Sampling Results

During the past year, we have taken hundreds of water samples in order to determine the presence of any radioactive, biological, inorganic, volatile organic or synthetic organic contaminants. The tables below show only those contaminants that were detected in the water. The state requires us to monitor for certain substances less often than once per year because the concentrations of these substances do not change frequently. In these cases, the most recent sample date are included, along with the year in which the sample was taken.
REGULATED SUBSTANCE               
Substance (Unit of Measure) Year Sampled MCL [MRDL] MCLG [MRDLG] Amount Detected Range Low-High Violation Typical Source
Alpha Emitters (pCi/L) 2012 15 0 11 0-11 no Erosion of natural deposits 
Arsenic (ppb) 2013 10 0 11 1.7-2.6 No Erosion of natural deposits; runoff from glass and electronics production wastes
Barium (ppm) 2013 2 2 0.064 0.028-0.064 No Discharge of drilling wastes; Discharge from metal refineries; Erosion of natural deposits
Chromium (ppb) 2013 100 100 6.6 2.2-6.6 No Discharge from steel and pulp mills; Erosion of natural deposits
Fluoride (ppm) 2013 4 4 0.55 0.29-0.55 No Erosion of natural deposits; Water additive that promotes strong teeth; Discharge from fertilizer and aluminum factories
Haloacetic Acids [HAAs] Stage 1 (ppb) 2014 60 NA 6 3.5-16 No By-product of drinking water disinfection 
Nitrate (ppm) 2014 10 10 3.6 2.7-3.6 No Runoff from fertilizer use; Leaching from septic tanks, sewage; Erosion of natural deposits 
Selenium (ppb) 2013 50 50 12 6-12 No Discharge from petroleum and metal refineries; Erosion of natural deposits; Discharge from mines
TTHMs {Total Trilhalomethanes]- Stage 1 (ppb) 2014 80 NA 0.014 0.002-0.023 No By-product of drinking water disinfection 
Uranium (ppb) 2012 30 0 8.4 0-8.4 No Erosion of natural deposits
Tap water samples were collected for lead and cooper 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 
Cooper (ppm) 2013 1.3 1.3 0.11 0/30 No Corrosion of household plumbing systems; Erosion of natural deposits
Lead (ppb) 2016 15 0 1.2 0/30 No  Corrosion of household plumbing systems; Erosion of natural deposits
SECONDARY SUBSTANCE               
Substance (Unit of Measure) Year Sampled SMCL MCLG Amount detected Range Low-High Violation Typical Source
Alkalinity Total (ppm) 2013 300 NA 177 154-177 No NA
Calcium (ppm) 2013 200 NA 66 42-66 No NA
Chloride (ppm) 2013 250 NA 22 11-22 No Runoff/leaching from natural deposits
Conductivity (uS/cum) 2013 1,500 NA 690 520-690 No Substance that form ions when in water
Corrosivity (Units) 2013 Noncorrosive NA 0.51 0.14-0.51 No Natural or industrially influenced balance of hydrogen carbon and oxygen in the water; Affected by temperature and other factors.
Gross Uranium By Activity (pCi/L) 2013 30 0 9.8 0-9.8 No Erosion of natural deposits
Hardness, Total [as CaCO3] (ppm) 2013 400 NA 290 190-290 No Naturally occuring
Iron (ppb) 2013 300 NA 2 0.012-2 No Leaching from natural deposits; Industrial wastes
Magnesium (ppm) 2013 150 NA 30 20-30 No Naturally occuring
Manganese (ppb) 2013 50 NA 0.02 0.0086-0.02 No Leaching from natural deposits
Nickel (ppb) 2013 100 NA 0.0026 0-0.0026 No Naturally occurring 
pH (Units) 2013 6.5-8.5 NA 8.2 7.8-8.2 No Naturally occurring
Potassium (ppm) 2013 100 NA 4.2 7.8-8.2 No Naturally occurring; Found in water softeners 
Silica (ppm) 2013 50 NA 32 27-32 No Naturally occurring as sand, quartz, sandstone and granite 
Sodium (ppm) 2013 100 NA 39 21-39 No Naturally occurring; Component of water softeners
Sulfate (ppm) 203 250 NA 160 60-160 No Runoff/leaching from natural deposits; Industrial wastes
Total Dissolved Solids [TDS] (ppm)  2013 500 NA 450 320-450 No Runoff/leaching from natural deposits
Zinc (ppm) 2013 5 NA 0.04 0.0072-0.04 No Runoff/leaching from natural deposits; Industrial wastes
Definitions
  • AL (Action Level): The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow. 
  • uS/cm (microsiemens per centimeter): A unit expressing the amount of electrical conductivity of a solution.
  • MCL (Maximum Contaminant Level): The highest level of contaminant that is allowed in drinking water. MCLs are set as close to the MCLs are set as close to the MCLGs as feasible using the best available treatment technology.
  • MCLG (Maximum Contaminant Goal): The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety. 
  • MRDL (Maximum Residual Disinfectant Level): The highest level of a disinfectant allowed in drinking water. There is a convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants. 
  • MRDLG(Maximum Residual Disinfectant Level): The level of a drinking water disinfectant below which there is a no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants. 
  • NA: Not applicable 
  • pCi/L (picocuries per liter): A measure of radioactivity 
  • ppb (parts per billion): One part substance per billion parts water (or micrograms per liter). 
  • ppm (parts per million): One part substance per million parts water (or milligrams per liter).
  • SMCL (Secondary Maximum Contaminant Level): SMCLs are established to regulate the aesthetics of drinking water like taste and odor.