Soil samples were taken from areas of low pH (2.5-3.5) surrounding an outdoor coal storage pile. These samples were added to medium with naphthalene as the sole carbon source to enrich for organisms capable of degrading polycyclic aromatic hydrocarbons (PAH) at low pH. Five such bacterial strains were isolated. Sequencing of the 16S rDNA showed them to be members of the genera Clavibacter, Arthrobacter and Acidocella. These organisms were all capable of growth with naphthalene as a sole carbon source at low pH. The genes nahAc, nahAd, phnAc, nahH, xylE or GST, which are known to be associated with PAH degradation were not detected. Isolate 10, the Acidocella strain, tolerated high levels of mercury. PCR amplification and sequencing of genes from the mer operon from isolate 10 DNA suggested that mercury is transported into the bacterial cell and subsequently detoxified since the enzymes encoded by genes in this operon are involved in these processes.

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A bench‐scale treatability study was performed to evaluate the effectiveness of alkaline ozonation on removing per‐ and polyfluoroalkyl substances (PFAS) present in groundwater at a former industrial site in Michigan. The study involved testing the PFAS‐impacted groundwater under alkaline ozonating conditions under a range of experimental conditions, including modifying pH, hydrogen peroxide‐to‐ozone molar ratio doses, length of ozonation pretreatment times, and sampling techniques. PFAS‐spiked samples were used to determine if inorganic ions such as fluoride (F−), sulfate (SO42−), formate (HCOO−), acetate (CH3COO−), and trifluoroacetate (CF3COO−) were generated or if there were decreases in total organic fluorine resulting from PFAS treatment. The results from all tests indicate that decreases in PFAS concentrations were due to a combination of removal and destructive mechanisms with enhanced removal under acidic pH ozonation pretreatment conditions. Short‐chain PFAS concentrations increased during the experiments followed by an overall decrease in concentration under continuous alkaline ozonation conditions. Reductions in concentrations in perfluorooctane sulfonic acid of 75–97% were observed. Reductions in concentrations were also observed in other PFAS such as 6:2 FTS, PFHxS, PFOA, and PFNA. To our best knowledge, this is the first time that alkaline ozonation has been performed on PFAS‐impacted water while monitoring a larger suite of PFAS analytes in addition to destruction byproducts. Treatment of PFAS under the conditions discussed in this paper suggests that alkaline ozonation may be a viable remediation option for PFAS‐impacted waters.

Molecular analyses for the study of soil microbial communities often depend on the extraction of DNA directly from soils. These extractions are by no means trivial, being complicated by humic substances that are inhibitory to PCR and restriction enzymes or being too highly colored for blot hybridization protocols. Many different published protocols exist, but none have been found to be suitable enough to be generally accepted as a standard. Most direct extraction protocols start with relatively harsh cell breakage steps such as bead-beating and freeze-thaw cycles, followed by the addition of detergents and high salt buffers and/ or enzymic digestion with lysozyme and proteases. After typical organic extraction and alcohol precipitation, further purification is usually needed to remove inhibitory substances from the extract. The purification steps include size-exclusion chromatography, ion-exchange chromatography, silica gel spin columns, and cesium chloride gradients, among others. A direct DNA extraction protocol is described that has been shown to be effective in a wide variety of soil types. This protocol is experimentally compared to several published protocols.

Soil surrounding an outdoor coal storage pile is impacted by highly acidic leachate containing polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Soil samples were taken along transects radiating out from an outdoor coal storage pile and soil microcosms amended with 14C-labelled naphthalene were set up to assess the ability of organisms within this acidic soil to degrade PAHs. In the less acidic transect all soil samples were capable of naphthalene mineralization. In the more acidic transect, samples taken from points further away from the coal pile showed faster mineralization rates than samples taken from points close to the coal pile. Key words: coal pile, acidic soils, PAH degradation, naphthalene mineralization, soil microcosms.