Effluent containing high levels of arsenic leaked into the Hunter River from the Kooragang Island chemical plant on 19 August 2011 at 3pm. Arsenic had not been used on the site since 1993, however during a cleanup of a hexavalent chromium spill on the site the week prior, old deposits of arsenic leaked into a storage pond and drained into the Hunter River. It was estimated the arsenic concentration was 0.067 milligrams per litre, exceeding licence limits. Barry O'Farrell, the NSW Premier, said "two spills in a fortnight raise reasonable concerns about systemic failures in the way in which this company is operating its facilities." O'Farrell continued, "I've had a gutful of families being distressed, by potential threats to their safety and threats to their local environment."