Sam Ziemann From - Region of Waterloo

HYDROGEOLOGICAL ASSESSMENTSTRANGE STREET WATER SUPPLY CLASS EA UPDATEREGIONAL MUNICIPALITY OF WATERLOOResults for Test WellMarch 19, 2012• Sodium concentrations ranged from 48 mg/L to 58 mg/L and exceeded the Medical Officerof Health Reporting (MOH) Limit of 20 mg/L but was well below the AO of 200 mg/L. Thisexceedance is only a potential concern for consumers on a low sodium diet;• Iron concentrations were steady at 2.1 mg/L in the samples collected on June 13 and 14,2011, and exceeded the AO of 0.3 mg/L. In comparison, iron concentrations at the otherStrange Street Well Field production wells are below the ODWS AO with the occasionaldetection exceeding the ODWS AO. The pumping test at K-SS-TW1-11 was a shortduration and concentrations of iron may decrease with increased pumping. The StrangeStreet Water Treatment Plant is being equipped to filter for iron and therefore elevated ironconcentrations does not represent a concern; and• Manganese concentrations ranged from 0.14 mg/L to 0.18 mg/L in the samples collected onJune 13 and 14, 2011 and exceeded the AO of 0.05 mg/L. The Strange Street WaterTreatment Plant is being equipped to filter for manganese and therefore elevatedmanganese concentration does not represent a concern.The sample collected at the end of the constant rate pumping test on June 14, 2011 was alsotested for microbiological parameters and VOCs. Total coliforms and Escherichia coli (e. coli.)were not detected. Heterotrophic plate counts were detected at 1 CFU/mL which is reflective ofbaseline conditions. There were no reportable detections of VOCs.The results of the groundwater samples collected at K-SS-TW1-11 at the start and end of thepumping test were similar. The groundwater is characterized as hard with relatively lowconcentrations of chloride, sodium, and nitrate and elevated concentrations of manganese andiron.hls v:\01609\active\161110897_strange_st\planning\report\final hydrogeo assessment\final\fnl_rpt_120319.docx 4.9