Public Relations

1. Waste-Management Education and Research Consortium In-Situ Remediation of TNT and RDX Contaminated Soil Using Zero Valent Iron and Spinach Extract Task 8 Chris Michel, David Ladner, Sara Lubchenco, Jeremy Seibert 2002 Design Contest Problem Summary A 6070 ha site has been used for military training for several decades and is now a CERCLA site due to low levels of contamination from RDX, HMX, and TNT explosives found in the soil. The site lies directly over a major groundwater recharge area. It is the job of NMT design team to develop a technique for remediating the soil to prevent potential contamination of the local aquifer. Economic Analysis A Monte Carlo simulation was performed to analyze project costs using assumed parameter distributions. The results are as follows. Note that the histogram below applies only for treatment of 7650 m3 of soil. RDX and TNT Degradation Results • Selected Remediation Method • The NMT design team chose a two-phase in-situ remediation process that will ultimately prepare the site for use as a wildlife refuge. • First Phase (0-1 yr) - Multiple applications as needed with • - Zero Valent Iron (ZVI) • - Spinach ( Spinacia aoleracea) Extract • Second Phase (1-5 yr) - Phytoremediation using • -Switch grass (Panicum virgatom) to passively remediate residual energetics to below regulatory standards • Rules and Regulations • In any environmental design it is of the utmost importance to consider human health and safety as well as impact to the environment. The proposed remedial process is governed by a variety of regulations, such as • Workers Health and Safety-OSHA (29 CFR 1910) • UXO-RCRA Military Munitions Rule (40 CFR 260) • Remediation Process Selection-CERCLA (40 CFR 300) • Endangered Species Protection and Permit-ESA (50 CFR 251) • Phytoremediation Plan-Phytotechnology Regulatory and Guidance Document (Interstate Technology Regulatory Counsel ) RDX Degradation with ZVI and Spinach • Full Scale Implementation • A full scale implementation of the technology has been designed to treat 7650 m3 of contaminated soil. The timeline for this design is as follows: • Clearing and preparation of the site • Subsequent soil testing to develop a concentration contour plot of contamination • Treatment of the area with the first applications of ZVI and spinach extract • Subsequent treatment of energetic hot spots, as identified by the concentration contour plot, with additional applications according to soil concentration • Re-vegetation of the site with switch grass as part of a wildlife seed mixture • Post-closure monitoring in accordance with applicable regulations Public Relations Maintaining proactive public relations is important to the NMT design team. Community forums will be held to inform the public about the remediation process. All of the data collected will be made public and follow-up meetings will be held to ensure community-right-to-know and to facilitate a basic understanding of the ramifications of this project. Results The results of various degradation experiments are displayed to the right. Dimensionless concentration versus time plots show a first-order degradation. The rate constants for each degradation curve are as follows. • References • Palazzo, A. et al. Rehabilitation of Sandy Soils in Cold Regions <http://www.army-itam.com/workshop/5wkshp/abstractbook/palazzo.htm> • Riefler, R. and Smets, B. (2000) Enzymatic Reduction of 2,4,6-TNT and Related Nitroarenes: Kinetics Linked to One-Electron Redox PotentialsEnvironmental Science and Technology. 34:3900-3905. • Schnoor, J. et al. (1995) Phytoremediation of Organic Nutrient Contaminants. Environmental Science and Technology. 28, 318A-323A. • Singh, J. et al. (1998) Remediating RDX-Contaminated Water and Soil Using Zero-Valent Iron. J. Environmental Quality. 27:1240-1245. HPLC Chromatograph