Use of Sukhna's Silt as a Liner Material in Landfill

Sukhna lake of Chandigarh is roughly kidney shaped, located at 32? 42? N Lat. and 76? 54? E Long. With its concavity facing the Shiwalik Hills its northern boundary adjoining the Shiwalik Hills is natural and irregular and SW embankment, artificially built out of hewed stones, has a rock fill earth dam 12.8 m high. The lake is 1.52 km long and 1.49 km wide with initial storage capacity of 1, 074 ha-m of water. The catchment area of the choes feeding the lake have rugged terrain, steep slopes, plenty of gulleys, very deep-water table and the soils are predominantly alluvial sandy embedded with layers of clay which are highly susceptible to soil erosion by water run-off action. The impact of rain drops, quick flow of run-off and exposed soil coupled with hill denudation due to deforestation and animal grazing, are ideal conditions in the area for soil erosion. The water flowing into the lake is heavily loaded with silt. This silt deposited year after year in the lake bed reduces the water storage capacity, depth, water spread area and submergence area at lake level. [Source: Bansal and Grewal (1986, 1990) and CSWCR & TI (1993)]. From the previous researches it can be concluded that ? The average annual silt deposits are variable due to ineffectiveness of the measures taken as well as periodic differences in weather conditions. ? All this points to the fact that anti erosion and anti-siltation measures in the catchment area and Sukhna Lake respectively need to be taken simultaneously and on a continual basis. The aim of this paper is to explore and test the suitability of this silt mixture (with bentonite and flyash) as a liner material used in landfills.