Sustainable management of debris disposal: Chamera Hydroelectric Project, stage-II

National Hydroelectric Power Corporation (NHPC) has recently constructed a 300 MW Chamera Hydroelectric Project (Stage-II) in Himachal Pradesh on river Ravi. At the planning stage initial environmental impact assessment was conducted and several environmental conservation and up-gradation plan was prepared, which also included debris utilization and disposal arrangements. NHPC believes in over all sustainable development and ensures systematic and realistic approach towards implementation of environmental programmes during construction of Hydropower Projects and side by side giving utmost importance towards maintaining ecological equilibrium of the surrounding environment. It is evident that during construction of any Hydropower projects a huge amount of muck (debris) is generated due to excavation of various underground components viz., Diversion tunnel, Dam body, Intakes, Head race tunnels, Desilting tunnels, Surge shaft, Pressure shaft, Power House and Tail race tunnel etc. The proper and systematic disposal of this muck requires utmost importance and care. During the planning phase of this project, a comprehensive and realistic muck disposal plan was prepared and the same has been implemented in true spirit during the entire construction period. Present paper details about the formulation of muck disposal scheme, arrangement for maximum uses and realistic implementation of disposal of surplus debris, alongwith construction works, in a sustainable manner. The project officers as well as Government and non-Governmental agencies ensured regular and strict monitoring during the entire construction period.

With adopting sustainable approach alongwith various construction activities, project management had very well managed the disposal aspect of excavated muck without disturbing the local environment of the project area. Out of the total muck excavated i.e., 17,18,200 cubic meter, the maximum part of it (11,13,200 cum) were utilized and reused in various activities like crushing of good quality muck, construction of coffer dams, land development works, wire-crates works, road development, etc. and balance muck (6,05,000 cum) was dumped at the 12 numbers earmarked sites. Protection walls on the down hillsides were constructed, along all these dumping sites, to avoid spilling over and pollute the river water.