Original EA Amendment

PHASE 2: MONTH 12 to 50

INFLOWS

OUTFLOWS

1752 ML/ann Dee River and Sludge

DOR WTP

1752 ML/ann

DOR WTP Transfer

1752 ML/ann

801 ML/ann

DOR WTP Transfer

430 ML/ann

Seepage Pumpback

Enhanced Evaporation

312 ML/ann

535 ML/ann

Rainfall and Runoff

Natural Evaporation

OCP

486 ML/ann Seepage Losses

3382 ML/ann

-793

Tailings Water to OCP

2870 ML/ann Return water to plant

785 ML/ann SSG to OCP Pumped Transfer

785 ML/ann SSG to OCP

3 ML/ann

Seepage Losses

583 ML/ann

23 ML/ann

Rainfall and Runoff

Natural Evaporation

SSGArea

219 ML/ann

0 ML/ann

Tailings Release 39 ML/period Basin 1&2 Spill

Spills to OCP

2870 ML/ann

3387 ML/ann

Return water to plant

Tailings Water to OCP

137 ML/ann Raw water from external source

377 ML/ann Ore Moisture

Process Plant

-2

NET SYSTEM BALANCE: -766

Figure A.2

Simulated mean forecast water balance for Phase 2 (OCP as the TSF)

12624987 | Heritage Minerals EA Amendment Application – Updates to Water Balance Model July 2025 (Final) 13