This study develops a preliminary water balance for the Detour Lake open pit mine in northeastern Ontario, Canada, using only publicly available data. Water entering the pit was estimated from four sources: direct rainfall, surface runoff, spring snowmelt, and groundwater seepage. The groundwater component is drawn from a companion analytical study applying the Thiem radial flow equation to the same site. Under conservative bedrock conditions the system runs at an annual deficit of 0.263 Mm³/yr, manageable within the existing 3.5 Mm³ mine water pond. Under fracture-enhanced shear zone conditions, groundwater inflow alone generates a surplus of 27.2 Mm³/yr, an order of magnitude larger than pond capacity, confirming that shear zone hydraulic conductivity is the critical uncertainty for operational water management at this site. Seasonally, peak inflow occurs in April driven by snowmelt, delivering approximately 1.506 Mm³ in a single month. This study forms the second part of a three-paper analytical series on the Detour Lake site built entirely from publicly available data.
Isaiah Goodluck Ephraim (2026) studied this question.