Throughout August and December 2011 Orica had six major chemicals incidents or leaks in Australia. The first one was a leak of hexavalent chromium from its ammonium nitrate plant near Stockton that affected 70 households; the second one was the release of arsenic into the Hunter River at Newcastle; the third was of mercury vapours from its Botany site; the fourth was a leak of ammonia from its site at Kooragang; the fifth was an ammonium nitrate leak of at its Kooragang Island plant, only a day after being allowed to reopen; and the sixth incident was a sulphuric acid leak of approximately at its Port Kembla site. The fourth leak triggered a public forum and NSW Government investigation into the leaks, and the temporary shut down of the Kooragang Island plant.