Sam Ziemann From - Region of Waterloo

HYDROGEOLOGICAL ASSESSMENTSTRANGE STREET WATER SUPPLY CLASS EA UPDATEREGIONAL MUNICIPALITY OF WATERLOOResults for Test WellMarch 19, 201220 L/s with each step lasting 30 minutes and no recovery between steps. Drawdowns of0.86 m, 1.76 m, 2.85 m and 4.07 m were observed at the end of each step. The specificcapacity was observed to decline with each increase in pumping rate (Table 3), decreasing from5.8 L/s per metre of available drawdown at a pumping rate of 5 L/s, to 4.9 L/s per metre ofavailable drawdown at a pumping rate of 20 L/s.4.6 CONSTANT RATE PUMPING TESTA 24 hour constant rate pumping test was completed at K-SS-TW1-11 to estimate potentialproduction rates from Aquifer 1 (AFB2).The test started immediately following the final step of the variable rate performance test onJune 13, 2011 at 14:20 at a pumping rate of 20 L/s. Groundwater levels were monitored atseven (7) locations during the pumping test, K-SS-OW1-82, K-SS-OW1A/B/C-11, K13,STOW2-07, and K-SS13-99 (Figure 1). All monitoring wells were screened within the pumpedaquifer (Aquifer 1) except for K-SS-OW1A-11 which was completed in Aquifer 2 (Table1).Figure 9 presents the hydrographs of monitoring wells that were monitored during the pumpingtest at K-SS-TW1-11, as well as pumping data for production wells in the Strange Street WellField.Weather conditions during the pumping test ranged from daily average temperatures of 13 o C to18 o C, with no precipitation events, according to observations recorded at the University ofWaterloo Weather Station located 5 km to the north of the site. The most recent precipitationevent occurred 6 days prior to the test and consisted of 4.5 mm of rain.During the pumping test, pumping rates from production wells within the well field remainedrelatively stable and therefore did not cause fluctuation of water levels within the aquifer(Figure 9). The only monitoring wells that were observed to respond to pumping from theStrange Street Well Field production wells were OW1-82 (Figure 9), which is located adjacent toProduction Well K10A, and to a lesser extent K13 and STOW2-07. These wells exhibiteddrawdown when K10A and K19 began pumping on June 7, 2011. During the constant ratepumping test, the only production wells that were in operation were K10A and K19, and none ofthe other monitoring wells appeared to respond to either of these production wells (Figure 9).All drawdown references presented in this section are relative to the water levels measuredprior to the start of the pumping test on June 13, 2011, which are interpreted to represent staticwater level conditions. The static water level data for each well is illustrated on Figure 9. Totaldrawdown observed at each monitoring location is also summarized on Table 1.hls v:\01609\active\161110897_strange_st\planning\report\final hydrogeo assessment\final\fnl_rpt_120319.docx 4.5