The Associated Press is reporting clean-up crews have begun the sixth and final season of PCB dredging in the upper Hudson River. Regional Environmental Protection Agency Administrator Judith Enck said this is an important year in the history of the river. Work on the estimated $2 billion cleanup began Thu., May 7. The season typically runs into the fall. GE began discharging PCBs into the river 70 years ago and continued to do so for decades when the compounds were used as coolants in electrical equipment. The practice turned the Hudson River into a polluted Superfund site for 200 miles from its northern reaches to New York Harbor. Flood plain work, habitat reconstruction along the river and long-term monitoring will continue after dredging is finished. Read the full story in the Daily Freeman.