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27 October 2005 AGE-NC Project No. 96-0235 Page 2 of l 1 On 06 April 2005 Mc Campbell Analytical Inc. (MAI) was delivered five brass core tubes and 2 liters of unpreserved aquifer water,in addition to other preserved containers of aquifer water. The weight of the soil was determined to be 1.1 kilograms (kg), this allowed only one sample and one sample spike each consisting of 500 grams. A volume of 500 milliliters (ml)of aquifer water were used in each experiments. The soil was quickly manually homogenized and soil aliquots prepared for testing.Five experiment reaction vessels contained the sample and quality control/assurance were set up with and the remaining 5 vessels contained 500 ml de-ionized water for flow control purpose. The sample and QC/A vessels each contained 500g of soil and 500ml of aquifer water that were gently shaken for 30 minutes prior to purging. The QC/A sample spike vessels were treated like the sample except that it was spiked with 100 milligram (mg) of K2Cr2O7 which is equal 71 parts per million(ppm)of Cr". The blank was just 500m1 de-ionized water. QC/A spike contains 500ml de- ionized water and spiked with 100mg of K2Cr2O7 which is equal 71 ppm of Cr". Oxygen flow was initially set at 10 psi at the main regulator. Oxygen gas flowed to the ozone generator whose channel A and channel B were both set at 5 psi. The ozone flow from the ozone generator was directed to a glass splitter via Teflon tubing and then split into each vessel. The ozone gas exited from each vessel into an ozone scrubber that catalytically (no reactive chemicals) decomposed the 03. Purging continued for 5 days. All tubing and connections were Teflon or glass from the ozone generator to this point. The purge flow was monitored at the end of the scrubber outlet and tubing was restricted here to control the flow. The attached table demonstrates Ozone generating parameters. Experimental Measurements of Oxygen Head Pressure and Ozone Flow Time of Head Ozone Flow Measured at Scrubber Outlet (ml/min) Measurement Pressure Sample MS MB LCS LCSD Initial: 8 pm, 4/6/05 10lf 60 60 56 54 58 Day 1: 5 pm, 4/7/5 13 43 48 58 56 59 Day 2: 5 pm, 4/8/5 15 42 45 50 48 50 Da 5: 6 m 4/11/5 18 13 13 24 26 26 As reaction time progressed oxygen feed pressure nearly doubled but flows dropped two fold or more indicating that the system became"more restricted". This is easy to understand for the vessels that contained soil, but there is no definite explanation for those that contained only water. It is possible that condensed water in the ozone scrubbers is responsible. Comparison of this data with the ozone determinations shows that dissolved ozone concentration actually increases with lower flow rates, perhaps indicating that "self-purging" is significant. Dissolved ozone concentrations ranged from 0.029 - 0.066 milligram per liter(mg/L) and are tabulated in the results section. Advanced GeoEnviron mental,Inc.