Sop you missed the government funding of cleanup sites. https://nepis.epa.gov/Exe/ZyNET.exe...ge&MaximumPages=1&ZyEntry=1&SeekPage=x&ZyPURL As it says, it provides tax money to clean up sites, but also tries to get the comp[any that polluted to pay too.
Again, the vast majority of sites that get cleaned up are with private money.
The biggest problem with the EPA is delays and the outright arbitrary nature of permitting.