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<br /> City of Everett, Public Works Department, Water Pollution Control Facility <br /> <br />BIOSOLIDS SAMPLING & ANALYSIS PLAN 7 <br /> <br />Analytical Resources Incorporated (ARI) is an independent and Ecology accredited laboratory located in <br />Tukwila that is used for: <br />• Nutrients <br />o Nitrite/nitrate <br />o Ammonia <br />o TKN <br />• TCLP Metals – if needed for disposal purposes <br />3. Biosolids Sampling <br />a. Sampling in situ biosolids for metals, VAR, and Pathogens <br />In situ sampling is completed in the AC2, Recirculation Channel, and Oxidation Pond to monitor metals <br />and pathogen density. VAR testing is completed annually at least 40 days prior to contract start date in <br />February to accurately test the area to be dredged, dewatered, and hauled. Samples for metals, <br />pathogens (fecal coliform), and total solids are taken three times a year in AC2 and Recirculation <br />Channel. Samples taken in September are provided to contractors who bid on that year’s dredging <br />project. Samples taken in January represent the area to be dredged, dewatered, and hauled. Total solids <br />and sampling in May are used in general tracking and monitoring for the COE Biosolids Program. The <br />Oxidation Pond has been characterized through previous sampling but is still sampled annually to track <br />any changes to their quality. <br />Sampling for metals, fecals, and total solids takes 3 days in the Oxidation Pond, 2 days in AC2, and 1 day <br />in the Recirculation Channel. VAR must be sampled on a separate day for each the AC2 and Recirculation <br />Channel. <br />The full SOP for In -Situ Biosolids Sampling is linked. <br />b. Sampling dewatered biosolids for fecal coliforms and nutrients <br />Dewatered biosolids have the potential for pathogen regrowth. In addition to sampling in-situ biosolids, <br />fecal coliform sampling is conducted after dewatering and before land application. This ensures <br />biosolids meet regulatory requirements for pathogen reduction. <br />Biosolids are stockpiled at the northwest end of the biosolids pad delineated by ecology block walls. <br />About 2,000 dry tons of solids fit in this area. <br />Fecal coliform testing: <br /> <br />1) On the Monday immediately following the start of dredging operations, existing piles are <br />sampled in seven locations for fecal coliforms. Samples are taken instantaneously and <br />delivered to EEL within the holding period. <br />2) One week later and every following Monday, another seven fecal coliform samples are <br />taken. These samples are taken from the following locations: <br />A) Two samples are from piles already sampled for fecal coliforms.