19 



roughly six weeks while repairs were completed on the pipeline which transports water from the 

 salinity project wells to Cookson reservoir. As in previous years, the majority of the water was 

 pumped from wells PW87103 and PW87104 on the east side of the river and PW90108 on the 

 west side of the river. 



3.3.2 Ground-Water Monitoring 



3.3.2.1 Saskatchewan 



In 1996, 19 new piezometers were added to the monitoring network. Two of these were installed 

 in the Empress sands along the International Border and are included in the Soil Salinity Project 

 monitoring. Of the remaining piezometers, 7 were installed along the International Border. In 

 addition, 18 piezometers installed as part of the Frenchman aquifer ground water investigation 

 have been added to the monitoring program. 



There were no significant changes in the magnitude or shape of the cone of depression in the Hart 

 Coal seam in 1996 over previous years. The 1 metre drawdown contour is at or near the 

 International Boundary much as it has been for the past several years (Figure 3.11). The 

 reasonably consistent drawdowns over this time period (during which production volumes pumped 

 have been fairly consistent) implies that the aquifer system has approached a semi-equilibrium 

 state. Variations in the cone of depression appear to be primarily related to recharge and 

 variations in pimiping from the Hart coal seam. 



The goal of the Salinity Project is to lower the ground water levels in the Empress Sands (Figure 

 3.12) below Morrison Dam to approximately pre-reservoir levels. This is equivalent to roughly 

 2 to 3 metres of drawdown below the dam, and was achieved by the end of 1995. Water levels 

 recovered significantly in June 1996 when the production wells were not operated due to the 

 broken pipeline. Once normal pumping operations resumed the desired drawdowns were re- 

 established by the end of 1996. The magnitude and shape of the cone of depression has been 

 shown to be very sensitive to the operation of individual wells and local recharge in a given year. 



