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Water Testing Results D uring 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, 2016. 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 MCL [MRDL] MCLG [MRDLG] AMOUNT DETECTED RANGE LOW-HIGH VIOLATION TYPICAL SOURCE Bromate (ppb) 2016 10 0 2.7 ND–6.9 No By-product of drinking water disinfection Chloramines (ppm) 2016 [4] [4] 2.86 1.40–3.99 No Water additive used to control microbes Chlorine (ppm) 2016 [4] [4] 1.51 0.83–2.86 No Water additive used to control microbes E. coli (# positive samples) 2016 see footnote #1 0 0 NA No Human and animal fecal waste Fluoride (ppm) 2016 4 4 0.75 NA No Erosion of natural deposits; Water additive which promotes strong teeth; Discharge from fertilizer and aluminum factories Haloacetic Acids [HAA] (ppb) 2016 60 NA 25.3 13–31 No By-product of drinking water disinfection TTHMs [Total Trihalomethanes] (ppb) 2016 80 NA 42.5 30–63 No By-product of drinking water disinfection Total Coliform Bacteria (% positive samples) 2016 TT NA 0.78 NA No Naturally present in the environment Total Organic Carbon [TOC] 2 (removal ratio) 2016 TT NA 1.46 1.22–1.89 No Naturally present in the environment Turbidity 3 (NTU) 2016 TT = 1 NTU NA 0.16 0.03–0.16 No Soil runoff Turbidity (Lowest monthly percent of samples meeting limit) 2016 TT = 95% of samples meet the limit NA 100 NA No Soil runoff Tap water samples were collected for lead and copper analyses from sample sites throughout the community SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED AL MCLG AMOUNT DETECTED (90TH%TILE) 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 ND 1/60 No Corrosion of household plumbing systems; Erosion of natural deposits UNREGULATED SUBSTANCES 4 SUBSTANCE (UNIT OF MEASURE) YEAR SAMPLED AMOUNT DETECTED RANGE LOW-HIGH TYPICAL SOURCE Bromodichloromethane (ppb) 2016 16 NA By-product of drinking water disinfection Bromoform (ppb) 2016 0.68 NA By-product of drinking water disinfection Chlorodibromomethane (ppb) 2016 8.3 NA By-product of drinking water disinfection Chloroform (ppb) 2016 23 NA By-product of drinking water disinfection Sodium (ppm) 2016 32.2 NA NA Sulfate (ppm) 2016 32 NA Runoff/leaching from natural deposits 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 routine 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. 4 Unregulated contaminants are those for which U.S. EPA has not established drinking water standards. The purpose of unregulated contaminant monitoring is to assist U.S. EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulations are warranted.