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F. EXAMPLE PROJECTS WHICH BEST ILLUSTRATE PROPOSED TEAM'S QUALIFICATIONS FOR THIS CONTRACT (Present as many projects as requested by the agency. or 10 projects, If not specified. Complete one Section F for each proJect.) . . . 21. TITLE AND LOCATION (City and State) Florida Department of Transportation, District 2, Gainesville, FL 20. EXAMPLE PROJECT KEY NUMBER 004 22. YEARS COMPLETED PROFESSIONAL SERVICES CONSTRUCTION (If Applicable) 24. BRIEF DESCRIPTION OF PROJECT AND RELEVANCE TO THIS CONTRACT (Include scope, size, and cost) During a road construction project for SR 20 between Gainesville and Hawthorne Be Sure to Notice FL, the roadway construction contractor did not place or maintain an effective erosion control system. This resulted in the discharge of sediment laden stormwater that accumulated in adjacent wetland areas. Uncontrolled run-off of fill material from this construction site and roadway project escaped into waterways and wetlands and formed significant deposits, 3 to 16 inches over in 11 areas including wetlands and tributaries to the Lockloosa River in Alachua County Florida. This discharge resulted in excessive turbidity, burial of organic wetland soils, changes to drainage patterns, loss of wetland function, and decreased hydraulic capacity. These impacts violated State and Federal laws and responsible parties were subject to civil penalties and fines levied by Florida's Water Management Districts, the US Army Corps of Engineers, and Florida Department of Environmental Protection. Typically efforts to remove sediment from wetlands are often hindered by regulatory policies prohibiting further impacts in the form of root damage, plant loss, soil compaction, and turbidity caused by heavy excavation equipment. Manual excavation, while creating less disturbance is often slow, costly, and not entirely effective, especially in cases where the sediment plume extends far downstream. In addition, regulators require any damage resulting from sediment excavation to be repaired, adding significant cost and effort. In particularly sensitive wetlands, costs of restoring damage caused during remedial excavation can overwhelm the costs of addressing the sediment plume. For the subject project, Shaw was successful in developing low-impact sediment removal techniques using vacuum dredging. These techniques are applicable to streams, tributaries, swales, and wetlands, even in remote areas or far downstream of the sediment source. Using a combination of techniques including temporary de- watering and diversion, hydraulic scouring, and vacuum extraction, Shaw was able to precisely control the depth of sediment removal to expose the natural substrate, eliminate downstream discharge, avoid damage to root systems from cutting and soil compaction, and limit impact to surrounding environments. Using 6-inch aluminum intake tubing, the machine directly reached impact areas from the road shoulder and other locations where a stable base material was established to a distance of 30 feet. Attachment of flex tubing or 6-inch PVC piping using PVC couplings and/or flexible rubber Fernco-type adaptors was used to increase the effective length of the intake to a distance of 500 feet. Shaw's techniques have met with regulatory approval and are a preferred approach. They offer immediate cost reduction benefits in that manpower needs are greatly reduced and that it lacks a large footprint that would require post-excavation repair, maintains intact root systems along banks, has little effect on vegetation or soil conditions outside the excavation area, and does not compromise bank integrity. These attributes are particularly valuable in sensitive environments, such as forested wetlands, where restoration of impacts caused by traditional excavation techniques can be extremely difficult and costly. In emergent wetlands and marshes, post-remedial planting was conducted to replace wetland structure and function after sediment removal. Monitoring of replanting success is ongoing 7 months after installation and all areas exhibit good growth of planted specimens, recruitment of new plants from surrounding areas and no evidence of disturbance. 23. PROJECT OWNER'S INFORMATION a. PROJECT OWNER b. POINT OF CONTACT NAME c. POINT OF CONTACT TELEPHONE NUMBER 386-961-7582 · Innovative use of common vacuum equipment - Shaw has pioneered techniques for remediation of wetlands and waterways impacted by sediment run-off from construction sites. · Time savings for client. · Solution that was environmentally friendly; limited impact to natural vegetation and contours. ~ a FOOT 2 Jenny Sargent STANDARD FORM 330 (6/2004) PAGE F-1