Modeling of contaminant transport in subsurface environment in the vicinity of the landfill site in Ayutthaya, Thailand | |
| Author | Joshi, Smrita |
| Call Number | AIT Thesis no.WM-04-04 |
| Subject(s) | Water--Pollution--Thailand--Phra Nakhon Si Ayuthaya Waste disposal sites--Thailand--Phra Nakhon Si Ayuthaya Sanitary landfills--Thailand--Phra Nakhon Si Ayuthaya |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Safe and effective municipal waste disposal systems are amongst the serious challenges faced by many municipalities in Thailand. In the past decade considerable progress has been made to improve waste management practices. In many of the disposal sites environmental controls are established and efforts have been made to develop these areas as natural attenuation sites. The study aims to evaluate the long term impact of waste disposal facility on groundwater. The volume of water leaching from landfill is modeled as one dimension vertical flow system by HELP. A three dimensional contaminant transport model is developed to study the movement of contaminants from landfill to surrounding areas using MODFLOW and MT3D. The long term leachate generation rate from landfill is computed to be around five percent of the mean annual precipitation. Effects of field capacity of waste layer and cover soil in the leaching of leachate from landfill are analyzed. The hydraulic conductivity of the barrier soil is found to be most sensitive parameter affecting the percolation rate from landfill. The flow and contaminant transport model is calibrated by comparing the model results with the observed groundwater levels and measured concentrations of the contaminants in the four monitoring wells. Fifty years of simulation reveals that the concentration of contaminants could rise to higher values that allowable limits in the agricultural field surrounding the landfill. Spreading of contaminants is accelerated by the higher volume of leachate seeping from the landfill. The study reveals that lower values of lateral hydraulic conductivity of the top clay layer and higher values of vertical hydraulic conductivity of barrier soil facilitate the distribution of contaminants in the top layer. |
| Year | 2005 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Gupta, Ashim Das;Babel, Mukand Singh |
| Examination Committee(s) | Noppadol Phien-wej;Clemente, Roberto;Sutat Weesakul |
| Scholarship Donor(s) | Government of Denmark (DANIDA) |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2005 |