1. Groundwater Pollution Nanotechnology. Nanotechnology involves the manipulation and understanding of matter at the molecular or atomic level. Due to the small size of the particles, they exhibit very unique properties and behaviors when compared to lager scale particles of the same material. Advantages of Nanoscale Iron Particles (NIP)  Injectable directly into contaminated areas  Nontoxic (compared to other nanomaterials, including bimetallics)  High surface area  Well defined structure  Highly reactive-rapid degradation  Low NIP/contaminant ratios requirement  Both in-situ and ex-situ  Treatment is governed by iron corrosion reactions, lowers redox potential, generates hydrogen  Friendly to subsurface biomass  Chlorinated contaminant degradation is followed by the following mechanisms: Fe (0) → Fe 2+ + 2e - 2H 2 O → 2H+ + 2OH - 2H + + 2e - → H 2 (g) R-Cl + H+ + 2e - → R-H + Cl - C 2 HCl 3 + 3H + + 6e - → C 2 H 4 + 3Cl - NIP possess high reactivity with different contaminants (aqueous and soil systems). Increased NIP concentration increases the reactivity. Importance of Field Delivery Batch tests with sand initially spiked with DNT=740 mg/Kg  High Hamaker constant-i.e. attractive van der Waals forces  Chemical bonding  Hydrophobicity  Magnetic attraction (Fe0)  Settling due to their higher density  Attachment (sorption) of particles to soil surfaces The study investigated the reactivity during transport using horizontal column. We injected NIP slurry from one end and collected the effluent from the other end. The results show that lactate enhances the transport of NIP through the soil, but optimization of lactate and NIP concentrations is essential in order to ensure both adequate transport and reactivity of NIP. T=0 min. T=4 min. T=8 min T=13 min. Reactivity During Transport Conclusions & Recommendations  Lactate modification can minimize settlement and aggregation of NIP  Reactivity of NIP reduces with lactate-modification, but increases with time with or without lactate modification  Lactate modification is effective for maintaining the permeability (particularly at higher NIP dosages) and better transport of NIP in field sand  Lactate and NIP dosages and flow velocity should be optimized for effective delivery as well as reactivity for specific contaminant and soil type  Mathematical modeling and field pilot testing is in progress  Overall, our research has shown that nanotechnology has emerged as a viable option to reduce the contaminant levels in groundwater below the target risk-based levels. Global Solutions  Prevent groundwater contamination  Reduce nonpoint runoff  Reuse treated wastewater for irrigation  Practice four R's of resource use (refuse, reduce, recycle, reuse)  Reduce resource waste and air pollution  Reduce poverty and high birth rates Composition: α-Fe Core and Magnetite Shell Avg. Particle Size : 70 nm S.S.A. : 30Content m 2 /g Sulfur : 5,000 mg/kg NIP with 10% Aluminum Lactate Bare NIP Initial After pore volume # 12 Overall reactivity shows that 1g/L aluminum lactate enhanced the distribution of NIP, which resulted in the highest degradation of PCP. This shows that NIP can be effectively used to decontaminate polluted groundwater. Decontamination of Polluted Groundwater Using Nanotechnology Kenneth Darko-Kagya University of Illinois at Chicago (UIC) Department of Civil and Materials Engineering Performance of NIP for in-situ remediation is highly dependant upon its delivery to the point of need in the subsurface. Delivery of NIP can be done by injecting the slurry through drilled boreholes. The study investigated the transport of NIP using glass columns mounted vertically. The study found out that most of the bare NIP particles accumulated at the top of the soil after several flushing of electrolyte under pressure. The limited transport of the bare NIP was due to aggregation of the particles, which is a result of the following factors;  World population has increased 3x  Global water withdrawal has increased 7x  Per capita water withdrawal has increased 4x  Half of the world’s 500 rivers are heavily polluted  Up to 80% of Europe, Russia, Middle East and North America depend on Groundwater.  About 45% of the available fresh water is in a form of groundwater  Groundwater pollution is on the rise due to increase use of pesticides, fertilizers, synthetic organic compounds, solid waste disposal site.  Pollution can be due to point and non-point sources  About one-sixth of the world’s people don’t have easy access to safe water  80% of Diseases in developing countries are water related  Water pollution gets people sick and can kill Chemistry Despite the ability of the lactate to enhance the dispersivity of the particles. Its reactivity was reduced due to the surface coating. The difference in reactivity between NIP and LM-NIP was large initially but diminished after seven days. This can be due to the fact that aluminum lactate was protecting the NIP from easily getting oxidized or passivated. This indicates that aluminum lactate-modified NIP has a strong potential for remediation of soils contaminated with DNT in addition to enhanced transport in soils.