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GEOSYNTEC CONSULTANTS <br /> Ms. Amy Terrell <br /> 25 August 2003 <br /> Page 7 <br /> Microcosms will be assembled under anoxic conditions in a disposable anaerobic <br /> glove box to ensure survival of any indigenous anaerobic microorganisms. The soil will <br /> be sieved thru a 12 nun sieve to remove large debris and to homogenize the soil. <br /> Triplicate sacrificial microcosms will be produced by filling 100 mL (nominal volume) <br /> pre-sterilized glass bottles with approximately 75 g of homogenized soil from the two <br /> cores that should represent an average of conditions found at the site. A nominal <br /> headspace may be retained for gas production (e.g., nitrogen, CO2i methane). The <br /> headspace of the bottles will be flushed with an inert gas (i.e. argon) so that nitrogen as <br /> production can be monitored. Soil pH and moisture content will be measured in the <br /> homogenized soil and the treatment bottles at time zero and completion of the study. <br /> Triplicate microcosms will be prepared so that sacrificial sampling can be done at a <br /> minimum of three time points (e.g. 0, 2 and 4 weeks), as well an additional set of <br /> triplicates for each treatment will be prepared for monitoring of nitrogen gas in the <br /> headspace. <br /> The intrinsic control microcosms (designed to measure intrinsic biodegradation <br /> activity) will not receive any amendments. Treatment microcosms will be amended <br /> with molasses/oil/other and HRC Primer. This will allow the assessment of the <br /> effectiveness of the different amendment additions. Microcosms will be sealed with <br /> Teflon lined caps that minimized gas exchange and moisture loss. MininertTM valves <br /> will be used on the additional set of bottles to allow repetitive sampling of each <br /> microcosm for nitrogen gas production. Incubation of the microcosms will be <br /> conducted in an anaerobic chamber(glove box). <br /> Task 3 - Microcosm Incubation, Sampling and Analysis <br /> After baseline characterization, samples will be collected from the control and <br /> treatment microcosms on a bi-weekly basis for analysis of nitrate, ammonia, and <br /> denitrification intermediates such as nitrite and nitrous oxide. Sample intervals for <br /> individual treatments may be modified (either shorter or longer intervals) during the <br /> study depending on observed microbial activity and degradation rates. At selected time <br /> points, samples will be collected for analysis of amendment consumption and organic <br /> carbon as an indication for the molasses microcosm treatments. All samples will be <br /> P:\PRJ2003REM\WFS\VER\Soil Plan 2003\RAP-Soil 8-25.doc <br />