Wednesday, April 22, 2009: 2:00 p.m.
Agave Ballroom (Hilton Tucson El Conquistador Golf & Tennis Resort )
Groundwater is the most important drinking water source in many countries including Iran. Pump and treat method is one of the most conventional remediation techniques for both large-and small-scale groundwater cleanup. Numerical groundwater models coupled with optimization techniques can increase efficiency and reduce costs and operation time. The purpose is to determine how many wells to install, where these wells should be located and what pumping rate is required from each well, while the objectives of the design are satisfied at minimum cost.
Shiraz oil refinery was constructed in the 1970s.The groundwater table is shallow; therefore the aquifer is more prone to Petroleum contamination. Due to the shallowness of groundwater table, foundation of several underground facilities corroded faster than usual. The observations had revealed that the industrial activities contaminated the groundwater.
In this Remediation design process, initially the contaminant plume extent determined by field survey and mathematical models. The contamination information is obtained through observation wells and field sampling. After taking samples from monitoring wells, TPH (total petroleum hydrocarbons) of the samples were measured using Infracal TPH/TOG analyzer. Resulting concentration data are mapped and the concentration of sampled points is used to estimate the contaminant concentration at all unsampled nodes within the model.
In this case study a simulation-optimization approach was used. The MODFLOW and MT3D coupled with the GA were applied for determination of pumping rates and number and locations of pumping wells as decision variables. The objective of the optimization problem is to minimize the total pumping rate and maximize the total contaminant mass removed by pumping while satisfying the constraints.
The optimal design of the remediation system is a decision –making process. The final decision for designing optimal pump and treat system in scope of capture the pollution in this site is made from this design-revise-redesign process.
Shiraz oil refinery was constructed in the 1970s.The groundwater table is shallow; therefore the aquifer is more prone to Petroleum contamination. Due to the shallowness of groundwater table, foundation of several underground facilities corroded faster than usual. The observations had revealed that the industrial activities contaminated the groundwater.
In this Remediation design process, initially the contaminant plume extent determined by field survey and mathematical models. The contamination information is obtained through observation wells and field sampling. After taking samples from monitoring wells, TPH (total petroleum hydrocarbons) of the samples were measured using Infracal TPH/TOG analyzer. Resulting concentration data are mapped and the concentration of sampled points is used to estimate the contaminant concentration at all unsampled nodes within the model.
In this case study a simulation-optimization approach was used. The MODFLOW and MT3D coupled with the GA were applied for determination of pumping rates and number and locations of pumping wells as decision variables. The objective of the optimization problem is to minimize the total pumping rate and maximize the total contaminant mass removed by pumping while satisfying the constraints.
The optimal design of the remediation system is a decision –making process. The final decision for designing optimal pump and treat system in scope of capture the pollution in this site is made from this design-revise-redesign process.