A guest post by Hitesh Khant. Hitesh is an Earth Science student and a nature lover. His blog, Science Keeda, is about nature and natural processes.
There is a reason the earliest civilizations grew on the banks of rivers: Egypt along the Nile, Mesopotamia along the Tigris and Harappa along the Indus. Rivers make for convenient living; there is fresh water to drink, plenty of water to irrigate and channels to trade through.
But when rivers become dump yards for waste, this boon can quickly become a curse.
That is what happened along the Kali Nadi, Krishna and Hindon rivers in Uttar Pradesh, India. Thirty years of untreated wastewater discharge into the rivers made the water and the banks a dead zone—no fish, no trees, and plenty of disease for the villagers along its banks.
Investigations by a non-profit called Neer Foundation, the Central Pollution Control Board, the National Green Tribunal all found that the three rivers were facing the extreme level of industrial contamination. The contamination was not limited within the surface water but also spread to groundwater.
Groundwater from tubewells run yellow.
The contamination considerably affected districts like Muzaffarnagar, Shamli, Meerut, Baghpat, Ghaziabad and Gautam Budh Nagar as the areas depended on groundwater sources. In just one village near the Kali Nadi river, named Gognoli, 71 people died from cancer and 47 left bed-ridden.
Kali Nadi, named after Goddess Kali, has turned into Kali Nadi, or Black River.
The main culprits? Industries like sugar mills, distilleries, paper mills, electroplating and slaughter houses.
Industries, the main culprit
In the first post of this series, we saw how human wastes contaminate the groundwater. But this isn’t the biggest culprit. By far, the biggest culprit for groundwater contamination is industrial activity.
How do the factories of the country, the engines of our growth, threaten this reliable source of water for human populations? Today, we explore.
What kind of wastewater do industries release?
Industries use water for cooling, sanitation, manufacturing and processing. The used water comes out as an effluent, and depending on the use the water was put to, the properties of the effluent varies.
For example, if an industry uses water for cooling—like in automobile factories—it would make the water soft so that corrosion can be minimized. The effluent released has two types of pollutants: salts and heat. The impact of salts and thermal pollution on surface water is well documented, but salts can also affect soil salinity and leach into the groundwater. As this water percolates, its heat can alter the biophysical conditions of the soil and destroy many living organisms in the process.
Apart from effluents, stored water in underground tanks and pipes are another source of industrial groundwater contamination through leaks. The risk for this type of contamination is high in fracking sites, natural gas pipelines and nuclear waste disposal sites.
One of the many dangers of mining…
Mines and minespoils are one of the most extensively documented sources of groundwater pollution. The extent and type of pollution may differ depending on the type of mining and the ore that is mined—coal, phosphates and uranium are considered the most dangerous pollutants of groundwater—but excavation and chemical processing of any kind of mineral is bound to have some negative impact.
As the outflow of water from mines is generally acidic, the phenomenon is called acid mine drainage. Coal mines of North-East India, for example, commonly occur with sulphur, which under the right oxidation conditions can turn into sulphuric acid and drains into the groundwater, making it acidic.
This is what happened in Meghalaya…
In Meghalaya, famous for receiving the most rainfall in the world, unscientifically implementing a sub-surface mining technique called “rat-hole” mining has severely degraded the environment. In particular, acid mine drainage from fine coal particles and minespoils have polluted to groundwater.
Can industries prevent groundwater contamination?
Mitigation measures are specific to the industry, the form of activity and the concentration and type of pollutants in the effluent. It also depends on the location: industries near shallow groundwater areas or river banks are more likely to cause groundwater pollution, as we saw from the story of the Kali Nadi river.
Researchers and industry experts play a key role as advisors in this process. Take the acid mine discharge from Meghalaya’s coal mines. Researchers from India’s Center for Science and Industrial Research (CSIR) proposed three simple mitigation methods:
First, neutralize the acid effluents by adding alkaline chemicals before discharging the water. In test runs, trenches along the discharge paths were loaded with sodium bicarbonate (baking soda) and crushed limestone, which increased the pH of the effluent and made it almost harmless.
Second, introduce enzymes that can prevent microbes from oxidising the effluents into acids. Bactericides, anionic surfactants, alkyl benzene sulphonate and sodium lauryl sulphate proved effective in several tests.
Third, introduce physical barriers to cut off oxygen flow or prevent effluent movement. Without oxygen, there can be no oxidation and acid mine drainage. This can be done by submerging the minespoils under water. Minespoils can also be kept isolated from water flow, which prevents any form of leaching. Both these methods require a comprehensive water management plan in the mine.
The NGT took cognizance of the Kali Nadi river and groundwater pollution and immediately proposed several management and mitigation measures to restore the river.
- Multiple levels of monitoring by the State Pollution Control Board, local governance institutes and third-party verification of samples.
- Awareness generation among citizens and polluting industries.
- Manage sewage, industrial waste, solid waste and groundwater to ensure healthy water quality and quantity in the rivers.
Are there laws regulating industrial wastewater discharge?
Indian legislation has accounted for industrial sources of air and water pollution ever since the Bhopal Gas Tragedy of 1986. The Water Act 1972 and Air Act 1981, which preceded the Tragedy, have both specified measures for mitigating industrial pollution.
Under the ambit of the Water Act, 1972, Water Prevention and Control of Pollution Cess Act 1977, its amendment in 2003, as well as the overarching Environment Protection Act, 1986, the Central Pollution Control Board has devised effluent quality standards for different categories of industries in India, including their chemical composition and temperatures before being discharged into open water bodies. Many of these industries are required to treat their effluents in treatment plants on-site to achieve the prescribed standards before releasing it into natural water bodies.
Industries which violate these standards are required to pay a cess, which is like a tax that is used for restoration and remediation of water sources.
Can we completely avoid groundwater pollution by industries?
Groundwater is a prime source for drinking water for many in India. Thus, groundwater contamination creates several water-related risks in the country.
There has been greater political pressure towards better water management and sanitation by the current government, including the institution of the Jal Shakti Ministry to take care of source conservation and sewage management. This ministry will work in tandem with other relevant ministries like the Ministry of Environment, Forests and Climate Change and the Ministry of Commerce & Industry.
A lot of the regulatory issues stem from institutional corruption. Hopefully, the greater political will and scrutiny over water resources will prevent groundwater and surface water pollution by industries.
India is also taking the United Nations Sustainable Development Goals seriously, which has several targets addressing water security and sanitation.
Will these show positive results? Only time will tell. Until then, keep reading, asking questions and use your influence on social media to stimulate conversations. Support civil society organizations, environmental journalists and the NGT to continue to push for responsible effluent management. Trust me, we do not want “Kali Nadis” flowing underground.