The federal government is providing four grantstotaling $6.5 million to help New Jersey clean up contaminated sites and encourage economic development. The money, much of which comes from President Joe Biden’s $1 trillion bipartisan infrastructure law, would go towards cleaning up what are known as brownfields, which could be redeveloped but for the presence or potential presence of contaminants, pollution or hazardous materials. “The brownfields program is a powerful tool that helps overburdened communities in New Jersey address local inequities by providing a means to revitalize properties a…