3.3 Explore local options for sustainable biosolids disposal given changing market conditions

Key Message: Biosolids are transported from wastewater treatment facilities to processing and disposal locations around the state, making them a statewide issue. FDEP’s 2021 updates to biosolids regulations will improve water quality protection and establish stricter criteria for assessing the suitability of land-spreading sites. However, local governments should closely follow possible changes in market conditions due to stricter disposal rules and emerging concerns around unregulated chemical contaminants.

Importance

Better nutrient management of land-applied biosolids is critical to minimizing nutrient pollution of water bodies. Land spreading of biosolids has contributed to excess nutrients, particularly phosphorus, in watersheds, impairing water quality for years to come (see Chapter 3.1). Additional concerns involve bioaccumulation of unregulated toxins remaining in biosolids even after Class AA processing, including industrial chemicals, household products, and pharmaceuticals (see Chapter 3.2). Because biosolids are transported across the state, effective management of their disposal is both a local and statewide concern.

Overview

In 2021, revisions to biosolids regulations (Chapter 62-640, F.A.C.) proposed by the Florida Department of Environmental Protection (FDEP) were adopted into law. These revisions are intended to minimize nutrient loading to water bodies—particularly phosphorus—by more strictly regulating nutrient loads applied to land. Sarasota County’s ordinance on biosolids land spreading references FDEP regulations and requires strict permitting (Sec. 54-188).

FDEP’s rule revisions were informed by a Biosolids Technical Advisory Committee (TAC) composed of environmental and agricultural experts, utilities, waste haulers, consultants, and academics. Major changes include more precise nutrient management plans for land application sites, targeted to actual soil deficiencies and crop needs, ensuring nutrients are fully utilized by plants rather than accumulating or migrating offsite. Additional groundwater and surface water monitoring and reporting are also required.
Revisions to Chapter 62-640 apply to new site permits and renewals after July 1, 2020, and include:

• Compliance with Basin Management Action Plans and revised nutrient application rate determinations
• Groundwater and surface water monitoring requirements
• Prohibition of land application where the seasonal high-water table is within six inches of the soil surface (or depth of biosolids placement)
• Requirement for a minimum two-foot separation between biosolids placement depth and the seasonal high-water table
• Mandatory enrollment of biosolids sites in an FDACS Best Management Practices (BMP) Program

However, the revised rules do not address concerns about the bioaccumulation of unregulated pollutants such as PFAS, industrial chemicals, microplastics, or pharmaceuticals.

Approach

With the adoption of FDEP’s new biosolids rules to minimize nutrient loading to waterbodies, the biosolids disposal market may experience an oversupply. Counties should follow these market trends closely and consider alternative means of disposal (see Chapter 3.2), especially if unregulated toxic contaminants such as PFAS and pharmaceuticals in biosolids become a concern for the public acceptance of processed biosolids.

Sarasota County Public Utilities and Solid Waste are considering local biosolids processing options. It may be advantageous for Sarasota County to co-locate a biosolids/greenwaste composting facility (see Chapter 4.7) or a biosolids energy facility at its Central County Landfill. This could take advantage of the available green waste delivered to the landfill, provide safe disposal of biosolids, while creating a sufficient buffer from residences and businesses for such operations. However, the processing of biosolids should effectively remove toxic contaminants, such as per- and polyfluoroalkyl substances (PFAS) and pharmaceuticals, in order to ensure a safe and sustainable byproduct that does not further contaminate the environment (see Chapter 1.2).

Resources

• FDEP Chapter 62-640 F.A.C Rulemaking

Status

Revisions to FDEP biosolids regulations adopted into law June 2021

Performance Measure

Macroeconomic study of Florida-based biosolids processing and disposal opportunities

Experts or Leads

Maurice Barker, FDEP Biosolids Coordinator

Cost Estimate

< $10,000

Related Activities

Chapter 3.2