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6 2 0 1 7 W A T E R Q U A L I T Y R E P O R T REGULATED SUBSTANCES SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED HIGHEST LEVEL ALLOWED [MCL] HIGHEST LEVEL GOAL [MCLG] AMOUNT DETECTED RANGE DETECTED VIOLATION TYPICAL SOURCE Bromate (ppb) 2017 10 0 2.2 ND – 5.4 No By–product of drinking water disinfection Chloramines (ppm) 2017 MRDL = 4 MRDLG = 4 3.04 1.6 – 4.24 No Water additive used to control microbes Chlorine (ppm) 2017 MRDL = 4 MRDLG = 4 2.05 0.76 – 2.87 No Water additive used to control microbes E. coli (# positive samples) 2017 see footnote #1 0 0 NA No Human and animal fecal waste Fluoride (ppm) 2017 4 4 average = 0.4 ND – 0.8 No Erosion of natural deposits; Water additive that promotes strong teeth; Discharge from fertilizer and aluminum factories Haloacetic Acides (HAAs) (ppb) 2017 60 NA 21.8 (Maximum LRAA) 3.3 – 25 (individual sample sites) No By–product of drinking water disinfection TTHMs (Total Trihalomethanes) (ppb) 2017 80 NA 49.0 (Maximum LRAA) 26 – 77 (individual sample sites) No By–product of drinking water disinfection Total Coliform Bacteria (% positive samples) 2017 5% 0% 0.78% 0 – 0.78% No Naturally present in the environment Total Organic Carbon (TOC) 2 (removal ratio) 2017 TT NA 1.53 (running annual ave.) 1.08 – 1.87 (range of monthly) No Naturally present in the environment Turbidity 3 (NTU) 2017 TT=1 NTU and 95% of samples <0.3 NTU NA 0.17 NTU and 100% of samples <0.3 NTU 0.03 – 0.17 No Soil Runoff Gross Beta (pCi/L) 2017 50 0 4.2 NA No Decay of natural and man–made deposits TAP WATER SAMPLES WERE COLLECTED FOR LEAD AND COPPER ANALYSES FROM SAMPLE SITES THROUGHOUT COMMUNITY 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) 2015 1.3 1.3 0.123 0/60 No Corrosion of household plumbing systems; Erosion of natural deposits Lead (ppb) 2015 15 0 <3 1/60 No Corrosion of household plumbing systems; Erosion of natural deposits UNREGULATED SUBSTANCES SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED AMOUNT DETECTED RANGE DETECTED VIOLATION TYPICAL SOURCE Bromodichloromethane (ppb) 2017 22 NA No By-product of drinking water disinfection Bromoform (ppb) 2017 1.8 NA No By-product of drinking water disinfection Chlorodibromomethane (ppb) 2017 12 NA No By-product of drinking water disinfection Chloroform (ppb) 2017 25 NA No By-product of drinking water disinfection Sodium (ppm) 2017 35 32.7 – 37.2 No Naturally occurring Sulfate (ppm) 2017 42 38 - 46 No Runoff/leaching from natural deposits; Industrial wastes 1 Routine and repeat samples are total coliform- positive and either is E. coli-positive or system fails to take repeat samples following E. coli-positive routing sample or system fails to analyze total coliform- positive repeat sample for E. coli. 2 Depending on the TOC in our source water, the system MUST have a certain percent (%) removal of TOC or must achieve alternative compliance criteria. If we do not achieve that percent removal, there is an alternative percent removal. If we fail to meet the alternative percent removal, we are in violation of a Treatment Technique. 3 Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of the effectiveness of our filtration system. The turbidity rule requires that 95% or more of the monthly samples must be less than or equal to 0.3 NTU. 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, 2017. 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.