On the scope and management of pesticide pollution of Swedish groundwater resources: The Scanian example

Twenty-three south-Swedish public supply wells were studied to assess pesticide pollution of regional groundwater resources. Relations between pesticide occurrence, hydrogeology, and land use were analyzed using Kohonen’s Self-Organizing Maps approach. Pesticides are demonstrated to be substantially present in regional groundwater, with detections in 18 wells. Concentrations above the drinking water threshold are confirmed for nine wells. Observations indicate considerable urban influence, and lagged effects of past, less restricted use. Modern, oxic waters from shallow, unconfined, unconsolidated or fracture-type bedrock aquifers appear particularly vulnerable. Least affected waters appear primarily associated with deeper wells, anoxic conditions, and more confined sediment aquifers lacking urban influence. Comprehensive, standardized monitoring of pesticides in groundwater need to be implemented nationwide to enable sound assessments of pollution status and trends, and to develop sound groundwater management plans in accordance with the Water Framework Directive. Further, existing water protection areas and associated regulations need to be reassessed.

[1]  K. Haarstad,et al.  Ten Years of Pesticide Monitoring in Norwegian Ground Water , 2007 .

[2]  A. van der Linden,et al.  Pesticides in groundwater and drinking water wells: overview of the situation in the Netherlands. , 2008, Water science and technology : a journal of the International Association on Water Pollution Research.

[3]  G. Destouni,et al.  General quantification of catchment-scale nutrient and pollutant transport through the subsurface to surface and coastal waters. , 2010, Environmental science & technology.

[4]  J. Olsson,et al.  Identification of typical synoptic patterns causing heavy rainfall in the rainy season in Japan by a Self-Organizing Map , 2007 .

[5]  N. Jarvis.  A review of non‐equilibrium water flow and solute transport in soil macropores: principles, controlling factors and consequences for water quality , 2007 .

[6]  M. Friedel,et al.  Data-driven modeling for groundwater exploration in fractured crystalline terrain, northeast Brazil , 2012, Hydrogeology Journal.

[7]  R. Gilliom.  Pesticides in U.S. streams and groundwater. , 2007, Environmental science & technology.

[8]  R. Gilliom,et al.  Occurrence of Pesticides in Shallow Groundwater of the United States: Initial Results from the National Water-Quality Assessment Program , 1998 .

[9]  G. Destouni,et al.  Small unmonitored near‐coastal catchment areas yielding large mass loading to the sea , 2008 .

[10]  W. Tappe,et al.  Diffuse atrazine pollution in German aquifers , 2004, Biodegradation.

[11]  M. Stute,et al.  A 3H/3He Study of Ground Water Flow in a Fractured Bedrock Aquifer , 1998 .

[12]  Kiran Bhowmick,et al.  Kohonen's Self-Organizing Feature Maps and Linear Vector Quantization: A Comparison , 2015 .

[13]  Jack Barbash,et al.  Pesticides in ground water: distribution, trends, and governing factors. , 1996 .

[14]  D. Saad,et al.  Linking ground-water age and chemistry data along flow paths: implications for trends and transformations of nitrate and pesticides. , 2007, Journal of contaminant hydrology.

[15]  P. Binning,et al.  Pesticides in water supply wells in Zealand, Denmark: a statistical analysis. , 2012, The Science of the total environment.

[16]  G. Destouni,et al.  Diffuse subsurface zinc loads from mining areas in the Dalälven River Basin, Sweden , 2009 .

[17]  N. H. Spliid,et al.  Evaluation of chloride and pesticide transport in a fractured clayey till using large undisturbed columns and numerical modeling , 1998 .

[18]  P. Cook,et al.  Dating of ‘young’ groundwaters using environmental tracers: advantages, applications, and research needs , 2010, Isotopes in environmental and health studies.

[19]  M. Close,et al.  Sixth national survey of pesticides in groundwater in New Zealand , 2008 .

[20]  Teuvo Kohonen,et al.  Self-Organizing Maps , 2010 .

[21]  A. M. Kalteh,et al.  Review of the self-organizing map (SOM) approach in water resources: Analysis, modelling and application , 2008, Environ. Model. Softw..

[22]  X. Morvan,et al.  Pesticides in the groundwater of a spring draining a sandy aquifer: temporal variability of concentrations and fluxes. , 2006, Journal of contaminant hydrology.

[23]  M. Rhein,et al.  The Bremen mass spectrometric facility for the measurement of helium isotopes, neon, and tritium in water , 2009, Isotopes in environmental and health studies.

[24]  J. Kreuger,et al.  Modelling pesticide transport in a shallow groundwater catchment using tritium and helium-3 data , 2014 .

[25]  Fraser.  A New Method for Data Integration and Integrated Data Interpretation : Self-Organising Maps , 2007 .

[26]  J. Kreuger,et al.  Multiresidue analysis of 95 pesticides at low nanogram/liter levels in surface waters using online preconcentration and high performance liquid chromatography/tandem mass spectrometry. , 2010, Journal of AOAC International.

[27]  E. Thurman,et al.  Pesticides in Near‐Surface Aquifers: An Assessment Using Highly Sensitive Analytical Methods and Tritium , 1995 .

[28]  D. K. Solomon,et al.  3H and 3He , 2000 .

[29]  H. Albrechtsen,et al.  Degradation of the herbicide dichlobenil and its metabolite BAM in soils and subsurface sediments. , 2007, Journal of contaminant hydrology.

[30]  Lisbeth Flindt Jørgensen,et al.  Groundwater monitoring in Denmark: characteristics, perspectives and comparison with other countries , 2009 .

[31]  R. B. Jackson,et al.  Water in a changing world , 2001 .