Ecology issued its final modified industrial stormwater general permit last week, which will become effective on July 1, 2012.  Among the changes in the modified permit is a requirement that permittees submit and obtain Ecology approval on engineering report and plans for any Level 3 corrective action that requires the site-specific design or sizing of stormwater structures, equipment, or processes.  This has the potential to significantly drive-up costs for those permittees that are obligated to install treatment best management practices.  A copy of the final modified permit and a summary of the changes can be found here: permit, summary of changes.