,500 pounds (425 gallons of 93% <br />sulfuric acid [specific gravity=1.84] contained in a 475-gallon tank). With this mass, lateral <br />' displacement due to blast-induced shock could lead to broken pipes or fittings, resulting in a <br />hazardous material spill, or severed electrical, instrumentation, and control conduits. Additional <br />retrofitted anchors or restraints would be required to prevent tanks from sliding or overturning. <br />' Rotating machinery -the plant contains numerous rotating machinery components, typically <br />electrically-driven motors attached to pumps or shafts. Air compressors aze also present. The pumps <br />' are used to move process water, fire protection water, wastewater, and sludge while the fans are used <br />as part of the plant's overall air handling system and odor control system. Compressed air is used as <br />part of the activated sludge treatment process. Proper alignment of the rotating shaft is critical to <br />continuous operation and extension of bearing life. Rotating shaft alignment is often conducted with <br />the use of lasers to assure precision and accuracy. <br />3 Piping Handbook, 6th Edition, Nayyaz, ML, McGraw-Hill, 1992 <br />°Colorado Division of Emergency Management, State Hazard Mitigation Plan, 1999, <br />httn:/hvww.dolastate.co.us/aerti/Mitication/plaidHazard Mit Plan.htm <br />e Hayward Industrial Products, Inc., One Hayward Industrial Drive, Clernmons, North Carolina 27012 <br />©Leonard Rice Engineers, Inc. November 10, 2005 -Job No. 1086BCS03D <br />