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1-5 the 100-year flood-flow of 1,025 cubic feet/second (cfs) within its banks with an additional one foot of freeboard. In the event that a 500-year flood occurs (1,100 cfs, according to FEMA Flood Flows), the excess flow will spill over the northern bank and into the adjacent farm land, rather than affecting Forward Landfill. Based on the realignment of the North Fork of South Littlejohn's Creek, the landfill property is not located within the predicted elevation of the 500-year flood zone. Therefore, the existing realignment does not require an assessment for potential erosion or saturation of the landfill. The South Fork of South Littlejohn's Creek runs south of and adjacent to the southern perimeter of the refuse footprint of the landfill. From the FIRM map (Map No. O6O77C Panels O635F and O63OF), the existing South Fork of South Littlejohn's Creek is labeled as "Zone A0, (Depth 1)", indicating depths of one foot, and Zone AE, indicating base flood elevations within the creek. These current flows are very slow and non-erosive and as a result, will not inundate or potentially erode the adjacent creek or inundate the landfill. The predicted elevations from the 500-year flood event range from 40.5 feet on the southwest edge to 43 feet on the east edge of the landfill along Austin Road and this level is only one to two feet higher than the toe of existing landfill slopes. The existing South Fork of South Littlejohn's Creek was designed to channel the 100-year flood flow of 1,550 cfs within its banks and an additional one foot of freeboard. In the event that a 500-year flood occurs (1,700 cfs, according to FEMA Flood Flows), the excess flow will spill over the southerly bank and into the adjacent area, rather than impact the Forward Landfill. The South Fork of South Littlejohn's Creek alignment is also a very flat gradient, 0.0006 feet per foot; therefore, erosion is not a significant concern. 1.7.4 Evaporation The estimated annual evaporation for the site is 78.43 inches based on Pan A evaporation data recorded between 1919 and 1968 at Oakdale Woodward Dam (Station No. BOO 630500, latitude 37°51'28", longitude 120°52'42", elevation 215 feet above mean sea level [amsl]), located approximately 13 miles southeast of the site (California Department of Water Resources, 1979). A minimum mean monthly evaporation of 1.14 inches has been calculated for December and January, and a maximum mean monthly evaporation of 14.69 inches has been calculated for July. 1.7.5 Wind During summer periods, winds usually originate from the north end of the San Joaquin Valley and flow in a south-southeasterly direction through the valley and Tehachapi pass, and then into the neighboring Southeastern Desert Air Basin. During winter months, winds occasionally originate from the south end of the valley and flow in a north-northwesterly direction. During winter months, the valley experiences light, variable winds, less than 10 Forward Resource Recovery Facility SWT Engineering Transfer/Processing Report-November 2014 z:\prcjects\allied waste\forward\resource recovery facility\5 yr permit rvw 2013-14\tpr 2014\text\secl.doc