Groundwater Impact Assessment
HGEC supports mines and quarries through the full asset lifecycle—greenfield, brownfield expansion, operations and closure. We characterise groundwater systems, prepare mine and quarry water balances, design and optimise dewatering, and deliver regulator-ready impact assessments that withstand scrutiny.
Greenfield (exploration and feasibility). We establish the baseline hydrogeological setting, define hydrostratigraphy and recharge–discharge pathways, identify receptors (springs, streams, neighboring users, GDEs), and quantify early inflow ranges to inform pit design and schedule. Preliminary water balances capture runoff, pit catch, seepage and groundwater make, providing inputs to cost, risk and approvals planning.
- Screening investigations and conceptual models aligned to approvals needs.
- Scoping dewatering concepts (perimeter wells, in-pit sumps/drains) with indicative inflow bands and seasonal variability.
- Baseline monitoring network design and approvals pathway mapping.
Brownfield (deepening and lateral extensions). We update the site water balance and inflow outlook, refine dewatering layouts (well spacing, screen intervals, duties) and address geotechnical depressurisation requirements where necessary.
- Incremental impact assessment: drawdown envelopes at boundaries/receptors, interference with third-party bores, stream/spring interaction risk.
- Mitigations such as grout curtains, cut-off trenches, recovery bores and managed discharge/return options.
Operational Support
We implement and tune dewatering systems for reliability and cost control, with telemetry/SCADA for performance tracking. Routine mine/quarry water balances reconcile abstraction, pit inflow, storm events, process demand and discharge limits to support planning and compliance.
- Duty/standby configurations, staged borefields and sump optimisation.
- Performance diagnostics (levels, rates, specific-capacity trends) and energy/cost optimisation.
- Compliance monitoring programs and concise licence reporting.
- Impact Assessment (regulator-ready). Our assessments present clear assumptions, auditable datasets and defensible methods. We address drawdown, take-and-use licence tests, cumulative effects across operations, and seepage pathways from TSFs and waste-rock landforms, with practical compliance points and monitoring designs.
- Mine closure and post-closure. We develop closure water strategies that anticipate rebound, pit-lake level and quality evolution, and residual seepage behaviour. Measurable closure criteria and adaptive monitoring transition sites from operational to custodial regimes while minimising perpetual obligations.
- Outcomes. Predictable inflows, right-sized dewatering, transparent water balances and defensible impact statements—supporting safer operations, lower whole-of-life cost and timely approvals through to relinquishment.
Why HGEC?
With more than 24 years of experience in hydrogeology and environmental consulting, HGEC delivers clear, practical, and scientifically defensible groundwater advice. Our independent approach ensures groundwater resources are protected while enabling clients to plan with confidence and certainty.
