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velocity expected from each contributing watershed during the 100-yeaz,_ hour storm event. The applicant will need to verify that all pemrarrent spillways and drainage channels aze designed to withstand the peak velocity expected from such an event. For those applications where riprap installation will be necessary, the applicant will need to provide the details for riprap sizing such as the riprap D 50 and thickness of application. Please provide. 19. The March 15, 2004 Memo from Mike McDermid to Alex Schatz references the 10-yeaz, 24-hour storm event as the design storm event for temporary drainage stmctures. Please provide an assessment of the 10-yeaz, 24-hour storm; l0-yeaz, 6 hour storm; and 10-yeaz, 2-hour storm event for the watershed encompassing the proposed MMRR quarry and indicate which storm event produces the highest peak flow and conresponding peak flow velocity. The applicant will need to verify which of these storm events produces the highest peak flow and velocity, and then provide the corresponding peak flows and flow velocities for each contributing watershed used in the design of temporary spillways and/or drainage channels. The applicant will also need to verify that any new drainage culverts (24" or 48") to be installed aze designed to convey the peak flow expected from either a 10-year, _ hour or 100-yeaz, hour storm event, whichever is more appropriate. 20. The March 15, 2004 Memo from Mike McDermid to Alex Schatz references 4 attachments, ie: hydrology calculations, pit slope report, diversion channels design, road design pazameters. Please provide these 4 attachments. 21. Blasting Plan -The applicant has indicated that a blast vibration analysis and the on-going blast monitoring plan covering all affected azeas and structures will be submitted to the Division prior to commencement of blasting. It is the Division's position that the blast vibration analysis and blasting plan, per Rule 6.4.4(1), is an integral component of this application and must be provided with all of details outlined in Allen Sorenson's January 25, 2005 Memo (see attached copy). The blast vibration analysis and blasting plan must also include a detailed assessment of the possible surface and subsurface impacts, a monitoring plan that will be used to detect the presence or absence of offsite impacts, and proposed mifigation measures that will be implemented in the event a peak particle velocity of 0.75 ips is detected at any structure not owned or controlled by the quarry operation, or a peak particle velocity of 0.50 ips is detected at any older structure with plaster-on-lath walls that maybe within the zone of influence of quarry blast ground vibrations. Please provide. Uranium Mineralization 22. The applicant has proposed a Monitoring, Containment, and Control Plan to address the potential for adverse impacts to human health, and the environment from uranium mineralization resulting from quarrying activities and to ensure the operator's compliance with all applicable Federal, State, and local regulations. During the previous review period, the Division met with representatives from the Air Quality Control Division and Radiation Management Program of the Colorado Department of Health (CDII) to discuss the concerns expressed by I.L. Turner in reference to uranium mineralization from quarrying activities. As a result of our discussion, it has come to the Division's attention that it may be more appropriate for the Monitoring, Containment, and Control Plan to address the presence and impacts of radioactivity rather than uranium. The Division has asked for more input and assistance from the CDH specialists to assess appropriate monitoring requirements and protocol. We anticipate a response from the CDH specialists by July 29, 2005 and will forwazd their comments to the applicant as soon as they become available. 23. The applicant has proposed to "collect drill cuttings from at least one (1) representative sample point and promptly perform assay work for uranium content." The Division has asked the CDH to advise