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EXHIBIT A (Tcsultants SCOPE OF ENGINEERING SERVICES CITY OF NORTH OLMSTED, OHIO SOUTH INTERCEPTOR INFILTRATION/INFLOW STUDY If City staff finds themselves unavailable to complete certain tasks on an emergency or scheduled basis, CT can provide field services assistance during any point in the program, including: • Equipment acquisition and rental • Installation • Operations and maintenance • Data download • Data quality control review These services are outside the scope of services for this project, but are available upon request. We concur with the approach to utilize the City's own experienced staff wherever possible, but offer assistance with our own local team when needed to maintain data integrity during the metering period. This keeps the program cost affective by not having to extend the metering period due to lost data. The rain gauge and flow metering data will be incorporated into the model to analyze the hydraulic characteristics of the interceptor and correlate any system losses that may be due to bends and transitions versus issues due to 1/1 impacts. At the meters related to 1/1 impacts, a review of dry weather versus wet weather flow will be analyzed to identify the impacts of various areas tributary to the interceptor and prioritize them for future investigation. CT proposes to use SWMM software as the modeling engine for the South Interceptor system computer model. This software is available at no cost from the USEPA and is utilized by many communities for sewer system analysis. CT Consultants uses a variant of this software (PCSWMM) that is wholly compatible with the free version available from the USEPA. The model will focus on the interceptor with multiple input points for data from the flow metering. The model will undergo validation, error analysis, calibration and verification. The calibration and validation procedure will compare actual sewer flows at the meter locations resulting from measured rainfall to the modeled values. The model will then be utilized to investigate possible alternatives to convey the existing system flows through improvements to hydraulics, detention storage, or capacity. Prepared by CT Consultants, Inc. I November 9, 2017