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Biosolids

Control of Pathogens and Vector Attraction in Sewage Sludge

This document is not regulatory in nature and is only intended to serve as a guide to pathogen and vector attraction reduction for anyone who is involved with the treatment of sewage sludge for land application. This guide was previously released in 1993. The updates and amendments to this document are a product of comments and suggestions from the regulatory and sewage sludge management community.

This document provides basic information about why pathogen control and vector attraction reduction in biosolids are essential for the protection of public health and the environment. Topics include:

  • Current federal requirements under Subpart D of Part 503
  • The different Processes to Further Reduce Pathogens (Class A) and Processes to Significantly Reduce Pathogens (Class B) processes
  • Role of EPA's Pathogen Equivalency Committee
  • Vector attraction reduction issues
  • Sampling and analysis protocols used to meet the quantitative requirements of Part 503
  • References and additional resources related to biosolids use
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