R2022-114 Resolution Authorizing a Professional Engineering Services Agreement with INTERA Inc. for DeWitt County Wellfield Improvements, City Project 2022-05

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EXHIBIT BURNSMC.D0NNEL.L._ Deliverables: MACP condition assessment summary TASK 3: SEWER PIPE CONDITION ASSESSMENT BMcD will review, document, and summarize findings related to deficiencies and existing conditions of approximately 22,600 LF of sewer pipe,whether structural issues (e.g. crack,fracture,broken, etc.), defects(deposits,roots, infiltration,obstacles,etc.),or features (taps, intruding tap, etc.). Pipe condition assessment work will be performed in accordance with NASSCO PACP standards. It is assumed that the City will provide CCTV data electronically in a suitable format(i.e. MP4,WMV,etc.) to be reviewed at BMcD offices. After the sewer has been comprehensively televised,BMcD will identify any sewer pipe locations that may require manned entry for more detailed inspection and assessment. Since it is not known how many pipe locations will require manned entry,this will be addressed by an allowance(see Task 7). BMcD will also pay particular attention to potential sags in the sewer, especially in the vicinity of Martin Luther King Jr. Drive between Prairie Avenue and Wood Street,which may be contributing to the odor issues in the area. Deliverables: PACP condition assessment summary TASK 4: WASTEWATER SAMPLING AND ODOR ANALYSIS With the City's assistance,BMcD will perform a wastewater sampling and analysis program in order to more fully evaluate and analyze the odor challenges the City is experiencing in the downtown area, especially along Martin Luther King Junior Drive,between Prairie Avenue and Wood Street. Wastewater odors are caused by sulfur-based(hydrogen sulfide,methyl mercaptan) or nitrogen-based compounds (ammonia,trimethylamine), organic acids(acetic, formic acid), or carboxylic acids(propionic,butanoic acid),Volatile organic compounds(VOCs) (toluene,xylenes), aldehydes (acetaldehyde, formaldehyde) and ketones. Although sulfur compounds typically dominate odor complaints,ammonia can become the dominant odor contributor in high pH or high temperature conditions. In summary,we recommend that the City's testing program include the following parameters: • Sulfide • Ammonia(as nitrogen) • pH (real time) • Temperature(real time) • Oxidation reduction potential/ORP(real time) We recommend that the City rent(or buy) and install a single probe for real time monitoring of sewage pH,temperature, and ORP.Based on our initial discussions with vendors(e.g. Fondriest, 888-426-2151), it will be more economical to purchase,rather than rent, a probe. In both cases, BMcD will assist the City in identifying the appropriate probe to rent or buy. The sampling will be performed at three separate locations, downstream of both Tate and Lyle and the dairy plant, and where odors have been documented to be very high(i.e.past manhole 37-100). The work will be divided between BMcD and the City(or City contractors/consultants). BMcD will perform the following work: 1. Recommend the final sampling point location. 2. Analyze and evaluate the data. 200 W. Adams Street\Suite 2700\Chicago, IL 60606 A-3 0 630-724-3200\F 312-223-0920\burnsmcd.com