2009-02-03_GENERAL DOCUMENTS - C1981041

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The operator had committed within the PR-02 amendments to conduct additional vegetation studies in areas to be affected by disturbances associated with the proposed CRDA-3, but such studies were not conducted; due to the operator's subsequent decision to withdraw CRDA-3 from the permit. Less than 4 acres of additional disturbance did occur within soil borrow area CBA-2 in 2002, in association with CRDA-1 reclamation. An endangered species survey was conducted within this area prior to disturbance, but vegetation cover, production, and woody plant density sampling was not conducted within the CBA-2 borrow area. Based on visual evaluation, and given the small area of disturbance, it is the Division's determination that the greasewood vegetation type within the subject area, is adequately characterized by the New Greasewood reference area (see below), for which adequate data were obtained. No further affected area vegetation data collection is required. In the summer of 1999, a new greasewood reference area was established to replace the original greasewood reference area. The original greasewood reference area was in a relatively disturbed location immediately adjacent to the railroad grade, overland conveyor, and highline canal. The greasewood community in this location exhibited a very high cover of greasewood, with understory dominated by weedy forbs. The new greasewood reference area was established on a relatively undisturbed colluvial toe slope to the west of the Coal Creek ephemeral drainage, approximately 1500 feet northwest of CRDA-1. The new reference area is more reflective of the greasewood community found in most portions of the permit area, and better represents reclamation objectives, with higher herbaceous cover and production, and a higher diversity as compared to the original greasewood reference area. Information on the new greasewood reference area (data, narrative, and map) is presented in Appendix 10-4. Revegetation success criteria for total vegetation cover, herbaceous production, woody plant density, and species diversity are specified in Section 2.05.4(2)(e) of the application, pp. 14-19 through 14-26, as are success demonstration sampling techniques and methods of statistical comparison for the applicable parameters. The currently approved permanent seedmixes applicable to most mine areas are listed in Table 14-8; a "specialty" seedmix for harsh, saline sites is listed in Table 14-15; previously approved seedmixes used in various specified locations are listed in Tables 14-4, 14-6, and 14-9 through 14-14. Due to establishment of the new greasewood reference area, and the withdrawal of CRDA-3 proposed disturbance from the permit, narrative regarding comparison of specific reclaimed areas to particular reference areas was modified by RN-03 amendments. Revegetation monitoring and evaluation was conducted by Cedar Creek Associates, a consultant to the operator, in 2001 (Appendix 14-7). Based largely on that evaluation, certain modifications to approved sampling procedures, technical standards for revegetation success, and permanent seedmix formulations were submitted and approved via TR-38. Inter-seeding was approved for low diversity areas on the lower benches of CRDA-2, and was conducted in November 2001. Certain additional refinements of the approved seedmixes were approved in 2002. Species diversity standards were amended by TR-46 in 2005, and MR-70 approved in 2005 provided for fall herbicide treatment of cheatgrass within the North Decline reclaimed area in 2005 and 2006, along with interseeding of the treated areas following the second treatment. The interseeding was completed in February 2007. The Division approved further amendments to the revegetation plan and success evaluation criteria in association with PR-3. Areas approved for "Industrial or Commercial" postmining land use, which are Permit Revision No. 4 41 February 3, 2009