| Abstract/Description or Keywords |
The Brucejack Property is situated within the Sulphurets District of the Iskut River region, approximately 20 kilometres northwest of Bowser Lake or 65 kilometres north-northwest of the town of Stewart, British Columbia. The present report documents surface water hydrology baseline studies completed for the project area. The objective of this study was to estimate key hydrologic parameters that characterize the hydrologic regime within the Project area for use in the environmental assessment as well as to assist in engineering design. In order to achieve this objective, Rescan established a hydrometric monitoring network and collected hydrometric data at streams, creeks, rivers, and lakes within the Project area during 2009 to 2012. This network evolved through the period of study as the scope of the Project changed. Hydrometric stations within the Project area that were used in this report include: o the outflow of Brucejack Lake that characterizes the local hydrologic regime at Mine Site; o three stations on Scott Creek, Todedada Creek, and Wildfire Creek watersheds that may be impacted by access roads; o a water level station in the Brucejack Lake; and o three hydrometric stations from a neighbouring project in Sulphurets-Unuk watersheds. The data set is particularly valuable since there are few hydrologic records from similar catchments from the Water Survey of Canada or elsewhere. This is especially true for watersheds less than 100 km2 in size. Monitored watersheds size, elevation, and glacierized coverage varied; as a result, different hydrologic regimes were seen in these watersheds. These include nival (Wildfire Creek), mixed (Brucejack Creek, Unuk River, Scott Creek, and Todedada Creek) and glacial (Sulphurets lake and Sulphurets Creek) regimes. Annual observed runoff values ranged from 1,188 mm at Wildfire-Hydro to 2,588 mm at Todedada-Hydro. Observed data within the Project area were supplemented by regional hydrologic analyses based on Water Survey of Canada Stations to estimate key hydrologic indices in the Project area. These indices include mean annual runoff, monthly distribution of runoff, and peak and low flows. Based on the regional analyses, mean annual runoff values in watersheds within the Project area were estimated as a function of the median elevation of the watershed. Peak and low flows were proved to be dependent on the drainage area of watersheds. |
