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EXHIBIT A consultants SCOPE OF ENGINEERING SERVICES CITY OF NORTH OLMSTED, OHIO SOUTH INTERCEPTOR INFILTRATION/INFLOW STUDY The City intends to perform flow metering in the spring of 2018 beginning in March for a period of 4 to 6 months. The City has identified six (6) initial locations for flow metering the interceptor system and has the capability to add six (6) additional locations with their own equipment. The project can begin during the winter of 2017 / 2018 by building the hydraulic model first and performing a sewer system stress test to initially identify capacity issues due to size and slope versus transition or bend losses. Flow metering locations to further identify capacity issues due to 1/1 can then be identified to optimize the meter placement recognizing meter accuracy limitations inherent in metering a linear interceptor system. The Southern Interceptor is typically defined as a linear collection system interceptor as opposed to a finger collection system interceptor. A finger collection system consists of large areas of collector sewers that connect to the interceptor at defined points. There are only a couple of areas along the Southern Interceptor where this occurs. A linear collection system typically consists of collector sewers that have smaller drainage areas and connect to the interceptor at multiple points along its length. The difference in these two types of systems requires a different strategy for locating flow meters. A finger system can utilize flow meter locations on the collector sewers at connection points to the connected sanitary sewers. The impact of 1/1 for each drainage area is the value provided by the flow meter. To develop the interceptor sewer flow, flows are added at the appropriate point and accumulate moving downstream in the interceptor. A linear system can be flow metered by two methods to determine 1/1 impacts. Method 1 includes flow metering representative collector sewers along the interceptor that are specific to construction history and development type. Utilizing the representative method requires projecting flows for other similar collector pipes along the interceptor based on their drainage areas and adding them together at the appropriate location. There are many assumptions made in this method that could impact the accuracy of the anticipated flow. Method 2 includes flow metering at multiple points along the interceptor and subtracting the difference in flow between the meters. The interceptor method requires that the flow meters be properly located so that there is a significant change in flow between each meter to lessen the impact of accuracy issues that occur when subtracting flow between meters. Prepared by CT Consultants, Inc. I November 9, 2017