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Page 3 Jim Monroe Patterson Pass Business Park : A comprehensive delineation of the site was conducted on March 17, 1998. Five separate potential wetland areas were identified; Patterson Run (Sheet 3),. rhea C (Sheet 3), Drainage A (Sheet 3), Drainage B (Sheet 4), and a pond (Sheet .4). Each of these areas will be discussed separately. W-ETL.AND DELII.TEATION RESULTS Patterson Run Patterson Run is an in!ermittent ephemeral drainage, varying in width from 14 to 56 feet, whir;: meanders from southwest to northeast across the site. ' This drainage flows from a culveri under the California Aqueduct. At this location, the channel is 56 feet across, which narruvvs to 30 feet across and is deeply i.-tcised, with steep banks on either side. it appears that the channel had recently been dredged at this end of the drainage, to remC excess dge sediment to improve flood control. Due to ilte presence of cattails (Tvp p•) spoils deposited at the top of the bank, it is assumed this channel was dominated by cattail. Remnant wetland vegetation on either side of the channel include cattails and rushes (Juncos sp.) located from the OHW to 3 feet up the bank. The steep banks were dominated by upland vegetation including annual rye grass (Collum mtrlt� fpt orum), wild oats (Avena ira)., fiddivneck (Amsinckia rnenziesil), bromes (Bromus diandrus, ' Bronrus ' rordaccus), and California bur clover(Medicago polymorpha). As Patterson Run meanders across the site, the channel narrows to 15 to 25 feet, and becomes less incised. The channel is dominated by cattails, curly dock (Rumex.crispus), and rushes, v.•ith an occasional willow (Salix sp.). The terrain becomes more flat, and the banks are dominated by creeping wild rye (Leymus triticoides). Agricultural practices such as discing and oat cultivation are conducted up to the edge of the banks of the drainage on either side: is At the northern end of the drainage, willows dominatedt cattails. tCreeping ory, and wild ryes curly dorninated.by creeping wild rye, rush (Juncus effusus)> dock, prickly lettuce (Lactuca serriola), rabbitsfoot grass (Polvpogon monspeliensis), and Bermuda grass(C,vnodon dactylon) grow along the sides of the channel. The top of the banks are characteristic transitional areas, with mixed upland and wetland vegetation such as prickly lettuce, wild oats, western nettles (Urtica sp.), cocklebur (Xont plum st r),n rium)Jmall Italialkali I an thistle (Carduus pycnocephalus), willowherb (Ep'labium ass. (Malvella leprosa),Jimsonweed (Datura stramonium), and rye gr When this area of Patterson Run was delineated on November 21 1997, the.bottom of the channel had deep soil cracks and the top 6 inches of the soil profile was saturated, providing ater a positive indicator for wetland hydrology. Vegetation showed evidence of flowing sediment deposits. The soils were clay loarn,.with moderately abundant mottles. All of the wetland criteria wcre met, indicating that Patterson Run qualified as a wetland area F�.MI 1 > rL% % AI IntALr C