| Report Year: 2009 |
| Arbor Lake, Poweshiek County |
| Carbon Balance Table |
| Parameter | 6/15/2009 | 7/20/2009 | 2009 | 2008 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Alkalinity as CaCO3 (mg/L) | 156 | 147 | 151.5 | - | 130.1 | 144.7 | - | 123.0 | 92.3 | 95.7 | 132.3 | 128.0 |
| Dissolved Organic Carbon (mM) | 0.36 | 0.40 | 0.38 | - | 0.40 | 0.58 | - | 0.31 | 0.73 | 0.69 | - | - |
| Temperature (oC) | 20.2 | 24.2 | 22.2 | - | 26.6 | 25.9 | - | 22.8 | 25.0 | 25.4 | 22.9 | 24.4 |
| Specific Conductivity (μS/cm) | 550.0 | 490.0 | 520.00 | - | 465.34 | 606.26 | - | 450.53 | 478.69 | 401.54 | 455.80 | 349.72 |
| pH | 8.3 | 8.5 | 8.4 | - | 8.8 | 8.8 | - | 8.8 | 8.2 | 8.6 | 8.9 | 8.7 |
| I (Ionic Strength ?) | 0.0963 | 0.0858 | 0.0910 | - | 0.0814 | 0.1061 | - | 0.0788 | 0.0883 | 0.0608 | 0.0798 | 0.0612 |
| Dissolved Inorganic Carbon (mM) | 3.07 | 2.84 | 2.96 | - | 2.41 | 2.67 | - | 2.27 | 1.98 | 1.41 | 2.42 | 2.42 |
| pCO2 (μatm) | 650 | 366 | 507.8 | - | 196.4 | 174.1 | - | 178.9 | 628.7 | 200.8 | 190.3 | 200.1 |
| Equilibrium CO2 | 14.56 | 12.93 | 13.75 | - | 12.14 | 12.31 | - | 13.52 | 13.43 | 12.30 | 13.59 | 12.87 |
| CO2 (μM) | 25.59 | 12.78 | 19.18 | - | 6.30 | 5.74 | - | 6.26 | 21.36 | 6.98 | 7.75 | 6.88 |
| Δ CO2 from Equilibrium | 11.022 | -0.154 | 5.43 | - | -5.84 | -6.57 | - | -7.26 | 7.93 | -5.32 | -5.84 | -5.99 |