The key objective of this research project is to develop a passive technology to treat military contaminants in active testing and training range surface runoff. This project will more fully characterize surface runoff from an active range to determine the typical contaminant profile. This will be coupled with evaluation of a variety of materials that have the potential to enhance the sorption and degradation of munitions constituents (MC) in surface runoff. Sorbents and reactive media to be evaluated will include both traditional biofilter materials such as peat moss, as well as more novel materials such as biochar, which has unique properties (e.g., high surface area, electron storage and shuttling capabilities) that may allow for more effective treatment of both legacy MC and newer insensitive high explosives (IHE). The sorbents will be combined with slow-release nutrient sources to stimulate abiotic and biological removal of the MC compounds. Bioaugmentation with known explosive degrading bacteria will also be evaluated. It is envisioned that materials evaluated during this project would be utilized as part of an integrated surface runoff control plan that operates passively (e.g., no energized infrastructure) and does not interfere with ongoing range activities. If successful, the technology will be both sustainable and compatible with ongoing range activities.

The technical objectives of this project will be achieved through initial field sampling combined with laboratory experiments conducted at multiple scales to identify, optimize, and provide proof-of-concept results demonstrating a passive treatment technology for the effective mitigation of a broad range of range runoff contaminants. The following specific technical tasks will be performed:

• Task 1. Characterize range surface runoff
• Task 2. Batch sorption/degradation experiments
• Task 3. Column sorption/degradation experiments and modeling

This project will concentrate on both legacy energetics (e.g., RDX, HMX, etc.), IHE (e.g., 2,4-dinitroanisole (DNAN), 3-nitro-1,2,4-triazol-5-one (NTO), and nitroguanidine (NQ)), and ionic energetics (e.g., perchlorate), as well as associated non-explosive compounds present in stormwater runoff (e.g., waxes, binders, plasticizers).

Contaminated surface runoff is an important concern, yet mitigation technologies for energetic compounds have not been sufficiently developed and widely deployed. In order to meet both operational range and habitat objectives, a low-impact, passive technology is required that can be emplaced within existing natural hydrologic features and is capable of treating explosive laden runoff in a reasonable timeframe. The technology in this project uses a passive biofilter treatment system to intercept stormwater runoff and lower dissolved and particulate loadings of MC and associated agents to larger receiving water bodies. An added benefit of such a system will be its ability to mitigate other potentially regulated parameters (e.g., total suspended solids (TSS), nitrate, etc.) (Anticipated Project Completion - 2024)

Fuller, M.E., E.M. Farquharson, P.C. Hedman, and P. Chiu. 2022. Removal of Munition Constituents in Stormwater Runoff: Screening of Native and Cationized Cellulosic Sorbents for Removal of Insensitive Munition Constituents NTO, DNAN, and NQ, and Legacy Munition Constituents HMX, RDX, TNT, and Perchlorate. Journal of Hazardous Materials, 424(C):127335. doi.org/10.1016/j.jhazmat.2021.127335.

Xin, D., J. Girón, M.E. Fuller, and P.C. Chiu. 2022. Abiotic Reduction of 3-Nitro-1,2,4-Triazol-5-One (NTO) and Other Munitions Constituents by Wood-Derived Biochar Through its Rechargeable Electron Storage Capacity. Environmental Science: Processes and Impacts, 24(2):316-329. doi.org/10.1039/D1EM00447F.