Experiences from Pilot- and Large-Scale Demonstration Sites from Across the Globe Including Combined Remedies with NZVI

Abstract

This chapter provides an overview of environmental restoration efforts involving the application of NZVI and NZVI composite materials. The chapter focuses on the novel application techniques aimed at improving the delivery, characterization and effectiveness of particles, drawing on direct field experience of the authors as well as review of over two decades of peer-reviewed literature. Stressing a base of knowledge through detailed site characterization towards a conceptual site model, this chapter’s main emphasis is on delivery techniques, options for particle formulation and challenges associated with different site conditions that would influence particle transport to the target contaminated areas, as well as monitoring requirements to evaluate treatment effectiveness. Particle types and injection characteristics are covered along with an evaluation of geological, hydrogeological, geochemical and microbiological conditions favourable for NZVI injection. The synergy between NZVI and bioremediation treatments is discussed along with observed changes in microbiological activity following particle treatments. This chapter also provides highlights of laboratory data needs, general permitting requirements and health and safety issues related to NZVI. The chapter concludes with a discussion of potential technology improvements that will likely improve the effectiveness and implementability of NZVI treatments.