Risk Assessment of Expected Run-off from a Highway

Abstract

Because the Second Tomei Expressway is arranged along mountainsides, the influence that the road run-off gives to the water quality of the downstream river has been worried. For a region where this highway run-off flowed into a river that is a source for drinking water, risk of health impact of the road run-off was assessed. Health risk of heavy metals, PAHs, and THMs were considered. As a result, it was found that probability of cancer caused by bromodichloromethane could be higher than 10^-5. In addition, it was suggested that monitoring and management of the water quality in the basin will be required because comparatively high risks ware shown about some heavy metals and THMs.