HIGHLIGHTS FOR 1999 



The Poplar River Power Station completed its sixteenth full year of operation in 1999. The two 300- 

 megawatt coal-fired units generated 4,185,100 gross megawatt hours of electricity. The average capacity 

 factors for Units No. 1 and 2 was 88.6 percent and 81.1 percent, respectively. The capacity factor is based 

 on the maximum generating rating of 305 MW/h for Unit #1, and 310 MW/h for Unit #2. Similar to other 

 years, scheduled maintenance was completed in the fall and spring of 1 999. 



Monitoring information collected in both Canada and the United States during 1 999 was exchanged in the 

 spring of 2000. In general, the sampling locations, frequency of collection, and parameters met the 

 requirements identified in the 1 999 Technical Monitoring Schedules set forth in the 1 998 annual report. 

 In 1999, the Committee also inifiated the Cookson Reservoir Study to investigate the potential salinity 

 problems associated with the Reservoir and its impact in the East Poplar River flows downstream. 



The recorded volume of the Poplar River at International Boundary from March 1 to May 31, 1999 was 

 35,440 dam^ (28, 730 acre-feet). Based on IJC recommendafions and the assumpfion that the recorded flow 

 is the natural flow, the United States was entitled to a minimum discharge on the East Poplar River of 0.085 

 cubic metres per second (m^/s) (3.0 cubic feet per second (ft^ /s)) for the period June 1 , 1 999 to August 3 1 , 

 1999 and 0.057 mVs (2.0 ft^ /s) for the period of September 1, 1999 to May 31, 2000. The minimum flow of 

 0.028 mVs ( 1 .0 ft^ /s) for the period January 1 to May 31,1 999 had previously been determined on the basis 

 of the Poplar River flow volume for March 1 to May 3 1 , 1998. Except for few days in July and August, daily 

 flows in 1999 met or exceeded the minimum flow recommended by the IJC. 



In addition to the minimum flow, the IJC apportionment recommendation entitles the United States to an on- 

 demand release to be delivered on the East Poplar River during the twelve-month period commencing June 

 1 . Based on the runoff volume of 4,420 dam^ (3,580 acre-feet) recorded at the Poplar River at International 

 Boundary gauging station for March 1 through May 31, 1998, the United States was entitled to an additional 

 release of 370 dam^ (300 acre-feet) from Cookson Reservoir during the succeeding twelve month period 

 commencing June 1, 1998. Montana requested this release to be made between May 1 and May 31, 1999. 

 A volume of 1 , 220 dam^ (989 acre-feet) was delivered during this period. 



The 1999 five-year total dissolved solids (TDS) flow- weighted concentrations were below the long-term 

 objective of 1 ,000 milligrams per litre (mg/L). The maximum monthly value calculated in 1 999 was just under 

 989 mg/L. The gradual increase in five-year flow-weighted concentrations for TDS is due to insufficient 

 surface runoff over the long term, which has not allowed for sufficient flushing of Cookson Reservoir. Boron 

 concentrations for 1999 continued to remain well below the long-term objective of 2.5 mg/L. 



