Journals Proceedings

Abstract

The dump material consists of fly ash- slag- dolochar, accretion, drain dust which is highly alkaline, very loose and powdery, causing massive pollution to the surrounding. The run-off water was totally black, nearby vegetation was fully dust coated and always there was cloud of dust moving along the wind direction. The dump height was 35-40 m (in some places even 60 m), with steep slope (>70-80o), no space was available for regrading/terracing so that dump slope could be reduced. The total area of waste dump was 14 ha, which has to be ecologically restored. During technical restoration, 75-100 cm thick topsoil was spread and blanked with high tensile strength coir-mat. Once slope was blanketed with topsoil and coir-mat, grass-legume seed mixture was sown. Seed mixture was consist of both annual and perennial fast growing legumes, grasses and high biomass yielding annual shrubs. About 3o slope was given in the top of the dump to collect run-off, and developed community park and fruit orchards. Now part of the community park is being developed as “Helipad” because, landing surface is above the canopy height of tree. Average cost ecorestoration was US$ 11900 ha-1, out of which 41% contributed by excavation of transportation of topsoil, 23% for coir-mat and 16% was running cost of for heavy earth moving machinery. The study concluded that waste dump with loose steep slope can be restored by seeding with grass-legumes mixture blanketed with topsoil and coir-mat.