Biosolids at the Crossroads of Agriculture and Public Trust

Written by Gabriel Flores (Government Relations Intern)

Arizona's constant growth poses new questions, threats, and even opportunities at the intersection between agriculture and urban development. On the legislative side, there is increased attention to biosolids, a byproduct of wastewater treatment, which, if managed correctly, can aid soil health. A recent influx of bills in the Arizona legislature is focusing on how biosolids can be implemented under the following criteria: responsible and transparent usage, and priority to public and soil health.

"What goes into the soil matters."

What Are Biosolids?

Organic materials generated during wastewater treatment are classified as biosolids. They contain important nutrients that improve the difficult soil structure found in Arizona.

According to the U.S. Environmental Protection Agency (EPA):

“Biosolids are nutrient-rich organic materials resulting from the treatment of domestic sewage in a treatment facility. When treated and processed, biosolids can be safely recycled and applied as fertilizer to improve and maintain productive soils sustainably.”

Even though biosolids are controversial, they are only utilized if they are highly regulated and intended to support soil health. They are not intended to fully replace our farmers' good management practices. 

Well-defined, scientifically grounded regulations help guarantee:

• Agricultural soils remain safe and productive.

• Environmental and public health regulations are respected.

• Trust is upheld between agricultural producers and urban communities.

The Significance of Biosolids in Maricopa County

Maricopa County is situated where working agricultural lands and fast urban growth converge. Wastewater generation increases with population, raising significant concerns about the responsible management of byproducts.

Farmers must simultaneously contend with rising input costs and the ongoing pressure to sustain soil productivity in arid conditions. Waste management is only one aspect of biosolids policy; another is the coexistence of agriculture and urbanization. Recent innovation, however, is turning problems into solutions. Let's take a look.

HB 2640: Preserving What Enters the Soil

House Bill 2640, which addresses PFAS, also known as "forever chemicals," is a new piece of legislation that impacts this conversation. The eco-toxicity of these chemicals, however, has made them a focal point in the United States.

Fertilizers containing PFAS, including biosolids, are restricted under HB 2640, a bill that establishes compliance deadlines years in advance. The goal is to avoid long-term soil contamination while providing lead time to allow for monitoring and research.

The sense of this bill is to preserve food safety and soil integrity without disrupting anything immediately. For the average citizen, it appears that their legislature is aware of new scientific discoveries and is addressing issues consumers are concerned about.

Fundamentally, the question posed by HB 2640 is quite simple: What belongs in the soil our food grows in?

Oversight and Transparency: SB 1336

The Arizona State Land Department will receive temporary oversight through Senate Bill 1336, which establishes an interim committee to supervise its operations. The committee investigates how State Trust Lands uses biosolid materials.

Maricopa County needs this information because State Trust Lands exist throughout the county, and people use them for agricultural purposes. The law restricts biosolid use through its requirement that organizations must report their activities while biosolid use remains permitted.

The bill establishes public reporting requirements to improve land management operations and environmental enforcement procedures according to the new requirements. The system helps both agricultural producers and their neighboring communities through its transparent oversight mechanism.

Biosolids Are Already Regulated

The current regulations govern biosolids disposal methods. The public must understand this essential fact because biosolids exist under existing regulatory control.

The Environmental Protection Agency controls biosolid regulations through 40 CFR Part 503, which establishes treatment testing application rate and site restriction standards.

The Arizona Department of Environmental Quality (ADEQ) uses its permitting and compliance enforcement duties to enforce these standards throughout the state of Arizona. The new legislative proposals extend existing regulations, yet they do not eliminate current rules. The system enhancements provide better scientific data while considering public knowledge and Arizona's particular agricultural and urban environments.

How These Bills Work Together

The biosolids-related bills develop different solutions for the same system. The two bills investigate separate aspects of the system. The first bill establishes which materials become suitable for land treatment. The second bill designates the authorities who will manage land use and compliance responsibilities. Biosolids treatment and application processes must follow existing ADEQ and EPA regulations. The multiple levels of this system demonstrate the legislative objective to establish protective measures that enable responsible land management.

The Bigger Picture for Arizona Agriculture

The agricultural sector in Arizona will maintain its essential role for land management, resource management, and sustainable development throughout the state's growth period. The regulations governing biosolids demonstrate how essential cities, regulatory authorities, and agricultural producers to work together to achieve effective results. The established standards establish protection for soil and water and public trust while they grant producers the operational requirements they need for responsible work. The two parties must maintain their equilibrium in Maricopa, which serves as a rapidly expanding county.

References

Arizona Department of Environmental Quality. Biosolids Management Program. ADEQ, https://www.azdeq.gov/biosolids.

Arizona Legislature. House Bill 2640. Arizona State Legislature, 2026, https://www.azleg.gov.

Arizona Legislature. Senate Bill 1336. Arizona State Legislature, 2026, https://www.azleg.gov.

U.S. Environmental Protection Agency. Biosolids. EPA, https://www.epa.gov/biosolids.

U.S. Environmental Protection Agency. Standards for the Use or Disposal of Sewage

Sludge (40 CFR Part 503). EPA, https://www.epa.gov/laws-regulations/summary-standards-use-or-disposal-sewage-sludge.

U.S. Department of Agriculture, Natural Resources Conservation Service. Soil Health. USDA NRCS, https://www.nrcs.usda.gov/soil-health.