Understanding Emerging Compounds Helps Us Keep Your Water Clean and Safe

DC Water and approximately 6,000 other water utilities in the country monitor for unregulated compounds in accordance with EPA's fourth Unregulated Contaminant Monitoring Rule (UCMR4). This information will help EPA determine if regulation is necessary to protect public health, and it will help DC Water and other public water systems determine how to address the issue of emerging compounds. 

Learn more about UCMR4 here

*Minimum Reporting Levels (MRLs) are derived from the capability of the anayltical method. Learn more about EPA's process here. 

*Reference Concentrations are health-based levels above which adverse health effects have been documented. They are not regulations, and not all contaminants have reference concentrations. Learn more about EPA's process here

*One microgram per Liter (µg/L) (or 1 part per billion) is the equivalent of a few drops of water in an Olympic-sized swimming pool.

 

As standard procedure, the UCMR4 testing results are currently being reviewed by EPA Region III. When the data is approved, it will be posted here.

UCMR3

DC Water and approximately 6,000 other water utilities in the country monitored for unregulated compounds in accordance with EPA's third Unregulated Contaminant Monitoring Rule (UCMR3). To comply with the UCMR3, DC Water conducted these tests quarterly in 2014. The results of all testing conducted by water utilities isposted on EPA's UCMR website.

Detected Unregulated Compounds (parts per billion)

Compound Date Sampled Dalecarlia Water Treatment Plant Entry Point Distribution System Sample 1 (Dalecarlia) McMillan Water Treatment Plant Entry Point Distribution System Sample 2 (McMillan) Common Sources
Chlorate January 2014 210 200 160 160 Byproduct of the water disinfection process and ingredient in herbicides and explosives.
April 2014 140 170 120 120
July 2014 430 470 250 250
October 2014 330 340 410 410
Chromium July 2014 0.20 No Detection 0.24 No Detection Naturally ocurring element that can be found in soils, plants, rocks, water and animals.
October 2014 0.26 0.31 0.36 0.32
Chromium - 6 January 2014 0.091 0.077 0.082 0.074 Ingredient in some paint and industrial products, such as metal coatings.
April 2014 0.092 0.12 0.075 0.077
July 2014 0.098 0.10 0.10 0.10
October 2014 0.063 0.076 0.077 0.079
Molybdenum October 2014 1.0 1.1 1.2 1.2 Naturally-occurring metal that can be found in rocks and soil. It is also present in plants, animals and bacteria. Molybdenum is most commonly used in the production of structural steel, stainless steel, cast iron and other alloys.
Strontium January 2014 160 140 130 120 Occurs naturally in the environment but can be released at higher levels from industrial processes, such as coal burning and fertilizer manufacturing.
April 2014 130 120 120 120
July 2014 24 210 200 190
October 2014 220 230 260 260
Vanadium April 2014 0.22 0.20 No Detection No Detection Occurs naturally in many minerals and fossil fuel deposits. The primary industrial use is strengthening steel.
July 2014 1.3 0.85 0.57 0.55
October 2014 0.60 0.57 0.40 0.39

 

 

Compound Date Sampled Dalecarlia Water Treatment Plant Entry Point McMillan Water Treatment Plant Entry Point Common Sources
perfluorooctanesulfonic (PFOS) January 2014 No Detection No Detection Surfactant or emulsifier; used in fire-fighting foam, circuit board etching acids, alkaline cleaners, floor polish, and as a pesticide active ingredient for insect bait traps. U.S. manufacture of PFOS phased out in 2002, however, PFOS are still generated incidentally.
April 2014 No Detection No Detection
July 2014 No Detection No Detection
October 2014 No Detection  No Detection
perfluorooctanoic acid (PFOA) January 2014 No Detection No Detection Perfluorinated aliphatic carboxylic acid; used for its emulsifier and surfactant properties in or as fluoropolymers (such as Teflon),
fire-fighting foams, cleaners, cosmetics, greases and lubricants, paints, polishes, adhesives and photographic films.
April 2014 No Detection No Detection
July 2014 No Detection No Detection 
October 2014 No Detection No Detection
perfluorononanoic acid (PFNA) January 2014 No Detection No Detection Manmade chemical; used in products to make them stain, grease, heat and water resistant.
April 2014 No Detection No Detection
July 2014 No Detection No Detection
October 2014 No Detection No Detection
perfluorohexanesulfonic acid (PFHxS) January 2014 No Detection No Detection Manmade chemical; used in products to make them stain, grease, heat and water resistant.
April 2014 No Detection No Detection
July 2014 No Detection No Detection
October 2014 No Detection  No Detection
perfluoroheptanoic acid (PFHpA) January 2014 No Detection No Detection Manmade chemical; used in products to make them stain, grease, heat and water resistant.
April 2014 No Detection  No Detection
July 2014 No Detection No Detection
October 2014 No Detection No Detection
perfluorobutanesulfonic acid (PFBS) January 2014 No Detection No Detection Manmade chemical; used in products to make them stain, grease, heat and water resistant.
April 2014 No Detection No Detection
July 2014 No Detection No Detection
October 2014 No Detection  No Detection