Validation of stormwater biofilters using in-situ columns.

Stormwater harvesting biofilters need to be validated if the treatment is to be relied upon. Currently, full-scale challenge tests (FCTs), performed in the field, are required for their validation. This is impractical for stormwater biofilters because of their size and flow capacity. Hence, for these natural treatment systems, new tools are required as alternatives to FCT. This study describes a novel in-situ method that consists of a thin stainless steel column which can be inserted into constructed biofilters in a non-destructive manner. The in-situ columns (ISCs) were tested using a controlled field-scale biofilter where FCT is possible. Fluorescein was initially used for testing through a series of continuous applications. The results from the ISC were compared to FCT conducted under similar operational conditions. Excellent agreement was obtained for the series of continuous fluorescein experiments, demonstrating that the ISC was able to reproduce FCT results even after extended drying periods (Nash-Sutcliffe coefficient between the two data sets was 0.83-0.88), with similar plateaus, flush peaks, slopes and treatment capacities. The ISCs were then tested for three herbicides: atrazine, simazine and prometryn. While the ISC herbicide data and the FCT data typically matched well, some differences observed were linked to the different climatic conditions during the ISC (winter) and FCT tests (summer). The work showed that ISC is a promising tool to study the field performance of biofilters and could be a potential alternative to full scale challenge tests for validation of stormwater biofilters when taking into account the same inherent boundary conditions.

[1]  D. Mccarthy,et al.  Methodologies for Pre-Validation of Biofilters and Wetlands for Stormwater Treatment , 2015, PloS one.

[2]  D. Mccarthy,et al.  E. coli removal in laboratory scale stormwater biofilters: Influence of vegetation and submerged zone , 2014 .

[3]  B. Peake,et al.  Sources of heavy metals and polycyclic aromatic hydrocarbons in urban stormwater runoff. , 2006, The Science of the total environment.

[4]  D. White,et al.  In situ assessment of biodegradation potential using biotraps amended with 13C-labeled benzene or toluene. , 2005, Environmental science & technology.

[5]  Andrew J. Englande,et al.  Impact of urban stormwater runoff on estuarine environmental quality , 2005 .

[6]  G. W. Bailey,et al.  Soil-Pesticide Relationships, Adsorption and Desorption of Organic Pesticides by Soil Colloids, with Implications Concerning Pesticide Bioactivity , 1964 .

[7]  Ana Deletic,et al.  Variation among plant species in pollutant removal from stormwater in biofiltration systems. , 2008, Water research.

[8]  D. Mccarthy,et al.  The validation of stormwater biofilters for micropollutant removal using in situ challenge tests , 2014 .

[9]  A. Deletic,et al.  Nutrient and sediment removal by stormwater biofilters: a large-scale design optimisation study. , 2008, Water research.

[10]  D. Sabatini.  Sorption and Intraparticle Diffusion of Fluorescent Dyes with Consolidated Aquifer Media , 2000 .

[11]  Sylvie Barraud,et al.  Hydraulic performance of biofilter systems for stormwater management: Influences of design and operation , 2009 .

[12]  P. Smart,et al.  An evaluation of some fluorescent dyes for water tracing , 1977 .

[13]  Ana Deletic,et al.  Integrated treatment and recycling of stormwater: a review of Australian practice. , 2006, Journal of environmental management.

[14]  S. Toze,et al.  Decay of endocrine-disrupting chemicals in aerobic and anoxic groundwater. , 2008, Water research.

[15]  Shou-hong Zhang,et al.  Stormwater Capture Efficiency of Bioretention Systems , 2013, Water Resources Management.

[16]  Godecke-Tobias Blecken,et al.  Influence of intermittent wetting and drying conditions on heavy metal removal by stormwater biofilters. , 2009, Water research.

[17]  Z. Alach.  Australian drinking water guidelines , 2008 .

[18]  Hans-Jørgen Albrechtsen,et al.  In situ and laboratory studies on the fate of specific organic compounds in an anaerobic landfill leachate plume, 1. Experimental conditions and fate of phenolic compounds , 1995 .

[19]  R. Navia,et al.  Adsorption studies of the herbicide simazine in agricultural soils of the Aconcagua valley, central Chile. , 2009, Chemosphere.

[20]  Ana Deletic,et al.  Hydrologic and pollutant removal performance of stormwater biofiltration systems at the field scale , 2009 .

[21]  S. Weber,et al.  Assessment of in situ biodegradation of monochlorobenzene in contaminated groundwater treated in a constructed wetland. , 2007, Environmental Pollution.

[22]  D. Mccarthy,et al.  Evaluating Escherichia coli removal performance in stormwater biofilters: a preliminary modelling approach. , 2013, Water science and technology : a journal of the International Association on Water Pollution Research.

[23]  Günter Blöschl,et al.  Regionalisation of catchment model parameters , 2004 .

[24]  D. Mccarthy,et al.  Evaluating Escherichia coli removal performance in stormwater biofilters: a laboratory-scale study. , 2012, Water science and technology : a journal of the International Association on Water Pollution Research.

[25]  G. Merlin,et al.  Study of pyrene biodegradation capacity in two types of solid media. , 2007, The Science of the total environment.

[26]  J. Nash,et al.  River flow forecasting through conceptual models part I — A discussion of principles☆ , 1970 .

[27]  R. Govindaraju,et al.  Effect of geomorphologic resolution on modeling of runoff hydrograph and sedimentograph over small watersheds , 2003 .

[28]  G. Sposito,et al.  Mechanism of atrazine sorption by humic Acid: a spectroscopic study. , 1994, Environmental science & technology.

[29]  R. Moilleron,et al.  Priority pollutants in urban stormwater: part 1 - case of separate storm sewers. , 2012, Water research.

[30]  A Deletic,et al.  Is stormwater harvesting beneficial to urban waterway environmental flows? , 2007, Water science and technology : a journal of the International Association on Water Pollution Research.

[31]  R. Mandelbaum,et al.  In situ microcosms in aquifer bioremediation studies. , 1997, FEMS microbiology reviews.

[32]  Peter T. Zoller.  Composition and the Computer. , 1974 .

[33]  H. Richnow,et al.  In situ microcosms to evaluate natural attenuation potentials in contaminated aquifers , 2006 .

[34]  D. Mccarthy,et al.  Surrogates for herbicide removal in stormwater biofilters. , 2015, Water research.