- North Lakhimpur in Assam has treated a legacy waste of around 79,000 metric tonnes (MT) accumulated over 40 years in and near the river Sumdiri, which is not a designated dumping ground.
- The waste, cleared in less than a year, has been processed into Refuse-derived fuel, sent to be used as fuel in a cement factory, and to 25 mm and 6 mm organic matter used as fertiliser.
- Presently, waste segregation is being taken up as a pilot project in two wards where blue and green dustbins have been distributed for segregation. Awareness and training programmes are going on and the municipal board has procured collection vehicles for segregated waste.
Rajiv Mahanta reminisces about his childhood memories of fishing in the Sumdiri river, about 200-300 metres from his home in the North Lakhimpur district of Assam. He had not been able to fish here for around 20 years because of the accumulation of waste in the river.
This changed recently when the local authorities cleared a mountain of waste built up over the past 40 years in and near the river.
Manab Deka, the current MLA of Lakhimpur, who too has memories associated with the river, explains that the problem began in 1982-83 when the Municipality started dumping the daily garbage on land adjacent to the river. There was no opposition to it then. What started as a temporary measure continued to pile up over the years and eventually took over approximately four hectares of land, including the river.
According to the annual report 2020-21 of the Central Pollution Control Board, there were 3,075 dumpsites in India in 2021. Of these, 91 were reclaimed and 14 were converted into sanitary landfills. In 2020-21, India generated 1,50,847 tonnes per day (TPD), of which 52.88% was disposed of in dumpsites or remained unattended. Although interventions under the Swachh Bharat Mission have increased the quantity of waste treated yearly, a substantial amount remains unprocessed across the country.
Health and irreversible environmental hazards, ranging from greenhouse gas emissions, groundwater and surface water pollution, and air pollution, to surface fires are key concerns attached to dumping grounds. On this dumping ground in North Lakhimpur another associated characteristic of such sites was starkly evident – encroachment leading to disruptive and illegal activities such as selling illicitly distilled liquor and drugs, stealing and other alleged criminal activities.
“That jaborpatti (dumping ground) killed my husband. He got addicted to drinking and would spend the entire day with those anti-social people without going to work,” said Roshni Rajak (name changed) who lives in the area.
In such prevailing circumstances, the North Lakhimpur town of Assam has now processed over 40 years of legacy waste.
Battle with the legacy of waste
The North Lakhimpur Municipal Board (NLMB) was established in 1971. Then, in 1982-83, it started dumping garbage in Pub-Chandmari, on a large plot of land adjacent to the Sumdiri river, right in the heart of North Lakhimpur town, which has around 70,000 people.
“Having a small population then, no one thought the temporary dump would pile up into mountains of garbage in a few years. Probably that is why the most iconic temple of the town, the Shiva temple in the crematorium campus, a proud landmark of North Lakhimpur, was built just opposite the dump site in 1984,” said Pranjal Dutta, the Vice Chairman of NLMB.
When the Lakhimpur District Administration and MLA Deka decided to take up the task of clearing 40 years of legacy waste, the total amount of waste measured up to 79,000 metric tonnes (Mt) in December 2021.
In 2021, the absence of an elected municipal body (since the tenure of the last board was over in 2020 and the new board wasn’t elected until 2022), MLA Manab Deka and Lakhimpur Deputy Commissioner Sumit Sattawan initiated the process of cleaning about 40 years of legacy waste. The municipal body (then governed by the District Administration) floated an e-tender, and the job was allotted to a local company. Despite hindrances due to the monsoon rains for seven months (April to October 2021), the gamut of waste was cleared within nine months, by March 2023.
When team Mongabay- India visited the site, the legacy waste had completely been processed and the newly generated garbage of the town was now being treated in the same spot until the construction of a new solid waste management plant.
Casio Karan Pegu, Executive Officer of NLMB explained that the large mountains of municipal solid waste (MSW) were first excavated and broken into smaller piles, sprayed with an organic chemical called Bioculum, and left for 15 days to decompose. The decomposed waste was then passed through a Trommel machine comprising a cylindrical drum with several holes of predefined size that help segregate the waste material. It was used to obtain two by-products – 25 mm organic waste and the other Refuse-derived fuel (RDF), which is largely plastic. The 25 mm component is further processed through another Trommel machine, and the final product is six mm organic waste.
Part of the 25 mm and six mm organic waste is sold to farmers as fertilisers. The RDF is sent to a cement factory in the neighbouring state of Meghalaya to be used as fuel in the kilns. The NLMB so far does not derive a monetary benefit from this, instead transports truckloads of RDF at its own expense.
“The entire legacy waste has been converted to RDF and organic manure. Only about 20% has been cleared despite sending out truckloads weekly, but we are doing it vigorously,” said Pegu.
Following the clearance of the legacy waste, dredging is underway for clearing the river channel. Authorities expect the river to achieve its original status in the future. Though, they have not set any deadline to complete the dredging work.
The total expense for treating 79,000 Mt of legacy waste was Rs. 26.1 million, from the Tied funds of the North Lakhimpur Municipal Board.
Arundhuti Devi, associate professor at the Institute of Advanced Study in Science and Technology (IASST), appreciating the efforts, said, “The representative bodies have undertaken commendable work in clearing the dumping site of Pub-Chandmari, North Lakhimpur, within a short period of just nine months. The emergence of open refuse dumping sites occurs due to ceaseless unscientific increase in plastic consumption, untreated plastic waste disposal, illegal dumping near the river areas, and several other similar human activities leading to the piling of legacy waste.”
Responding to a query about RDF being sent to a cement factory, she added, “There is a need to recognise the chemical composition of the Refuse-derived fuel (RDF), which is largely plastic. Otherwise, its usage in the cement factory kilns of Meghalaya can pose certain environmental threats, which can be disadvantageous to the atmospheric, aquatic, and land ecosystems.”
The NLMB also sent the compost (the organic matter) produced as a by-product for a sample survey to the Pollution Control Board of Assam (PCBA). The results from PCBA show the presence of cadmium, copper, nickel, zinc, and chromium in the compost.
Analysing the PCBA report, Devi said, “The concentration of nickel in the enriched soil compost is below the permissible limits set by the World Health Organization (WHO), which is considered satisfactory. However, the levels of cadmium, chromium, copper, and zinc are higher than the recommended safe limits laid by WHO.”
Management of daily generated MSW
Presently, North Lakhimpur town generates about 36 to 42 tonnes of MSW per day. In the absence of a proper solid waste management (SWM) plant, the daily garbage is processed in the Trommel plant at the legacy waste site after being decomposed with chemicals. In lack of budget availability, the local administration has begun an awareness campaign to segregate the waste at source, from two local wards. If it is successful, the campaign will be implemented in other wards, says an official.
The District Administration has allotted around one-hectare plot far from residential areas within forest land. “The area has been selected following all guidelines of the National Green Tribunal in setting up an SWM plant. A tender will soon be floated for work in that plot,” said DC Sumit Sattawan.
The administration and the NLMB are also contemplating producing biogas from bio-waste and are in talks with Oil India Limited (OIL). “We will need about ten Mt of organic waste per day to generate ten Mt of biogas with a buyback policy by OIL. But our daily generation is less as of now,” said Deka.
NLMB has set up two wards as model wards, where blue and green dustbins have been distributed for segregation. Around 300 college students have been trained about segregating non-biodegradable and biodegradable waste and visit the houses weekly for awareness and training. The municipal board has also procured three segregated waste collection vehicles under Swachh Bharat Mission and is planning to procure another.
DC Sattawan said, “Presently, waste segregation is undertaken as a pilot project in two wards. Segregating at the source has the most financial benefit, as segregating at the SWM plant is highly expensive, especially for a small urban local body like Lakhimpur. However, we need to understand that these segregation practices need to be part of the habit among all citizens if it is to be successful. It will take many years. So, we plan to set up a new SWM plant where all waste can be processed together as we do not want to pile up legacy waste again. Meanwhile, awareness and education on segregation of waste will continue.”
The authority plans to convert the reclaimed area of around four hectares into a central ground in the model of Pragati Maidan, says Sumit Sattawan DC.
Read more: Untreated legacy waste is polluting the sensitive wetland ecosystem of Deepor Beel
Banner photo: A trommel machine comprising a cylindrical drum being used to clear the legacy waste in Lakhimpur, Assam. Photo by Surajit Sharma/Mongabay.