Oxygen Isotope and Carbon Dioxide Analyzer for Measurements of Respiratory Quotients and Mechanisms in Soil and Dissolved Gases

DOE manages one of the largest groundwater and soil remediation efforts in the world and is responsible for the remediation of 6.5 trillion liters of contaminated ground water and 40 million cubic meters of contaminated soil generated at over 7000 discrete sites. These efforts often involve bioremediation, in which substances are injected into the subsurface to enhance microbial decomposition, and natural attenuation, in which natural, unaided processes are used to remediate waste. In order to assess, optimize, and better understand bioremediation, DOE researchers are actively studying the microbial activity in soil. In this Small Business Innovative Research (SBIR) program, Nikira Labs Inc. proposes to develop a field- deployable, laser-based analyzer capable of simultaneously quantifying O2 concentration ([O2]), n18O in O2, and CO2 concentration ([CO2]) in soil and dissolved gases. The analyzer, which will utilize an innovative, new technology termed incoherent Cavity Ringdown Spectrometry (iCRDS), will provide real- time measurements of respiratory quotients and oxygen production/consumption mechanisms for detailed studies of microbial activity. The resulting system and its data can be utilized by the Subsurface Biogeochemical Research (SBR) program in the Department of Energy to assist bioremediation efforts and better understand the subsurface environment. In Phase I, Nikira Labs Inc. will fabricate a novel, gas cell that will enable multiple iCRDS measurements near 760 nm and 1600 nm for the accurate quantification of 18O in O2, [O2] and [CO2] respectively. The analyzer will be extensively tested on a series of gas standards to determine its accuracy, precision, dynamic range, time response, and thermal stability. The system will then be used by Professor Joe von Fischer in the Department of Biology at Colorado State University to measure soil gases in both unperturbed and amended incubated soil samples. These tests will clearly demonstrate the efficacy of the SBIR instrument in quantifying bioremediation rates and pathways. Finally, the Phase I results will be used to design a Phase II prototype for continuous, real-time field measurements of both soil and dissolved gases. In addition to its value in studying the subsurface, the SBIR instrument has several commercial applications in environmental research, waste remediation, and water resource management. As discussed in detail in the Phase I Commercialization Plan, Nikira Labs Inc. anticipates that these 3 markets will provide cumulative sales revenues of $59.7M during the first 10 years of commercialization.