Attenuation of Emerging Contaminants in Streams Augmented with Recycled Water
Year Released: 2011
Funding Partner: Bureau of Reclamation, Santa Clara Valley Water District
Total Investment: $153,901.53 (Cash)
Principal Investigators: Megan H. Plumlee, Ph.D., Kennedy/Jenks Consultants, Christopher J. Gurr, CDM Smith, and Martin Reinhard, Ph.D., Stanford University
Water recycling for environmental applications requires consideration of a complex set of benefits and risks. The present study was a research effort designed to supplement a planned pilot project. The pilot project was initiated by the Santa Clara Valley Water District to demonstrate the feasibility of stream flow augmentation with recycled water. The supplemental research effort evaluated the hypothesis that potential impacts of wastewater-derived organic contaminants may be mitigated by natural attenuation of those compounds during stream flow.
Goals and Objective
The project developed insights into attenuation mechanisms with a focus on N-nitrosodimethylamine (NDMA) and perfluorochemicals, contaminants that have not previously been considered in such an undertaking.
Laboratory investigations of environmental fate included biodegradation, sorption, and photolysis of particular organic contaminants. Field site assessment included water quality constituent selection and campaigns of sampling recycled water and site water.
Findings and Conclusions
The report presents the lessons learned from the collaborative work to implement a stream flow augmentation pilot project. The results of the environmental impact review of the project, conducted pursuant to the California Environmental Quality Act, are included in this report, as is a discussion of the technical and programmatic challenges faced by the project team. The augmentation was ultimately cancelled because the investigation detected compounds that posed potential legal vulnerability. Unknown compounds and compounds with undefined regulatory limits make the environmental impact review process difficult and implementation of water recycling unpredictable.