the seia can only require mitigation repair or compensation for environmental damage the environmental evaluation service does not have the mandate to consider the larger urban system in assessing a project s environmental impact sea the result is casebycase treatment of environmental externalities that does not consider how each effort at mitigation repair or compensation may undermine or contribute to an urban area s overall environmental quality one mechanism that has been developed is the urban transport system impact study estudio de impacto al sistema de transporte urbanoeistu which sets conditions to mitigate a development s potential impact on roadways and parking for large projects sst nd