Last week Senator Tom Carper (D-DE) introduced the Clean Construction Act of 2011 in an effort to help reduce diesel particulate matter emissions. The bill would require the phased in use of cleaner construction equipment on federally funded transportation projects. The cost for equipment retrofits would come from existing federal transportation funds, limited up to one percent of a project’s cost. The requirement would be applied only to projects located in particulate matter nonattainment areas. A section-by-section summary is available here and a copy of the full legislation is available here.