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GEI Consultants | City of Sunny Isles Beach | RFQ 26-07-01 49 <br />St. Augustine Upland & Marina Redevelopment <br />St. Augustine, FL | Confidential Client <br />GEI staff performed a site investigation that allowed segregation of the <br />sediment and off ered a beneficial reuse, rather than disposal of the <br />sediment. This solution saved the client $1M. <br />This had been a manufactured gas plant (MGP) site in operation since 1885. It is a Region IV <br />former Superfund Site, and marsh removal was performed under ACOE Dredge and Fill Permit. <br />The location on the San Sebastian River in the historic downtown St. Augustine site necessitated <br />public and city government involvement. <br />85K tons of tar-impacted soil and sediment was removed in 2001 with 22 million gallons <br />of groundwater treated and 2.2 acre wetland restoration. The project encompassed deep <br />excavations in tidally influenced marsh. <br />When a developer purchased the property in 2005, GEI led an innovative investigation and <br />EPA negotiations that allowed a layered approach for dredging of an additional 85k tons (70% <br />impacted) of sediment to construct an 85-slip marina basin to -8.9 National Geodetic Vertical <br />Datum (NGVD) and dredging of sediment for access to the river’s navigable channel. The <br />remediation proceeded in horizons which allowed segregation of material for disposal and <br />beneficial reuse (~ 25,000 tons) saving the client over $1M in transport and disposal costs. <br />Over-excavation at floor of basin was performed to -13 NGVD and basin elevation restored to -8.9 <br />NGVD by capping with a combination of sand cap and sand/geo-membrane combination cap. <br />Scour calculations in support of capping remedy was provided in the work plan to EPA. <br />The EPA has provided no further action certification for soil and sediment. Ongoing annual <br />groundwater monitoring and reporting and negotiations with EPA and FDEP are underway to <br />secure an NFA for groundwater to close out the site. <br />DATES <br />2000-Ongoing <br />KEY ELEMENTS <br />• Feasibility (EE/CA) <br />bathymetry, design, <br />contracting, oversight, <br />groundwater monitoring <br />• Work under Corps permits, <br />beneficial re-use of <br />sediments