Editing Inco Superstack (section)

==Emissions==
[[Image:Sudbury sunset.JPG|thumb|250px|The Inco Superstack dominates the Sudbury skyline.]]
While the Superstack lowered the ground-level pollution in the city, it has dispersed [[sulphur dioxide]], and [[nitrogen dioxide]] gases over a much larger area. Though not the single source of [[Freshwater acidification|lake acidification]], it appears the heavily industrialized [[Ohio Valley]] has contributed to the ecological problem of lakes as far north as northern Ontario. Research from data gleaned up to the late 1980s demonstrated acid rain to have affected the biology of some 7,000 lakes.

Prior to Vale's purchase of Inco, a major construction effort by Inco in the early 1990s dramatically scrubbed waste gases before pumping them up the Superstack. The upgrades were completed in 1994 and emissions have since been much reduced.<ref>{{Cite web |url=http://www.inco-sudbury-airquality.com/SO2Emissions.htm |title=Process Overview<!-- Bot generated title --> |access-date=March 14, 2007 |archive-url=https://web.archive.org/web/20070701043702/http://www.inco-sudbury-airquality.com/SO2Emissions.htm |archive-date=July 1, 2007 |url-status=usurped }}</ref> By comparison to the plume prior to installation, the plume now disperses quite rapidly and is often see-through even at the stack site.

Emissions reductions and increases in [[thermal efficiency]] have reached the point that [[Stack effect|natural draught]] is no longer sufficient to draw flue gas up the stack and necessitate the use of induced draught fans and/or reheating of the flue gas using natural gas burners.<ref>[http://www.northernontariobusiness.com/Industry-News/mining/CVRD-Inco-plugs-sulphur-dioxide-holes.aspx Northern Ontario Business]</ref>

As well as SO<sub>2</sub> emissions, Inco's Superstack has had very high [[arsenic]], [[nickel]], and [[lead]] emissions to the atmosphere. In 1998, Inco emitted 146.7 tonnes of lead from Copper Cliff while producing 238,500 tonnes of nickel-copper matte. That is 150 times more lead emission than would be permitted by a US EPA-regulated lead smelter producing 238,500 tonnes of lead.<ref>{{Cite web |url=http://www.pollutionprobe.org/old_files/publications/Smelter%20Report.pdf |title=Pollution Probe - Sulphur Dioxide and Toxic Metal Emissions from Smelters in Ontario |page=14 |access-date=August 23, 2012 |archive-url=https://web.archive.org/web/20140109050614/http://www.pollutionprobe.org/old_files/publications/Smelter%20Report.pdf |archive-date=January 9, 2014 |url-status=dead }}</ref> As a result of the excessive lead emissions from the Inco Superstack, soil tests of the surrounding community of Copper Cliff was found to have levels of lead that are sufficient to cause harm to young children.<ref>[http://www.sudburysoilsstudy.com/EN/media/support/reports/SSS_RM_REPORT.pdf Risk Management - Follow Up to the Sudbury Soils Study Human Health Risk Assessment]</ref>