Micro-Fluidic Spectrometer for Measuring Groundwater Contamination

DOEs efforts to monitor legacy sites for groundwater contamination would benefit from turn-key systems that can measure metal contaminant concentrations in situ. Southwest Sciences proposes to develop a micro-fluidic sensor for measuring heavy metals in groundwater by measuring their uv-visible spectra. High sensitivity will be obtained using cavity enhanced spectroscopy. A novel cavity enhanced optical detection method will be demonstrated that will allow operation at the short photon lifetimes characteristic of cavities in micro-fluidic channels. The objectives of the Phase I research include (1) demonstrating the detection approach using a conventional cavity, (2) developing a micro-cavity with the novel detection method, (3) using this system to measure chromium concentrations, and (4) outlining the design of a fully-engineered system. In Phase II the micro-cavity will be incorporated with micro-fluidic pumps and filters to provide a complete sensor system. The Phase II effort will culminate with tests at a DOE facility. In Phase III we will address a wide range of industrial and environmental monitoring applications.