2020 Water Utilities Consumer Confidence Report 2020 Water Utilities Consumer Confidence Report | Page 3

Contaminants may be found in drinking water that could cause taste , color , or odor problems but are not necessarily causes for health concerns . For more information , please call Laboratory Services at 817-575-8984 .

Chloride ppm 16.0 13.0 25 Magnesium ppm 4.21 3.67 6.09 pH pH units 7.78 7.29 8.56 Potassium ppm 4.29 3.98 4.60 Sodium ppm 22.2 17.6 31.8 Sulfate ppm 37.9 32.9 54.3 Alkalinity , Total ppm 82.2 61.4 114

Total Dissolved Solids

Hardness , Total ( as CaC03 ) ppm 165 114 246

ppm grains / gal

103 6.0

70 4.1

159 9.3

Table B . 2020 Unregulated Contaminants . Unregulated contaminants are those for which EPA has not established drinking water standards . The purpose of unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted .

By-product of drinking water disinfection ; not regulated individually ; included in Haloacetic Acids .

Substances Expected to be in Drinking Water

The City of Arlington and the State of Texas both analyze your drinking water . Any regulated substances that were detected during the last year are shown in Table A , and all are well below the established maximum contaminant levels . All water dissolves substances from the ground as it flows over and through it . Substances that may be present in raw water include :

Microbes such as viruses and bacteria that come from septic systems , agricultural livestock operations and wildlife

Salts and metals that can be naturally occurring or the result of urban storm water runoff , industrial or domestic wastewater discharges or farming

Pesticides and herbicides that may come from a variety of sources such as agriculture , urban storm water runoff or residential uses

Radioactive substances that are naturally occurring

Organic chemical substances including synthetic and volatile organic chemicals that are by-products of industrial processes and can also come from gas stations and urban stormwater runoff

Arlington Water Utilities Lab Staff Spotlight 11 FT and PT staff | 152 years of laboratory experience TCEQ Licenses : 2 A , 3 B , 1 C and 3 D | Degrees : 3 Masters and 7 Bachelors

Unregulated Contaminants - UCMR 4 Monitoring . Although not currently regulated by the EPA , the City of Arlington has been collecting data for the EPA regarding the occurrence of these compounds in our water supply , which is the first step in determining whether they should be regulated . These samples were collected in 2019 and 2020 . Arlington detected only four of the 30 compounds being monitored .

Substance Units Avg . Min . Max . Possible Source

HAA5 ppb 5.43 2.70 8.57 HAA6Br ppb 5.59 3.48 9.09 HAA9 ppb 9.20 4.99 14.56

By-product of drinking water disinfection .

Manganese ppb 2.27 0.46 5.10 Naturally present in the environment

To help advance the science of drinking water , Arlington Water Utilities collected data for the Unregulated Contaminant Monitoring Rule ( UCMR ), which provides EPA and other interested parties with scientifically valid data on the occurrence of contaminants in source water and drinking water . This is the first step to determine whether certain compounds should be regulated . In 2019-2020 , data was collected for Manganese , Bromide , Total Organic Carbon and three Haloacetic Acid groups .

Refer to Table B ( above ) for details on specific detections . The presence of a compound does not necessarily equate to a health risk . The concentration of a compound is a far more important factor in determining whether there are health implications . To learn more about the Unregulated Contaminant Monitoring Rule , visit : www . epa . gov / dwucmr or www . DrinkTap . org .