2014-10-21_REVISION - M1988044 (5)

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TR-07 RECLAMATION PLAN Topsoil (Plant Growth Medium) Replacement Requirements DEFINITION OF PLANT GROWTH MEDIUMAS USED IN THIS PLAN. Soil is considered to be the primary plant growth medium. In most situations, soil is the darker material that is removed initially from the area to be mined. OVERVIEW: Replacement of a plant growth medium is vital to the success of the reclamation program. Without a suitable growth medium revegetation will be difficult to accomplish. It can still be successful, but it is far more likely to fail and often requires a great deal more time for the vegetation to fully develop. It is important to remember that the complete growth medium includes not only the topsoil but also what is under the topsoil. Excessive compaction of the subsoil can be quite harmful to the revegetation. Compacted subsoils are difficult for the plants to penetrate with their roots and often result in shallow rooted vegetation that cannot sustain itself during dry periods and usually exhibits low productivity and density. Many of the grasses and forbs to be planted, as well as those species that will invade the revegetation areas, can develop very deep root systems. Many native prairie grasses have root systems that can extend as far as eight feet into the soil, although generally most of the root mass is in the upper one to four feet of the soil. If only a few inches of soil is placed on top of compacted material, initial growth may be good, but in subsequent years it will often decline. Eventually the vigor of the plants as well as their reproduction will become marginal. At that point, wind and water erosion begins to destroy the most desirable vegetation and the ever versatile and undesirable weeds can become the dominant vegetation. To avoid this long range decline it is important that the subsoil not be too tight and there be a zone a few inches thick where the topsoil and subsoil tend to blend into each other. Therefore, as described previously, it is important to have a rough surface on the top of the subsoil and insure that compaction is not too great. As a rule, if water puddles on the top of the subsoil and requires more than a few minutes for a quarter of an inch of water to soak into the subsoil then the subsoil probably is too tight. In that case, additional ripping of the subsoil may be required. However, if the ridging of the surface of the subsoil is properly done, the porosity of the upper layers of the subsoil will very likely be high enough to allow for good water absorption. REQUIREMENT 11: The primary plant growth medium (topsoil or other suitable materials) shall be spread to a minimum depth of ten (10") inches. (TR-07 Note: As the area to be mined has abundant and fairly deep soils, this depth should not be limiting.) REQUIREMENT 12: The final surface of the soil shall be left rough and not smoothed. The general direction of ridging of the final surface will parallel the contours of the slope. Coal Creek Sand Resource Amendment 3 (2005)- M-1988-044 Exhibit E Page 12