Organic Micropollutants in Roof Runoff - A Study of the Emission/Retention Potential of Green Roofs
Résumé
The incidence of extensive roof greening structures in the contamination of roof runoff has been analysed for three families of organic micropollutants (polycyclic aromatic hydrocarbons [PAHs], alkylphenols [APs], and bisphenol A [BPA]) by means of both laboratory leaching tests and field experiments. For PAHs, which do not have any local source on the green roof and originate only from atmospheric fallout, the green roof behaves as a sink and reduces by a factor 10 the emitted loads compared to a conventional flat roof. APs and BPA however can be emitted by the synthetic materials that constitute the roofing structure (e.g., roof sealing, drainage material, filter, evacuation pipes). Potential emissions of BPA and nonylphenol (NP) from the geotextile, the sealing membrane and PVC pipes have especially been identified. Field results confirm increased NP and octylphenol (OP) emissions in the green roof runoff. However, the concentrations and loads remain within the range of values observed for other types of urban surfaces.
Origine | Fichiers produits par l'(les) auteur(s) |
---|
Loading...