A Collaborative Approach to Development of a PCB Model and TMDL for the Delaware Estuary Author: Charles App Key Words: PCB, model, TMDL, fish advisories Fish consumption advisories for channel catfish, white perch, striped bass, and several other species exist for the entire Delaware Estuary (Pennsylvania, New Jersey and Delaware) due to PCB contamination. The states have listed toxics/PCBs on the 303(d) list of impaired waters; and the Delaware Estuary Program, one of 28 National Estuary Programs in the country, has identified PCBs as a program priority. In addition, EPA is required to ensure that a total maximum daily load (TMDL) for PCBs is completed by December, 2003 as a result of a Court mandated settlement. In order to address the state-of-the-art technical issues of developing a PCB model and a TMDL for PCBs, a Toxics Advisory Committee (TAC) has been established by the Delaware Estuary Program and the Delaware River Basin Commission (DRBC). The TAC is composed of a diverse group of stakeholders; EPA, states, the DRBC, municipalities, industries, academia, and environmental group representatives working together to oversee development of the PCB TMDL for the Estuary. The DRBC is responsible for developing the state-of-the-art PCB model of the Estuary and the PCB TMDL for the states and EPA. An Expert Panel has also been established to advise the TAC. One of the experts on the Panel that is advising on the development of the PCB model is from the ORD Environmental Research Lab in Athens, GA. EPA is also assisting this effort with Regional Applied Research Effort (RARE) funding. While this collaborative stakeholder-involved process requires a considerable investment of time and effort for all involved, it is felt that the benefits in terms of TMDL implementation are significant and worth the “cost.” For significant, highly visible, interstate water quality issues requiring development of TMDLs, this unique approach to TMDL development should be considered. Contact Information: Charles App Director Office of Ecological Assessment & Management, Region 3 215-814-2757 app.charles@epa.gov