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` I A. M . ENGINEERING AND TESTING, INC. d Geotechnical Exploration for Stormwater Management Planning \ Indian River County Parks Maintenance Complex , IRC Project No . 0710 A. M. Engineering Project No . PSL 1825 -2 FINDINGS The terrain at the project site was relatively flat . The grade at the project site was estimated to be even with 77`h Street at the time of our explorations . Vegetation at the site included pines, palmettos, oaks, shrubs and some cleared areas . A 3 -foot deep swale ran along the south side of the site, and the Lateral "G" Canal along the east side. Based on the spot elevations in the Site Plan prepared by Carter Associates , Inc . (not dated), the ground surface in the proposed pond sloped up from approximately elevation 18 . 5 feet on the north end to 20 feet on the south end . The bottom of the adjacent Lateral "G" Canal was approximately 13 . 5 feet, and the banks were between elevation 20 and 21 feet. The ground surface sloped down from elevation 22 feet on the west side of the site to below 19 feet in the northeast corner where the proposed pond is located. The subsurface soils encountered in the borings consisted of fine sand with minimal silt from the existing ground surface to the bottom of the borings at depths of 11 feet. These findings were consistent with the borings performed throughout the remainder of the site. Ground water was encountered at 5 and 3 '/4 feet below existing grade at the completion of the borings, approximately elevation 15 feet . The water level in the Lateral "G" Canal was approximately 6 feet below existing grade; about 2 feet of water were observed. The elevation of the water surface was between 14 and 15 feet. It should be noted that there were heavy downpours in the area the night before our field explorations, ddd USGS TOPOGRAPHICAL AND USDA SOIL SURVEY INFORMATION we reviewed the USGS 7 . 5 -minute series quadrangle topographic map of the area, entitled Vero Beach . The map was revised based on aerial photographs taken in 1983 . The USGS map showed the project site is located in a relatively flat, low, wooded area with an elevation between 15 and 20 feet NGVD . The site is between the Atlantic Coastal Ridge on the east and the slightly higher savannas on the west. A mine or quarry with two lakes/pits is east and southeast of the project site; the water surfaces are between elevations 20 and 25 feet NGVD . The Lateral "G" Canal is located east of the project site and there are several small lakes and other canals in the area. The site is shown on sheet number 21 of the Soil Survey of the Indian River County Area, Florida, issued by the U . S. Dept. of Agriculture in January 1987 . According to the Soil Survey three soil types occur within the area of the project site: Myakka fine sand (5) covers the western portion of the site, EauGallie fine sand (3) the majority of the eastern side of the site, and Pomello sand, 0 to 5 percent Slopes (21 ) the northeastern and southeastern edges of the site. It should be noted that the Soil Survey generally extends to a maximum depth of 80 inches (approximately 6'/4 feet) below ground surface and is not indicative of deeper soil conditions. The USDA Soil Survey describes Myakka fine sand and EauGallie fine sand as nearly level, /— poorly drained soils on broad flatwoods. The water table with unimproved drainage is within 10 2