Number of hazardous waste sites in the U.S. 2025, by state

New Jersey is home to the largest number of hazardous waste sites – or Superfund sites – across the United States, with 114 locations as of March 2025. California and Pennsylvania followed, each with over 90 sites at the time.

What is a Superfund site?

In 1980, the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) was passed, which allowed the Environmental Protection Agency to clean up the most contaminated sites in the United States. The locations managed under this program are commonly known as Superfund sites and include hazardous waste sites such as landfills and mines, where toxic waste has been dumped. As of March 2025, 1,318 Superfund sites across the 50 U.S. states were listed on the National Priorities List (NPL). 

Hazardous waste shipments within the U.S.

Featuring the sixth-highest number of hazardous waste sites across the United States, Texas received the largest volume of hazardous waste from other states in recent years, at nearly 650,000 metric tons. The southern state was also the largest shipper of hazardous waste within the North American country, with outbound shipments surpassing inbound by some two million metric tons.