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APTIM Authors/Contributors Tomas Perina, Project Manager, Environmental Services Abstract A new solution for advective–dispersive solute transport is developed for three-dimensional aquifer of finite thickness and width, infinite extent along the direction of flow, dual porosity, equilibrium linear sorption and first-order decay of both the sorbed and dissolved mass with coefficients…

APTIM Authors/Contributors Background/Objectives Sediment resources are essential to fulfill the State of Louisiana’s commitment to implement a Coastal Master Plan (CMP) to mitigate its chronic land loss, protect more than 2 million people who live in the coastal zone, and to save Louisiana’s rapidly disappearing complex and fragile ecosystem. With…

APTIM Authors/Contributors Mark E. Fuller, Senior Research Scientist, Biotechnology Development and Applications Group (BDAG) Abstract The environmental fate of 3-nitro-1,2,4-triazol-5-one (NTO) and other insensitive munitions constituents (MCs) is of significant concern due to their high water solubility and mobility relative to legacy MCs. Plant-based biochars have been shown to possess…

APTIM Authors/Contributors Background / Objectives This study contrasts the use of high-resolution passive sampling and traditional groundwater monitoring wells (GWMW) to characterize a chlorinated solvent site and assess the effectiveness of a biowall (mulch, compost and sand) that was installed to remediate trichloroethene (TCE), the primary contaminant of concern. High-resolution…

APTIM Authors/Contributors Background/Objectives This paper describes an offline low-temperature derivatization method combined with gas chromatography-isotope ratio mass spectrometry (GC-IRMS) to enable compound-specific isotope analysis (CSIA) of C and N in the explosive compound 3-nitro-1,2,4-triazole-5-one (NTO). NTO is being used widely as a component of insensitive munition (IM) composites such as…

APTIM Authors/Contributors Paul Hatzinger, Director of Biotechnology Development and Applications Group Background/Objectives Natural perchlorate (ClO4−) exists in many places on Earth, in lunar regolith, meteorites, and on the surface of Mars. Terrestrial natural ClO4− has widely variable Cl and O stable isotopic compositions (δ37Cl, δ18O, Δ17O). The δ18O and Δ17O values…

APTIM Authors/Contributors Background/Objectives Compound-specific isotope analysis (CSIA), position-specific isotope analysis (PSIA), and computational modeling (e.g., quantum mechanical models; reactive-transport models) are increasingly being used to monitor and predict biotic and abiotic transformations of organic contaminants in the field. However, identifying the isotope effect(s) associated with a specific transformation remains challenging…

Full Title: 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. APTIM Authors/Contributors Abstract Technologies are needed to address contamination with energetic compounds at military installations.…

APTIM Authors/Contributors Background/Objectives Natural chlorate (ClO3−) is widely distributed in terrestrial and extraterrestrial environments. To improve understanding of the origins and distribution of ClO3−, we developed and tested methods to determine the multi-dimensional isotopic compositions (δ18O, Δ17O, δ37Cl, 36Cl/Cl) of ClO3− and then applied the methods to samples of natural nitrate-rich caliche-type salt deposits in…

APTIM Authors/Contributors Background/Objectives In surface water environments, photodegradation may be an important process for the natural attenuation of 2,4-dinitroanisole (DNAN). Understanding the photolysis and photocatalysis mechanisms of DNAN is difficult because the photosensitivity of nitro groups and the behavior of DNAN as a potential photosensitizer are unclear in aqueous solutions.…