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Memo to Tyson Powell 2 September 2I, 2006 Blasting Vibration Control Plan File No. M-2004-067 The DRMS rejects the foregoing statements and the entire azgument that the Mined Land Reclamation Boazd (NLRB} erred in its determination that sufficient blasting controls are included in the permit application. The basis for the DRMS's position is as follows: The so-called commonly acceptable vibration levels maligned by the sanitation district do in fact assure that through compliance with permit conditions that blasting at the proposed quarry will cause no more than 0.75 inches per second peak particle velocity ground vibration at the sewage treatment plant. Vibration studies conducted over the last 44 years, and the literature produced, consistently demonstrate that vibrations of this amplitude are so small that they will not propagate pre-existing tiny plaster cracks in sheet rock walls. Given the results of these studies, any assertions that quarry blasting could damage concrete tanks at the sewage treatment plant aze patently absurd. It is likely that the sewage treatment plant uses monitoring instruments and other equipment with limited vibration tolerance. However, any designer and/or manufacturer of industrial equipment recognizes that vibration is pervasive and will produce equipment that will tolerate vibrations that will ordinarily occur in facilities where the equipment will be deployed. The DRMS produced a memo dated November 21, 2005 with literature citations demonstrating that vibration sources including door slamming, nail hammering, and walking across floors by heavy set persons can cause vibrations in excess of one inch per second peak particle velocity. That same memo references literature citations demonstrating that door slamming causes vibrations with amplitudes from 0.47 to 1.38 inches per second and foot stamping causes vibrations of 0.20 to 1.97 inches per second peak particle velocity. The memo is part of the MMRR permit application file, and thus is part of the record of the NLRB hearing on the quarry permit application. A copy of the DRMS November 21, 2005 memo is attached. If industrial requirements are such that vibration sensitive instruments and/or equipment must be deployed, there aze readily available and effective vibration damping mounting devices that will prevent vibration related damage. The DRMS testified to these facts during the NLRB hearing into the MMRR Quarry permit application, and the DRMS testimony in this regazd was then, and remains to this day un-refuted by the objectors to the quarry permit application. No qualified industrial engineer or industrial facilities designer would neglect the criticality of vibration tolerance in design of a sewage treatment plant such as the plant in question. If this plant is incapable of operation under vibration stresses as trivial as the 0.75 inches per second maximum peak particle velocity allowed under the approved MMRR Quarry permit application, then the plant is incapable of operation under normal operating conditions. When the Sanitation District initially asserted the claim that the instnunents and equipment in the sewage treatment plant were particularly vibration sensitive, the DRMS requested information about the plant's equipment and instnunentation vibration sensitivity. The Sanitation District, through their consultant, Leonard Rice Engineers provided vibration tolerance information for one, and only one, of the instruments in the sewage plant. That instrument is certified by the manufacturer to be tolerant of vibrations of up to 2.Og, or two times the acceleration of gravity. Tolerances in this range aze typical of highly sensitive instrumentation. The DRMS presented un- refuted testimony at the NLRB hearing into the subject permit application that 2.Og acceleration vibrations aze well in excess of the maximum 0.75 inches par second peak particle velocity