Known as “forever chemicals” because they do not break down naturally, a presentation on PFAs (perflouroalkyl and polyflouroalkyl susbstances) and the EPА requirements of the National Primary Drinking Water Regulation Rule was made by representatives of the Trinity River Authority (TRA) during the March 10 regular meeting of the Livingston City Council.
Most exposure to PFAs comes from consumer goods and not drinking water. In fact, the EPA set a maximum contaminant level for PFAs of four parts per trillion. For perspective, four parts per trillion is the same as putting one drop of PFAs into the equivalent of 20 Olympic-sized swimming pools.
Accompanied by Douglas D. Haude and Billy Lewis, Thresa Aguayo made the presentation.
She reported that the Livingston Regional Water Supply System (LRWSS) is a surface water plant with a raw water intake located on Lake Livingston. The City of Livingston is LRWSS’s only customer, as TRA provides the city with 100% of its drinking water. TRA wholesales potable water to the City of Livingston, which then distributes water to its customers, including the Texas Department of Criminal Justice Polunsky Unit and the IAH Secure Adult Detention Facility.
The system was originally sized at 2.0 million gallons per day (MGD), was expanded to 3.0 MGD in 1992 and currently has a maximum capacity of 7.0 MGD. It serves approximately 13,000 people. Designed to meet the growing municipal and industrial water needs of the area, utilizing water from Lake Livingston, the system underwent a major expansion in 2017, which included a new raw-water pump station, new pipelines, chemical feed systems, and a new control building.
PFAS are a group of thousands of manmade chemicals that are used in various products and are known for their persistence in the environment and potential health risks.
Aguayo said PFAs do not occur naturally and first appeared in the 1940s as non-stick coatings. Over 12,000 have been identified currently in a wide range of products including candy wrappers, fast food packaging, pesticides, stain-resistant products, firefighting foams, microwave popcorn bags, shampoo, water-resistant clothing, non-stick cookware, dental floss, nail polish, cleaning products, cosmetics, plaints sealants and varnishes, among other things.
Products containing PFAs are used, ingested, inhaled or absorbed through the skin. They are detected in 99% of the population’s blood and are linked to many different health concerns, including cancer.
PFAs sampling and testing is required quarterly. The process requires a sample which costs $500 and a blank which also costs $500, so LRWSS pays at least $4,000 a year for testing.
According to Aguayo, treatment options for elevated PFAs include granular activated carbon (GAC), anion exchange (AIX) or nanofiltration/reverse osmosis (NF-RO). GAC is better at removing long-chain PFAs, is less energy-intensive than RO and media may be replaced. However, it is less effective for short-chain PFAs, requires a pressure vessel or independent treatment and media disposal may be an issue. AIX is better at removing short-chain PFAs, but disposal of resin is an issue. NF-RO is effective at removing long and short-chain PFAs, but is energy-intensive and costly and disposal of wastes may add to cost.
Reviewing impending regulatory requirements, Aguayo said the EPA is mandating sampling and water testing by 2027, with a requirement to be in compliance with the PFAs limits by 2031 pending proposed rule change from 2029.
In summary, Aguayo said TRA will be working with all of its water system customers to commit funding to construct advanced facilities that will achieve compliance with the applicable EPA requirements to treat for PFAs in drinking water.
