Countermeasures for environmental problems of expressways and environmental impact assessment in Japan.

Since the early 1970s conflicts have occurred frequently between resident groups, which wanted a quiet and clean environment along proposed national expressways, and the Japan Highways Public Corporation (JHPC).This paper, at first, describes these conflicts as well as complaints and claims arising from residents along the expressways.The various countermeasures which the JHPC implemented to abate noise and air pollution and to conserve the surrounding environment are then reviewed and presented.