—Alan Dulaney
The Drought Contingency Plan was signed by all seven Basin states and the Department of the Interior on May 20, 2019, at Hoover Dam. Done is done. But what was happening at the Federal level while all eyes were on the politics of the Lower Basin?
Turns out, not so much. The Administration is not aggressively pursuing growth in regulations in the agency most closely associated with water quality, the U.S. Environmental Protection Agency (EPA). Indeed, the proposed FY 2020 federal budget slashes EPA funding by 31%, down to $6.1B. Major cuts have been proposed in previous budgets, but Congress has not enacted the numbers. These proposed cuts also will likely not be passed, but they are indicative of the mindset.
EPA is in no hurry to promulgate new rules or undertake major enforcement initiatives. Nonetheless, they are being carried along by pressure from a worried public. The most famous of the new contaminants of emerging concern are the groups of compounds lumped as poly- or per-fluoroalkyl substances, or PFAS. PFAS have been utilized for decades for everything from carpets to food packaging to firefighting chemicals for their ability to repel water and oils, and are thus widespread across the U.S. The latest newsletter from SGS Labs notes that PFAS have been found in water samples from 610 sites across 43 states, which shows the extent of contamination. Some links have been shown between thyroid cancer and PFAS. It is a large class of compounds, but the two best known are perfluorooctanioic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). Health advisory limits exist for these two compounds, down to 70 nanograms per liter (ng/l) or parts per trillion.
PFOA and PFOS are likely to be listed under CERCLA in late 2019, according to an EPA Action Plan released on February 14. MCLs for these compounds will probably follow in late 2020. Many labs now have equipment that can detect these contaminants down to the parts per trillion range. Detection limits are now down to two ng/l, and better equipment and methods keep on expanding the range at which trace contaminants can be found. The prevalence of PFAS probably wouldn’t be known without the increasing sophistication of American laboratories. Note: Many AHS members work for labs, including SGS. EPA will be looking at new potential analytical methods in the future.
A recent article suggests that one exposure pathway for human populations may be through inadvertent indirect potable reuse. Some 82% of the U.S. population depends on water sources downstream from wastewater treatment plants or under the influence of groundwater that has been recharged by reclaimed water. PFAS compounds in trace amounts can apparently make it through current treatment processes. But dosage levels, other pathways, and even what the appropriate health effects to look for remain under discussion. The American Water Works Association will be releasing a fact sheet soon that will have up-to-date information.
EPA is also looking at risks associated with fish consumption, although surface water quality criteria are not expected before 2022. Risk communication tools will be needed as our understanding of the effects of these compounds on human health grows. People probably ingest more contaminants from taking medications and using cosmetics than from water sources; however, given the public’s growing concern about PFAS, it won’t be easy convincing them that trace amounts may not represent a significant health risk. EPA is also expanding research efforts, including fate and transport, sources, ecological effects, and various treatment and remediation techniques.
The UA recently received a $1.2M grant from the Department of Defense to investigate better ways of remediating PFAS. Granular activated carbon (GAC) can remove these molecules from water, but not very efficiently. The quantity of GAC needed to clean up PFAS plumes in groundwater would not be financially feasible. Better sorbents are needed, and that is what the UA team is looking for.
EPA recognizes that funding constraints and the mandated deliberate pace of introducing new regulations will mean that the various state agencies will be moving more aggressively on PFAS than the EPA for the foreseeable future. However, the public may not be happy with a pace of EPA action that they see as too slow.
Interested in learning more about PFAS? Check out the PFAS workshop that will be held in Phoenix on July 11. This American Ground Water Trust program was organized in cooperation with AHS and in support of the Air & Waste Management Association–Grand Canyon Section.