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6 <br /> ��ENVIRONMENTAL <br /> City of Decatur,IL SERVICES° <br /> Scope of Services/Methodology <br /> ADS will conduct a leak detection/location survey with sonic detection equipment on the City's water <br /> system.We will survey the total length of water main over 3-years(33%per year)estimated to be 495.3 <br /> miles,and monitor the system by listening directly on all hydrants and selected main line valves, b-box, <br /> and service valves with highly sensitive sound intensifying instruments. For a project of this size,we <br /> propose two days sounding of the system followed by one day of resounding and correlating at each <br /> potential leak location.This approach will provide a set of organized results for the report that can be <br /> submitted to the city each week. ADS will perform two full days of sounding the system and marking <br /> down the potential leak sounds.One day will then be taken to return to those locations to see if the <br /> sound is still present.The sound may simply be due to usage and resounding will determine whether it is <br /> a leak sound. If it is a leak sound,the location will be further investigated with the electronic correlator. <br /> ADS will thoroughly investigate the mains, hydrants,valves and/or services with an electronic leak <br /> correlator and ground microphone to pinpoint the leaks for repair. Leak locations will be marked with <br /> Precautionary Blue Paint unless otherwise noted by the City.ADS will always recommend that all <br /> identified leaks be repaired while ADS engineers/technicians are still working in the city so that the <br /> immediate area can be sounded again in case another leak may have been masked by the original leak <br /> noise. <br /> Listening distances will not exceed 500 ft.,when possible. On particularly difficult to find leaks <br /> Hydrophone sensors or Ground Mics may be deployed to assist the pinpoint of the leak. ADS will also <br /> record all defective system components—such as valves,hydrants and curb stops—as well as any map <br /> errors that are noted in the course of carrying out the field activities.We will be able to conduct the vast <br /> majority of the survey during normal working hours outlined in the RFP documentation. In areas with a <br /> high traffic volume or heavy background noise,ADS will perform this work during off-hours and will <br /> provide the City with the necessary notice. ADS will provide all necessary traffic control for this project. <br /> Equipment <br /> ADS is unique in that we use a number of industry leading technologies to perform our leak detection <br /> surveys. Our primary equipment includes the Fluid Conservation Systems(FCS)S-30 and/or the <br /> ADS/Primayer Mikron Leak Surveyor for sounding the leaks and the Echologics LT Leak or ADS/Primayer <br /> Digital for pinpointing the leaks. Echologics and Primayer are leaders in the manufacture and service of <br /> leak detection equipment.Our leak technicians use this equipment for leak surveys and emergency leak <br /> calls on a daily basis and continue to have good success with it. In those areas of the leak survey with <br /> very high traffic volume,we may use a second leak detection device to supplement the work of the <br /> Echologics LT Leak correlator. The ADS/Primayer Enigma—used by our leakage technicians on many of <br /> our most recent leakage surveys in the Midwest region—combines sound logging and correlation. Up to <br /> six correlating"pods"can be deployed in an area on hydrants or valves.The pods can be programmed to <br /> sound and correlate with each other at a particular time of day(for example,during nighttime hours <br /> when traffic and other noises are minimized).The information from the pods is then downloaded to a <br /> laptop computer and analyzed to determine if and where there are leaks In the target area. <br /> ¢choloics <br /> Primayer F6 <br /> Fluid Ceme Ia <br /> Sol*— <br />