Influence of the traffic volume on contaminant load of infiltration plants
For the evaluation of the material load of traffic surface discharges in the technical sets of rules the average daily traffic volume is consulted. Recommendations for infiltration plants for traffic surface discharges are given according to the average daily traffic volume. This approach is questioned by the composition of literature data for expiration values of different traffic surface discharges. However, these literature data are not necessarily reliable. Because many boundary conditions, as for example sampling time and sampling mixes, are missing.
If it would be shown however the fact that the traffic volume does not have direct influence on the material load of traffic surface discharges, it would lead then to a wrong estimation of the load and service life of infiltration plants. This would have extensive consequences for a possible entry of pollutants in ground and groundwater.
For this reason a comprehensive sampling is accomplished by existing infiltration plants with an encouraged surface zone. Plants with different age, comparable use and volume of traffic are confronted. For this representatively the heavy metals copper, zinc, lead and cadmium are analyzed. For the evaluation of the comparability all boundary conditions are included and evaluated, as well.