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2.0 EXISTING CONDITIONS The approximately 23-acre project site is located approximately 1.25 miles south of Interstate 580 and approximately 3 miles east of Interstate 680 within the City of Pleasanton in Alameda County. The site ranges in elevation from approximately 355 ft. (108 m) National Geodetic Vertical Datum (NGVD) in the southwest portion of the site to approximately 363 ft. (111 m) NGVD in the northeast portion of the site. Until fairly recently (last 3 to 4 years), the site was in active agricultural and supported an intensely managed farm environment (e.g., row crops). Surrounding land uses presently include residential and industrial development, old gravel quarry features -some of which now function as flood control and ground water rechazge under management of the Alameda County Flood Control and Water Conservation District -and other ruderal open space. The site has been recently converted from an active farm to a site where soil has been excavated for neazby development or stockpiled and as such supports limited habitat value consisting primarily of ruderal vegetation. Two soil types-Yolo loam 0-3% slopes and Yolo loam over gravel 0-3% slopes-were identified on the site. The Yolo soil type is considered to be awell-drained soil with slow to medium runoff. It is chazacterized as a neutral and non-saline soil. Additionally, this soil type is not considered hydric. Under current management, all the soils occurring onsite are generally disturbed. The eastern portion of the San Francisco Bay region has a Mediterranean climate with warm to hot dry summers often exceeding 90°F and cool winters as low as 35°F. Annual precipitation in the general vicinity of the site is highly variable from year to yeaz. Average annual rainfall is approximately 14.5 inches, 95% of which falls between October and April. Low rainfall, its seasonal distribution, and summer heat would have naturally selected for annual grasses and forbs, and would have precluded native trees and shrubs from occurring on the site. Stormwater readily infiltrates the soils of and surrounding the site, but when field capacity has been reached, gravitational water flows off the southwestern boundary of the site or into shallow depressions that have been created onsite. One of these depressions, occurring along the western boundary of the site, appeazs to have been created to draw water away from a temporary gravel access 5 Ironwood 55+ Biotic Evaluation Live Oak Associates, /nc.