Brooks J. Devary

Treatability Study of In Situ Technologies for Remediation of Hexavalent Chromium in Groundwater at the Puchack Well Field Superfund Site, New Jersey

This treatability study was conducted by Pacific Northwest National Laboratory (PNNL), at the request of the U. S. Environmental Protection Agency (EPA) Region 2, to evaluate the feasibility of using in situ treatment technologies for chromate reduction and immobilization at the Puchack Well Field Superfund Site in Pennsauken Township, New Jersey. In addition to in situ reductive treatments, which included the evaluation of both abiotic and biotic reduction of Puchack aquifer sediments, natural attenuation mechanisms were evaluated (i.e., chromate adsorption and reduction). Chromate exhibited typical anionic adsorption behavior, with greater adsorption at lower pH, at lower chromate concentration, and at lower concentrations of other competing anions. In particular, sulfate (at 50 mg/L) suppressed chromate adsorption by up to 50%. Chromate adsorption was not influenced by inorganic colloids.

Electrospray Ionization Mass Spectrometry of Hexanitrohexaazaisowurtzitane (CL‐20)

Abstract Hexanitrohexaazaisowurzitane (CL‐20) is a newly developed propellant and has been examined using negative ion electrospray mass spectrometry. The primary ions observed included adduct ions (M+Cl)– and (M+ONO2)−.

In Situ Degradation and Remediation of Energetics TNT, RDX, HMX, and CL-20 and a Byproduct NDMA in the Sub-Surface Environment

Energetics such as RDX, HMX, and CL-20 exhibit low sorption and natural degradation, resulting in widespread groundwater contamination. Alternatively, TNT exhibits strong sorption and degrades to toxic recalcitrant intermediates. Field scale abiotic, biotic, and coupled abiotic/bioremediation can be more cost effective than pump and treat or sediment removal, but rates of processes in relevant insitu conditions need to be understood.