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1 1 l rl r 1 r 1 ~ 1 :' ) ~ I ! F I I . J alternative will follows. Alternative 2: Design a self contained interconnected Drainage System with a deep gravity drainage well. Alternative 3: Design a self contained interconnected Drainage System with the combination of exfiltration trench drains and deep drainage well to provide for both water quality and attenuation. Alternative 4: Design an interconnected Drainage System with the combination of exfiltration trench drains and deep drainage well with an emergency outfall connection. The purpose of the outfall will be to overflow the excess for higher storm events that cannot be contained within the proposed drainage system. Outfall analysis will include two options. First option: discharge the excess runoff to the FDOT drainage system that runs along the Collins Avenue. Second option: discharge the excess runoff to the intracoastal tidal waters. If outfall connection to the intracoastal is selected} then high efficiency check valves will be used to prevent any tidal waters from entering into the Citls drainage system form the high tide events. Under this option additional analysis will be conducted to select the best location in terms of cost and permitting compliance. f 1 , I , I l I Design criteria: Our design will incorporate all current design criteria as required by the Miami-Dade County Stormwater Design Standards} FDOT} FDEP for deep drainage well criteria and any regulatory agency that we may need to obtain a permit for the proposed drainage improvements. In order to optimize the design for the worst case scenario} we will utilize variable groundwater and tailwater conditions along the storm analysis for different storm events and frequencies. This will allow to identify when the maximum f100dings occurs} which is usually during the peak of the rainfall event and the maximum stages of both the groundwater and tidal stages when the discharge is taken place. By taken this design approach, we are confident that proposed drainage improvements will work under the most unfavorable conditions and has been implemented and verified in recently constructed projects that we have designed , j . I , J , J , J , J and permitted using this design methodology Permitting Agencies: Our staff has a vast experience and knowledge of per- mitting process with all locals} state and federal regula- tory agencies. The anticipated permits for this project may include a Class II Stormwater Permit from Miami- Dade Environmental Resource Department (DERML an Environmental Resource Permit (ERP) from South Florida Water management District (SFWMDL a per- mit connection from FDOT to allow for discharge into their jurisdiction} an FDEP permit for the construction of deep drainage well} a cut and fill permit from the United States Army Corp of Engineers (USACE) to al- low for discharge into their jurisdiction} a Storm Water Pollution Prevention Plan (SWPPP) in compliance with the National Pollutant Discharge Elimination System (NPDES) permitting. Since an impact to the intracoastal may occur} a Coast Guard Permit from the United States Coast Guard and Fill Nationwide Permit from USACE may be required. However} this will be minimized or eliminated altogether by choosing a location that will avoid any impact to the navigational limits as estab- lished by Coast Guard. Preliminary coordination with permitting agencies is anticipated at the early stages of the project to ensure addressing all permitting require- ment criteria and incorporate them into the proposed design. Recent Project Experience: Our company has completed several design projects and Studies similar to the City of Sunny Isles in the last two years that incorporates both design criteria and permitting requirements. The most notable are: 1- Palm Grove Improvements for the City of Miami (City Project No. B-30630L which is under construction now. Proposed drainage improvements include 800 linear feet of french drains and 7 deep drainage wells. 2- Oakland Grove Improvements the City of Miami (City Project No. B-30880L which is under permitting now. Proposed drainage improvements include 600 linear feet of french drains. 3- Evaluation of two alternatives to addre.s~ dr'!ll].age