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4)40 <br /> B cr[] <br /> The depth of soil also appeared to be directly correlated to the vegetation. In the areas with the least <br /> amount of soil kochia and russian thistle were the predominate species while in areas with deeper soils <br /> more grasses were evident. <br /> Reclamation <br /> Reclamation of the mined area on the O'Brien property has not returned the land to a productive <br /> agricultural state.As mentioned above, a majority of the vegetative cover across the mined area is <br /> comprised of kochia and russian thistle.These weeds are listed as troublesome weeds by Larimer County <br /> and are not agronomically beneficial and should not be considered final vegetative cover by the DRMS. <br /> Finally, kochia and russian thistle are not prevalent outside of the mined area on the O'Brien property. <br /> The lack of permanent vegetative grass cover is likely due to the lack of topsoil found within the mined <br /> areas of the O'Brien property.To successfully reclaim the mined areas of the O'Brien property topsoil of <br /> pre-mined quality and quantity will need to be imported.The imported topsoil should meet soil texture <br /> of the non-mined area with sufficient microbial and organic matter concentrations to sustain a <br /> permanent grass crop there can be used for agriculture similar to the non-mined vegetative conditions. <br /> The estimated 2 inches of topsoil and 2 inches of Big Thompson River depositional sediment does not <br /> meet these criteria. Based on my 20 years of reclamation experience,without proper reclamation <br /> procedures there is no immediate process to get a self-sustaining permanent grass crop to succeed <br /> without the application of high quality topsoil. <br /> Stabilization <br /> Review of the ponds and associated land bridge it appears that stabilization has not been achieved <br /> throughout most of the mined areas.There is evidence of sluffing in these areas.The sluffing will <br /> ultimately lead to deterioration of the land bridge and pond banks.The upkeep of these unstable banks <br /> will lead to long-term operations and maintenance costs to the landowners. In my opinion all the banks <br /> should be brought back to a stable angle and vegetated with self-sustaining vegetation. <br /> Conclusion <br /> In my opinion the soil,vegetation and stabilization of the O'Brien mined areas do not meet criteria for <br /> maintaining self-sustaining permanent vegetation and are would not be considered stable. It is my <br /> opinion that additional topsoil of proper quality and quantity will need to be imported to create an <br /> environment where successful reclamation can be achieved. To reclaim the site a full reclamation plan, <br /> prepared by a soil scientist, agronomist, or range management professional experienced in disturbed <br /> land reclamation,should be developed that includes information regarding soil depths,seed mix <br /> selection,seed bed preparations (compaction relief,tillage, amendments,fertilizer application, etc), <br /> seeding methods, seeding timing. In areas where unstable surfaces exist, pond banks and land bridge, <br />