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Fly ash is a major component of solid material generated by the coal-fired thermal power plants. In India the total amount of fly ash produced per annum is around 100 million tonnes. Fly ash has a great potential for utilization in making industrial products such as cement, bricks as well as building materials, besides being used as a soil conditioner and a provider of micro nutrients in agriculture. However, given the large amount of fly ash that accumulate at thermal power plants, their possible reuse and dispersion and mobilization into the environment of the various elements depend on climate, soils, indigenous vegetation and agriculture practices. Fly ash use in agriculture improved various physico-chemical properties of soil, particularly the water holding capacity, porosity and available plant nutrients. However it is generally apprehended that the application of large quantity of fly ash in fields may affect the plant growth and soil texture. Hence there is a need to characterize trace elements of fly ash. The results of trace element analysis of fly ash and pond ash samples collected from major thermal power plants of India by Particle Induced X-ray Emission (PIXE) have been discussed.

In this study, liquefaction and earthquake response analysis of Panipat pond ash embankment in India has been carried out considering saturated and natural water table conditions. Laboratory and field studies have been carried out to obtain the material properties required for the nonlinear response analysis of the Panipat pond ash embankment. Nonlinear finite element analysis has been carried out by using open system for earthquake engineering simulation (OpenSees). Three earthquakes namely Chamba, Chamoli and Uttarkashi earthquakes have been considered for liquefaction and earthquake response analysis. The standard penetration test (SPT)-$N$ value indicates that the ash deposit in Panipat pond ash embankment is in loose to medium dense state. The excess pore pressure ratio obtained from the analysis is found to be one or more than one below upstream and downstream locations of the pond ash embankment for both saturated and natural water table conditions. The horizontal and vertical displacement is found to be maximum near the toe and first rise slope of pond ash embankment. Hence, ash embankment in Panipat is prone to liquefaction under the excitation of moderate to high earthquake loading.

Pond ash is a suitable embankment material for the construction of road. However, this material is not in practice for the construction of railway embankment in India. Very limited basic study is available in the literature. Due to this, study the behavior of pond ash railway embankment under dynamic condition, a pilot project on 'Design of pond ash railway embankment' is carried out by Central Road Research Institute, New Delhi, India. Pond ash was collected from National Thermal Power, Kahalgaon, Bihar, India. In this paper, geotechnical properties of pond ash and local soil are presented. Design and stability analysis of embankment with different height (with or without berm) is carried out considering the uniformly distributed load due to train loading under the water logged and sudden drawdown conditions with earthquake factor. It was observed that critical factor of safety was found for lower height of embankment in comparison to the higher embankment.