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Peabody Twentymile Coal Company 2005 Fish Creek AVF Riparian Vegetation Monitoring Twelve permanent transects were established at random locations running perpendicular to the stream channel and crossing the entire valley floor in 2003. Six additional permanent transects were established in 2005 at random locations directly northeast of the original transects above mining panels 16 and 17. The 2005 transects also run perpendicular to the stream channel and cross the entire valley floor (Map 1. 2005 Additional Monitoring Transects). For all transects, start and endpoints were established on either the Tl banks or terrace several feet above the 100-year floodplain to help ensure the markers are not washed out by seasonal flooding events. Their locations were staked in the field with steel T-posts or fiber-glass posts and GPS surveyed. Due to extensive agricultural use in the study azea and the end goal of establishing the effects of subsidence, factors used to define community types were modified to better suit this study. The Forest Service defined community types outlined in the GTR are based on vegetation communities common in natural ripazian azeas in which vegetation has not been significantly altered by anthropogenic activities (i.e. agriculture). The azea to be surveyed at TMCC has been heavily influenced by agricultural activities and therefore, the native vegetation communities types identified and used by the USFS were not applicable. Furthermore, the Forest Service methodology focuses on ascertaining the effectiveness of management practices in order to draw comparisons with potential natural communities that could exist in an ideal healthy ripazian complex for a given azea. Since monitoring at TMCC focuses on composition and distribution, rather than estimated potentials, the vegetation community descriptions and methodologies have been modified to fit this site's conditions and evaluation objectives. To facilitate implementation and achieve consistent results on an annual basis, vegetation community sub-types were developed in 2003 based on dominant vegetation chazacteristics, while ignoring minor species components. These sub-types were then consolidated into community types based on shazed inherent qualities (Table 1). For example, sparsely vegetated mud flats and eroded stream banks may have Cazex species, Juncus species, or a combination of both. Since both species aze strongly influenced by the effects of seasonal flooding and their proximity to ground water, both were included in the "Riparian" community type. Likewise, smooth brome (Bromus inermis) and Habitat Management, Inc. Page 3 3/14/2006