The Rundown

• EPA releases draft health risk assessment for two PFAS in biosolids.
• EPA publishes final toxicity review for inorganic arsenic, a naturally occurring drinking water contaminant.
• USGS releases study on water supply and demand in the Lower 48 states.
• EPA evaluates environmental impact of federal biofuels mandate.
• New study assesses potential for floating solar panels on federal reservoirs.
• EPA appeals a court ruling that it must strengthen fluoride regulation.
• President Biden issues an executive order to facilitate next-generation AI data centers using federal lands.
• Reclamation distributes ecosystem restoration funds for the upper Colorado River basin.

And lastly, President Biden designates two new national monuments in California.

“This draft assessment is focused on a specific and likely narrow population of people that EPA considers most at risk because they are most likely to be exposed to PFAS-contaminated biosolids that are land applied and can enter groundwater, surface water, and products that people eat.” – Zach Schafer, director for policy and special projects at the EPA Office of Water, speaking on a January 15 webinar about the agency’s draft assessment of the health risks of two PFAS in biosolids.

Schafer added that the assessment highlights “the importance of federal and state policies to control and remove PFAS at their source.”

By the Numbers

2: New national monuments designated by President Biden. They are Chuckwalla National Monument, a 624,270-acre plot in southeastern California, and Sáttítla Highlands National Monument, a 224,676-acre volcanic landscape in the northern part of the state.

$388 Million: Funding for drought response in the upper Colorado River basin. The money will support 42 ecosystem and habitat restoration projects in drought-affected areas.

News Briefs

Fluoride Appeal
The EPA appealed a September ruling in federal district court that the agency needs to regulate fluoride in drinking water, Bloomberg Law reports.

Studies and Reports

Slippery Sludge
The EPA released its first human health assessment of PFAS in biosolids, finding evidence that in certain cases, the toxic chemicals lodged in treated sewage sludge are a risk to people.

The assessment, issued in draft form, is limited to just PFOA and PFOS, the most-studied chemicals in this class of several thousand compounds. The agency evaluated risks to people living on or near lands where these biosolids are applied. The analysis also considered risks for people whose primary consumption of water and food comes from these lands. It is not intended to assess risk for the general public.

Biosolids are generally disposed of in three ways: spread on land as fertilizer, burned, or put in landfills.

“All of the [disposal] options pose some level of risk of PFAS exposure to people,” said Zach Schafer, director for policy and special projects at the EPA Office of Water. The challenge for his agency is to determine what level of risk is acceptable.

The highest risks in the scenarios that EPA modeled were:

• drinking milk from pasture-raised cows that had contaminated feed or water
• drinking water from contaminated wells
• eating fish from a lake contaminated by runoff
• eating beef or eggs from pasture-raised animals consuming contaminated feed or water

These risks vary according to local climate, geology, land application quantities, and contaminant concentrations.

The draft assessment sets the stage for future regulatory action on PFOA and PFOS in biosolids.

Currently the agency sets limits in biosolids for pathogens and nine heavy metals.

Public comments on the draft are being accepted through March 17 at www.regulations.gov using docket number EPA-HQ-OW-2024-0504. The agency is interested in data on how chemicals move from soil and water into animals and plants.

In context: Fertilizer from Sewage, a Utility Money Maker, Faces Uncertain Future

Inorganic Arsenic Health Risk Assessment
The EPA’s chemical risk assessment division published a final review of the toxicity of inorganic arsenic, a naturally occurring drinking water contaminant.

The review builds on a previous assessment from 1995. Inorganic arsenic is a carcinogen, and the update also finds strong evidence for links to heart disease, hypertension, and diabetes.

Floating Solar Panels
Researchers at the National Renewable Energy Laboratory estimated the potential generating capacity from floating solar panels in federal reservoirs.

The number ranges from 861 gigawatts to 1,042 gigawatts. On the low end that represents half of the solar energy capacity needed to decarbonize the U.S. grid by 2050.

Each of the 846 reservoirs in the study has a different developable area that depends on factors like water current and the slope of the lake bottom.

Water Supply and Demand
The U.S. Geological Survey released a study on water availability in the United States.

The study, which covers the years 2010-2020, finds that 26.7 million people live in areas with severe water limits. A disproportionate number of these people have social disadvantages – low income, few public services – that make them more vulnerable to water scarcity. These areas include California’s Central Valley and the Rio Grande Valley of Texas.

The report also looks at water quality as a factor that limits availability, as well as how water is used in the country. The biggest water user is crop irrigation.

Biofuels and the Environment
The federal biofuels mandate, now 20 years old, has “modest negative impacts” on air, land, and water nationally, according to a new EPA analysis.

In a report to Congress, the agency found it difficult to disentangle the effects of the federal mandate from market changes and other factors that influence cropland given over to biofuels.

Nonetheless, in areas that had already lost wetlands, experienced groundwater depletion, or witnessed nutrient pollution, the federal mandate “represents additional strain on already strained ecosystems.”

On the Radar

Tribal Water Rights
Congress, before adjourning last session, did not approve a historic water rights settlement for tribes in northeastern Arizona. The Colorado Sun looks at what’s next for the deal.

Cabinet Nominees
Senate committees held hearings last week for the energy and environment Cabinet positions. They are likely to begin voting this week.

AI Infrastructure
In one of his last acts, President Biden is seeking to maintain U.S. leadership in artificial intelligence.

The executive order directs the departments of energy and defense each to select three sites on land they manage that could be suitable for a next-generation AI data center.

The land would be leased to a non-federal group, which would build the center and renewable energy facilities to serve it.

Some data centers are water hogs, so the order requires development of federal reporting standards on water use and greenhouse gas emissions. The Energy Department is also directed to increase R&D for using heat from wastewater as a data-center power source.

The timeline for site selection is short – by February 28, 2025.

Federal Water Tap is a weekly digest spotting trends in U.S. government water policy. To get more water news, follow Circle of Blue on Twitter and sign up for our newsletter.