California subsidies for manure-based biogas face rising scrutiny over pollution concerns

Tensions are rising in California’s agricultural heartland over state subsidies for manure-based biogas that are meant to help reduce planet-warming emissions but that environmental groups and locals argue are enabling widespread pollution.

The California Air Resources Board (CARB) will vote next month on whether to lock in the subsidies, which the Golden State has for years been offering to industrial dairies for installing technology that deploys bacteria to break down animal waste and then repurposes it as “renewable natural gas.” California officials argue these anaerobic digesters are environmentally beneficial because they capture methane, a gas produced by dairy cows that is about 28 times more potent than carbon dioxide.

But environmental groups and some residents of California’s Central Valley contend the technology also generates dangerous byproducts and encourages the propagation of polluting factory farms in vulnerable communities.

The digesters emit byproducts like ammonia, nitrous oxide, residual methane, hydrogen sulfide and other odorous gases, according to a new report from nonprofit Friends of the Earth, which slammed the process as no more than “greenwashing.”

The crediting for the subsidies occurs via the state’s Low Carbon Fuel Standard, an initiative launched in 2011 that requires fuel producers to meet specified carbon intensity standards — either by using lower-carbon resources themselves or by acquiring credits from industries that do so.

The Low Carbon Fuel Standard allows dairy farmers to earn such credits by installing the digesters, due to their capacity to capture methane.

At a public hearing held by CARB last month, however, activists criticized the Low Carbon Fuel Standard and its crediting system for perpetuating a technology that they believe is anything but renewable.

“The Low Carbon Fuel Standard does not consider co-pollutants,” Phoebe Seaton, co-founder and co-executive director of the Leadership Counsel for Justice & Accountability, an environmental advocacy group, said at the hearing.

The standard, she continued, fails to account for greenhouse gas “emissions both upstream and downstream associated with the creation of manure, the conversion of manure to methane gas and the disposal of the waste product.”

Meanwhile, this week’s Friends of the Earth report argued that the manure digesters are not only producing dangerous emissions themselves, but they are also driving the expansion of concentrated animal feeding operations (CAFOs) — also known as “factory farms” — due to the convenient crediting system. 

“I can reach out my hands and I feel like I can touch a cow,” Josefa Gonzalez, who has lived in the small town of Pixley, Calif., for the past 19 years, told The Hill. “Our community is really small, and it’s completely surrounded by agricultural fields, where there’s fumigation and fertilizer.”

Gonzalez’s tiny town is located in Tulare County, in the heart of California’s Central Valley and agriculture core. Tulare County is home to about 11 percent of the country’s so-called manure digesters: 49 dairy-adjacent facilities that harness a usable resource from the feces of area livestock, according to the Friends of the Earth report.

The county now has about 295 such industrial-scale CAFOs and is home to around a third of California’s cows, per the report. Most of the county’s dairy facilities have 500 or more cows on site, the authors added.

“There are more cows here than there are people,” Gonzalez said.

At the September hearing, Sam Wade of the Coalition for Renewable Natural Gas, a trade group that advocates for the industry, maintained that crediting the methane-capturing systems “has not created any measurable change in relative herd sizes at farms with digesters versus those without.”

“The incentive-based approach is working,” added Katie Davey, of the Dairy Institute of California, a trade association representing dairy producers in the state.

 The credits for the manure digesters, she contended, are “allowing California’s remaining thousand family-run dairy farms to achieve world leading reductions in methane.”

“These dairy farms are the backbone of our sector, which is critically important to our state, both in terms of community health and economic well-being,” Davey added. 

Nonetheless, the Friends of the Earth report alleged that multiple CAFOs in Tulare County have registered different herd sizes in county, federal, state and Low Carbon Fuel Standard records. As such numbers are self-documented, the authors called for third-party verification of both herd size and methane emissions monitoring.

Meanwhile, the report stressed that more than 93 percent of CAFOs in Tulare County are endangering area water quality via surface contamination with substances like nitrates. Air quality is also a concern, due to the presence of fine particulate matter and ozone, according to the report.

Water and air pollution linked to CAFOs, the authors warned, is disproportionately impacting low-income populations and communities of color. In Tulare County, they added, about 67 percent of residents are Hispanic/Latinx and 18.2 percent are living in poverty.

The Coalition for Renewable Natural Gas pushed back on the report’s findings in a statement to The Hill.

“This report relies largely on qualitative arguments, selective data, and interviews with four Tulare County residents to ineffectively question the repeatedly demonstrated environmental benefits of dairy digesters,” said Dylan Chase, public relations manager for the group. “Despite attempts to stir up controversy to the contrary, digesters represent a low-cost, sustainable means of managing manure methane, which is the direct result of consumer demand for dairy products, as well as an avenue through which we can capture low-carbon biogas and RNG to replace highly pollutive fossil gas and diesel throughout our energy system.”

Gonzalez described an environment of increasingly hot weather mixed with putrid smells in Tulare County.

While poor air quality has made allergies worse for some of her family members, Gonzalez said what is even scarier is the area’s water contamination. She purchased and installed a home water filtration system but still feels like she can “taste the contaminants in this water.”

“Every time I go to the refrigerator and I get some water, I have to bless the water,” Gonzalez said.  “Every day, I do a blessing because I’m scared. And I know that the only person that can protect us from this water is God.”

The subsidy issue may not be the only biogas-related item on the table at CARB’s November meeting, as the agency may also begin exploring its eventual mandate to regulate livestock-related methane emissions.

A 2016 bill, SB 1383, tasked the agency with adopting rules for reducing methane emissions in dairy operations and in livestock manure management. But the legislation also instructed CARB to do so no earlier than 2024 and only following wide-ranging consultations with stakeholders.

At the September meeting, however, board member Diane Takvorian asked the agency’s professional staff members “to prepare a plan for initiating, developing, and presenting for adoption consideration and implementation a livestock methane regulation.”

Noting that legislative code requires CARB “to get this done,” Takvorian asked that “an element to the resolution” be up for consideration at their November meeting, with the goal of beginning rulemaking and rule development in 2025 and adopting a rule for 2030 implementation by 2028.

As far as the local community is concerned, Gonzalez said she would like to see regulations restricting the number of cows each farm can contain. She also stressed her belief that dairies should shoulder more of the burden linked to skyrocketing water prices and worsening water quality in a drought-rattled region.

“We’re getting cards in the mail that have warnings for our water — that says if you start feeling sick, you need to go to the doctor,” Gonzalez said. “That’s terrifying.”

“We know what we see, we know where we live,” she added. “We’re completely surrounded by contamination.”