PFAS
The City of Sugar Land is committed to providing its residents with clean, safe drinking water. The drinking water meets all current health and safety guidelines set by the Environmental Protection Agency (EPA) and the Texas Commission on Environmental Quality (TCEQ). The EPA sets these guidelines, called the National Primary Drinking Water Regulations, as part of its authority under the Safe Drinking Water Act. The list of drinking water contaminants regulated by the EPA and TCEQ evolves over time as rigorous scientific research reveals new concerns.
As part of that process, the EPA finalized the first National Primary Drinking Water Regulations for six per- and polyfluoroalkyl substances (PFAS) in April 2024. The new regulation establishes legally enforceable limits for several PFAS compounds in drinking water. Under the new rule, water systems will be required to conduct initial monitoring for six PFAS before 2027, followed by ongoing compliance monitoring. In 2029, water systems which violate one or more of these limits must take action to reduce levels of these PFAS in their drinking water and must provide notification to the public of the violation.
The city’s water systems monitored for PFAS contaminants under the EPA’s Fifth Unregulated Contaminant Monitoring Rule (UCMR5) between February 2023 and February 2024. Results showed no detections of PFAS in the drinking water in the Greatwood, New Territory, or RiverPark water systems. The City Main water system results showed detections for eight different PFAS compounds. Based on results of the city’s UCMR5 monitoring, Sugar Land’s water systems would be in compliance with the new PFAS MCLs taking effect in 2029.
Data gathered under UCMR5 monitoring will assist staff in identifying potential sources of PFAS and evaluating treatment strategies for removing PFAS. Staff will use the results of this monitoring to help determine whether changes to the City’s water treatment processes are needed to continue to protect public health.
What are PFAS?
PFAS are a diverse group of thousands of man-made chemicals used in a wide range of consumer and industrial products since the 1940’s due to their resistance to grease, oil, water, and heat. These qualities allowed them to be applied to nearly any material, to make them water, oil, and stain resistant. PFAS are used in fabrics, carpeting, non-stick pans, cleaning products, paints, personal care products, food-packaging, fire-fighting foams, and other products. While some PFAS have been phased out in the US, they may still be used in imported products, and US manufacturers continue to make and use other PFAS in their place.
Commonly referred to as “forever chemicals,” PFAS do not easily break down. Studies have shown some types of PFAS accumulate in the environment and in the bodies of fish, animals, and humans. The widespread use of PFAS and their ability to remain in the environment means that PFAS levels from past and current uses can result in increasing levels of environmental contamination over time.
PFAS Regulations
The EPA and TCEQ have not had drinking water regulations for PFAS in the past. The new rule establishes Maximum Contaminant Levels (MCLs) for five individual PFAS chemicals: PFOA, PFOS, PFNA, PFHxS, and GenX Chemicals. It also sets a limit for mixtures of any two or more of four PFAS (PFNA, PFHxS, PFBS, and GenX Chemicals) using a Hazard Index MCL of 1.0 to account for the combined and co-occurring levels of these PFAS in drinking water. A Hazard Index is an equation reached by combining information from measurements of the four chemicals. The table below shows the EPA's new MCLs for PFAS substances in parts per trillion (ppt), as well as the Hazard Index for a combination of two or more of four PFAS chemicals.
| Chemical | MCL |
|---|---|
| PFOA | 4.0 ppt |
| PFOS | 4.0 ppt |
| PFNA | 10 ppt |
| PFHxS | 10 ppt |
| HFPO-DA (GenX) | 10 ppt |
| Mixture of two or more: PFHxS, PFNA, PFBS, and GenX | Hazard Index of 1 |
Under the new rule, water systems will be required to conduct initial monitoring for these six PFAS before 2027, followed by ongoing compliance monitoring. Water systems must also provide the public with information on the levels of these PFAS in their drinking water beginning in 2027. Where PFAS is found at levels that exceed the MCLs, systems must implement solutions to reduce PFAS in their drinking water before 2029. Beginning in 2029, water systems which violate one or more of these MCLs must take action to reduce levels of these PFAS in their drinking water and must provide notification to the public of the violation.
Compliance for the new PFAS MCLs is based on a running annual average of results at each sample location, not on individual sample results. The running annual average is the average of sample results taken at a particular monitoring location over the previous four calendar quarters. A single high sample will not necessarily put the system in violation, as long as the running annual average is below the MCL. A system is in compliance if their running annual average is less than or equal to the MCLs for all regulated PFAS.
Sugar Land and PFAS
The city’s water systems monitored for PFAS contaminants under the EPA’s Fifth Unregulated Contaminant Monitoring Rule (UCMR5) between February 2023 and February 2024. Samples were collected from all the city’s water treatment plants to monitor for 29 PFAS contaminants to assist the EPA in gathering data on the nationwide occurrence of PFAS in drinking water. Two rounds of samples were collected from plants treating only groundwater, and four rounds were collected from plants that receive or treat surface water.
Results showed no detections of PFAS in the drinking water in the Greatwood, New Territory, or RiverPark water systems.
The table below summarizes the PFAS compounds that were detected in Sugar Land’s Main water system. Results are shown in parts per trillion (ppt). One part per trillion is equal to:
- One drop of water in 20 Olympic-sized swimming pools
- One cent out of $10 billion
- One second in approximately 32,000 years
| Compounds Detected in the Main Water System | Average Level Detected |
Range of Detects |
Unit of Measure |
|---|---|---|---|
| 4,8-dioxa-3H-perfluorononanoic acid (ADONA) | 0.3 | 0 - 3.4 | ppt |
| Perfluorobutanoic acid (PFBA) | 8.8 | 0 - 74.8 | ppt |
| Perfluorobutanesulfonic acid (PFBS)* | 1.1 | 0 - 5.8 | ppt |
| perfluoroheptanoic acid (PFHpA) | 0.3 | 0 - 3.6 | ppt |
| Perfluorohexanoic acid (PFHxA) | 2.1 | 0 - 12.9 | ppt |
| perfluorooctanoic acid (PFOA)* | 0.3 | 0 - 4.1 | ppt |
| Perfluoropentanoic Acid (PFPeA) | 65.9 | 0 - 358 | ppt |
| 1H,1H, 2H, 2H-perfluorooctane sulfonic acid (6:2FTS) | 55.2 | 0 - 672 | ppt |
Results showed detections in the Main water system for eight different PFAS compounds, two of which will be regulated under the new rule, PFOA and PFBS. PFOA was detected in the fourth quarter samples at two entry points in the Main system, with results being 4.0 ppt and 4.1 ppt. All other samples for PFOA were non-detected. Although one of the samples was detected above the MCL of 4.0 ppt, the system would not be in violation of the MCL as compliance is based on the running annual average at each sample location. The running annual average at that location would be 1.03 ppt for PFOA (below the MCL of 4.0).
PFBS was detected in the third and fourth quarter samples at three entry points in the Main system. Under the new rule, there is not an individual MCL for PFBS. PFNA, PFHxS, or GenX Chemicals would also need to be present in the samples with PFBS for the Hazard Index MCL to apply. These three compounds were non-detected in all samples.
All results from the city’s UCMR5 monitoring can be found here.
Based on results of the city’s UCMR5 monitoring, Sugar Land’s water systems would be in compliance with the new PFAS MCLs taking effect in 2029. Data gathered under UCMR5 monitoring will assist staff in identifying potential sources of PFAS and evaluating treatment strategies for removing PFAS. Staff will use the results of this monitoring to help determine whether changes to the City’s water treatment processes are needed to continue to protect public health.
Where Can I Find Additional Information on PFAS?
Additional information on PFAS and the new drinking water regulation can be found on the EPA’s website at Per- and Polyfluoroalkyl Substances (PFAS) | US EPA.