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• 4.0 CONCLUSIONS AND RECOMMENDATIONS Almost ten yeazs after completion of reclamation, the Survey Area appeazs to support a healthy stand of perennial grasses and forbs. The site appears to be physically stable and no signs of significant erosion were observed during the sampling program. Although several noxious weeds were observed in the Survey Area, they did not comprise a significant portion of the total vegetation cover. The Survey Area currently provides wildlife habitat to the area and also provides grazing range for domestic livestock. The revegetation success study indicates that the Survey Area meets standards for herbaceous production, cool season grass diversity, perennial forb diversity, and woody stem density. The Survey Area does not meet standards for percentage cover and species diversty for warm season grasses. The reasons why the Survey Area does not meet these standards are believed to be largely related to actions taken as part of the previous reclamation program and not to depth of the topsoil layer. These deficiencies aze expected to be addressed by the reclamation program included in the Mine Permit. The vegetation cover standard was not met for the Survey Area. Several possible explanations have been developed for not meeting this standard, including soil nutrient deficiencies and grazing. Potential soil nutrient deficiencies will be identified and corrected as part of the reclamation plan. Under the reclamation plan, a soil testing program will be implemented prior to seeding and after • topsoiling to identify any soil nutrient deficiencies. The soil tests will evaluate samples for the presence of major soil nutrients, including nitrogen, potassium, and phosphorus. The analytical results will be used to develop fertilizer application rates. While the 1"992 reclamation program did include the use of fertilizer, it is not known how application rates were determined or whether an organic or inorganic fertilizers were used for treatments. It is possible that soil tests were not conducted as part of the original program and/or that mineral fertilizers were used as soil amendments. Either scenazio could help explain why soils aze now nutrient deficient. If soil tests were not conducted, sufficient fertilizer amendments may not have been applied to the reclaimed area. Inorganic fertilizers may have been readily leached from soil, which would help explain why soils aze now deficient in several macro-nutrients. Future reclamation programs should use organic fertilizers because of its potential advantages over inorganic fertilizers. Another factor that may explain variations in vegetation cover in the Survey Area and Reclaimed Area is grazing. Some of the species included in the seed mixture are known to decrease under grazing pressure. In the future, grazing activities within the Survey Area should be restricted so that the grazing does not influence monitoring results. The Survey Area also did not meet the warm season grass species diversity standazd. A possible explanation is that warm season grasses were under-represented in the seed mixture used as part of the 1992 program. The seed mixture used to reclaim the Survey Area in 1992 was comprised of 13 • percent warm season grasses and 70 percent cool season grasses. A different seed mixture has been developed as part of the Mine Permit. This seed mixture, presented in Table 14, has a higher RevegetationSurvryRepoR-RPT(626JRevl.dac/Septem6er 6, 2001 15