The head of the Environmental Protection Agency will meet with state, local and tribal officials and community members when she visits Colorado on Wednesday to see the impact of a 3 million-gallon mine waste spill. The EPA has said the flows are moving too fast for the contaminants to pose an immediate health threat and that the heavy metals will likely be diluted over time so they don't pose a longer-term threat. The EPA has said the current flows are too fast for the contaminants to pose an immediate health threat, and that the heavy metals will likely be diluted over time so they don't pose a longer-term threat, either.