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Blast Vibration Analysis.• Proposed MMRR Quarry Page 11 GEOTECHNICAL REPORT Hollingsworth Associates, Inc. conducted an independent geotechnical report to evaluate expected shock and vibration impacts to the BHCCSD Wastewater Treatment Plant and SDMD lighting facilities from the proposed MMRR Quarry; this report is included in toto as Appendix B. Using precise distances to individual receptors within the wastewater treatment plant and lighting fixtures along Highway 119, the report concluded "that the threshold velocity [0.75 ips] is exceeded in the blasting for the production (P) and the access road (A) for the wastewater treatment facility and the threshold velocity is exceeded for the lighting facilities for the quarry (Q), production (P) and access road (A) blasting." The geotechnical report is summarized by the following: 1. The blasting at the proposed MMRR Quarry is likely to cause some damage to the wastewater treatment facility and is likely to cause damage and disruption of the instrumentation. 2. The blasting at the proposed MMRR Quarry is likely to cause damage to the lighting facilities including damage to the foundation and the lights. 3. Further vibration studies should be conducted once site specific data is available. The results of these studies should be provided to the structural engineer as well as the instrumentation vendors to determine the effects. SUMMARY This report has examined receptors located in the zone of influence of blasting shock and vibration impacts emanating from the proposed MMRR Quarry. These receptors include the BHCCSD Wastewater Treatment Plant and SDMD highway lighting fixtures. A series of prescriptive standazds have been stipulated by the DMG to protect these (and other) offsite structures. Those standazds aze based on acceptable blast vibration criteria originating in a 1971 U.S. Bureau of Mines study Blasting Vibrations and Their Effect on Structures, Bulletin 65b. That study was intended to "establish[ment ofJ damage criteria for residential structures" (emphasis added). This report has demonstrated that the receptors closest to the blasting operations of the proposed MMRR Quarry -the BHCCSD Wastewater Treatment Plant and SDMD lighting fixtures -are not residential structures but represent far more sensitive receptors. The Hollingsworth Associates geotechnical report suggests that quarry operations will result in significant and possibly damaging shock and vibration. Thus, shock and vibration impacts from blasting operations have the potential to damage structures, treatment components (including disinfection), and critical instrumentation in the wastewater treatment plant, and adversely impact and shorten the operational life of specified lighting components. The safe blasting criteria established in Bulletin 656 and the 1977 Blasting Guidance Manual do not offer the degree of protection required to assure the continuous, safe, and uninterrupted operations of these vital public health and public safety facilities. ©Leonard Rice Engineers, Inc. November 10, 2005 -Jab No. 1086BCS03D