We use novel information about fixture-specific water lead levels (WLLs) in Portland, Oregon schools to explore inequalities in students' potential for exposure to lead in drinking water at school. We find that Black and Hispanic students were in classrooms with higher WLLs than white students primarily because they attended different schools. The elevated exposure of students with non-English first languages was also largely driven by sorting into different schools, although there were marginally significant differences between students within the same school. Our findings underscore the importance of broadly targeted remediation efforts like those implemented in Portland to address environmental injustices.