ARCHIVED REPORTS XR0001009 - Laserfiche WebLink

Home Browse Search

Geologccaf Ter"ics Inc Page 7 ' to Situ Remediation Feasibility Study Project No 507 2 . September 20,2002 breakdown process are reported to be bicarbonate, water and small amounts of mineral acid from any halogen, nitrogen or sulfur present in the groundwater ' The AOPs have been very successful at treating gasoline compounds and the gasoline oxygenated fuel compounds AOPs are promising because they quickly destroy the ' contaminant rather then augmenting the relatively slow biological processes at the site Typically AOPs use one or more of the following to create the hydroxyl radical • Hydrogen peroxide • Ozone • Permanganate ' • Fenton's Reagent For this site, a combination of peroxide and ozone would be injected into the subsurface via ' the use of a GeoProbe direct push drill rig The peroxide and ozone would combine to form the hydroxyl radical, which would then break down the BETX and TPH in the groundwater ' and capillary zone at the site 3.4.2 Concerns & Limitations The use of an AOP at this site primarily poses two concerns, formation of byproducts and obtaining an effective radius of treatment The oxidation chemistry is straightforward and byproduct formation should not be a problem A chemistry discussion follows below ' Obtaining an effective treatment area should be obtainable Oxidation Chemistry ' The chemistry to oxidize BTEX and gasoline range hydrocarbons is relatively simple Peroxide will directly oxidize the BTEX compounds in the soil and groundwater at the site In the process of the breakdown of the BTEX, hydroxyl radicals will be produced These hydroxyl radicals will then oxidize the longer chain gasoline range hydrocarbons and the oxygenated fuel compounds ' The end products of the BTEX and gasoline hydrocarbon oxidation are CO2 and water During the oxidation process, some of the original BTEX and gasoline will breakdown into ' intermediate compounds, alcohols and aldehydes These intermediate compounds will undergo oxidation to CO2 and water MTBE, and the other ethers, will oxidize to a series of daughter products, acetone being the last before ending in CO2 and water Acetone can continue to be oxidized by continued addition of peroxide and ozone, however, it is highly degradable by biologic organisms in the subsurface Bio attenuation will be enhanced by the addition of oxygen and ozone ' The pH of the groundwater in the center of the plume will be depressed slightly during the active treatment period This is caused by the breakdown of hydrocarbons to CO2 However, a combination of buffering from minerals in the aquifer and biological activity will act to raise pH to background levels