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MMRR quarry, M-2004-067 Response to Sept. 7 Adequacy Review September 12, 2005 Page 4 To the extent that the potential for dust generation is a function of the blast design, the Applicant submits that the planning undertaken by Lyman Henn, Inc. and reviewed as part of the second sequence of adequacy comments is based on standard practices that seek to fracture, not disintegrate, rock on the active quarry face. As noted by Allen Sorenson, "The main control that can be applied to the blast design is to ensure proper burden and stemming together with loading explosives to place energy release at the points where it will most efficiently break rock." Well-defined blasting science was used to generate the submitted blasting plan, and, among other basic considerations, the blast pattern seeks to minimize the amount of blasting powder necessary to dislodge rock, minimizing waste and optimizing the recovery of rock tonnage for specification aggregates. Should blasting at the site encounter unusual conditions, where typical burden to stemming ratios would not hold and excessive amounts of waste and dust could be generated, the operator will adjust the blast pattern accordingly or utilize other measures to ensure that blast energy is properly directed. Other measures could include blasting mats or thick dirt cover. It is anticipated that standard production blasting practices and the quarry layout and benching plan for the MMRR Quarry will be conducive to appropriate burden to stemming ratios in most to all blasting situations. The use of overburden or other measures to completely prevent flyrock is not warranted by general conditions at the proposed MMRR Quarry. For the record, due to a large buffer of permitted land around the affected area, the possibility that flyrock will be transported off-site or promote the transport of other particles offsite is extremely unlikely, if not physically impossible. Regulation by ATF and MSHA regarding both the use of explosives and worker safety during blasting events occupies the field of planning for on-site safety from flyrock hazards. In summary, the applicant is committed to practical measures to minimize dust generation at the MMRR Quarry. The applicant has committed to seek the appropriate permitting for air emissions, which includes control of sources. The applicant will additionally implement other standard dust control measures in the quarry operation. Extraordinary measures may also be warranted if, for example, concentrated radioactive sources are detected on the site; however, the presence of radioactivity on the site does not appear to be geologically significant and the Division does not identify any other basis to require extraordinary measures. Extremely restrictive blasting practices have not been required of similarly situated operations. We submit that the present blasting plan, coupled with the commitments and analysis incorporated herein, provides reasonable assurance that dust and other impacts associated with blasting will be controlled as is reasonably warranted.