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t will "blend into and complement the drainage pattern of the surrounding terrain" (definition of ADC, federal interim regs). The proposal to line drainage channels with wooden laths would at best be a temporary measure, and would not prevent the formation of channels on other portions of the property. 2. On page 11, the applicant states that the proposed contours would result in the formation of a "wet meadow" immediately south of Mann Draw. The staff feels that this would be unlikely. The soils in the vicinity of Mann Draw are currently highly saline and sodic, with a clay texture. As currently planned, this will also be the case after mining. A' sodic clay tends to swel l when _ +o n ~~ ~f/^f,b~. ,4.,y wet, sealing the surface wi puddle and-eventually ~ Ww~tr on f/te Scv- cc evaporate. Salts in the soil and the water will accum- ulate in this low area, resulting in the eventual forma- tion of a salt pan, not a "wet meadow." 3) Several references are made in the application to a shallow water table which currently exists in low areas south of Mann Draw, and which the applicant feels mould be re-established following reclamation. Again, this is unlikely. Underlying the low areas would be backfill materials, which tend to be highly permeable. Any water entering this material would tend to percolate down t a considerable depth. In order to create a perched shallow water table, an impermeable layer would be necessary. No such layer will exist in the backfill. b) The statement is made on page 10 that the final sediment pond will be removed when "revegetation has been well enough established so that a summer thunderstorm will not cause severe silting of Mann Draw." The applicant should realize that the removal of this pond will be controlled by regulations, and must be approved by this office. c) The staff cannot recommend approval of the proposed depths of top- soil salvage or replacement at this time. The reasons for this are described in detail in the comments to the soils section. d) The staff would recommend deeply ripping the overburden prior to re-application of topsoil (to about 36 inches). There are clear indications that relieving the compaction of the overburden in this way will greatly enhance .revegetation success. e) Since the topsoil stockpiles will remain In place as long as 8 or 9 years, the use of a temporary cover crop of annual grains to stabi- lize these stockpiles is not acceptable. A perennial mix, similar to that which will be planted on the reclaimed surface, should be used. (see item k below). f) The statement ismade on page 13 that re-application of topsoil will occur "during the spring or fall when the moisture content is high and reapplication is somewhat easier." This is not an adviseable practice. Handling wet topsoil is extremely damaging to soil structure, and would hinder the success of revegetation. g) Mulching practices have not been described in the reclamation plan, although mulching is addressed in the response to the federal interim regulations. This discrepancy should be corrected. (2)