Since the amendment notified on 29.03.2023, the need for groundwater modelling in a CGWA NOC application depends on four things: the type of project, the category of the assessment unit (block) where the site lies, whether the area is alluvial or hard rock, and the quantity of groundwater drawn.
Industry
- In over-exploited, critical and semi-critical units, hard rock areas need an analytical model above 100 m³/day and a numerical model above 500 m³/day.
- In the same units, alluvial areas need an analytical model above 100 m³/day and a numerical model above 1,000 m³/day.
- In safe units, a numerical model is needed above 500 m³/day in hard rock and above 2,000 m³/day in alluvium.
Mining
A numerical model is needed where mine seepage exceeds 500 m³/day (KLD).
Infrastructure
Any dewatering needs a numerical model, whatever the quantity.
What the model covers
The study area is normally a 5 km radius around the site. The report shows drawdown, radius of influence, impact on nearby wells and water bodies, and a water budget, prepared by an accredited consultant.
Check your project in the NOC checker
General guidance based on the CGWA guidelines and amendments in force when written. Rules change; we confirm the current position for your site before you apply.