In 2008 and 2009, EPCOR Water Services Inc. conducted a systematic lead samplingrnprogram in the City of Edmonton that focused on the 5,600 residences that have leadrnservice lines (LSLs). Sampling protocols followed the Guidance on ControllingrnCorrosion in Drinking Water Distribution Systems. Tap water from 3975 homes werernsampled and analyzed. The long-term goal is to replace all lead service lines. In thernmeantime, EPCOR has offered to provide all residences with LSLs with point-of-usern(POU) devices to reduce exposure to lead in the drinking water. Two types of POU filtersrnwere provided: a faucet-mounted (FM) filter or a pour-through (PT) pitcher. Somerncustomers choose to use their own water purification systems.rnIn this project the efficiency of lead removal by the POU devices at customer’s taps wasrnstudied. A total of twenty three residences where POU devices were provided werernsurveyed and the samples were collected and analyzed for lead concentrations in both thernpre- and post-POU device water. All POU devices, if used properly, were efficient in thernremoval of both dissolved and particulate lead from the tap water. The lead levels in thernpost-POU device water samples were found to be less than 0.005 mg/L (the MAC ofrnGCDWQ is 0.010 mg/L). A positive correlation was found between the percentagernremoval of lead and the particulate iron concentration in the tap water. The efficiency ofrnremoval of lead, copper, zinc and iron by the different POU devices was compared.
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