Monitoring results May 1999 - June 2004
The Danish Pesticide Leaching Assessment Programme
(Varslingssystem for udvaskning af pesticider til grundvand - VAP)
|Download the report
Price: kr 200.00
Geological Survey of Denmark and Greenland
Øster Voldgade 10, DK-1350 Copenhagen, Denmark
Phone: +45 38 14 20 00, fax +45 38 20 50
Table of contents
1.1 OBJECTIVE .
1.2 STRUCTURE OF THE PLAP .
2 PESTICIDE LEACHING AT TYLSTRUP
2.1 MATERIALS AND METHODS .
- 2.1.1 Site description and monitoring design .
- 2.1.2 Agricultural management.
- 2.1.3 Model set-up and calibration .
2.2 RESULTS AND DISCUSSION .
- 2.2.1 Soil water dynamics and water balances
- 2.2.2 Bromide leaching.
- 2.2.3 Pesticide leaching.
3 PESTICIDE LEACHING AT JYNDEVAD .
3.1 MATERIALS AND METHODS .
- 3.1.1 Site description and monitoring design
- 3.1.2 Agricultural management.
- 3.1.3 Model set-up and calibration .
3.2 RESULTS AND DISCUSSION
- 3.2.1 Soil water dynamics and water balances.
- 3.2.2 Bromide leaching.
- 3.2.3 Pesticide leaching.
4 PESTICIDE LEACHING AT SILSTRUP
4.1 MATERIALS AND METHODS .
- 4.1.1 Site description and monitoring design
- 4.1.2 Agricultural management.
- 4.1.3 Model set-up and calibration .
4.2 RESULTS AND DISCUSSION
- 4.2.1 Soil water dynamics and water balances.
- 4.2.2 Bromide leaching.
- 4.2.3 Pesticide leaching.
5 PESTICIDE LEACHING AT ESTRUP .
5.1 MATERIAL AND METHODS.
- 5.1.1 Site description and monitoring design
- 5.1.2 Agricultural management.
- 5.1.3 Model set-up and calibration .
5.2 RESULTS AND DISCUSSION
- 5.2.1 Soil water dynamics and water balances.
- 5.2.2 Bromide leaching.
- 5.2.3 Pesticide leaching.
6 PESTICIDE LEACHING AT FAARDRUP.
6.1 MATERIALS AND METHODS .
- 6.1.1 Site description and monitoring design
- 6.1.2 Agricultural management.
- 6.1.3 Model set-up and calibration .
6.2 RESULT AND DISCUSSION .
- 6.2.1 Soil water dynamics and water balances.
- 6.2.2 Bromide leaching.
- 6.2.3 Pesticide leaching.
7 PESTICIDE ANALYSIS QUALITY ASSURANCE.
7.1 MATERIALS AND METHODS .
- 7.1.1 Internal QA
- 7.1.2 External QA
7.2 RESULTS AND DISCUSSION
- 7.2.1 Internal QA
- 7.2.2 External QA
7.3 SUMMARY AND CONCLUDING REMARKS
8 SUMMARY OF MONITORING RESULTS .
In 1998, the Danish Parliament initiated the Pesticide Leaching Assessment Programme (PLAP), an intensive monitoring programme aimed at evaluating the leaching risk of pesticides under field conditions. The objective of the PLAP is to improve the scientific foundation for decision making in the Danish registration procedures for pesticides. The specific aim is to analyse whether pesticides applied in accordance with current regulations leach to the groundwater in unacceptable concentrations. The programme presently evaluates the leaching risk of 29 pesticides applied at five agricultural sites ranging in size from 1.1 to 2.4ha. The results so far show that:
The PLAP initially evaluated the leaching risk at six agricultural sites representing a range of Danish soil and climate conditions. Monitoring at the Slaeggerup site was terminated on 1 July 2003, and results from that site are not included in the present report. For the monitoring results from this site see Kjær et al. (2004). The pesticides were all applied at the maximum permitted rate. In order to describe water transport a bromide tracer was also applied to the fields. Bromide and pesticide concentrations are measured monthly in both the unsaturated and the saturated zones, and weekly in the drainage water. This report presents the monitoring results from the five agricultural sites at which monitoring is still performed and covers the period May 1999–June 2004. The main focus is on evaluating the leaching risk of those pesticides applied during 2002. The report should be viewed as an interim report because not all of the pesticides applied have been monitored for at least two consecutive years.
- Of the 29 pesticides applied, seven did not leach during the current monitoring period.
- The monitoring data indicate pronounced leaching of eight of the applied pesticides or their degradation products. Thus ethofumesate, bentazone, glyphosate and its degradation product AMPA, metamitron and its degradation product desamino-metamitron, as well as the degradation products of metribuzin, terbutylazine, pirimicarb, and rimsulfuron leached from the root zone (1 m b.g.s.) in average concentrations exceeding the maximum allowable concentration of 0.1 µg/l. Except for a degradation product of metribuzin, pronounced leaching was mainly confined to a depth of 1 m, where pesticides were frequently detected in samples from suction cups and drainage systems. Only the metribuzin degradation product was detected beneath this depth at an average concentration exceeding 0.1 µg/l.
- The monitoring data also indicate leaching of a further 14 pesticides, but not in high concentrations. Thus although the concentration exceeded 0.1 µg/l in several samples, the average leaching concentration did not.