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Dissolved organic matter (DOM) in surface waters used for drinking purposes can vary markedly in character dependent on their sources within catchments. The character of DOM further influences the formation of disinfection by products when precursor DOM present in drinking water reacts with chlorine during disinfection. Here we report the development of models that describe the formation potential of trihalomethanes (THMFP) dependent on the character of DOM in waters from discrete catchments with specific land-use and soil textures. DOM was characterized based on UV absorbance at 254 nm, apparent molecular weight and relative abundances of protein-like and humic-like compounds. DOM character and Br concentration (up to 0.5 mg/L) were used as variables in models (R(2)>0.93) of THMFP, which ranged from 19 to 649 μg/L. Chloroform concentration (12-594 μg/L) and relative abundance (27-99%) were first modeled (R(2)>0.85) and from these, the abundances of bromodichloromethane and chlorodibromomethane estimated using power and exponential functions, respectively (R(2)>0.98). From these, the abundance of bromoform is calculated. The proposed model may be used in risk assessment of catchment factors on formation of trihalomethanes in drinking water, in context of treatment efficiency for removal of organic matter., (Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.)

Application of winery wastewaters to soils for irrigation of various crops or landscapes is a common practice in the wine industry. In this study, we sought to investigate the effects of this practice, by comparing the physicochemical and microbiological soil properties in paired sites that differed in having had a history of winery waste application or not. We also compared the effects of a single application of untreated winery wastewater, to application of treated winery wastewater (sequencing batch reactor) and pure water to eliminate the effects of wetting alone. Long-term application of winery wastes was found to have significant impacts on soil microbial community structure, as determined by phospholipid fatty acid analysis, as well as on many physicochemical properties including pH, EC, and cation concentrations. (13)C NMR revealed only slight differences in the nature of the carbon present at each of the paired sites. A single application of untreated winery wastewater was shown to have significant impacts upon soil respiration, nitrogen cycling and microbial community structure, but the treated wastewater application showed no significant differences to wetting alone. Results are discussed in the context of sustainable winery wastewater disposal., (Copyright © 2011 Elsevier B.V. All rights reserved.)