The need for real time monitoring of biogeochemical processes in the environment is of paramount importance in understanding the relative oxidation states of key elements that directly impact an area under study. From Superfund sites to ground water aquifers the ability to identify and measure pollutants is important to the water infrastructure of our country. There is limited understanding of these key redox elements using current physiochemical field methods. Traditional physical data from a site and/or water samples from the site of interest are taken back to a lab where in-situ processes are inferred. This approach is fraught with error since real time chemical measurements are not being taken on the time scale required for correct and more detailed interpretation. Samples removed from an environment can change chemically and may not reflect exact chemical processes critical in the understanding required to make sound decisions for a sitesÂ’ remediation. The purpose of this Phase I SBIR is to develop and construct a working prototype of an instrument that can perform in-situ biogeochemical analysis. The instrument will allow the user to place a sensor directly into an area that is to be studied. The user will select the element or elements required for study, and real time data will give a clearer understanding of environmental processes. The benefit of such an instrument will allow many researchers, public utilities personnel, wastewater management personnel, and potable water management personnel, to monitor in real time chemical species that are of concern and to indicate quantative levels of those species or contaminants. The need for such instrumentation is evident when catastrophe occurs from deep ocean oil spills to acid mine drainage contamination of our rivers and subsurface aquifers. As stated in the solicitation the ability to distinguish between relevant oxidation states of redox elements such as dissolved oxygen, sulfide, iron, iron sulfide, manganese and others that are of particular concern. These species lend themselves to an electrochemical analysis approach since what is being measured is an electrochemical process. In Phase II prototype instruments that can be deployed on a broad scale will allow for a more complete understand of the site under study. Analytical Instrument Systems will take spot samples while our instruments are running to insure accuracy and precession. Analytical Instrument Systems will continue to refine the electronics and sensor portion of this instrument until it becomes the new forefront of in-situ chemical analysis technology and becomes as common an instrument as a portable pH meter. With the ever-rising problems of drinking water contamination and the treatment of wastewater from landfills, an inexpensive way of sensing containments is required. A new chemical analysis tool is being developed that can identify chemical contamination of any water system, potable water, rivers, lakes, wells, and ocean environments within seconds.