I have been attempting to understand coal-related issues for a few years now. For a meeting conducted recently, I was to prepare a brief note on our (Manthan’s) insights on some of the environmental impacts of coal-based electricity generation in India. I decided to share the note here, both to document the articulation of my understanding – anchored in the work that Manthan has done over the years – and to revive this blog with a post I believe could be useful for anyone interested in coal pollution in India.
The text of the note (with minor changes) is reproduced below.
Coal, Water, and Ash
The impacts of coal-based electricity generation on water are many. These can be seen at every stage of the coal cycle – from mining, washing, and transport of coal, to its burning in thermal power plants, and subsequent generation of coal ash. Listed here (in brief) are some insights on the same.
- Excessive Water Usage
Coal-fired thermal power plants (TPPs) require large amounts of water to operate, accounting for close to 70% of all water used for industrial purposes in India. Given this, TPPs can cause significant water stress in local areas, especially when present in clusters. For a detailed breakup of the various water uses by TPPs see this report by the Central Electricity Authority.

- Widespread Non – Compliance with Water Use Norms
– In December 2015, The Ministry of Environment, Forest and Climate Change (MoEFCC) introduced, for the first time, limits on how much water a plant can use per unit of electricity generated, i.e., ‘specific water consumption’ limits. Information obtained previously under the Right to Information Act (2005) revealed that despite legally binding limits and a two-year deadline to meet them, only about 51% of TPPs in the country were actually in compliance with the law.
– The same notification also introduced the mandate of ‘Zero Wastewater Discharge’ by TPPs, presumably in an attempt to mitigate some of the pollution impacts. Similar data revealed lax compliance, and information on compliance was scattered and inconsistent. The pollution control boards do not seem to have made complete monitoring information on these laws available in the public domain yet.
- Water Pollution, Depletion
– The operation of coal mines and washeries massively affects local ecosystems and communities. Negative impacts on the quantity and quality of important water sources have been documented across the country. Depletion of or falling groundwater levels, and drying of surface water sources due to dewatering effect of coal mines is common. Discharge of pollutants and wastewater streams from mines and washeries, and widespread coal dust cause water contamination
– From TPPs, contamination of surface and groundwater due to leaching and overflow of pollutants from ash ponds and ash dumps, and deliberate discharge of ash (slurry) into closest surface water systems has been common. Coal ash and coal dust also settles on domestic water storage containers, ponds etc.
– Disruption of surface water such as nalas or streams by ‘diversion’ for mines and plants is also common, often causing them to dry up completely
– In a study co-authored by Manthan (with Centre for Sustainable Development, Asar Social Impact Advisors Pvt. Ltd.) in November 2021, groundwater and surface water sampling in the vicinity of two state-owned TPPs in Maharashtra found that almost every water sample failed to pass Indian drinking water standards. It further found that the plants discharged effluents directly into local streams and rivers, and leakages from ash ponds all contaminated the surface and groundwater sources of the region. The presence of elements like antimony, aluminium, arsenic, boron, fluoride, iron, manganese, magnesium, mercury, molybdenum, lithium, lead and selenium was found at levels exceeding relevant water standards.

- Coal Ash Pollution, Mismanagement
– The coal ash (flyash and bottom ash) from TPPs also causes extensive country-wide pollution. It is known to contain toxic heavy metals, which pose threats to the health of people and the environment affected by them.
– In addition to its toxic nature, the quantities of coal ash generated by plants annually is colossal. The lack of adequate ash disposal and management infrastructure has meant several accidents with long term consequences are frequent. A report co-authored by Manthan (with Asar Social Impact Advisors Pvt. Ltd., Centre for Research on Energy and Clean Air on behalf of Flyash Watch Group) in July 2021 recorded the detailed status of eight coal ash accidents (ash pond breaches, deliberate discharge of ash into water bodies, pipeline leaks) that have occurred over the last two years. Subpar technical design and lackadaisical management of ash were found to be two important causes of the accidents. One such breach claimed six lives. Most of these accidents leave acres of farmland and homes covered in ash slurry, with delayed compensation and clean-up being the norm.
– Ash affects entities in proximity to power plants in more ways than accidents. Airbourne flyash settles on fields and homes, and due to its particle size is a respirable toxin linked with breathing and other health issues. It also settles on water bodies, rendering many sources unfit for use. Further, ash settles on standing crops posing threats to health and livelihoods of farmers and communities. The mixing of ash with water for transport for disposal is another route of exposure – leaky pipelines, and indiscriminate dumping of slurry in rivers and streams is frequent. The large-scale dumping of ash in ‘mounds’ or for “reclamation” of low-lying areas are some examples of how power plant and government authorities both allow unchecked pollution in the name of ash ‘utilisation’. The possibility of leaching of heavy metals from (often unlined) ash ponds and dumps into groundwater is also a concern.

- Flyash Utilization Notification (FAN), December 2021
The MoEFCC introduced the new FAN few months ago. It is the primary law pertaining to the roles and responsibilities for the management and utilization of ash. It also covers (rather inadequately) some of the environmental issues associated with ash. Though the notification introduces some positive additions, such as the mandate to utilize legacy ash, and the introduction of fines for defaulters, it fails to distinguish between ‘use’ and ‘disposal’ of ash, and provides loopholes for TPPs to avoid serious consequences in the way of fines/penalties. It also ambiguously categorizes several problematic uses of ash as ‘eco-friendly’, such as dumping in low-lying areas, thus providing the legal sanction for continued ash pollution. Detailed comments have been submitted by various groups (including Manthan) highlighting these and other issues with the new FAN.
- Notification, Guidelines for the use of Flyash in Abandoned Mine Voids, Low Lying Areas
In 2018 the MoEFCC introduced an OM pushing for the use of ash in abandoned coal mines and low-lying areas. It was introduced with guidelines issued by the Central Pollution Control Board detailing steps for the same, as well as a direction to allow the blanket reversal of all existing Environmental Clearance conditions presently prohibiting the use of ash via these two modes. An ongoing investigation by Manthan has revealed the lack of sufficient environmental safeguards, procedural gaps (of actual dumping of ash as well as obtaining clearances from authorities), possibly inadequate assessment of risks to environment from these modes, and other issues. These include but aren’t limited to – the potential for leaching of toxic heavy metals from ash-filled mine voids into groundwater, and the dumping of large quantities of ash in areas declared as ‘low-lying’ likely to contaminate soil and groundwater.
