Treatment of N-Nitrosodimethylamine (NDMA) in Groundwater Using a Fluidized Bed Bioreactor
ER-200829
Objective
N-Nitrosodimethylamine (NDMA) is a known potent carcinogen and an emerging groundwater contaminant that is prevalent at numerous Department of Defense (DoD) installations. At military and National Aeronautics and Space Administration (NASA) installations involved in the production, testing, or disposal of liquid rocket propellants containing 1,1-dimethylhydrazine, NDMA is often present in groundwater. Due to its carcinogenicity, the California Office of Environmental Health Hazard Assessment (OEHHA) recently established a public health goal (PHG) for NDMA in drinking water of only 3 ng/L (i.e., 3 parts-per-trillion). Currently, the only effective treatment technology for NDMA in groundwater is pump-and-treat with ultraviolet (UV) irradiation. However, this approach is expensive. The objective of this proposal is to demonstrate and validate the use, performance, and cost of a biological fluidized bed reactor (FBR) for the treatment of NDMA in groundwater.
Technology Description
This Environmental Security Technology Certification Program (ESTCP) project builds on the successful results from Strategic Environmental Research and Development Program (SERDP) Project ER-1456, the objective of which is to examine the potential for in situ and ex situ biodegradation of NDMA in groundwater. From this study, it was determined that propanotrophs, such as Rhodococcus ruber ENV425 were capable of cometabolizing NDMA in a membrane biological reactor (MBR) from typical groundwater concentrations (e.g., 1-80 µg/L) to low part-per-trillion levels. Propane does not appear to appreciably inhibit this reaction. Such data suggests that ex situ biological NDMA treatment to regulatory levels is both feasible and sustainable. However, an MBR is likely not the optimal design for cost-effective treatment of NDMA-contaminated groundwater at full-scale. Therefore, in this ESTCP demonstration, an FBR will be tested for NDMA removal from water. The FBR is an efficient fixed-film bioreactor in which a high concentration of biomass is attached onto fluidized medium. Within the fluidized medium, biological treatment of the contaminated water occurs. In laboratory studies, the particular NDMA degrading microorganism, R. ruber ENV425, has been shown to develop an extensive biofilm that may be highly suitable for optimal performance in an FBR. This concept will be demonstrated through initial lab characterization studies, followed by a pilot-scale demonstration at a suitable site with groundwater contaminated with NDMA.
Benefits
A successful demonstration of the FBR technology in the lab and in the field, using the NDMA degrading microorganism R. ruber ENV425, will provide DoD with a widely applicable ex situ remediation approach for NDMA. UV treatment is presently the only practical method used to remove NDMA from groundwater. Although this technology is effective, it is also very expensive because of the necessary electrical requirements. With the increase in the cost of electricity, and the likelihood that further state or federal regulations for this carcinogen will occur in the future, it is important to evaluate potentially less expensive treatment options for this compound. This demonstration will assess a biological treatment approach with the potential to be both effective and economical. (Anticipated Project Completion - 2012)
Points of Contact
Principal Investigator
Dr. Paul Hatzinger
CB&I Federal Services
Phone: 609-895-5356
Fax: 609-936-9221
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.