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The components required for a rigorous evaluation would be the maximum extemal pressure that may be applied to the pipe by the cover soil and vehicle traffic (including an impact factor of 2 for the moving load), the diameter and shell thickness of the pipe, the composition of the pipe, and a safety factor. Also, it is not clear if the five foot thick haul road embankment proposed for pipeline easement crossings will be applied to the existing ground surface or if topsoil will be stripped prior to installation of the road embankment. Since topsoil in this location is as much as 2 %x feet thick, its presence or absence in the haul road cross section would have a significant effect on the extemal load applied to the pipeline. Strain gauges can be used to monitor the pipeline and provide early warning of stress accumulation allowing for mitigation prior to pipeline rupture. An article on the use of strain gauges is attached For your reference. If [he applicant agrees to install the strain gauges and is able to gain the cooperation of the pipeline operator, then an installation plan (number and location of strain gauge emplacements), a monitoring and reporting plan, and a threshold criteria for mitigative action must be developed and submitted for Division review and approval. It is the Division's understanding that a single strain gauge emplacement is adequate to monitor approximately 200 lineaz feet of pipeline (Mike Bukovansky, personal communication). Threshold criteria for mitigation can be developed by considering that maximum allowable stresses in the pipeline should not exceed 50 percent of the pipeline steel specified minimum yield strength. If the pipeline operator refuses to cooperate in the installation and monitoring of strain gauges, then the applicant could put together a proposal to monitor the pipeline easement through the use of inclinometers, extensiometers, or similar devices. ' On Map #3, the operator located the topsoil stockpile over the area to be mined in 2007, 2008 and 2009. Rule 3.1.9(3) requires that topsoil stockpiles be stored in places and configurations where disturbance by ongoing mining operations will be minimized. Please inform the Division where the topsoil will be stored during the last years of mining, and include the locations on Map #3. 9. On page 6 of the permit application, the operator states that it is anticipated that between 6" and 12" of topsoil will be salvaged from the last 2-3 years of mining blocks, and that this amount of topsoil will be more than adequate to reclaim the site. The operator commits to a topsoil replacement depth between 12" and 18" over the entire site. Please inform the Division how the last 2-3 years of mining will enable enough topsoil to be salvaged to reclaim the entire site to a depth of 12" to l8". The operator needs to ensure that there is enough topsoil on site for reclamation at all times during mining for adequate reclamation or bond for importing topsoil. 10. The operator needs to provide additional detail regarding compliance with applicable Colorado water laws and regulations governing injury to existing water rights. The following items must be addressed to be in compliance with Rule 6.4.7; (a) The operator must locate on the map tributary water courses, wells, springs, stock water ponds, reservoirs and ditches on adjacent lands where such structures may be affected by the proposed mining operation. Please locate all of the above-mentioned features on