This project involves the development of an advanced underwater mass spectrometer capable of on-site measurement of dissolved gases and chemicals of concern in both marine and freshwater systems. Mobilizing cutting edge instrumentation for continuous measurements coupled with real-time geospatial mapping will transform our ability to rapidly assess environmental quality and protect human health. The research enabled by this project includes monitoring environmental changes with unprecedented resolution over time and space with applications to clean harbor remediation, sustainable aquaculture, and estuary dynamics. The infrastructure will also play a key role in tracking hazardous substances resulting from transportation and exploration activities. Timely, in-field information is critical in providing decision support in response to an emergent spill or critical incident. To our knowledge, this will be the first device of its kind in Canada with unique integrated hardware and software capabilities for measuring a range of chemical contaminants, biomarkers and dissolved gases.