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fir• y PROJECT DESCRIPTION The A.G. Spanos Companies (Spanos)propose to restore wetlands and associated uplands on a portion of Shin Kee Tract in the eastern part of the San Joaquin Delta.The purpose of the project is to generate wetlands and special status species mitigation credit that can be used to offset impacts resulting from current and future Spanos development projects in the area.The levees at the perimeter of the site will be modified to recognize additional water interior to the Tract. Culvert crossings will be installed to maintain a trail atop the levee.The site is intended to serve as a Recreational Use by providing an extension of the nature preserve which exists to the east. Shin Kee Tract, consisting of approximately 1,055 acres, is located west of Interstate 5 and south of SR-12 in San Joaquin County.The tract is bordered by White Slough on the south and dredger cuts on the west, north, and east. The southernmost unit of the White Slough Wildlife Area(Ponds 9-13), managed by the California Department of Fish and Game(CDFG), abuts the east side of Shin Kee Tract. Spanos currently owns approximately 300 acres +/-at the east end of Shin Kee Tract and is proposing to restore wetlands and associated upland habitats on the northern one-half of that property. For planning purposes, the ultimate restoration goal has been set at about 142 acres of restored habitat within a matrix consisting of approximately 80 percent wetland and 20 percent upland habitats. The restoration site is currently protected from flooding by farm levees constructed in the late 1800's.The site is relatively flat,sloping gently toward the southwest; elevations(excluding the levees)range from about -1.5 to +2 NGVD.The property has been provided with flood irrigation facilities and is currently in agricultural production. The restoration concept is based on a meandering tidally-influenced channel design excavated to a maximum depth of about-6 feet NGVD. Excavated material will be used to construct new levees along the west and south sides of the restoration area and to build up portions of the site to about +5 feet NGVD. Normal tidal range in this area of the Delta is about -1 to +4 NGVD. With this design, some portions of the site will be permanently inundated and some portions will be above the reach of the highest high tides. The current grading concept calls for a 2:1 slope to be created along the east side of the meandering channel with a much flatter slope along the west side.The steeper slope, which will extend from maximum depth to +5 feet,will provide basking areas for giant garter snakes with escape terrain (i.e.,open water)readily available. maintenance dredging of the channel should that ever be necessary. This design will also facilitate gl g Y g Levees will be constructed within a 70-foot wide footprint.The levee crown will be 16 feet wide with 24-foot wide 3:1 side slopes.The levees will be set in about 15 feet from the property boundary. Levee height will be 8 feet above existing ground.A total of 4,100 lineal feet of levees will be constructed. The project will require grading of approximately 400,000 cubic yards of material. Cut and fill will be balanced on site; there will be no ex or import ort of material. P P The wetlands restoration concept involves bringing water onto the site from the existing man-made channel on the east side of the property.Two inlets/outlets will be created to allow free movement of water on and off of the n will provide the greatest biological value An en channel design a site with the ebb and flow of the tides. op g p gr g because fish and other aquatic organisms will be able to colonize the site and utilize restored habitats. It will also require the least amount of active management.Various means of closing off the openings,which may be necessary for initial revegetation and for management purposes,are being investigated. Once grading is complete, revegetation of the restored habitats with a variety of emergent wetland,riparian wetland and associated P upland plant communities will occur. Reveg etation will consist of planting tule plugs in P intertidal areas(about 0 to+3 feet NGVD),riparian wetland species in higher elevation tidal areas(about +3 to +5 feet NGVD)and riparian upland species above tidal elevations(about+5 feet NGVD.) Construction is scheduled to commence in the summer of 2007,with revegetation occurring during fall 2007.