By James Laughlin
EPA has released a final action plan that explains the Agency's response to recommendations in the July 2002 National Research Council (NRC) report entitled "Biosolids Applied to Land: Advancing Standards and Practices."
Over the past decade, citizens and environmental organizations have questioned the adequacy of the chemical and pathogen standards for protecting human health. As an example, late last year the Center for Food Safety sent a petition to EPA asking for a moratorium on the land application of biosolids. EPA rejected the group's demands, saying there was no scientific basis for the moratorium.
To address the public concerns about biosolids land application, EPA commissioned the NRC of the National Academy of Sciences to independently review the scientific basis of the regulations governing the land application of sewage sludge.
The NRC published its report in July 2002. Researchers concluded that there was no documented scientific evidence that sewage sludge regulations have failed to protect public health, but there is persistent uncertainty on possible adverse health effects.
The NRC noted that further research was needed and made about 60 recommendations for addressing public health concerns, scientific uncertainties, and data gaps in the science underlying the sewage sludge standards.
In April 2003, the Agency released a preliminary multi-year strategy for public comment that responded to the NRC report recommendations. Based on public comments and research priorities from a Biosolids Research Summit held in July 2003 by the Water Environment Research Foundation, EPA developed a final action plan that has four main objectives:
• Determine potential risks of select pollutants
• Measure pollutants of interest
• Characterize potential volatile chemicals and bioaerosols from land application sites
• Understand effectiveness of water/sludge treatment and risk management practices
Due to budget constraints and competing priorities within the Agency, EPA said it would not able to implement all of the NRC's recommendations. Instead, the Agency prioritized the recommendations based on public comment and criteria to help identify research and regulatory measures that, when implemented, will maximize public health and environmental protection.
The Agency expects to complete or begin activities, presented in the notice as "projects," within the next two to three years. An example of the projects planned include conducting field studies of biosolids application sites; conducting a targeted national survey of pollutants in biosolids; developing improved detection and monitoring methods for microbial pollutants in sewage sludge; and participating in "incident tracking" workshops.
EPA also will continue to conduct it's regular biennial review of the biosolids program, as required under the Clean Water Act. The agency just published the results of its most recent review, which involved the evaluation of publicly available information on the toxicity, persistence, concentration, mobility, and potential for exposure of additional toxic pollutants in sewage sludge.
Based on its studies and comments it received, EPA has identified 15 chemicals for which it will conduct a more refined risk assessment and risk characterization process. EPA will update the concentration data on these chemicals by conducting a targeted sewage sludge survey. The new concentration data and results will serve as a basis for determining whether to propose amendments to the sewage sludge regulations for any of these chemicals.
James Laughlin, Editor
