PFAS Testing and Assistance Program (PFAS TAP)

Private wells are not protected under the Environmental Protection Agency’s (EPA) Safe Drinking Water Act (SDWA). It is the responsibility of the well user to test their drinking water for contaminants. In 2024, the Colorado Department of Public Health and Environment (CDPHE) launched the PFAS Testing and Assistance Program to provide resources for private well users. PFAS are a large group of human-made chemicals that exist throughout our environment and are associated with certain negative health effects.

PFAS TAP offers free PFAS testing to private well users and free water filters that remove PFAS and other common well contaminants to income-eligible households with PFAS concentrations over the EPA’s maximum contaminant levels (MCLs). MCLs are enforceable levels for contaminants in drinking water that must be met by public water systems. MCLs can also be used to help private well users evaluate their risk of exposure to contaminants. Testing helps us identify and minimize exposure to PFAS in the area and develop recommendations on PFAS contamination. This program is available while supplies last.

Testing process:

• The company providing the tests, Cyclopure, will mail you a sampling test kit.
• Follow the directions included with the sampling test kit.
• Cyclopure will send a letter with your results approximately two weeks after testing.

For help interpreting lab results, visit our well-water tool. You can also contact PFAS TAP staff at cdphe_pfas-tap@state.co.us or 303-906-8052.

• Filters meet NSF standards to reduce PFAS levels by >99%. Reducing exposure to PFAS reduces the risk of potential health impacts.
• In addition to removing PFAS, these filters also remove several other common well-water contaminants such as heavy metals, E.coli/bacteria, and nitrates.
• Used filters can be returned to the manufacturer for recycling.
• You’ll receive an automated reminder for changing the filter.
• Using a pitcher filter for your drinking water reduces exposure to PFAS and other contaminants but does not require costly changes to household plumbing.
• Please note: These filters will remove naturally occurring fluoride. Talk to your dentist about ways to get fluoride to protect oral health.

Please refer to the manufacturer’s website for additional information about the filter’s capabilities.

Colorado households that meet the following criteria:

1. The amount of PFOS and/or PFOA in your well is higher than 4 ppt (parts per trillion, this is the same as ng/L).

   If you tested your well independently (e.g., not through PFAS TAP), you can receive a free water filter if you submit valid PFOS or PFOA results higher than 4 ppt. Results must be shown by a lab report or other official documentation.

2. Your household income is at or below 80% of the median income for your county.

   Your income will be verified using your most recent completed tax return.

Households that do not qualify for a free filter will receive a discount code to buy the filter system at a 30% discount. If you participated in PFAS TAP, your results letter will include a discount code. Learn more about the filter system provided by PFAS TAP.

We don’t know whether your existing filter will remove PFAS because different filters remove different contaminants.

• The Water Quality Association (WQA) maintains a list of products that are certified to remove various contaminants from drinking water.
  • You can search through the products and check if your filter is certified via the Water Quality Association’s Certified Drinking Water Unit search tool.
• If you want to shop for a new filter, look for manufacturers that have demonstrated the water filter can remove PFAS to non-detectable levels and meet NSF standards to reduce PFAS by >99%. Reverse osmosis and granular activated carbon filters can remove PFAS as long as you follow filter maintenance guidelines.
• Consult with a water quality professional to ensure your drinking water filtration system is appropriate for the contaminants and quality of your water.

Current research shows that PFAS do not easily enter the body through the skin. For many people, exposure to PFAS in drinking water is the most significant way PFAS can end up in their bodies.

If drinking water has PFAS, we recommend following the guidelines in the chart below to reduce exposure:

Learn more about reducing your exposure to PFAS in drinking water by using at-home water filtration.

Based on current research, most PFAS do not easily enter the body through the skin, so filtration is recommended for water used for cooking and drinking.

• PFAS TAP currently provides point-of-use (POU) filters (i.e., countertop pitchers or faucet filters) to eligible households, which can be a cost-effective way to reduce PFAS in water used for drinking and cooking. Because pitcher filters only filter the water intended for consumption, pitchers may help save money and reduce waste. However, pitcher filters may require frequent refills in households that consume a lot of water.
• Whole-house filtration systems are another option, but they can be expensive and may increase overall water use. PFAS TAP does not provide whole-house filtration systems. Households can explore different filtration options based on their needs.

The Washington State Department of Health provides some other resources, such as a POU filter factsheet and home water treatment factsheet, on their webpage.

Learn more about reducing your exposure to PFAS in drinking water by using at-home water filtration.

PFAS TAP partners with local public health agencies and community organizations to perform targeted outreach for PFAS TAP in counties with the highest need for testing and filtration resources.

• CDPHE provides all funding, testing, and filtration materials and maintains all daily operations for PFAS TAP.
• CDPHE can enter into a small number of county partnerships each year based on the needs of the community and CDPHE, and the county partner’s capacity. When a county partnership is utilized, the county partner’s role is to help CDPHE promote PFAS TAP throughout the county and support logistics for outreach events.

If your agency or organization is interested in forming a county partnership with PFAS TAP, please contact us about opportunities for future collaboration!

On April 10, 2024, the EPA finalized Maximum Contaminant Levels (MCLs) establishing legally enforceable regulations for six PFAS. MCLs are standards that must be met by public water systems. MCLs account for health information, available testing technology, treatment techniques, and costs. Table 1 below shows the five individual PFAS and one PFAS mixture that have MCLs.

If you would like to learn more about the regulations for PFAS, the EPA also provided resources, like this summary of the PFAS National Primary Drinking Water Regulation or the questions and answers PFAS and Drinking Water Regulation factsheet. You can also view the EPA's Final PFAS National Primary Drinking Water Regulation information.

PFAS with individual MCLs

As shown above, five PFAS (PFOA, PFOS, PFHxS, PFNA, and GenX) are regulated as separate contaminants with individual MCLs.

• For example, if the PFOA level in drinking water is 4.1 ng/ L, it is above the MCL for PFOA of 4.0 ng/L. This means that public water systems are required to take action to lower PFAS levels.
• Private wells are not regulated by the MCLs mandated in the Safe Drinking Water Act. If the PFAS levels are above the MCLs for one or more PFAS, we recommend reducing exposure by using at-home water filters or an alternate source of water for drinking and cooking.

PFAS Mixture

Another type of PFAS, PFBS, is regulated as part of a mixture. The mixture calculation includes PFBS and three other PFAS (PFNA, PFHxS, and GenX). Following EPA guidance, CDPHE uses a hazard index to look at the health risks of exposure to this PFAS mixture. The threshold for the PFAS hazard index is 1. You can use our private well tool to calculate the hazard index from your drinking water results.

• A hazard index below 1 means exposure to the mixture of PFAS is not expected to increase the risk of health effects.
• A hazard index above 1 means exposure to a mixture of PFAS has the potential to increase the risk of health effects.
• For example, if the hazard index from the combined levels of PFNA, PFHxS, GenX, and PFBS in drinking water is 0.2, then the levels are below the mixture MCL. This means results are below the hazard index of 1 and are not expected to increase the risk of adverse health effects.
• Private wells are not regulated like public water systems. If the PFAS levels are above any of the MCLs, including the hazard index, we recommend reducing exposure by using at-home water filters or an alternate source of water for drinking and cooking.

If you would like to see the example calculation of the hazard index from the EPA, view the Understanding the PFAS Hazard Index factsheet.

PFAS have been extensively used in consumer and industrial products since the 1950s. The chemicals can migrate into the soil, water, and air. PFAS can come from many sources, and we often don’t have enough information to determine the specific source or sources. Sampling from PFAS TAP will improve our understanding of potential sources and allow for more targeted recommendations to residents on testing and treatment of PFAS.