2000-02-10_GENERAL DOCUMENTS - C1981041

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the margins of the riparian zone, and along ephemeral and intermittent drainages and adjacent colluvial toe slopes. During 1982, the permittee selected three cotntnunity study areas [o represent communities present prior [o disturbance by mining. These study areas encompassed a greasewood shrubland community, a shadscale shrubland community, and a mixed greasewood shadscale community. During the summer of 1982, the study areas were sampled for vegetative cover, herbaceous production, woody plant density, species diversity, and threatened and endangered species. After review of the community character, it was determined that these study areas would serve as reference areas for revegetation success criteria for cover and production for areas previously disturbed. Various issues of concern were identified by the Division during the mid-term review of 1995 and subsequent PR-02 review, including questions regarding the applicability of the original vegetation study areas to serve as reference areas for all current and proposed future disturbance sites. Modifications [o revegetation success demonstrations, seedmixes, and various aspects of the revegetation plan were requested, along with an updated endangered plant survey covering areas of proposed future disturbance. All issues of concern raised by the Division during the PR-02 review were adequately addressed. 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. Up to four acres of additional disturbance may occur within soil borrow area CBA-2. An endangered species survey was conducted within this area, 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 o[ 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 (orbs. 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 reflectwe 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 approved permanent seedmixes are listed in Table 14-4. Due to establishment of the new greasewood reference area, and the withdrawal of CRDA-3 proposed 4l