EPA Explains
The EPA Explains series explores topics that the public wants to learn more about! Whether it's a scientific, regulatory, or agency-specific topic, we've got answers.
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Emergency
This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2025. This website is no longer updated and links to external websites and some internal pages may not work. More information »