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Amendment Item 2 — Task 16 Unidentified Additional Services — <br /> Evaluation of City Water Production Data <br /> 1.1 Objective <br /> Evaluate the City of Everett's existing historical production data to attempt to resolve <br /> historical production metering discrepancies from the meter measuring finished water <br /> (flow element 60). Prior to being replaced it is believed that this meter was not recording <br /> water flows correctly and therefore the historical data extracted from this meter is <br /> unreliable. <br /> 1.2 HDR Services <br /> 1. Perform additional initial information gathering and review - obtain and review <br /> information from City of Everett technical staff on the potable and non-potable <br /> production system. Take the following steps to attempt to understand issues <br /> regarding the discrepancies between old and existing meters and resultant <br /> production data, and determine the relationships between existing meters to be <br /> used in the analysis: <br /> • Obtain 10 years of potable and non-potable production data for all relevant <br /> meters. Data is available from the City of Everett as an Access Database. <br /> • Obtain schematics of production system(s) that includes all relevant meters to <br /> be included in analysis. <br /> • Obtain information on the changes in the system that impact understanding <br /> and analysis of data; such as the timing of meter installation, discrepancies in <br /> meters, or deliveries of potable water to industrial (non-potable pipeline). <br /> • Develop understanding of the production system by reviewing schematics, <br /> data, and other gathered information. <br /> Meetings associated with these activities are identified in Subtask 3. <br /> 2. Take the following steps to analyze the existing information to develop an estimate <br /> of potable and non-potable water production from a combination of meters <br /> available at the treatment plant: <br /> • Study/water balance approach to identify the various meter flows that need to <br /> be added or subtracted to develop a more accurate production estimate. <br /> • Review and obtain approval of approach with City of Everett technical staff. <br /> • Extract relevant data from the MS Access database into MS Excel. <br /> • Reformat extracted data (e.g. develop annual, monthly, daily data from hourly). <br /> • Perform initial QA/QC of raw data to identify outliers: This step will be <br /> performed using simple mathematical and visual techniques. <br /> • Apply meter water balance approach. <br /> • Perform follow-up QA/QC for additional discrepancies. <br /> 3. Meetings and communications with City of Everett technical staff to support the <br /> proposed work described in Subtasks 1 and 2. One HDR employee will attend two <br /> meetings and follow-up telephone calls with City of Everett technical staff. The 1 6 <br /> meetings will be used to gather information needed to perform analysis and to <br /> Everett CWP 4 of 8 Amendment No. 1-Exhibit A-1 <br />