What Are Tailing Dams?

Tailing dams (Tailings Storage Facilities — TSFs) are engineered structures designed to contain the residual slurry produced during mineral processing. This material — crushed rock, water, and process chemicals — must be safely contained to prevent contamination of soil, groundwater, and surrounding ecosystems.

At HNC Green Projects, we design and construct tailing dams that go beyond minimum compliance — incorporating cutting-edge geotechnical engineering, environmental monitoring systems, and long-term stability planning into every project.

• Geotechnical investigation and site assessment for TSF location selection
• Structural design — upstream, downstream, and centreline dam construction methods
• Liner system design — HDPE geomembrane, compacted clay, composite liners
• Seepage collection and monitoring systems — underdrain networks, piezometers
• Decant and supernatant water management infrastructure
• Slope stability analysis and factor of safety modelling
• Environmental safeguards — dust suppression, vegetation cover, erosion control
• Regulatory compliance — MoEF clearances, State PCB consent, DGMS approvals
• Long-term closure planning and post-operational monitoring

Turning Liability Into Opportunity

India's mining sector generates millions of tonnes of tailings and waste rock annually. Modern analytical and processing technologies have revealed that these materials often contain significant concentrations of critical minerals — elements essential for EV batteries, renewable energy systems, electronics, and defence applications.

HNC Green Projects designs and implements processes to systematically characterise and extract critical minerals from waste stockpiles and active tailings streams, simultaneously reducing environmental liability and contributing to India's critical mineral security goals under the National Critical Mineral Mission.

• Lithium — Essential for Li-ion batteries in EVs and energy storage. Found in certain clay, brine, and spodumene tailings.
• Cobalt & Nickel — Critical for battery cathodes. Recovered from copper and laterite mining waste.
• Rare Earth Elements — Neodymium, dysprosium for magnets; cerium, lanthanum for catalysts. Found in phosphate and coal tailings.
• Copper & Zinc — Residual metals in flotation tailings from sulphide ore processing.
• Titanium & Zircon — Heavy mineral sands from coastal and alluvial mining waste.
• Manganese — Recovered from low-grade ores and heap leach residues.

• Tailings characterisation — XRF, ICP-MS, mineralogical assay
• Gravity separation — jigging, spirals, and shaking tables
• Froth flotation for sulphide mineral recovery
• Heap leaching and in-situ leaching for low-grade ores
• Hydrometallurgical processing — acid leach, solvent extraction, ion exchange
• Magnetic and electrostatic separation for REE and heavy mineral recovery

What is GGBS and Why Does It Matter?

Ground Granulated Blast-furnace Slag (GGBS) is a by-product of iron and steel manufacturing. When molten slag is rapidly quenched with water (granulation), it forms glass-like granules that, when finely ground, produce GGBS — a highly reactive cementitious material with exceptional properties.

Replacing Portland cement with GGBS reduces the CO₂ footprint of concrete by up to 80% per tonne, while improving durability, reducing permeability, and increasing resistance to sulphate attack. With India's steel industry producing millions of tonnes of slag annually, GGBS represents both an environmental solution and a significant commercial opportunity.

• CO₂ reduction of up to 800 kg per tonne of cement replaced — critical for net-zero construction targets
• Enhanced durability — lower permeability, better resistance to chloride ingress (marine/coastal applications)
• Reduced heat of hydration — ideal for mass concrete (foundations, dams)
• Higher long-term strength — GGBS continues gaining strength for years post-pour
• Reduced alkali-silica reaction (ASR) — extends structure life significantly
• IS 16714:2018 compliant — certified for all structural concrete applications in India
• Replacement rates of 35–70% of ordinary Portland cement in most applications

• Plant layout and civil works design for GGBS processing facility
• Granulation plant design — water granulation and pelletisation systems
• Vertical roller mill (VRM) and ball mill selection and installation
• Blaine fineness quality control systems (target: 400–500 m²/kg)
• Storage silo design, pneumatic conveying, and dispatch infrastructure
• BIS testing laboratory setup for IS 16714 certification
• Turnkey EPC — from raw slag intake to bagged/bulk product

Clean Water as a System Solution

Water is both a critical resource and a growing regulatory concern for India's industrial sector. Whether treating process water for reuse, remediating contaminated groundwater around mining sites, or providing potable water infrastructure for industrial townships, HNC Green Projects delivers water treatment systems that are robust, efficient, and compliant.

Our approach goes beyond filtration — we design systems for resource recovery, where treated water becomes an asset rather than a disposal burden, and where dissolved minerals in wastewater streams are extracted and monetised where technically feasible.

• Industrial Effluent Treatment Plants (ETP) — for mining, chemical, and manufacturing industries
• Sewage Treatment Plants (STP) — for industrial townships and communities
• Mine Water Treatment — neutralisation of acid mine drainage, heavy metal removal
• Reverse Osmosis (RO) systems — brackish water and TDS reduction for process water reuse
• Multi-stage filtration — sand, activated carbon, ultra-filtration membranes
• Tailing decant water treatment and recirculation — zero freshwater discharge systems
• Iron and manganese removal from groundwater for community water supply
• Fluoride removal systems — critical for industrial belts of MP, Rajasthan, and Telangana
• Zero Liquid Discharge (ZLD) systems for regulatory compliance in water-stressed areas