Delivery and Mixing in the Subsurface

This volume is meant to provide the practitioner with information on the natural mixing processes occurring in aquifers as well as to describe basic strategies that can be implemented to enhance mixing in particular cases. For example, when it comes to mixing miscible liquids, one can speed up mixing in the formation by manipulating the flow such as through the use of recirculation wells. Furthermore, much of the mixing can be achieved partially within recirculation wells themselves, where contaminated water is admixed with additives, volatile products may be removed through a vapor mass exchanger, etc. Thus, adding mixing wells can significantly increase the performance of the delivery and mixing system and speed up the process of remediation. This volume describes the principles of chemical delivery and mixing systems and their design and implementation for effective in situ remediation. The intended audiences include the decision makers, practicing engineers and hydrogeologists who will select, design and operate remedial systems, as well as the researchers seeking to improve the current state of the science and technology. Our hope is that this volume will serve as a useful resource to assist remediation professionals in designing, applying and developing remedial technologies as effectively as possible.
Topics addressed in this volume include:
· An overview of the current state of understanding related to in situ chemical delivery and mixing, including a brief review of some of the remaining challenges and ongoing research.
· A tutorial on the reactions and processes of importance in groundwater remediation. Chapter 2 focuses on chemical and biological processes, while Chapter 3 focuses on transport and mixing.
· A discussion of available hydrogeochmicalmodeling approaches, including a detailed discussion of the travel-time approach to modeling. Protocols for practical implementation for design and monitoring of processes are included.
· Design issues and