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WATER TESTING RESULTS During the past year, we have taken 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, 2018. 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) MCLG AMOUNT DETECTED RANGE VIOLATION TYPICAL SOURCE Bromate (ppb) 2018 10 (running annual average) 0 4 (running annual average) ND - 11 (individual measurements) No By-product of drinking water disinfection Chloramines (ppm) 2018 MRDL = 4 (running annual average) MRDLG = 4 3.1 (running annual average) 2.0 - 4.0 (individual sites) No Water additive used to control microbes Fluoride (ppm) 2018 4 4 0.81 No range 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 Acides (HAAs) (ppb) 2018 60 NA 15 (Maximum LRAA) 4 - 20 (individual sites) No By-product of drinking water disinfection Trihalomethanes (THMs) (ppb) 2018 80 NA 51 (Maximum LRAA) 23 - 66 (individual sites) No By-product of drinking water disinfection Total Organic Carbon (removal ratio) 2018 TT = removal ratio of >1 NA 1.47 (running annual average) 1.25 - 1.86 (range of monthly) No Naturally present in the environment Turbidity (NTU) 2018 TT=1 NTU and 95% of samples <0.3 NTU NA 0.18 NTU and 100% of samples <0.3 NTU 0.01 - 0.18 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. SECONDARY SUBSTANCES SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED HIGHEST LEVEL ALLOWED (SMCL) MCLG AMOUNT DETECTED RANGE VIOLATION TYPICAL SOURCE Sulfate (ppm) 2018 250 NA 40 No range No Runoff/leaching from natural deposits; Industrial wastes UNREGULATED SUBSTANCES SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED HIGHEST LEVEL ALLOWED (MCL) AMOUNT DETECTED RANGE VIOLATION TYPICAL SOURCE Bromodichloromethane (ppb) 2018 N/A 15 No range N/A By-product of drinking water disinfection Bromoform (ppb) 2018 N/A 4.4 No range N/A By-product of drinking water disinfection Chlorodibromomethane (ppb) 2018 N/A 17 No range N/A By-product of drinking water disinfection Chloroform (ppb) 2018 N/A 8.3 No range N/A By-product of drinking water disinfection Sodium (ppm) 2018 N/A 35 No range N/A Naturally occurring