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Permit M77-424 Amendment 1 <br />Exhibit J <br />Page 2 of 3 <br />predominant vegetation species include shadscale (Atriplex confertifolia), snakeweed <br />(Gutierrezia sarothrae), a small sagebrush species (Artemisia arbuscula?), and the <br />grasses galleta grass (Pleuraphis Ton.), and cheatgrass (Bromus tectorum L.). <br />The alluvial bottom land vegetation community is common along the valley floor which <br />includes the water transmission pipeline alignment from its origin at the former Heater <br />Treater (Area I S) to lower elevations within a mile of the evaporation pond. As <br />described in the original Exhibit J, this vegetation community is brush-dominated. The <br />upper elevations of this community, in the area of the former Heater Treater, consist <br />predominately of big sagebrush (Artemisia tridentata) and rubber rabbit brush <br />(Crysothamnus nauseous) of the alluvial bottom land community. Some fourwinged <br />saltbush (Atriplex canescens) was also observed. Estimates of cover for the alluvial <br />bottom land vegetation community are between 30 and 80 percent and exhibit heights of <br />up to 8 feet (big sagebrush). Alluvial bottom Land vegetation exists almost exclusively in <br />the Happle soil type within the affected lands around the upper pipeline. <br />The lower elevations of the alluvial bottom ]and community in Section 29, T7S, R97W, <br />just north of the evaporation pond, are characterized by a greater percentage of shadscale <br />(Atriplex confertfolia) and greasewood {Sarcobatus vermiculatus). Estimates of cover <br />for the shadscale-greasewood shrublands vegetation community are between 25 and 70 <br />percent and contain plant heights of up to 5 feet (greasewood). The shadscale- <br />greasewood shrublands span the Happle, Biedsaw, Sunup, Barx, and Dominguez soil <br />types within the affected lands around the lower pipeline and the evaporation pond. <br />In the vicinity of the upper section of the water transmission pipeline, slopes flanking the <br />alluvial bottomlands are chazacterized by a brushland-dominated area that is mixed with <br />stands of pinyon pine and juniper trees. The brushland component is comprised mainly <br />of gambel oak (Quercus gambelii), true mountain mahogany (Cerocarpus montanus}, <br />service berry {Amelanchier alnifolia), rubber rabbitbrush {Crysothamnus nauseous), and <br />snowberry (Symphoricarpos). This vegetation community is most commonly evident on <br />the hillslopes immediately surrounding the water transmission pipeline, just outside of the <br />narrow alluvial bottom lands vegetation community boundary. With the exception of the <br />unique grass-prevalent communities on the nose of ridges below the Mahogany Ledge, <br />understory vegetation is sparse and geologic erosion rates aze moderately high. On <br />steeper slopes, soils derived from weathered shales are relatively uncompacted and loose, <br />and soils on more moderate slopes typically are desiccated, moderately compacted, and <br />support limited vegetation. North-facing slopes along the pipeline azea are more densely <br />vegetated than their south-facing counterparts. Estimates of cover for the brushland- <br />dominated vegetation mixed with pinyon pine and juniper range between 20 and 90 <br />percent with plant heights between 7 and 8 feet (brush) and 12 feet (pinyon pine and <br />juniper trees). The brushland-dominated vegetation mixed with pinyon and juniper trees <br />exists dominantly within the Happle, Parachute-Irigul-Rhone, and Tosca soil types that <br />exist on the slopes supporting this community. <br />At elevations between 7,000 and 8,000 feet on the highest reaches of the slopes <br />surrounding the affected lands, a transition occurs from brush-dominated vegetation <br />