In 1993, the U.S. Environmental Protection Agency (U.S. EPA) promulgated Standards for the Use or Disposal of Sewage Sludge (Code of Federal Regulations Title 40, Part 503), which establish pollutant limitations, operational standards for pathogen and vector attraction reduction, management practices, and other provisions intended to protect public health and the environment from any reasonably anticipated adverse conditions from potential waste constituents and pathogenic organisms. In California, the beneficial reuse of treated municipal sewage sludge (a.k.a. biosolids) generally must comply with the California Water Code in addition to meeting the requirements specified in Part 503 in Title 40 of the Code of Federal Regulations.

In July 2004, the State Water Resources Control Board adopted Water Quality Order No. 2004-12-DWQ (General Order), and certified a supporting statewide Programmatic Environmental Impact Report (PEIR).

The General Order incorporates the minimum standards established by the Part 503 Rule and expands upon them to fulfill obligations to the California Water Code. However, since California does not have delegated authority to implement the Part 503 Rule, the General Order does not replace the Part 503 Rule. The General Order also does not preempt or supersede the authority of local agencies to prohibit, restrict, or control the use of biosolids subject to their jurisdiction, as allowed by law.

Persons interested in seeking coverage under the General Order should contact the appropriate Regional Water Quality Control Board. Only applicants who submit a complete Notice of Intent (NOI), appropriate application fee, and are issued a Notice of Applicability by the executive officer of the appropriate Regional Water Quality Control Board are authorized to land apply biosolids at an agricultural, horticultural, silvicultural, or land reclamation site as a soil amendment under the General Order.

It is the responsibility of all interested parties to make appropriate inquiries and to obtain any additional federal or local governmental agency permits or authorizations prior to the application of biosolids at each site.

Publicly Owned Treatment Works (POTWs) That Receive Anaerobically Digestible Material

To receive immediate regulatory coverage, Publicly Owned Treatment Works (POTWs) that receive anaerobically digestible material (ADM) for co-digestion must develop standard operating procedures (SOPs) that ensure safe operation of the new ADM receiving and digestion system.  The SOP shall include a spill response and contingency plan, vector and odor control, avoidance of introduction of any materials that could cause upset of the treatment process, and operation and maintenance procedures.  The spill response and contingency plan must outline procedures for spill containment, recovery, and cleanup procedures.  Operations and maintenance (O&M) manuals shall be updated with instructions to properly operate and maintain the system.  In addition, POTWs wishing to receive regulatory coverage must submit a notification letter to the appropriate Regional Water Quality Control Board.  A template notification letter can be found by clicking on the link below:

  • Template Notification Letter

    The notification letter template must be tailored to describe the activity in which you are engaged.  Please retain a copy of the letter on file and incorporate the SOPs into your training program and your Operations and Maintenance Manual.  The SOPs should not be submitted with the notification letter.

Additional information concerning the general order and related environmental documentation:


Questions relating to the statewide biosolids program, please contact: Questions related to obtaining authorization to discharge biosolids, please contact the appropriate Regional Water Quality Control Board.