*** 9761250 Nemser This is a Small Business Innovation Research Phase I proposal. Certain remediation facilities generate waste streams containing high concentrations of nitrite and chlorinated aliphatic hydrocarbons. These can be destroyed biologically using dissolved hydrogen gas as the electron donor. Hydrogen offers several economic and operational advantages over other organic electron donors in denitrification and in reductive dehalogenation. The factor limiting hydrogen use is its low solubility, i.e. existing commercial gas-dissolution technologies cannot dissolve sufficient hydrogen in a safe, cost effective manner. Membrane-based gas-dissolution technologies can potentially supply the hydrogen required for these processes safety, but commercially available membrane suitable for bubble-free gas-dissolution have poor performance, biological fouling, or both. Compact Membrane Systems, Inc., has developed a highly gas permeable perfluoropolymer coating for microporous membranes. The smooth, non-porous nature of the perfluoropolymer coating is highly resistant to biological fouling, especially compared to microporous hydrophobic membranes. This coating could remove the performance, fouling, and cost barriers that preclude the use of membrane-based gas dissolution technologies in continuous biological processes. The proposed study will demonstrate the technical feasibility of using perfluoropolymer-coated membrane devices as the hydrogen source for biological denitrification of high concentrations of nitrate and nitrite. In addition to nitrate, nitrite and chlorinated hydrocarbon removal, these perfluoromembranes can be used to transfer many other gases into or out of water. Examples include: oxygenation of bioreactors for enhanced cell growth, oxygenation of aquaculture, oxygenation of wastewater, ozonation of drinking water for enhanced quality and safety. This broad base of utilization should lead to both high probability of commercial success plus a large sales base to allow for lower pricing in remediation markets. ***