Guwahati: The Union government was assigned the task of defining the Aravalli range, one of the world’s oldest hill systems extending from the outskirts of Delhi to Gujarat across four States.
However, even after more than a year of deliberations by three expert committees using satellite data and inputs from various institutions, a uniform technical definition could not be finalised, prompting the process to continue following a Supreme Court warning of possible contempt proceedings against senior Environment Ministry officials.
A breakthrough came only after the Supreme Court warned that it could initiate contempt proceedings against senior officials of the Environment Ministry. Following this warning, a new sub-committee was formed in August 2025. Instead of clearly defining the Aravallis, the sub-committee focused on developing a definition that would “balance” environmental concerns with the Centre’s 2019 National Mineral Policy, which promotes mining of critical minerals for the “nation’s economic growth”. This was stated in a 2,000-page affidavit submitted by the Union Environment Ministry to the Supreme Court and reviewed by The Hindu.
Mining concerns
The final definition of the Aravalli range has triggered strong political and environmental reactions in recent days. Critics argue that the definition protects only hills above 100 metres, leaving most of the remaining hills open to mining and environmental damage. These unprotected areas form the bulk of the 700-km-long range that runs from Haryana to Gujarat, with most of it located in Rajasthan.
Amid criticism from environmental groups and widespread concern on social media that large parts of the Aravallis could be opened for mining, Environment Minister Bhupender Yadav said that no new mining licences would be issued until a comprehensive Management Plan for Sustainable Mining (MPSM) is prepared. The plan, to be drafted by the Indian Council of Forestry Research and Education, must follow the Supreme Court’s November 20, 2025 order. It will identify areas where mining is fully banned and zones where limited, strictly regulated mining may be allowed.
Need for a uniform definition
Illegal mining and the cutting of hill slopes in several areas had earlier led to petitions before the courts, prompting judicial intervention. To arrive at a uniform definition of the Aravalli hills, the Supreme Court set up a committee in 2024. The panel included representatives from the Environment Ministry, Forest Survey of India (FSI), State Forest Departments, Geological Survey of India, and the Supreme Court’s Central Empowered Committee.
The committee was asked to develop a scientific definition of the Aravallis that could be applied nationwide. After forming two sub-committees and facing criticism from the Supreme Court for delays, it finally submitted its report in October 2025. This led to the Supreme Court’s order on November 20, 2025.
Documents examined from the committee showed that the FSI had earlier defined the Aravalli hills in Rajasthan in 2010 using slope-based criteria rather than height. However, the committee was cautious to ensure that areas that were “not Aravalli” were not wrongly included.
“It is again reiterated that using only elevation and slope as criteria to demarcate the boundary of the Aravalli Hills and Ranges may lead to inclusion errors, as a significant part of Hilly area fall within the identified districts is non-Aravalli. In plain terms, not all areas of Aravalli have Hilly terrain and not all Hilly terrain in these 34 districts are necessarily Aravalli in terms of its Geological profile and extent,” the committee noted.
Slope and elevation
The first scientific attempt to formally define the Aravallis came in 2010, after the Supreme Court asked the FSI to map the range in Rajasthan. This followed a ban on mining in the State and petitions from mining companies claiming loss of livelihoods.
Under this Rajasthan-specific definition, hills with a slope greater than three degrees were classified as part of the Aravallis. The State’s average elevation of 115 metres was used, along with a 100-metre buffer on the downhill side to ensure slope stability. Flat land, plateaus, valleys, and depressions within this buffer were also included. However, the exercise did not specify how many hills were ultimately classified under this method.
Before this, ‘core’ hills were defined as elevated landforms with slopes of at least 30 degrees and a height difference of over 300 metres from surrounding land. Smaller hills near these core areas, with slopes above 17 degrees and within a 100 sq km area, were classified as ‘hill areas’.
Expert Panel Review
In 2024, a technical sub-committee led by the Director General of the FSI, with members from the Survey of India and the Geological Survey of India, began work on defining hills across the entire Aravalli range beyond Rajasthan.
For the first time, this effort used standard-resolution maps prepared by the Survey of India. Records show that even the FSI agreed that slope alone could not be the deciding factor.
“The Survey of India (SoI) and the Forest Survey of India (FSI) were not in agreement with the approach of hard… based solely on slope and local relief,” the committee report said. “They emphasised that other local and regional morphometric parameters may also need to be considered. Since the nature of Hills varies across different terrains, it may not be practical to apply uniform criteria of slope and relief across the entire region. This observation was further substantiated during the detailed slope and relief-based analysis carried out by the Technical Sub-Committee.”
Need for a Policy Resolution
The experts failed to reach a consensus even after holding six meetings between May and August 2025. The Supreme Court, on August 12, 2025, warned the committee that failure to submit recommendations could lead to contempt proceedings.
The court said that if “…recommendations were not submitted by the next date, the members of the Committee constituted in terms of our order dated 09th May, 2025, would be liable to be proceeded against for having committed Contempt of this Court…Basically, what is required to be done is to take a policy decision with regard to the definition of Aravali Hills and Ranges…we do not understand as to why a period of more than two months is required for arriving at a policy decision, which can be taken by the Secretary of the MoEF&CC by taking on board the representatives of all the State Governments…We are only interested in protecting the precious Aravali Hills and Ranges,” the order said.
Following this, the committee shifted focus to consulting States and framing a definition that would also allow sustainable mining. It noted that “…the Aravalli-Delhi system has been identified as having significant potential for critical minerals such as tin, graphite, molybdenum, niobium, nickel, lithium, and rare earth elements (REEs)…In this context, the Committee was of the considered opinion that while the ecological and environmental integrity of the Aravalli Hills and Ranges must remain the foremost priority, it is equally necessary to evolve a framework that enables systematic, scientific, and environmentally sustainable exploitation of critical, strategic, and atomic minerals located within the region. Such a balanced approach would ensure that the country’s strategic and developmental interests are not compromised.”
“The Committee after detailed deliberations felt that considering the wide variability of the elevation from Average Mean Sea Level (ASML) of Aravalli Hills and Ranges, the elevation with reference to local relief, as already being followed by Rajasthan and agreed to by other States, may be more appropriate and objective criteria for conservation and management of Aravalli Hills and Ranges,” the report added.