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27 October 2005 AGE-NC Project No. 96-0235 Page 5 of 11 Major element Initial to Final values changed as follows. Ca from 91 to 35 ppm; Mg from 34 to 16 ppm; Na from 430 to 350 ppm; Al from 9600 to 850 parts per billion(ppb); Fe from 8800 to 900 ppb; Mn from 2500 to 390 ppb. Ca and Mg probably decreased due to carbonate pptn, Fe and Mn to oxide pptn. The Na and Al changes are harder to explain but may be substitution/exchange reactions for divalent Fe and Mn that are displaced from silicate lattices during their oxidation. The aquifer water already contained some anomalous trace amounts of heavy metals,including 39 ppb As, 1.3 ppb Be,9.7 ppb Cr,23 ppb Co, 1.7 ppb Cd, 100 ppb Cu, 1.2 ppb Mo,27 ppb Pb,36 ppb Ni, 1.9 ppb Se,35 ppb V,69 ppb Zn,in addition to 8800 ppb Fe and 2500 ppb Mn.It is not apparent why this natural water contains such high concentrations of heavy metals,although complexing with organic ligands may be important. The high concentrations of Fe and Mn are most likely the result of bacteria-mediated oxidation of hydrocarbons.By the end of the experiment almost all of these had diminished significantly, possibly by their sorption on Fe and Mn oxides, or as trace substitutions into silicates in exchange for Fe and Mn or as substitutions into precipitated carbonates. Two trace elements increased, Se from 1.9 to 15ppb and Mo from 1.2 to 48 ppb. Both could have been have been oxidized up from less soluble lower valence solids such as Se°,s or MOODS, or alternatively may have been mobilized by the decrease in Ca and Mg, if their Ca or Mg salts were at saturation. In the Final water, TRM total chrome was less than hexachrome, 3.2 vs. 8.4 ppb, but the TTLC hexachrome value of 9.2 was in much better agreement. The TTLC Final water metals values are also reported, and the common elements that form oxide/hydroxide solids, Fe, Mn and Al are significantly higher than their TRM values.Trace element comparisons range from good to slightly higher to erratic (significantly higher or lower), indicating that sampling and sub-sampling techniques are extremely important for metals. Soil The Initial and Final soil metals values were generally in good agreement after correction for water content.The only trace metal disagreements are Cu initial value=82 vs.final=47 mg/kg,Zn initial = 78 vs. final=67. For major elements, Ca initial= 5600 vs. final= 6300,and Na initial=980 vs. final = 1200, which is opposite and therefore in agreement with their decrease in concentration in the aquifer water. Advanced GeoEnvironmental,Inc.