U.S. EPA @EPA
#OTD the first round of NPDES permits were issued from 1973-1976, requiring non-municipal facilities to meet 2 technology-based standards: Best Practicable Control Technology Currently Available (BPT) and Best Available Technology Economically Achievable (BAT). #EPAat50 https://t.co/uBf2IuVgSn — PolitiTweet.org