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PRE-CONSTRUCTION MONITORING RESULTS WOODBRIDGE NEIGHBORHOOD POROUS PAVEMENT PROJECT, SHOREVIEW POLYCYCLIC AROMATIC HYDROCARBONS (PAH) Due to a laboratory oversight, insufficient bottles were provided for the June event and polycyclic aromatic hydrocarbons (PAHs) could not be analyzed. PAHs were not detected above detection levels in the July sampling event. CHLORIDE AND BROMIDE Chloride concentrations detected in groundwater were higher than average for the Twin Cities metropolitan area, the Rochester area, and the St. Cloud area. According to the MDH (Potential for Groundwater Contamination by Road Salt in Minnesota, November 2008), the median chloride concentration for 1992-96 and 2004-05, respectively, were 4.9 and 12 milligrams per liter (mg/L). Bromide levels are also reported. The ratio between chloride and bromide has yet to be assessed to determine whether it indicates a road salt origin. The reported values are shown below: Monitoring well Date Compound Result (mg/L) Reporting Level (mg/L) National Secondary Drinking Water Standard m /L MW-1 June 25, 2009 Bromide - 0.0050 - MW-1 July 9, 2009 Bromide 0.0401 0.0050 - MW-1 June 25, 2009 Chloride - 0.500 250 MW-1 July 9, 2009 Chloride 23.0 0.500 250 MW-2 June 25, 2009 Bromide 0.0559 0.0050 - MW-2 July 9, 2009 Bromide 0.0248 0.0050 - MW-2 June 25, 2009 Chloride 49.9 0.500 250 MW-2 July 9, 2009 Chloride 29.0 0.500 250 MW-4 June 25, 2009 Bromide 0.0448 0.0050 - MW-4 July 9, 2009 Bromide 0.0472 0.0050 - MW-4 June 25, 2009 Chloride 25.8 0.500 250 MW-4 July 9, 2009 Chloride 28.2 0.500 250 It should be noted that the chloride levels from the June and July events are well above the median chloride concentrations referenced above but they are still far below the National Secondary Drinking Water Standard. The chloride concentrations should be watched for trends. TOTAL NITRATE+NITRITE NITROGEN Total Nitrate+Nitrite Nitrogen results are included in the attached tables. Concentrations are below the HRL.