EPA Issues New List of Water Contaminants

Posted on 8/16/2021 by Roseanne Bottone

US EPA released a draft of its fifth Contaminant Candidate List (CCL 5) in July 2021.
The CCL is a list of contaminants found in public water systems that are not already subject to drinking water regulations. The Safe Drinking Water Act (SDWA) requires EPA to update the CCL every five years.

EPA’s Draft CCL 5

EPA's Draft CCL includes: 
  • 66 individual chemicals, 
  • 12 microbes, and 
  • 3 chemical groups— 
    • Per- and Polyflouralkyl substances (PFAS), 
    • cyanotoxins, and 
    • disinfection byproducts (DBPs). 
EPA will accept public comments on the Draft CCL 5 until September 17, 2021 and will consult with the Science Advisory Board (SAB) this Fall. A Final CCL 5 is expected in July 2022.
Adding a chemical to the CCL does not subject the chemical to any regulations and does not necessarily mean that the chemical will be regulated in the future.  It serves as a heads-up to public water systems that EPA may create regulations for these contaminants in the future.
Identify the major US EPA water regulations that impact your site’s activities with the self-paced Clean Water Act & Safe Drinking Water Act Regulations online course.

PFAS in Drinking Water

PFAS are proposed as a group—except for perfluorooctanoic acid (PFOA), also known as C8, and perfluorooctane sulfonate (PFOS).
PFOAs and PFOSs are the two PFAS chemicals that the US has produced the most of. PFOA and PFOS are not included in the Draft CCL 5 because the EPA is already moving forward with national primary drinking water MCL standards for these two contaminants. 
In July 2021, a bill that aims to limit the use of PFAS chemicals and remediate existing environmental contamination passed the US House of Representatives under the name PFAS Action Act of 2021.   

What Happens Next?

The law requires EPA to make a “regulatory determination”—an official decision to regulate or not regulate a contaminant—for at least five substances on each CCL update.

The SDWA sets three criteria for determining if a contaminant should be regulated:
  1. Might the contaminant have an adverse effect on human health?
  2. Is the contaminant known to occur (or is there a substantial likelihood it will occur) in public water systems at a frequency and level of public health concern?
  3. Does regulation of the pollutant present a meaningful opportunity for the reduction of health risks for people serviced by public water systems?
When EPA decides that drinking water regulations are warranted for a specific contaminant, the agency creates a Maximum Contamination Level or MCL. An MCL is the maximum concentration of a contaminant that can be present in drinking water and have that water still be deemed “fit for human consumption.”

See a list of current MCLs enforced by EPA here.

Recent Regulatory Determinations for CCL 4

The fourth CCL was released in 2016. In February 2021, EPA reissued regulatory determinations for eight of the contaminants on CCL 4, including PFOA and PFOS.

Online Training for New Environmental Managers  

The Complete Environmental Regulations online course guides you through EPA’s major programs—from the Clean Air and Clean Water Acts to EPCRA, CERCLA/Superfund, TSCA, and more. Build knowledge and skills to find, interpret, and apply the EPA rules that you need to know to keep your site in compliance and avoid costly civil penalties (as high as $100,000 per day, per violation!)
Along the way, we cover the keys to applicability for each program, so you can identify which environmental regulations impact your facility, and take the steps needed to achieve compliance.

Tags: Clean Water Act, drinking water, environmental compliance, SDWA

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