ARCHIVED REPORTS_XR0006121 - Laserfiche WebLink

Home Browse Search

[03 Consumed]soi, = change in 03 concentration in the presence of soil in mg/L V=volume of ozonated water in L M= mass of soil in g The ozone demand of the groundwater was estimated by adding 25 mL of IP groundwater to 0 975L of ozone-saturated water, then measuring the residual ozone concentration over time The GW ozone demand (GWOD.,) was taken to be the difference in ozone consumption in the presence and absence of GW It was calculated according to the Equation 6 The specific time pomt(s) used in the calculation are discussed in Section 30 GWODO,,= x[03 Consumed]GW— [03 Consumed]conmd x VtotNcw Eqn 6 where GWODoz = GW oxidant demand in mg 03 consumed/L GW [03 Consumed]c.0 l =change in 03 concentration in the absence of GW in mg/L [03 Consumed]Gw= change in 03 concentration in the presence of GW in mg/L Vtot=total volume of solution (ozonated water+ GW) in L VGW = volume of GW in L 2.3 Confirmation of Hydrocarbon Removal by Ozone and Peroxone A preliminary test was conducted in which a mixture of site soil and groundwater containing H2O2 were sparged with ozone to estimate the longevity of the H202 The presence of H2O2 was monitored using test strips In a test using 50 g COMP-7 soil, 500 mL IP groundwater, and 8 mL of 30% H2O2 (initial H202 concentration of 0 5%), the concentration of H202 was >1,000 ppm after sparging with 1% ozone for 3 hours To confirm that hydrocarbons were removed and to estimate the amount of removal due to destruction versus volatilization, three tests were conducted For each test, COMP-7 soil (200 g) and IP groundwater (2,000 mL) were placed in a closed reactor fitted with a gas dispersion tube and vent for off-gases To one of the reactors was added 33 mL of 30% H202, which gave an initial H202 concentration of 0 5% Deionized water was added to the other reactors so that the total volume was equivalent in all three reactors Two of the reactors, including the one to which H2O2 was added, were sparged with —1% ozone (in air) at a flowrate of 500 mUmin for 6 hours The third reactor was sparged with nitrogen at a flowrate of 250 rnUmm for the first 10 minutes, then 500 mL/minute for 5 hours 50 minutes All three reactors were stirred via a magnetic stirrer for the duration of the test Off-gases were collected in 40-LTedlar bags from 0-40 minutes and 40-80 minutes to detennme whether volatilization was occurring (Note that it was not feasible to collect all of the off-gases due to the large volume produced ) The off-gases PRIMA Environmental 6 Eva]of Peroxone June 1,2005 ETIGExxon#3942