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_,1_ Soil Type Manburn Spicerton Unnamed Alluvium Tiagos Satanka Morset ,9 vc ra gc .St ripping Lrpth 1.25 feet 1.0 feet S.0 feet S.0 feet 2.5 feet 5.0 feet Only 0.5 acres of Satanka soil will be stripped, so this will not he discussed further. Based on chemical and physical analyses of these soils, only Spicerton and Ffanburn have limitations for stripping to a depth of five feet. The Spicerton soil is limited by a high SAR below a depth of 12 inches. The hlanhurn soil is a shallow soil with an average of approximately 20 inches to bedrock. Topsoil stripping has been completed at Pit I. A total of 49.9 acre-feet of topsoil has been stockpiled. Based on the soils resource information, 173.5 acre-feet of topsoil should be strippable from the Pit 2 area. These estimates show that there is sufficient topsoil available to cover the 123.9 acres of disturbance to a depth of 21 inches. Nowever, since it is difficult to maintain a uniform depth during redistri- bution, Wyoming Fuel Company estimates that between IF and 24 inches will be spread over the reclaimed lands. Overburden chemical analysis has isolated a condition which poses a significant hazard to successful reclamation. SAR, values in the overburden present a hazard to plant growth should either upward migration of sodium into the rhizosphere occur, or root development of deep-rooted plants, i.e., sagebrush, result in the downward extension of the rhizosphere into sodium-laden overburden. The spectre of total reclamation failure requires careful scrutiny of all aspects of overburden and topsoil handling. Three options for providing greater assurance that sodic problems will not develop in the reclaimed soils have been detailed by the Division. They arc: 1. Substantially more suitable soil material may exist beyond the depth (5') sampled at the site. The deep unnamed alluvium Tiagos and hforset soil types provide the possibility that substantially more soil material could be recovered. [dyoming Fuel Company could provide deeper sampling of soils, determine if greater salvage could reasonably be accomplished, and provide a depth of cover over sodic oc>erburden that represents the pre-mine conditions, or three feet. 2. From investigation of the overburden chemical analysis of hole LF12C-5, it appears that handling of overburden in such a wau that sodic materials will not be within three feet of the surface is possible. The analysis shown on pages 39-40, Volume I, Appendix C, of hole LM2C-5 shows that overburden is not a severe sodic hazard from five feet to 45 feet in the profile. Wyominy Fuel Company could drill a hole for over- burden chemical analysis in either Phase VIII or Phase IY. A comparison between the SAR values existing at various depths of hole Lh12C-S and the new hole could be made to determine if special handling of overburden would achieve the desired result of low sodium hazard material to a depth of three feet below the surface.