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Exhibit' A" impounding wetlands proved to be an effective method of mosquito control, the practice disconnected wetland habitat from the lagoon estuary, to the detriment of estuarine species. In recent years, efforts have been made to "re -connect" these impoundments to the lagoon via culverts with flap -gates, which improves habitat while still affording seasonal flood control. Ditching and the construction of impoundment dikes have altered the natural shallow -sloping topography of the mangrove swamp, and diverted sheet flow drainage patterns. West of the impoundment areas, naturally flat topography is disrupted in a few locations by the construction of roads, jeep trails and drainage ditches, but remains generally intact. The original ORCA project area contains two impounded estuarine wetlands: "South Vista Royale" (Impoundment #18) and "North Vista Royale" (Impoundment #19). The South Vista Royale impoundment is approximately 133 acres. Construction of the impoundment occurred in 1958 and 1963. Management of the impoundment has consisted of seasonal flooding during spring and summer since 1958 via the use of a 6,000 gpm manually operated diesel pump. In the mid 1990s, the Indian River Mosquito Control District, using Surface Water Improvement and Management (SWIM) funds,, re -connected the impounded wetlands to the Indian River by installing culverts with flap -gates for rotational impoundment management (RIM). The North Vista Royale impoundment is approximately 52 acres in size and was impounded in 1957. Management of the impoundment from 1957 to 1976 consisted of seasonal flooding during the spring and summer by use of a manual pump. To date, the North Vista Royale impoundment has not been converted to RIM and is still seasonally pumped. The original ORCA property contains approximately 233 acres of wetlands, ±185 of which are impounded for mosquito control purposes. The Flinn Tract adds an additional ± 18 acres of wetland habitat, approximately 15 acres of which is impounded. The SJRWMD Indian River Lagoon Basin Land Acquisition Study (Gurr et al., 1990) characterizes the property as "located in the Indian River Lagoon Sub -basin IIID draining directly into the Indian River Lagoon between Sebastian Inlet and Fort Pierce Inlet". An FDOT drainage ditch flows through the original property from U.S. 1 to the Indian River. On the Flinn Tract, an FDOT drainage ditch conveys runoff from Indian River Boulevard to the ditch surrounding the impoundment. According to the Gurr study, the subject property has approximately 500 acres of off-site contributory drainage, and this drainage is conveyed through the wetlands portions of the site by a series of ditches and channels. Sheet flow drainage through the uplands portion of the site is intercepted by a ditch and brought into the wetlands. A portion of the upland area of the original project area (approximately +15 acres) is scrubby flatwoods with moderately well drained soils, allowing for good percolation of rainfall and direct recharge of the Surficial Aquifer. Groundwater recharge occurs in the maritime hammock communities on the original tract and on the upland portion of the Flinn Tract, although the soils in the maritime hammock community are less well drained than the scrubby flatwoods soils on the original parcel. SOILS The Soil Survey of Indian River County (USDA SCS, 1987) depicts four soil types on the ORCA property, summarized as follows: 7