Eivind Solbakken

Lead Engineer

(+47) 902 31 373
eivind.solbakken@nibio.no

Place
Ås R9

Visiting address
Raveien 9, 1430 Ås

To document

Abstract

The study examines the influence of agricultural activities on pesticides in groundwater in an area with fluvial deposits of sand with a top layer of sandy silt and silt, intensive cultivation of potatoes and cereals, and drinking water supplies of households from local groundwater wells. Information about local agricultural practice and washing sites for pesticide spraying equipment, properties of soils and deeper deposits, hydrogeology and groundwater flow, simulations of pesticide leaching, and contents of pesticides and nitrate in groundwater samples from drinking water wells was used to explore extension and reasons of pesticide contamination of groundwater. Pesticides were found in a majority of the sampled wells. Eight different pesticides and metabolites were detected in groundwater samples. The results demonstrate that on fluvial deposits diffuse pollution from spraying of fields with pesticides can result in groundwater contamination in Nordic climate. Higher concentrations of pesticides in some wells can be explained by point source contamination from washing sites. The occurrence of pesticides in drinking water wells touches up the question whether pesticides should be given general approvals, or approvals should include restrictions or recommendations regarding use on areas with high risk of groundwater contamination. Combination of washing sites for pesticide spraying equipment and groundwater wells for drinking water requires attention, proper equipment and practice, and knowledge about pesticides, soil and water to avoid contamination. Samples from wells adjacent to washing sites for pesticide equipment might overestimate average pesticide concentrations in groundwater bodies. In Nordic areas attention should be given to pesticide pollution of shallow groundwater in fluvial deposits. To provide basis for interpretation of results and planning of mitigation measures against pesticide contamination, an integrated approach using information about agronomical practice and point sources, soil properties, hydrogeology and simulations of pesticide leaching is recommended for future surveys and monitoring of pesticides in groundwater.

Abstract

Soil, composed of minerals, organic material, air and water, performs a number of key environmental, social and economic services that are vital to life. Supplying water and nutrients to plants while at the same time protecting water supplies by storing, bufferingand transforming pollutants. Soil is also an incredible habitat that provides raw materials, preserves our history and limits floods. Without soil, the planet as we know it would not function. However, the importance of soil and the multitude of environmental services that depend on soil properties are not widely understood by society at large. Soil scientists are becoming increasingly aware of the necessity to produce material to raise awareness and educate the general public, policy makers and other scientists of the importance and global significance of soil. This is particularly true of soils in northern latitudes where the impacts of global climate change would be dramatic on both a local and global perspective.