|Scientific Closure of Gorai Dumpsite : First of its kind in country
Mumbai, spread over an area of 437.71 sq km with a population of more than 12 million people, generates around 6,500 tons per day (TPD) of Municipal Solid Waste (MSW) and 2,400 TPD of construction and demolition (C&D) waste. Characterized by high population densities, vast quantities of waste, large slum areas and proximity to sea coast with high humidity levels, and tidal inundation, Mumbai poses a unique challenge to the management of MSW.
The Gorai dumpsite is located in the western suburbs of Mumbai. It spreads over an area of 19.6 ha and is operational since 1972. The site is adjacent to Gorai creek and is very close to habitation. Approximately, about 2.34 million tons of waste up to an average height of 26 m is lying at the site.
The challenge in the context of Mumbai lies in developing scientific and environmentally compatible MSW processing and landfill facilities while keeping the site specific constraints in mind. To provide environmental solution for developing an Integrated Solid Waste Management Plan (ISWM) for the Metropolitan city, Municipal Corporation of Greater Mumbai (MCGM) has appointed IL&FS. The ISWM Project, which includes a comprehensive waste disposal plan, has been developed on a Public Private Partnership (PPP) framework. The Waste Management Plan is worked out as a set of independent but well synchronized projects, for each of the disposal sites at Gorai, Kanjur, Deonar and Mulund.
The Gorai closure project envisages converting about 19 hectares of land at Gorai dumping ground into green landscaped spaces for the Mumbai citizen. The existing practice of open dumping that has been followed since 1972 has caused significant environmental damage in neighborhoods adjoining the disposal site. The creek waters have been polluted due to inflow of leachate and the air quality has deteriorated from the frequent burning of garbage at the Gorai dumping ground.
As part of the scientific closure strategy, IL&FS recommended leveling and reforming the existing heap of MSW and incorporating environmental mitigation measures including laying of impermeable surface cover (Geo-textile/HDPE sheet), sheet piling to secure the site against tidal inundation, landfill gas (predominantly methane) collection and leachate collection system, development of a green belt and landscaping including a green cover over the dumpsite.
The capture and combustion of methane gas will result in a substantial reduction of greenhouse emissions and thus has the potential to earn carbon credits. Since IL&FS has pioneered the use of advance carbon financing to enhance sustainability of operations in several municipal waste management projects across the country, they were retained by the MCGM to provide CDM project advisory services in availing the CDM benefits for the project.
The Company was instrumental in getting an Advance Purchase Agreement signed with Asian Development Bank (ADB). As a result of this effort, MCGM has received an advance of Rs 250 million against future delivery of Carbon Credits from the Asia Carbon Fund of the ADB for the Gorai project. The transaction is one of the largest Carbon advance transactions in Clean Development Mechanism (CDM) in the world. It includes emission reduction to be generated from the project post-Kyoto protocol i.e. emissions in 2013-14 as well will get Rs. 250 million for the CER's sold until 2012. The Scientific Landfill Closure and Methane capture project at Gorai sets a benchmark in urban rejuvenation. The immediate benefits from the project are significant: the project has created 19 hectares of green space in Mumbai and led to the restoration of mangroves. Other environmental benefits include improvement in public health and hygiene; elimination of foul odour, fire and vermin nuisance, an improvement in the quality of creek water and an increase in avian fauna population. The project also demonstrates that the carbon credit finance mechanism can catalyze environmentally sustainable and financially viable closure of existing dumping sites and thus directly eliminating methane and replacing fossil fuel electricity generation to prevent GHG emissions in the atmosphere. The project provides a replicable role model for other municipalities.