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DETAILS ABOUT GAS 1NFUSION TECHNOLOGY <br /> . Remediation of the hydrocarbon-impacted groundwater will be accomplished by using gas infusion <br /> technology The following is a summary of the technology being proposed <br /> 1 <br /> OXYGEN INFUSION <br />' Oxygen infusion is a technology that utilizes patented gas to liquid mass transfer devices or probes <br /> to enrich the dissolved oxygen(DO) content of groundwater without causing aeration and <br /> volatilization of organic compounds The gas infusion devices consist of a micro-porous polymeric <br />' hollow fiber with micron size holes that create a large surface for <br /> two-inoxych dien ameersion ter er wellheThe <br /> stainless steel covered probes are suspended down-hole located in the <br /> probes are connected to commercial grade cylinder of <br /> €ncdanu be&���oxygen thrange of 40 to 50 <br />' treatment compound Supersaturation levels of oxygen <br /> milligrams per liter(mg1Q with a minimum of 5 to 10 feet of water column above the probe High <br /> DO levels have been related to increased rates of MME and total VOA degradation This <br />' technology requires no external power One oxygen cylinder can supply a well for a period of about <br /> one year <br />' Sites that are good candidates for application of this technology are generally moderate to low <br /> porosity soils with the following characteristics- but dissolved phase concentrations of total <br /> (1) have no liquid phase hydrocarbons(LPH), <br /> hydrocarbons, and; <br /> (2) have an existing monitoring well network(2 inches in diameter or larger)that can be used <br /> for infusion and to monitor performance and <br /> lie (3)have a well network that ns spaced on 20 to 30 foot centers <br /> To apply the technology, several wells containing oxygen info§ion probes will be used in the <br /> f <br /> vicinity of the hydrocarbon impacted area Based on data from sites with similar lithology,the <br /> radius of influence for each of the oxygen infusion wells is an estimated 15 feet Trenching will be <br /> installed to a minimum depth of 6 inches,from the wells to a remednatton gas canister storage shed <br /> that will house the system equipment <br /> outer diameterinfus€on probes to the cylindersexible ylene in the tubing <br /> will be installed in the trenohes and used to connect the <br /> compound <br /> Based on manufacturer recommendations,the system should operate at an oxygen flow rate of 15 <br /> cc/min per well or 0 77 cubic feet of oxygen per well The system will be pressured to about 2 to 5 <br /> pounds per square inch(psi) above the maximum static water pressure Prior to system <br /> implementation, a baseline-sampling event will be conducted on groundwater samples through <br /> newly installed infusion wells The samples will be analyzed for the target contaminants, nitrate, <br /> sulfate, ferrous iron, orthophosphate-phosphorous, five-day biological oxygen demand(BODS), and <br /> chemical oxygen demand (COD), alkalinity, <br /> total inorganic carbon,total dissolved solids and other <br /> analyses Total heterotrophs and specific degraders will be evaluated in a microbiological <br /> laboratory to get a background level <br /> DO,redox potential, conductivity,temperature, and pH measurements will be gathered in the field <br /> This data will be used to assess whether sufficient nutrients exist at the site to provide the necessary <br /> conditions for biodegradation If it is concluded that the nutrient levels do not exist,then nutrients <br /> will be added Based on the implementation of tins technology at sites of similar lithology,the <br /> estimated time to reach the remedial objectives will be two to three years <br /> I <br />