Presented at the World of Coal Ash 2019 Conference—this paper presents the results of numerous simulations of various dewatering methods
By Peter Bell, Joel Thompson, and Don Fuller
Dewatering is a critical component of impoundment closure that supports site access, safety, settlement analysis and effective construction operations. The primary objective of ash dewatering is to modify the impoundment unit water budget such that flow out exceeds flow in, thereby lowering pore water saturation and transforming the project focus from water management to conventional earthwork. In this paper, we discuss how a finite difference three-dimensional numerical flow model (MODFLOW) can be used to evaluate dewatering methods under a range of hydrogeologic conditions and time frames. We present the results of numerous simulations of various dewatering methods to evaluate sensitivity to ash type, heterogeneity, timeframe, and interaction with groundwater. Model results are compared to real world case studies to provide a more complete understanding of dewatering approaches under various hydrogeological conditions and performance targets.
About the Authors
Peter Bell has over 14 years of experience as a hydrogeologist, he has expertise in groundwater flow modeling, light non-aqueous phase liquid (LNAPL) conceptual site models, capture zone evaluations and groundwater remediation.
Joel Thompson has worked with clients to provide key services such as; performance of groundwater flow and contaminant transport modeling, hydrogeologic investigation and model conceptualization, third party review, and statistical analysis of geologic, and groundwater chemistry data.
Don Fuller has over 25 years of experience. his areas of specialization include geotechnical, geoenvironmental and waste management and containment facility engineering as well as management of construction monitoring/quality assurance for related projects.