Resolution 2017-31 - Laserfiche WebLink

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includes the trench area and any areas on either side of the trench that will be impacted in any way (including by vehicle traffic) by pipeline construction. 1.0 Topsoil Removal and Storage The Grantee shall comply with State of Colorado storm water management practices and shall bear the ultimate responsibility for providing adequate dust, erosion, and water quality controls throughout the duration of the project Topsoil should be removed by a front-end loader (preferred method) or grader. Under no circumstances should topsoil be removed under wet soil moisture conditions. The County's Primary Contact can provide assistance in determining topsoil depth and proper removal. The depth of the topsoil layer may vary. Topsoil may be delineated from the subsoil by a higher organic matter content (usually, but not always, indicated by a darker color) and a relatively loose and friable soil structure. The Primary Contact should be present at the site as topsoil removal is initiated to determine average topsoil depth. Typically, topsoil is between 4 and 8 inches in depth. Topsoil should be placed to one side of the disturbed area to protect it from vehicles and erosion. Any subsoil removed should be placed in an area that is separate from the topsoil and with soil horizons preserved in the order of original state. Under no circumstances shall subsoil be mixed with topsoil, and subsoil shall not be placed on top of the topsoil. The topsoil shall be protected from contamination by subsoil material, weeds, etc. and from compaction by construction equipment and vehicles. 2.0 Backfilling, Ripping/Relieving Compaction, and Grading The following activities must occur prior to redistribution of topsoil. Backfilling If the disturbance involves an excavation in excess of approximately 24" deep, the Grantee agrees to refill excavations with the removed native soil and with the soil horizons replaced in the order of original state. No new soils shall be imported to the site without County approval. The Grantee shall ensure that areas it disturbs do not subside significantly over time and that overall compaction of the top 24" of soil is not restrictive to root growth of plants. Following compaction of the backfill, the Primary Contact will determine if ripping/sub-soiling and chiseling is necessary to relieve soil compaction in the root zone to accommodate root growth and soil water holding capacity. Ripping/Relieving Compaction If deemed necessary, ripping/sub-soiling must be done to a minimum depth of 24 inches with no more than 20 inches between ripped intervals. Compacted areas must be chiseled to a minimum depth of 10 inches with no more than 10 inches between chiseled intervals. Two passes with a chisel may be necessary with the second pass at an angle to the first pass. Depending upon the size of soil clods left after ripping and/or chiseling, discing, culti-packing or other operations may be necessary to reduce the size of the clods. The Grantee shall consult with the Primary Contact to inspect the site at this time to make that determination. Callahan Open Space Access and Utility Easement 17