R2017-26 Agreement with Crawford, Murphy & Tilly for Lost Bridge Inflow & Infiltration Reduction

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Exhibit A SCOPE OF WORK EXHIBIT A-1 CITY OF DECATUR—DEPARTMENT OF PUBLIC WORKS LOST BRIDGE NORTH (TA 3N)AND FLORIAN (TA 6) BASINS— SANITARY SEWER ALTERNATIVES ANALYSIS/SSO ELIMINATION REPORT SCOPE OF PROFESSIONAL SERVICES FOR CRAWFORD, MURPHY & TILLY, INC. BACKGROUND The United States Environmental Protection Agency(USEPA)has drafted an Administrative Consent Order(ACO) (Docket No.V-W-12-AO-21) for the City of Decatur under Sections 308(a)and 309(a)of the Clean Water Act(CWA) in regards to documented sanitary sewer overflows(SSOs),which are prohibited by the CWA. SSOs are defined by the ACO as any sanitary sewer discharge into waters of the US and into public or private property, such as backups. Target Areas(TA) of the City that have to be addressed within the ACO are the Lost Bridge North(TA 3N) and Florian(TA 6)Basins(i.e., investigation basins)which are generally located on the southeast and west central sides of the city,respectively. Lost Bridge North includes approximately 8.5 miles of separate sanitary sewer and 171 manholes serving 620 parcels. Florian includes approximately 4.0 miles of separate sanitary sewer and 90 manholes serving 470 parcels. It is noted that City of Decatur sanitary sewers flow into trunk sewers owned by the Sanitary District of Decatur(SDD)and are tributary to the SDD wastewater treatment plant. PURPOSE The following scope of professional services addresses the Sewer Collection System Alternatives Analysis for the investigation basins as outlined in the ACO. The purpose of the Sewer Collection System Alternatives Analysis is to develop and evaluate alternatives to eliminate excessive inflow and infiltration (UI)in the investigation basins causing wet weather related SSOs and property backups. Recommended actions that take all feasible steps to eliminate excessive 1/1 into the sanitary sewer collection system are to be considered. As outlined in the ACO,the Alternatives Analysis is to address the following: 1. Improvements to the existing sewer system, including repairs,rehabilitation or replacement of sewer pipes(restrictions)or lift stations 2. Construction of additional sewer conveyance capacity 3. Construction of storage basins or tanks within the system; and 4. Actions to reduce private property I/I contributions including private property inflow inspections (e.g., sump pump inspections)and/or smoke testing 5. An estimation of the cost of each alternative considered 6. An estimation of the benefit(in terms of either the 1/I in gallons removed or SSOs and property backups prevented) 7. A green infrastructure evaluation that will consider potential green infrastructure measures to help reduce and/or eliminate sources of UI Last Revised:05-15-2013 A-1