Mercury Levels in Fish, 2011 Monitoring
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Eastmain-1-A and Sarcelle Powerhouses and Rupert Diversion Environmental Follow-Up During Operation Phase – Mercury Levels in Fish, 2011 Monitoring Executive Summary – July 2012 Presented to Hydro-Québec Executive Summary Eastmain-1-A and Sarcelle Powerhouses and Rupert Diversion Mercury Level in Fish 2011 Monitoring Context concentrations were determined by an independent laboratory. Statistical analyses were used to Monitoring at the La Grande complex has shown calculate average mercury levels for fish of that fish mercury levels increase greatly, although consumption size. These average mercury levels temporarily, after the impoundment of reservoirs. are used to submit fish consumption Increases in fish mercury levels may potentially recommendations for each fish species and pose a health risk to regular fish consumers. sampled water body, for approval by the Consequently, for each new reservoir, fish CBHSSJB. consumption advisories are issued to ensure that mercury exposure of fish consumers remains within safe levels. By following the Results recommendations provided in these advisories, Figures 3 and 4 shows the water bodies sampled in consumers may continue to benefit from the health 2011 and the average mercury levels measured in advantages of fish consumption and avoid any ill consumption-size fish, whereas Table 1 shows the effects related to mercury. fish consumption recommendations that will be submitted to the CBHSSJB. Objective Eastmain 1 reservoir The main objective of monitoring mercury levels in fish found in water bodies modified by the For Eastmain 1 reservoir, mercury levels impoundment of Eastmain 1 reservoir and the measured in piscivorous fish (fish that eat other Rupert diversion is to provide the necessary data fish) of consumption size were still increasing to allow the Cree Board of Health and Social in 2011, six years after impoundment. The average Services of James Bay (CBHSSJB) to revise fish mercury levels measured in 20-in. walleye consumption guides. (2.30 ppm), in 28-in. pike (1.64 ppm) and in 33-in. pike (2.16 ppm) were all higher than those Methods obtained in 2009 and higher than the range of values typical of the area’s natural lakes. In 20-in. The main fish species harvested by the Crees were lake whitefish, which feed mainly on insects and captured with gillnets at 18 sampling stations plankton, the average mercury level obtained in covering Eastmain 1 reservoir, the Rivière 2011 (0.28 ppm) is still similar to those of natural Eastmain directly below Eastmain-1 powerhouse, lakes or to those measured since 2007. Opinaca reservoir, the area directly below the La Sarcelle water control structure, Lac Village Opinaca reservoir Sud (a lake in contact with the Eastmain 1 reservoir), Rupert forebay, Rupert tailbay, the As mercury is exported downstream from sections of the Nemiscau and Rupert rivers reservoirs, it was predicted that the impoundment downstream of the diversion bays, a lake in of Eastmain 1 reservoir would also cause an contact with with Rupert forebay, and two natural increase in fish mercury levels in Opinaca control lakes (see Map 1 and Figures 1 and 2). A reservoir, although to a lesser degree. It seems that flesh sample was collected from each fish for the impoundment of Eastmain 1 reservoir did not mercury analysis, and length, weight, sex and cause an increase of mercury levels in 20-in lake sexual maturity were recorded. Mercury whitefish in Opinaca reservoir, as its 2011 mean concentration (0.31 ppm) is not significantly 3 Executive Summary Eastmain-1-A and Sarcelle Powerhouses and Rupert Diversion Mercury Level in Fish 2011 Monitoring different from those measured since 2000, i.e. values measured in natural surrounding lakes, with before the impoundment of Eastmain 1. However, the exception of 28-in. and 33-in pike, for which average mercury levels measured in 2011 in 28-in. levels (1.28 and 2.14 ppm respectively) were pike (1.70 ppm), in 33-in. pike (2.22 ppm) and in significantly higher. However, mercury levels in 20-in. walleye (1.75 ppm) are all significantly smaller-size fish of all monitored species had higher than those measured before the increased in both diversion bays, compared to impoundment of Eastmain 1 reservoir and corresponding values reported in natural lakes, correspond well to values predicted for the sixth which indicates that levels in consumption-size year after impoundment. fish will soon be increasing, as predicted in the project’s Environmental Impact Assessment Lac Village Sud (EIA). A small stream would allow the passage of fish between Lac Village Sud and Eastmain 1 Nemiscau and Rupert rivers downstream of the reservoir. Mercury levels in fish living in this lake diversion bays were thus measured again to determine whether At the three sampling stations along the section of mercury-rich fish from Eastmain 1 reservoir the Rivière Rupert downstream of Rupert forebay, would move into Lac Village Sud. The follow-up mean mercury levels in lake whitefish, lake results indicate no such movement, as mercury sturgeon, pike and walleye of consumption-size levels in all fish of consumption size have, remained in 2011 within the range of values since 2007, remained within the range of values recorded for natural lakes of the area. In the recorded for the area’s natural lakes. Rivière Nemiscau downstream of Rupert tailbay, mercury levels in consumption-size pike (0.87 and Immediately downstream of Eastmain 1 and 1.19 ppm for 28 and 33-in. fish respectively) were Opinaca reservoirs higher than the range of values recorded for the area’s natural lakes. Such an increase, only two In 2011, as was the case in 2009, mercury levels years after the Rupert diversion became in most fish species caught downstream of operational, suggests that mercury levels in all Eastmain 1 reservoir showed significantly higher species will increase in the years to come, as mercury levels than those caught in the reservoir predicted in the project’s EIA. itself or in natural lakes. Downstream of Opinaca reservoir, mercury levels were higher than in natural lakes for piscivorous species, but remained Lake in contact with Rupert forebay similar to those measured in the reservoir itself. As requested by the tallyman of M26 trapline, fish Mercury levels in lake whitefish were higher mercury levels were also measured in a small lake downstream of both reservoirs. communicating with Rupert forebay. In lake trout of this lake, mercury levels remained within the Rupert diversion bays range of values recorded in natural lakes of the area. In 2011, two years after the Rupert diversion became operational, mean mercury levels in consumption-size fish of most species caught in both diversion bays remained within the range of 4 79°0' 78°0' 77°0' 76°0' 75°0' 74°0' SK600 EM400 Sarcelle powerhouse (under construction) Opinaca EA302 Reservoir Lac Rond-de-Poêle (Pikutamaw) EM409 Lac EM402 Émérillon (Achiyaskunapiskuch) James Bay Eastmain ! Eastmain Eastmain-1-A powerhouse Rivière (under construction) Lac EM127 Village Sud EM203 Eastmain-1 powerhouse EM212 EM318 Ch astma em in d'E in 52°0' Eastmain 1 Reservoir EM319 52°0' Nemiscau-1 EM354 Rupert dam Tailbay s e Nemiscau-2 m dam a J - e Arques Lake i a spilling gate B a l Tommy-Neeposh e transfer tunnel d RP020 e t u o Nemaska ! R Lemare dam Rupert Rupert RU002 Forebay Route du Nord Bay Rivière Lac des RP081 Nemiscau Lemare Pontax Montagnes Waskaganish ! Rivière RP076 Rivière Rivière RP048 RP060 Rupert dam Rupert Lac Mesgouez Lac Chemin d Nemiscau e Wa RU813 skag anis h Eastmain-1-A and Sarcelle Powerhouses and Rupert Diversion R EM402 ou Environmental Follow-Up te Sampling Station d u Mercury in Fish Monitoring (2011) N o r Infrastructures d Sampling Stations Rivière Hydroelectric Powerhouse Sources : Lac BDGA, 1 : 1,000,000, MRN Québec, 2002 Dam or control structure Camousitchouane Project data, Hydro-Québec, 2010 Mapping : GENIVAR 51°0' Main road File : 3105_sucA_geq_013_120507an.mxd Access road 51°0' Hydrography 0 9 18 km Waterbodies in natural condition MTM, zone 9, NAD83 Map 1 Lac Lac Théodat Flooded area Evans July 2012 79°0' 78°0' 77°0' 76°0' 75°0' 74°0' Information document for consultation by parties concerned. For any other use, contact: Géomatique, Hydro-Québec Équipement et services partagés Figure 1 Methodology applied for the 2011 follow-up of mercury levels in fish Eastmain 1 Reservoir sector LAKE IN CONTACT NATURAL LAKES WITH EASTMAIN 1 MODIFIED WATERBODIES RESERVOIR ROND-DE-POÊLE ÉMÉRILLON EASTMAIN 1 OPINACA (PIKUTAMAW) (ACHIYASKUNAPISKUCH) VILLAGE SUD RESERVOIR RESERVOIR (CONTROL) (CONTROL) 1 sampling station 1 sampling station 1 sampling station 3 sampling stations 2 sampling stations 13 sampling campaigns 4 sampling campaigns 5 sampling campaigns 3 sampling campaigns 13 sampling campaigns from 1984 to 2011 (1990, 2007, 2009 and 2011) from 1980 to 2011 (2007, 2009 and 2011) from 1981 to 2011 Rupert Diversion sector LAKE IN CONTACT NATURAL LAKE WITH RUPERT MODIFIED WATERBODIES FOREBAY ÉMÉRILLON LAKE NEAR RUPERT NEMISCAU RUPERT RUPERT (ACHIYASKUNAPISKUCH) MISTICAWISSICH RIVER RIVER FOREBAY TAILBAY (CONTROL) RIVER DOWNSTREAM DOWNSTREAM 1 sampling station 1 sampling station 1 sampling station 1 sampling station 3 sampling stations 1 sampling station 4 sampling campaigns 1 sampling campaign 2 sampling campaigns 1 sampling campaign 2 sampling campaigns 1 sampling campaign (1990, 2007, 2009 and 2011) (2011) (1990* and 2011) (2011) (1990* ans 2011) (2011) * Stations in lakes Nemiscau and Des Champs in 1990 3105_suf1_geq_026_120503.ai