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8 2 0 2 0 W A T E R Q U A L I T Y R E P O R T WATER TESTING RESULTS Each year we take thousands of water samples to determine the presence of any radioactive, biological, inorganic, volatile organic or synthetic organic substances. The table below shows only those substances that were detected in the water. Unless otherwise noted, the data presented in the table below is from testing performed from January 1 to December 31, 2020. The EPA and the State allow us to monitor for certain substances less than once per year because the concentrations of these substances are not expected to vary significantly from year to year. In these cases, the most recent sample results are included, along with the year in which the sample was taken. Some of the data, though representative of the water quality, is more than one year old. REGULATED SUBSTANCES SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED HIGHEST LEVEL ALLOWED (MCL) HIGHEST LEVEL GOAL (MCLG) AMOUNT DETECTED RANGE VIOLATION TYPICAL SOURCE Bromate (ppb) 2020 10 (running annual average) 0 8 (running annual average) 1 - 4 (individual measurements) No By-product of drinking water disinfection Chlorine (ppm) 2020 MRDL = 4 running annual average) MRDLG = 4 2.05 (running annual average) 0.67 - 2.91 (individual sites) No Water additive used to control microbes Chloramines (ppm) 2020 MRDL = 4 (running annual average) MRDLG = 4 3.05 (running annual average) 1.23 - 3.96 (individual sites) No Water additive used to control microbes Fluoride (ppm) 2020 4 4 0.41 ND - 0.82 No Erosion of natural deposits; Water additive that promotes strong teeth; Discharge from fertilizer and aluminum factories Gross Beta (pCi/L) 2017 50 0 4.2 No range No Decay of natural and man-made deposits Haloacetic Acids (HAAs) (ppb) 2020 60 N/A 16 (Maximum LRAA) 10 - 21 (individual sites) No By-product of drinking water disinfection Trihalomethanes (THMs) (ppb) 2020 80 N/A 40 (Maximum LRAA) 26 - 47 (individual sites) No By-product of drinking water disinfection Total Coliform Bacteria (% positive samples) 2020 5% 0% 0.77% 0 - 0.77% No Naturally present in the environment Total Organic Carbon (removal ratio) 2020 TT = removal ratio of >1 N/A 1.62 (running annual average) 1.32 - 1.92 (range of monthly) No Naturally present in the environment Turbidity (NTU) 2020 TT=1 NTU and 95% of samples <0.3 NTU N/A 0.09 NTU and 100 of samples <0.3 NTU 0.02 - 0.09 No Soil runoff SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED HIGHEST LEVEL ALLOWED (AL) HIGHEST LEVEL GOAL (MCLG) AMOUNT DETECTED (90TH PERCENTILE) SITES ABOVE AL/TOTAL SITES VIOLATION TYPICAL SOURCE Copper (ppm) 2018 1.3 1.3 0.121 0/60 No Corrosion of household plumbing systems; Erosion of natural deposits Tap water samples were collected for lead and copper analyses from sample sites throughout community. In the 2018 study, no lead was detected in any of the samples.