2002-07-08_GENERAL DOCUMENTS - M2002004 (3)

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Physically, the reconstructed soil would resemble those associated with Sagebrush - grasslands with deep effective root zones but modest genetic soil materials (Figures 3). To expect greater diversity beyond the inherent richness of the Sagebrush grassland and the reclamation seed mix would be unreasonable. A possible reclamation plan that would, in the view of the MMD, lead to successful achievement of the post -mine land use might include the following. The re- establishment of Pinyon - Juniper woodlands would be both difficult and of questionable value for the mule deer winter range land use, and the PJ type is abundantly available on unmined lands in the area. Reclamation that emulates the PJ- chained type could be accomplished by establishing a half -dozen shrub species, along with four or five taxa each of relatively noncompetitive grasses and forbs. Since spoil materials are not consolidated enough to be considered paralithic (Keck et al., 1993), this community may require a thin veneer of topdressing ( <2 ") over very coarse soil substitute materials on post -mine uplands to replicate the shallow, rocky premine soils. These upland sites would be slow to develop vegetative cover, but a fairly high percentage of coarse fragments would help stabilize the steeper slopes. A somewhat less diverse, but more productive, sagebrush - grassland revegetation could be readily established using standard reclamation techniques of seeding shrubs and predominantly warm season grasses into relatively deep soils (6 -12 ") on gentle lower slopes with north and east aspects. A cool season native grassland type on deeper soils would provide spring forage on south and west aspects. In place of the erosive greasewood bottomlands, reclaimed swales and bottoms ( >12" topsoil) could be seeded with more aggressive, alkali- tolerant (and perhaps non- native) wheatgrasses, ryegrasses, and rhizomatous forbs. Within this matrix, occasional rock piles, ledges, talus slopes, and small depressions would further enhance vegetative diversity and wildlife habitat. The past 20 years of coal mine reclamation history has shown that if enhancing diversity requires an excessive amount of paper work, it rarely happens. The key to making the plan become reality is to create a framework that will allow the operator to construct the various reclaimed communities and features without the need for constant permit modification, and that simultaneously gives the regulatory authority assurance that the reclamation plan is being followed. Narrative descriptions of the topographical settings and the approximate sizes that will be targeted for the reclaimed communities and features give the operator more flexibility than maps. Adequate detail should be provided in the reclamation plan so that an inspector can verify that an approved procedure was or is being used at any given location. Establishing different technical standards or reference areas for comparison with each reclamation community will probably be advantageous, particularly with respect to stocking and production. As seen in Table 1, premine communities as visibly different as Pinyon-Juniper and Grassland may share fifty percent of their species composition. Communities with more similar physiognomy are even more similar in terms of species makeup. It seems unlikely that revegetation efforts would result in greater inter - community (beta) diversity than existed prior to disturbance of "native" communities. The establishment of inter - community species diversity 70 60 • 50• 20 10 0 Pinyon-Juniper Saga Grassland OraasawoodlSaga d P•J Chained Orthsnts Orthid a Argid Fitments Figure 3: Soil depth along a topographic gradient in NW New Mexico. Genetic (A & B) horizons are clear portion of bars. Shaded portion is the effective depth of 1 1