"The U.S. Environmental Protection Agency is moving forward with more cleanup of lead in East Helena residential yards following the closing of a public comment period.
The federal agency said Friday in a news release it finalized what is called an "explanation of significant differences" document that lowers the soil-lead cleanup level at the East Helena Superfund Site from 500 parts per million to 400 ppm. The new language also removes the 1,000 ppm cleanup action level previously used to trigger yard cleanups at the site......
The EPA also recently released national guidance lowering the screening level for soil-lead in residential yards to 200 ppm, or to 100 ppm if there are multiple sources of lead contamination."