Monitoring the remediation of Halifax Harbour after 250 years of contamination

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This proposal will address the issue of monitoring the progress of mitigation after a new sewage treatment system is introduced to Halifax Harbour for the first time after 250 years of raw effluent being placed in the harbour. Although there will be monitoring of the water quality after treatment is introduced, the real problems are encountered in the sediments where there is currently no plan sample or monitor changes. Given the fact that there is a fishing industry in the harbour now that harvests benthic animals such as lobsters, it is important to know what is accumulating in the harbour and if it will decrease as mitigation progresses. Our plan will be to utilize ship time provided by the Halifax Regional Municipality (HRM) to collect benthic samples coincident with water samples and monitor the benthic foraminifera and other biota together with heavy metals and PAH's in these samples as mitigation progresses after summer of 2006-2007 when the first treatment plant comesonline; we already have sets of samples from 2004 and 2005. We will also reconstruct the history of pollution from pre-historic times to determine what the pre-impact baseline was using foraminifera and tintinnids as proxies. In virtually no cases are data available prior to introduction of stresses; using proxies of the benthic environment (e.g. benthic foraminifera) we can reconstruct the conditions prior to impacts. The previous studies of foraminifera in core material had no coincident geochemical data or adequate dating as will be the case in this study. We will be able to determine after 2 years if the system is responding to remediation and to what degree. In parallel "sentinel" species will also be used to monitor the return of key biota to the system.  The HRM situation is unique in Canada where we have begun sampling before the treatment started and can follow it for several years following the remedial treatments. This type of pre-historical reconstructionn could influence public policy in form of new standards where the benthic environment must be considered as well as water quality. This project includes, as supporting organisations, government, civic and international support (Egyptian Cultural Affairs).