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January 2009
Environmental Impact Statement for the Lower Churchill Hydroelectric Generation Project
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Water Quality and Chlorophyll Study
JWEL PROJECT 1218
WATER QUALITY ANDCHLOROPHYLL STUDY
(LHP 99-08)
FEBRUARY 2001
JWEL PROJECT 1218
WATER QUALITY ANDCHLOROPHYLL STUDY
(LHP 99-08)
PREPARED FOR
NEWFOUNDLAND AND LABRADOR HYDROLAJ3RADOR HYDRO PROJECT
500 COLUMBUS DRIVEP. 0. BOX 12400
ST. JOHN'S, NEWFOUNDLANDAlA 2X8
PREPARED BY
JACQUES WHITFORD ENVIRONMENT LIMITED607 TORBAY ROAD
ST. JOHN'S, NEWFOUNDLANDAlA 4Y6
February 12, 2000
EXECUTIVE SUMMARY
In 1999, Jacques Whitford Environment conducted a water and chlorophyll study to characterizebaseline conditions in lakes and reservoirs of the Churchill River system. The focus was on surface anddeep-water quality as well as chlorophyll, phytoplankton and zooplankton to describe and quantifyproduction levels in these lakes. Determination of mercury levels in water and zooplankton were alsoincluded in the scope of work. Sampling campaigns were completed in seven lakes in each ofSeptember and October 1999.
Water quality results were similar to those of Churchill River in 1998 (JWEL 1999b) and reservoirs ofQuebec. The water is very dilute, neutral to slightly acidic in nature, with very low levels of dissolvedsolids. Nutrient levels were very low.
The plankton and chlorophyll data for 1999 fall within the range of the 1998 observations with theexception of Lobstick Lake where new maxima for chlorophyll concentration and for zooplanktonbiomass were established.
A comparative review of data on water transparency, chlorophyll, primary production, phytoplanktoncomposition and biomass, and zooplankton composition and biomass was undertaken for four reservoirsystems: the Churchill watershed in Labrador, the La Grande complex in northern Quebec, the Southern
Indian Lake system in northern Manitoba and Cat Arm Reservoir on the Great Northern Peninsula ofinsular Newfoundland.
Churchill watershed lakes exhibited deeper Secchi disk depths and higher light transmission rates thanany of the other reservoirs. Chlorophyll concentrations were greater than those at La Grande were but
well below those for Southern Indian Lake; chlorophyll data are not available for Cat Arm Reservoir.
Phytoplankton composition in the Churchill lakes was dominated by nanoplankton forms similar to thecommunities at La Grande and Cat Arm but different from those at Southern Indian Lake where largecolonial diatoms and blue-green filamentous algae frequently dominated. Summer phytoplanktonbiomass concentrations in the Churchill lakes were comparable to those at Cat Arm and La Grande, allof which were lower than those observed in Southern Indian Lake.
Primary production in the Churchill lakes was greater than that in Cat Arm Reservoir where low lightpenetration severely restricted the photosynthetic zone, and was comparable to pre-impoundmentproduction at La Grande. The primary production rates of all of these systems was much lower thanpre- and post-impoundment levels in Southern Indian Lake. Specific production rates in the Churchilllakes were lower than at La Grande and Southern Indian Lake, which may be indicative of a greaterdegree of nutrient stress.
JWEL Project 1218 LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page i
Zooplankton communities in the Churchill lakes were dominated by cladocera with calanoid copepodssub-dominant, similar to the communities observed in Cat Arm Reservoir and in the La Grande complexbut quite different from Southern Indian Lake where cyclopoid copepods predominated with calanoidssub-dominant. Biomass levels in the lentic lakes of the Churchill watershed were comparable to pre-impoundment levels at La Grande but lower than post-impoundment levels at Cat Arm Reservoir.Biomass data are not available for Southern Indian Lake.
Mercury concentrations in water were determined to be comparable to those determined for Quebec
reservoirs for total mercury, and somewhat lower for methylmercury as all samples from the ChurchillRiver lakes returned results below detection. Similarly, the mercury levels determined for zooplanktonwere within the range of those found in Quebec reservoirs and natural lakes.
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study • Februaiy 12, 2000 Page ii
TABLE OF CONTENTS
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Page No.
INTRODUCTION 11.1 Churchill River Power Project 11.2 Environmental Baseline Characterization Program 11.3 Water Quality and Chlorophyll Study 11.4 Study Team 2
2 PURPOSE AND SUMMARY OF STUDY OBJECTIVES 5
3 DESCRIPTION OF STUDY AREA 6
4 METHODS 84.1 Literature Review 84.2 Field Sampling 8
4.2.1 Station Locations 84.3 Field Methods 9
4.3.1 Water Quality 94.3.2 Chlorophyll 114.3.3 Zooplankton Biomass 114.3.4 Zooplankton Mercury Body Burden 11
5 RESULTS AND DISCUSSION 125.1 Field Measurements 12
5.1.1 Water Transparency 145.1.2 Water Temperature 145.1.3 Field Lab Results 18
5.2 Water Quality 185.3 Chlorophyll 205.4 Phytoplankton Composition and Biomass 205.5 Primary Production 215.6 Zooplankton Biomass 225.7 Mercury Concentrations in Water and Zooplankton 25
6 CONCLUSIONS 28
7 REFERENCES 30
LIST OF APPENDICES
Appendix 1 1999 Water Quality and Chlorophyll Study - Field DataAppendix 2 1999 Water Quality and Chlorophyll Study - Field Lab ResultsAppendix 3 1999 Water Quality and Chlorophyll Study - Analytical Lab Results - WaterAppendix 4 1999 Water Quality and Chlorophyll Study - Chlorophyll Analysis ResultsAppendix 5 1999 Water Quality and Chlorophyll Study - Zooplankton Analysis ResultsAppendix 6 1999 Water Quality and Chlorophyll Study - Mercury in Water and Zooplankton
IWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page iii
LIST OF TABLES
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Page No.
Table 1.1 Water Quality and Chlorophyll Study Team 2Table 4.1 Station Locations and Water Depth - 1999 Water Quality and Chlorophyll Study 9Table 4.2 Analytical Requirements for Water Quality 10Table 5.1 Summary of Field Measurements During the Water Quality & Chlorophyll Study 12Table 5.2 Summary of Water Chemistry for Sampling in September-October 1999 19
LIST OF FIGURES
Page No.
Figure 3.1 Churchill River Power Project 1999 - Water Quality and Chlorophyll - Study Area 7Figure 5.1 Secchi Depths - July-September 1998 and September-October 1999 13Figure 5.2 Water Temperature Ranges for 1998 and 1999 Sampling Campaigns 15Figure 5.3 Lake Temperature Profiles - September 1999 16Figure 5.4 Lake Temperature Profiles - October 1999 17Figure 5.5 Chlorophyll Concentrations - July-September 1998 and September-October 1999 23Figure 5.6 Zooplankton Biomass - July-September 1998 and September-October 1999 24Figure 5.7 Total Mercury Concentration in Water 26Figure 5.8 Mercury Concentration in Zooplankton 27
JWEL Project 1218 . LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page iv
1 INTRODUCTION
Jacques Whitford Environment Limited (JWEL) were contracted by Newfoundland and Labrador Hydro
(Hydro) through the Labrador Hydro Project office (LRP) to provide consultant services to conduct the1999 Water Quality and Chlorophyll Study of the Churchill River Power study area. The JWEL study
team included Drs. Roy Krioechel and Malcolm Stephenson who were on the 1998 projects, in additionto personnel from Génivar who have been involved in the Hydro Québec monitoring programs for the
past two decades. This provided a team with the combined experience of previous Labrador Hydro andHydro-Quebec studies.
1.1 Churchill River Power Project
On March 9, 1998 Hydro was directed to begin formal negotiations with Hydro-Quebec to work out
detailed agreements for the development of up to 4,000 megawatts of additional power from theChurchill River system. The proposed Project involves:
• expansion of the existing Churchill Falls project through the partial diversion of Romaine Riverin Quebec;
• development of a 2,200-megawatt generating facility at Gull Island;• possible development of an 824-megawatt generating facility at Muskrat Falls;• two 735 kV transmission lines, one from Gull Island to Churchill Falls, and a second from Gull
Island to the Montagnais station in Quebec;• a possible 235 kV transmission line from Muskrat Falls to Gull Island; and• a 800-megawatt HVDC transmission line (with a continuous rating of 400 kV) from Gull Island
to Soldiers Pond, near Holyrood, and a submarine cable crossing of the Strait of Belle Isle.
Although the project elements have changed slightly since the start of the 1998 field season, the studyareas remain fundamentally unchanged.
1.2 Environmental Baseline Characterization Program
LHP conducted field programs in 1998 and 1999 to characterize the environmental baseline conditionsfor the area of the proposed project. The water quality and chlorophyll study was one of the freshwaterprograms conducted in the summer/fall of 1999.
1.3 Water Quality and Chlorophyll Study
The Project is anticipated to affect water quality, water quantity, nutrient transport and the downstreamtransport of zooplankton movement in the Churchill River and Smallwood Reservoir system. LHPidentified the requirement for additional baseline information for the lakes of these reservoir systems.
IWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . Februaiy 12, 2000 Page 1
To that end a program was undertaken in 1999 to provide comparative data with the 1998 program aswell as extend the scope and spatial extent of the 1998 study.
1.4 Study Team
The water quality and chlorophyll study was conducted by Jacques Whitford Environment Limited(JWEL) in association with Dr. Roy Knoechel, Biology Department, Memorial University ofNewfoundland, and Génivar, Quebec City. Study team members included a project manager, scientificauthority, scientific advisor, other scientists as well as technical field personnel (Table 1.1). All teammembers have in-depth knowledge and experience in their fields of expertise as well as past projectexperience on the Churchill River or the various Hydro-Quebec projects. Both JWEL and Génivar haveISO 9001 certification.
Brief biographical statements, highlighting project roles and responsibilities and relevant education andemployment experience, are provided below.
Table 1.1 Water Quality and Chlorophyll Study Team
Personnel Role AffiliationBruce Bennett Scientist, Project Manager JWEL - St. John'sDr. Roy Knoechel Scientific Authority (Primary Productivity) Memorial UniversityDr. Malcolm Stephenson Scientific Advisor (Water Quality) JWEL - FredenctonJean-Francois Doyon Aquatic Biologist, Literature review, Manager GénivarEric Luiker Biologist, Field Team JWELDaniel Dussault Field Team, data archiving GénivarDarren McKay Field Technician Irmu Environmental
JWEL has conducted environmental consulting in Newfoundland and Labrador since 1980, providingexperienced management, scientific, and support staff with extensive field experience in the province.JWEL assembled an experienced team with emphasis on experience in Labrador, experience at LaGrande and local aboriginal involvement for the chlorophyll and water quality study.
Bruce Bennett, B.Sc.(Hons) Trent University, is a senior aquatic scientist with JWEL, St. JoIm's, NF,with almost 25 years experience in conducting freshwater studies. Mr. Bennett was Project Manager forthe chlorophyll and water quality study as well as for the primary productivity and plankton biomassstudy, and four other freshwater studies conducted for LHP in 1998. Mr. Bennett was the projectmanager for the freshwater ecosystem component of the Voisey's Bay environmental baselinecharacterization program and current studies in western Labrador. Over the past two decades, Mr.Bennett has completed numerous freshwater fisheries studies relating to mining and hydroelectricprojects, on the Island and in Labrador. His work experience includes numerous environmental baseline
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . February 12, 2000 Page 2
studies, environmental impact statements, environmental effects monitoring programs, and public andstakeholder consultation.
Roy Knoechel, Ph.D. McGill University, is an Associate Professor of Biology at Memorial Universityof Newfoundland and also works as an associate consultant. Dr. Knoechel was selected to be ScientificAuthority for this study. He was selected for this role based on his expertise in and extensive researchon aquatic ecosystems, including his role in the 1998 LHP study. Dr. Knoechel was the scientificauthority and reviewer for the freshwater primary productivity studies that were conducted by JWEL aspart of the Voisey' s Bay environmental baseline characterization program. Dr. Knoechel has conducted
numerous ecological investigations in freshwater environments addressing a wide range of organisms,processes and levels of organization. His current research projects include studies on the effectivenessof pond enrichment on enhancing salmonid production and acid rain recovery (through alkalinitygeneration), and trophic evolution of the Cat Arm reservoir during the reservoir's transformation from asmall, rapidly flushing pond to a large reservoir with a longer water residence time. Dr. Knoechel haspublished numerous articles and papers on fish and other species in ponds and rivers in Newfoundland.
Malcolm Stephenson, Ph.D. University of Guelph, is a Senior Aquatic Scientist with JWEL inFredericton. He has a degree in fisheries and wildlife biology, supplemented by broad post-graduatetraining in aquatic science. Dr. Stephenson was the Scientific Authority for the water and sedimentstudy in 1998 and he served as scientific advisor for the water quality component of this study. Hisprimary areas of specialization are environmental impact assessment and risk assessment, emphasizingmulti-disciplinary linkages to environmental restoration, hydrology, ecological modelling,ecotoxicology, geochemistry and applied aquatic ecology.
Jean-Francois Doyon M.Sc. McGill University, is a senior biologist with Génivar since 1989. He hasbeen involved in Hydro-Quebec studies in Northern Quebec since 1990. With Roger Schetagne andRichard Verdon, he has been responsible for the environmental monitoring program of Hydro-Quebec at
the La Grande complex since 1993, which includes water quality, mercury in fish and in other aquaticorganisms (phytoplankton, zooplankton, benthic invertebrates), and fish populations. He is also theproject leader for the environmental monitoring program of the Robertson Reservoir, on the Lower
North Shore of St-Lawrence River since 1997, where surveys of water quality, mercury and fishpopulations are conducted. He is co-author of 4 publications on mercury as well as the co-author of thelast synthesis report of Hydro-Quebec on mercury in reservoirs. Mr. Doyon compiled the literaturereview on water quality and plankton work conducted by Hydro-Quebec in northern Québec.
Eric A. Luiker, M.Sc. University of Guelph, is an aquatic biologist with JWEL in St. John's. Mr.Luiker was the project coordinator for the Voisey's Bay mine/mill freshwater field programs and the10CC Luce Deposit aquatic study. These studies included macroinvertebrate sampling, sediment andwater sampling, fish studies, data analysis and report preparation. In 1998, Mr. Luiker was in the fieldteam for the fish migration study and has gone on to coordinate the data management of that study. Hehas also conducted other freshwater and fish surveys including programs in western Labrador and has
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 3
extensive surveying experience including work with total stations, general land surveying techniques,bathymetry, and GPS data collection.
Daniel Dussault has worked as a technician for Génivar for over 15 years. He was on the original teamthat began in 1976-1977 as the ecological monitoring network of the Société d'énergie de la Baie James
at the La Grande complex that has been carried out by Hydro-Quebec since 1986. He was in charge ofthe field programs for water quality, fish populations and mercury between 1978 and 1990. Mr.Dussault also carried out several other field programs on water quality (e.g., Sainte-Marguerite project(1990-199 1), monitoring program of Robertson reservoir (1990, 1997 and 1999) both on North Shore ofthe St Lawrence River, Tabaret Project (1998) in Abitibi. As a result, he has mastered the samplingprocedures and quality control procedures used in the field by Hydro-Quebec and he contributed to thereport of Somer (1992). He was also involved in studies conducted on the watershed of the CaniapiscauRiver and on the Great and Little Whale River, in northern Quebec. He also managed the three hugedata bases created by Hydro-Quebec (water quality, reservoir, and fish). Mr. Dussault participated infieldwork to provide the Hydro-Quebec sampling and quality control procedures as well as to compilethe data into the Hydro-Québec database.
Darren McKay is resident of Sheshatshiu Labrador and was employed as a technician during the fieldcomponent of the study. Mr. McKay's services were provided through limu Environment.
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 4
2 PURPOSE AND SUMMARY OF STUDY OBJECTIVES
The main objective of the water quality and chlorophyll study was to assess baseline conditions in theChurchill River and Smallwood Reservoir system prior to development of the Churchill River PowerProject. Seven lakes were sampled to represent lakes that are yet unaffected by impoundment, lakes that
are reservoirs, lakes downstream of reservoirs, and a control lake upstream of existing and proposedreservoirs. Chlorophyll concentrations are used as an index of primary productivity of the seven waterbodies sampled. Sampling was conducted during summer (early September) and autunm (earlyOctober) to provide a representative range of values from the productive season of the Churchill Riversystem. This study provides the information required for future environmental assessment of the Projectand baseline conditions for future follow-up monitoring.
The specific objectives of the study were to determine water quality and chlorophyll concentrations atselected locations within the Churchill River and Smaliwood Reservoir system. Methods employedwere consistent with those used in 1998 where applicable. All new work employed methods consistentwith those used by Hydro-Quebec in the La Grande Project and similar studies.
Water quality sampling was not conducted in the 1998 primary productivity study, which was restrictedto characterizing the productive surface waters (0 to 10 m) in each of the lakes. Sampling of surfacewater and bottom water in the lakes will identify deep-water areas where oxygen depletion may occur.
JWEL Project 1218 LJ-JP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 5
3 DESCRIPTION OF STUDY AREA
The study area for the Water Quality and Chlorophyll Study includes seven standing water bodies(lakes) within: the Churchill River, from Muskrat Falls upstream to Churchill Falls; Atikonak Lake; andthe Smaliwood Reservoir system:
Churchill River:
• Lake Winokapau; and• Gull Lake, between Gull Island and Muskrat Falls.
Smaliwood Reservoir system:• Atikonak Lake;• Ossokmanuan Lake';• Lobstick Lake; and• Michikamau Lake.• Lac Joseph (control location)
The locations of these lakes are shown on Figure 3.1.
With the formation of the Smaliwood Reservoir system, Gabbro Lake and Ossoknlanuan Lake became a single water body.To expedite sampling in 1999, the north end of Ossokmanuan Lake was sampled - at a location not far from the Gabbro Lakestation sampled in 1998 (JWEL 1999a). To facilitate comparisons between the two years of study, the station sampled in1999 is referred to as Gabbro Lake.
IWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 6
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4 METHODS
The following methods were developed in consultation with LHP and are based on the objectives andmethods contained in the Terms of Reference and those used by the study team for previous studiesconducted for LHP and for Hydro- Québec.
4.1 Literature Review
Relevant literature on primary productivity, chlorophyll concentration (as an index of primary
productivity), water quality, and plankton biomass in Labrador, Quebec, Manitoba and other areas has
been reviewed and summarized to provide a context for the results of this study. Special emphasis hasbeen placed on information collected at La Grande.
4.2 Field Sampling
Sampling was conducted in two campaigns to characterize the seasonal variation within the seven sites.
The first campaign was conducted from August 30 to September 3 to represent summer low-flowconditions. The second campaign conducted from October 4-8 represents autun-in high-flow conditions.Sampling was conducted from a floatplane, as in 1998, to provide a suitably manoeuvrable yet stablework platform. Using the plane facilitated sampling two or three widely separated lakes in a day - a featthat could not be duplicated by boat alone.
The sampling frequency and spatial extent was carefully considered to provide representative coverage
of the study area. Prior to initiation of sampling, it was agreed that statistical analysis of the data wouldnot be required for a program of this scope. This decision was due to the absence of comparable priordata for these lakes. However, these data may be readily examined in comparison to any future data.
4.2.1 Station Locations
Each lake was sampled at a readily accessible and relatively open location with a depth of at least 10 mas was done in 1998 (JWEL 1999a). A portable Hummingbird Wide 100 depth sounder was used toselect suitably deep water for sampling stations. GPS coordinates were obtained using hand-heldGarmin 12 GPS or aircraft instrumentation to identify the sampling locations (Table 4.1 and Figure 3.1).
Concrete anchors were placed at each station to mark them for October sampling and to provide amooring for the sampling platform. These moorings may survive from year to year to facilitate futuremonitoring.
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . Februaiy 12, 2000 Page 8
Table 4.1 Station Locations and Water Depth - 1999 Water Quality and Chlorophyll Study
Station # Location Latitude Longitude Depth (m)
CHO1 1 Lac Joseph N 52° 48.663' W 65° 09.530' 66
CHO12 AtikonakLake N52°35.160' W64°32.608' 11.5
CHO13 Gabbro Lake N53°38.286' W65°15.705' 14
CHO14 Lobstick Lake N 54° 08.6 10' W 65° 08.742' 17.5
CHO15 Michikamau Lake N 54° 04.581' W 63° 47.598' 27.5
CHO16 WinokapauLake N53°12.386' W63°08.256' 115
CHO17 GuliLake N52°57.920' W61°19.436' 14
4.3 Field Methods
The field methods employed during these campaigns were suitable for low production oligotrophic lakessuch as are common in northern latitudes. These are summarized below.
4.3.1 Water Quality
At each sampling location, field measurements were taken to determine water temperature, transparency(Secchi depth), dissolved oxygen, conductivity and pH. These were obtained with a HYDROLABportable meter system. Field measurements were taken at intervals through the water colunm todetermine the presence of a thermocline. One-metre intervals were used from surface to 10-rn depth.Below 10 rn, the intervals were 1-rn, 5-rn, or 10-rn depending on the total depth at the station.Measurements were also obtained for a 0-10 rn depth integrated sample.
In addition to the field measurements, samples were collected for in-field analysis as a validation ofoxygen and alkalinity measurements. Each evening, the samples for the current day were analyzed fortemperature, pH, conductivity, oxygen concentration (Winkler titration), alkalinity, bicarbonates, andtotal inorganic carbon.
Water sample bottles were obtained from the analytical laboratory (Philip Analytical) and were labelledprior to field sampling. Water sampling deck sheets, compatible with those used by Hydro-Quebec wereused to document all field records. This allows integration of the data collected in 1999 into the waterquality database of Hydro-Québec.
JWEL Project 1218 LHP 1999 Water Quality & Chlorophyll Study Februaty 12, 2000 Page 9
Bottles used for mercury, trace metal and total organic carbon analysis contained preservatives(potassium dichromate, nitric acid, or sulphuric acid) which were added at the laboratory prior toshipment.
Water samples were collected from aliquots drawn using a 1-rn long sampler deployed at each metre
depth from surface to 10 rn. This method provides an integrated sample representing the productivesurface waters of lakes (0-10 m). At any station where the water column displayed stratification, asample was also collected at 1 m above the bottom using an Alpha water sampler (Somer 1992).
As done in 1998 and for the La Grande complex water sampling, blind duplicate water samplescomprising 10% of the total required samples were collected and submitted for laboratory analysis. Allsamples (including field blanks) were stored in coolers at 4°C until shipped to Philip Analytical inMontreal. A list of the specific parameters and the reporting detection limit are provided in Table 4.2.
Table 4.2 Analytical Requirements for Water Quality
Parameter Reporting DetectionLimit (mgIL)
Metals (ICP-MS) Reporting DetectionLimit (mg/L)
Chloride 0.2 Aluminum 0.005Sulfate 0.5 Antimony 0.002Calcium by ICP-OES 0.05 Arsenic 0.002Magnesium by ICP-OES 0.01 Barium 0.005Sodium by ICP-OES 0.02 Beryllium 0.005Potassium by ICP-OES 0.06 Bismuth 0.002Colour (real) 1 UCV Boron 0.005Tannin.s 0.2 Cadmium 0.0002Turbidity 0.1 UTN Chromium 0.0025Total Suspended Solids 0.5 Cobalt 0.00 1Total Dissolved Solids (180° C) 20 Copper 0.002Total Organic Carbon 0.5 Iron 0.02Dissolved Organic carbon 0.5 Lead 0.0005Total Kjeldahl Nitrogen 0.03 Manganese 0.002Nitrates and Nilrites 0.02 Molybdenum 0.002Ammonia 0.02 Nickel 0.002Total Phosphorus 0.002 Silver 0.0001Ortho Phosphates 0.002 Strontium 0.005Inorganic Phosphorus 0.002 Thallium 0.0001Reactive Silica 0.05 Tin 0.002Chlorophyll a and phytopigments 0.1 .tg/L Titanium 0.002Selenium (preconcentrated) 0.0001 Uranium 0.000 1
____________________________________ Vanadium 0.002
____________________________________ Zinc 0.002
IWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . February 12, 2000 Page 10
4.3.2 Chlorophyll
Subsurface water samples, comprising 1 L taken at 0.5 rn depth and 1 L taken from the 0-10 m depth
integrated sample, were collected and returned to the field lab, where particulate matter from tworeplicate 400 mL subsamples were passed through 4.25 cm Whatman GF/C filters. The extractedmaterial for chlorophyll analysis was then stored frozen prior to laboratory analysis (St. John's).
Analysis was by fluorometer with overnight 90% acetone extraction and with correction for
phaeopigments by acidification (Strickland and Parsons 1968).
Chlorophyll a and phaeopigment analysis was also conducted on the water samples submitted for lab
analysis.
4.3.3 Zooplankton Biomass
During both sampling campaigns, quantitative zooplankton samples were collected using a vertically
integrating tube sampler (Knoechel and Campbell 1992) fitted with a 100-jim mesh Nitex net. Fourreplicate samples, from 0 to 5-rn depth, were taken and combined to form a composite sample to
characterize the mixed surface layer. These were preserved with 95% ethanol for subsequent laboratory
analysis. Replicate composite samples were obtained at each station and analyzed in the laboratory (St.
John's). For each composite sample, a measured subsample sufficient to contain at least 100
crustaceans was examined under the dissecting microscope using phase contrast illumination.
Individual organisms were measured using an ocular grid and sorted into taxonomic categories (based
on size distribution). Individual biomass was calculated from published length-weight regressions,
accumulated in taxonomic categories, and then corrected for subsample volume and original sampled
volume (6.74 LIm) to yield an estimate of total zooplankton biomass (expressed as wet weight).
4.3.4 Zooplankton Mercury Body Burden
During the September sampling campaign, qualitative zooplankton samples were collected at each
station to provide five replicate bulk zooplankton samples (minimum 200 mg) for mercury body burdendetermination. The samples were obtained with a 200-jim mesh net to preclude as much phytoplankton
as possible. Alternatively, a 100-jim mesh net was used to obtain a bulk sample that was processed
through coarser meshes to remove phytoplankton. Bulk zooplankton was stored frozen in vials until
delivery to the laboratory at University du Québec a Montreal (UQAM). Blind duplicate samples
representing 10% of the total number of zooplankton samples collected were also submitted for mercury
determinations.
Water samples (filtered and non-filtered) were also analyzed for total mercury and methylmercury at the
UQAM laboratory.
JWEL Project 1218 LHP 1999 Water Quality & Chlorophyll Study Februaiy I 2, 2000 Page 11
5 RESULTS AND DISCUSSION
5.1 Field Measurements
The field measurements at each station during the two sampling campaigns are included in Appendix 1.Table 5.1 summarizes the field measurements to indicate the depth sampled, Secchi depth and the rangeof values for water temperature, dissolved oxygen, percent oxygen saturation, conductance and pH.
Table 5.1 Summary of Field Measurements During the Water Quality & Chlorophyll Study
Station
________________________
Date
__________
Depth(m)
Secchi(m)
Temp.(°C)
D.0.(mgIL)
02 Sat.(%)
Cond.(jts/cm)
pH(units)
Lac Joseph 1 Sep 99 63 4.0 9.9-14.9 7.8-8.8 73-92 14 6.2-6.9
AtikonakLake 1Sep99 9 4.1 14.9-15.1 8.9 93-94 13-14 7.0
Gabbro Lake 2Sep99 11.5 3.5 14.3-14.8 9.0-9.1 92-94 15 6.9
LobstickLake 2Sep99 16 3.4 14.3-14.9 8.6-8.9 88-92 18-19 7.1-7.2
Michikamau Lake 2 Sep 99 24 5.4 12.6-13.7 9.3-9.4 93-94 14 7.0-7.1
Wmokapau Lake 3 Sep 99 114 4.0 4.3-14.8 8.9-10.7 82-94 14-18 6.0-6.7
Gull Lake 3 Sep 99 13 3.8 16-9-17.2 9.2-9.4 96-98 17 7.1-7.2
Lac Joseph 5 Oct99 65 4.0 10.2-10.4 9.6-9.8 91-93 14-15 6.9-7.0
Atikonak Lake 5 Oct99 10.5 3.9 8.3-8.5 10.2-10.3 92-93 15 7.0-7.1
Gabbro Lake 5 Oct99 13 3.8 8.0 10.4-10.5 92-93 17 7.2
LobstickLake 6Oct99 16.5 2.8 7.4-7.7 10.4-10.5 91 18 7.1
MichikamauLake 6Oct99 26.5 4.5 8.4-8.7 10.3-10.4 92-93 14-15 7.1
WinokapauLake 8Oct99 66 4.0 4.8-9.7 10.1-10.3 81-90 15-19 6.3-7.0
Gull Lake 8 Oct 99 12 3.0 9.4 10.7 94 18 6.9-7.0
LEGEND: Depth is the depth to which sampling was conducted, Secchi depth is a measurement of water transparencyTemperature (Temp.), Dissolved Oxygen (DO.), Oxygen Saturation (02 Sat.), Conductance (Cond.)
Figure 5.1 illustrates the comparative water clarity based on the Secchi depths recorded for the twosampling campaigns in 1999 (dark bars) integrated on a seasonal basis with the results from 1998(lighter bars: JWEL 1999a).
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . February /2, 2000 Page 12
0 I- 0) CD
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epth
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5.1.1 Water Transparency
The Secchi depths observed in 1999 were generally consistent with those taken in September 1998(Figure 5.1) although there was a trend towards decreased transparency relative to 1998 in the lowerlakes (Lobstick Lake, Michikamau Lake, Winokapau Lake and Gull Lake). The seasonal trend of
declining Secchi depth observed in Lobstick and Michikamau in 1998 was confirmed by the 1999observations (Figure 5.1).
Churchill watershed Secchi depths ranged from 2.9-7.0 m, considerably greater than those reported for
the La Grande Reservoir complex where the mean Secchi for Opinaca was 2.1 m and for the Totostation in LG2 was 1.8-2.0 m (Pinel-Alloul 1991). A flooded river station at La Grande (station LG-2Amont) had Secchi depths of 2.3-2.8 m (Pinel-Alloul 1991) as compared to 3.0-4.9 m in LakeWinokapau and Gull Lake (Figure 5.1). Churchill watershed waters were also more transparent thanthose of Cat Arm Reservoir on the Great Northern Peninsula of insular Newfoundland which is
characterized by highly dystrophic (brown, humic coloured) waters with Secchi depths less than 2.0 m(Campbell et at. 1998), typically around 1.5 m. Southern Indian Lake, Manitoba displayed the widestvariation in light transmission which ranged from pre-impoundment levels of 3 7-59% m' at lakesampling sites to post-impoundment transmission as low as 4% m' due to severe shoreline erosion(values calculated from extinction coefficients reported in Table 2 of Hecky and Guildford 1984).
Churchill light transmission ranged from a low of 39.5% m1 to a high of 67.2% m' in 1998, with mostvalues above 50% m1 (reported in Appendix 3 of JWEL 1999a). Light transmission at Cat AnnReservoir is typically around 15 % m1. In summary, the Churchill River lakes exhibit greater watertransparency than each of the other three reservoir systems: La Grande, Southern Indian Lake and CatArm Reservoir.
5.1.2 Water Temperature
Mixed water column temperatures in 1999 (at 5 m depth) were generally higher than those observed onearlier sampling dates in 1998, suggesting a prolonged summer growing season in 1999 (Figure 5.2).
Deep thermoclines appeared to be present in Lac Joseph and Winokapau Lake in September and less soin Winokapau Lake in October (Figures 5.3 and 5.4). The detailed data in Appendix 1 shows a changeof 3 °C between 40-45 m depth in Lac Joseph in September. Similarly, in Winokapau Lake a 2.7 °Cchange was observed between 25-30 m depth and a 5.2 °C change was detected between 30-40 m depthin September. The largest change in temperature in October was a 1.8 °C change between 20 and 30 m
depth in Winokapau Lake. This is not a true thermocline, which is conventionally defined as a thermalgradient exceeding 1 °C m.
.JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . February 12, 2000 Page 14
Thus, with the exception of the September thermocline in two lakes, the water bodies appear wellmixed. The waters are well oxygenated, have quite low conductance, and are for the most part neutralor slightly acidic.
17-20 Aug98
1-2 Sep 99>-
0
24-26 Sep 98
5-6 Oct 99
0 5 10 15 20 25 30 35
Water Temperature (C)
Figure 5.2 Water Temperature Ranges for 1998 and 1999 Sampling Campaigns
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . Februaiy 12, 2000 Page 15
Figure 5.3 Lake Temperature Profiles - September 1999
18
17
16
15
14
13
(.)
a 12
a)
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10'U
9
8
7
6
5
4
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-46-- Atikonak
-A--Gabbro
-0-- Lobstick
Michikamau
-•-- Winokapau
Gull
0 20 40 60 80
Water Depth (m)
100 120
Figure 5.4 Lake Temperature Profiles - October 1999
18
17
16
15
14
13
0
w 12
ci)- 11
Eci)I.-
10
9
8
7
6
5
4
_____ -______ ---Joseph
-)(-- Atikonak
__________ ___________ __________________ ______ ______________________ -*-Gabbro
-0.-- Lobstick
_______-0-- Michikamau
-I--Winokapau
-1-Gull
0 20 40 60 80
Water Depth (m)
100
5.1.3 Field Lab Results
The results of the field lab analyses are contained in Appendix 2. The ranges observed for all stationsand campaigns combined were:
• pH 6.4-7.1• Conductivity 15-20 J.ts/cm• Oxygen concentration 8.4-11.5 mg!L• Alkalinity 4.1-8.2 mg!L• Bicarbonate 5-10 mg/L• Total inorganic carbon 1.3-3.9 mg/L
5.2 Water Quality
The analytical results for the water chemistry are contained in Appendix 3. Table 5.2 summarizes theresults for the two sampling campaigns for the seven lakes. The parameters are listed along with thelevel of quantitation (LOQ). The table lists the maximum, minimum and median concentrations foreach parameter and the number of samples analyzed. Median concentrations are given instead of meanconcentrations as many results were below the level of quantitation.
The water quality in the study lakes was typical of lakes found in the Precambrian shield - borealhabitat. The results are found to be quite similar to those determined for the Churchill River in 1998(JWEL 1 999b). The waters are very dilute, being neutral to slightly acidic with low levels of dissolvedsolids, dissolved organic carbon and specific conductance. Nutrient concentrations hosphorous andnitrogen compounds) were also very low indicating low potential productivity. In 1998, there was an
indication of slight increases in aluminum, silica and turbidity in downstream stations along theChurchill River. This was not evident in the lake sampling program of this study.
These water characteristics are also similar to those reported in waters from lakes and rivers located inthe eastern part of the La Grande complex (Environnement illimitée inc. 1997) or on the North Shore ofthe St-Lawrence River (Robertson Reservoir area: Doyon and Dussault, 1998, Moisie River area:Garceau and Marquis 1991).
.JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 18
Table 5.2 Summary of Water Chemistry for Sampling in September-October 1999
Parameter LOQ Units N Maximum Minimum Median Mean s.d.Thlorophyll a 0.1 pg/L 14 3.6 0.8 1.7 1.8 0.8haeopigments 0.1 pgIL 14 1.0 0.0 0.4 0.5 0.2
DOC 0.5 mgIL 15 4.2 1.6 3.4 3.2 0.6DC 0.5 mg!L 16 7.4 1.8 3.7 3.8 1.2DS (180 Deg) 20 mgIL 14 33 <20 21 na. na.
'SS 0.5 mgIL 14 1.9 0.6 0.9 1.0 0.4'rue Colour I UCV 14 30 7 26 24 7urbidity 0.2 UTN 14 1.0 <0.2 0.5 n.a. n.a.
Sulphide 0.02 mgIL 3 <0.02 <0.02 <0.02 na. na.Lmmonia 0.02 mgN/L 16 0.04 0.02 0.02 0.02 0.01
Reactive Phosphorous 0.002 mg PIL 16 0.008 0.002 0.004 0.004 0.001)rtho-Phosphates 0.002 mgPIL 16 0.004 <0.002 <0.002 n.a. n.a.Reactive Silica 0.05 mg SiO2IL 14 3.03 0.45 2.23 1.95 0.89fotal Phosphorous 0.002 mg PIL 16 0.008 <0.002 0.005 n.a. n.a.fannins 0.1 mgIL 14 0.9 0.3 0.7 0.7 0.2I'KN 0.03 mgNIL 16 0.18 <0.03 0.14 na. n.a.ihloride 0.2 mg CIIL 16 0.5 <0.2 0.1 na. n.a.Nitrates & Nitrites 0.02 mg NIL 16 0.04 <0.02 <0.02 n.a. n.a.Sulphate 0.5 mgSO4IL 16 1.3 0.7 0.9 0.9 0.2Selenium 0.0001 mgIL 16 0.0002 <0.0001 0.0001 n.a. n.a.
alcium 0.1 mgIL 16 3.4 1.4 1.8 1.9 0.6Magnesium 0.01 mgIL 16 0.71 0.34 0.43 0.48 0.12Sodium 0.02 mgIL 16 0.44 0.32 0.38 0.39 0.04Potassium 0.02 mgIL 16 0.27 0.16 0.22 0.21 0.03Iron 0.02 mgIL 16 0.16 0.02 0.09 0.09 0.04\luminum 0.010 mgIL 15 0.520 <0.010 0.030 n.a. n.a.thtimony 0.002 mgIL 16 <0.002 <0.002 <0.002 n.a. n.a.rsenic 0.002 mgIL 16 <0.002 <0.002 <0.002 n.a. n.a.
Barium 0.005 mgIL 16 0.060 <0.005 0.006 n.a. n.a.Beryllium 0.005 mgIL 16 <0.005 <0.005 <0.005 n.a. n.a.Bismuth 0.002 mgIL 16 <0.002 <0.002 <0.002 n.a. na.loron 0.005 mgIL 16 <0.005 <0.005 <0.005 na. n.a.admium 0.0001 mgIL 16 0.0360 <0.0001 <0.0001 na. na.
Thromium 0.002 mgIL 16 0.003 <0.002 <0.002 na. n.a.cobalt 0.001 mgIL 16 <0.001 <0.001 <0.001 n.a. na.copper 0.002 mgIL 16 0.004 <0.002 <0.002 n.a. na.
Lead 0.0005 mgIL 16 0.0007 <0.0005 <0.0005 n.a. n.a.ilanganese 0.002 mgIL 16 0.110 0.006 0.010 0.019 0.025ilolybdenum 0.002 mgIL 16 0.000 <0.002 <0.002 n.a. na.4ickel 0.002 mgIL 16 0.022 <0.002 <0.002 n.a. n.a.
Silver 0.0001 mgIL 16 <0.0001 <0.0001 <0.0001 na. n.a.Strontium 0.005 mgIL 16 0.034 0.008 0.012 0.013 0.006Thallium 0.0001 mgIL 16 <0.0001 <0.0001 <0.0001 n.a. n.a.'in 0.002 mgIL 16 <0.002 <0.002 <0.002 n.a. n.a.'itanium 0.002 mgIL 16 0.007 <0.002 <0.002 na. na.
Uranium 0.0001 mgIL 16 <0.0001 <0.0001 <0.0001 n.a. n.a.Ianadium 0.002 mgIL 16 <0.002 <0.002 <0.002 n.a. n.a.inc 0.002 mgIL 16 0.017 <0.002 0.002 n.a. n.a.dotes:
s.d. standard deviation
n.a. not applicable - where some or all of the data set are not quantified values
.JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 19
5.3 Chlorophyll
The results of the chlorophyll analyses in the St. John's lab are presented in Appendix 4. The mean
concentration from all samples collected at any station was used to plot chlorophyll concentrations inFigure 5.5. Chlorophyll concentrations are also included in the water sample analysis in Appendix 3.
There was a general trend of increasing chlorophyll concentration throughout the growing season at thelentic, lake sampling sites (Figure5.4) as compared to a declining seasonal trend at the lotic, flowingsites (Winokapau and Gull).
Chlorophyll concentrations in September-October 1999 were generally comparable to or higher thanthose observed in September 1998, consistent with the extended growing season hypothesized above(see Figure 5.2). The largest differences were in Lobstick Lake and Lake Winokapau where the 1999concentrations were 69% and 54% greater than in 1998 respectively. These higher chlorophyllconcentrations are consistent with the previously noted lower Secchi transparencies for those two lakes(Figure 5.1) and the generally warmer temperatures indicative of a longer growing season (Figure 5.2).
Chlorophyll concentrations in both years were generally between 1-2 mg Chl m with the exception ofLobstick Lake, which exceeded 3.5 mg m3 on both sampling dates in 1999. These levels exceed theranges observed at La Grande LG-2 (0.66-1.30) and Opinaca (0.87-1.14) stations in Quebec (Pinel-Alloul 1991) but are below those observed at the lentic stations in Southern Indian Lake, Manitoba bothpre-impoundment and post-impoundment (range 1.8-5.9 mg m3 at stations 1-5, Hecky and Guildford1984). Chlorophyll data are not available for Cat Arm Reservoir.
5.4 Phytoplankton Composition and Biomass
The phytoplankton communities in the Churchill watershed are dominated by small nanoplankton with
maximum dimension less than 30 pm (JWEL 1999a), similar to those at Cat Arm Reservoir (Copeman
and (noechel 1996). The phytoplankton conmriunities in La Grande reservoirs LG-2 and Opinaca havebeen reported to be also dominated by small microflagellates and chrysophytes (Pinel-Alloul 1991)unlike those in Southern Indian Lake where diatoms and filamentous blue-green algae were frequentsummer dominants (Table 1 in Planas and Hecky 1984). These latter groups are characteristic of moreproductive systems.
Mean phytoplankton biomass in the lentic water bodies of the Churchill watershed ranged fromapproximately 200-500 mg m3 in 1998 (see Figure 6.15 in JWEL 1999a). This was about the samerange observed in post-impoundment Cat Arm Reservoir (see Figure 7.5 in JWEL 1999a) and in the LaGrande complex (Thérien et al. 1982, Morrison and Thérien 1987). These levels were generallyexceeded in Southern Indian Lake where a range of 291-7298 mg m3 was observed in July andSeptember 1976 (Planas and Hecky 1984), consistent with the higher chlorophyll levels noted above for
.JWEL Project 1218 . LHP 1999 Water Quality & Chlorophyll Study February 12, 2000 Page 20
the Manitoba system. Duthie and Ostrofsky (1974) reported 1970 seasonal maximum phytoplanktonbiomass levels ranging from 80-739 mg m3 in lakes in the Churchill watershed ranging from Atikonak
Lake down to Flour Lake. A narrower range of seasonal maxima was observed in 1998 with valuesfrom 46 1-676 mg m3 reported for the same areas (JWEL 1999a).
5.5 Primary Production
Areal primary production rates in the Churchill watershed averaged approximately 100 mg C m2 d1 in1998 (Figure 6.8 in JWEL 1999a, using a factor of 10 to convert hourly values to daily estimates).These rates are comparable to or slightly less than the reported pre-impoundment rates of 100-200 mg Cm2 d' (Duthie and Ostrofsky 1975; see Figure 7.2 in JWEL 1999a for a graphic comparison). Currentproduction rates exceed both pre-impoundment and post-impoundment levels observed in Cat ArmReservoir where summer rates ranged from approximately 30-70 mg C m2 d1 (Campbell et cii. 1998,using a factor of 10 to convert hourly rates to daily estimates). The low production rates in Cat ArmReservoir are related to the much lower water transparency (noted above) which leads to a very shallowphotosynthetic zone.
Churchill primary production was much lower than both pre-impoundment and post-impoundmentprimary production in Southern Indian Lake where seasonal means of 3 10-710 mg C m2 d' werereported for several lake stations from 1974-1978 (Hecky and Guildford 1984). The lower rates at
Churchill can be attributed in part to the lower chlorophyll levels (see above) but are also indicative oflower rates of specific production which suggests a greater level of nutrient stress. Maximum hourlyrate of specific production (mg C mg Chi') in the Churchill watershed declined from approximately 3.5in mid-July 1998 to 2.5 in mid-August and <2.0 in late September (Figures 6.9, 6.10 and 6.11 in JWEL1999a). The seasonal mean rates reported for the July to early September period in Southern IndianLake were generally higher, ranging from 2.2-4.5 but with most values > 3.0. Thus the northernManitoba system had a higher standing crop (chlorophyll) with a higher level of physiological activity(specific production).
The Churchill areal production rates are comparable to the rates reported for the control stations in the
La Grande LG-2 and Opinaca regions where rates ranged from approximately 60-250 mg C m2 d'(calculated by dividing the annual rates reported in Table 5 of Roy et al. 1986 by an estimated 120-daygrowing season). This implies that the La Grande phytoplankton community had a higher rate ofspecific production than Churchill did, given that comparable total production was achieved despitelower chlorophyll levels (see above). Post-impoundment production rates in flooded areas of LG-2(Bereziuk) and Opinaca approximately doubled, ranging from 175-610 mg C m2 d1 (calculated fromTable 5 in Roy et at. 1986). These levels are comparable to those noted above for Southern Indian Lake.
.JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . February 12, 2000 Page 21
5.6 Zooplankton Biomass
The total zooplankton biomass in September-October 1999 was comparable to that measured inSeptember 1998 in Lac Joseph, Atikonak, Winokapau and Gull lakes (Figure 5.5). In contrast, totalzooplankton biomass was much greater than September 1998 levels in Lobstick, Gabbro andMichikamau lakes. Total zooplankton biomass in the latter two lakes, while much higher thanSeptember 1998, was nevertheless lower than the peak levels observed in 1998 for each site. This maysimply reflect a longer growing season in 1999; water temperatures in October 1999 exceeded thosemeasured in September 1998 (Figure 5.2) when both lakes exhibited sharp declines in zooplanktonbiomass. The Lobstick Lake zooplankton biomass levels in 1999 far exceeded all values observed in1998. Such high levels are consistent, however, with the observation that chlorophyll levels in Lobstickin 1999 were also much higher than in 1998 (Figure 5.4); higher chlorophyll levels should supporthigher zooplankton biomass.
Zooplankton biomass in the Churchill watershed lakes was dominated by cladocerans followed bycalanoid copepods (Figure 5.5), comparable to the communities observed in the La Grand Reservoircomplex (Roy 1985, Méthot and Pinel-Alloul 1987) and Cat Arm Reservoir (Campbell et al. 1998).Biomass concentrations at Churchill watershed lake stations ranged from 16-5 16 mg m3 with mostvalues in the 100-300 mg m3 range (Figure 5.5). These levels are comparable to pre-impoundmentbiomass levels at La Grande where seasonal means of 178 mg m3 were reported for Bereziuk and 327mg m3 for Toto (Roy 1985; using a dry weight to wet weight conversion factor of 10 from Dumont etal. 1975 and Bottrell et al. 1976) but lower than the 400-600 mg m3 range observed in post-impoundment Cat Arm Reservoir (see Figure 7.5 in JWEL 1999a).
La Grande biomass levels increased several fold following impoundment (lentic sites) but returned tonear the original levels by the 6th year of impoundment. Cat Arm Reservoir zooplankton biomassremains elevated; the original Cat Arm Lake had such a high flushing rate that its low zooplankton levelwas similar to that in rivers.
Quantitative comparisons with biomass levels at Southern Indian Lake caimot be readily made becausedata were reported as densities (Patalas and Salki 1984). It is nevertheless clear that the Southern IndianLake community composition was quite different, with the pre-impoundment crustacean communitydominated by cyclopoid copepods followed by calanoids and then cladocera. The crustaceancommunity in post-impoundment Southern Indian Lake was co-dominated by calanoids and cyclopoidswith the cladoceran component much-reduced (Patalas and Salki 1984). There was approximately a45% decline in crustacean zooplankton densities following impoundment, unlike La Grande and CatArm where density and biomass increased. Patalas and Salki (1984) attributed the decline to a 2-3 °Cdrop in the water temperature, which reduced growth rates by 20% and crustacean production by 60%.The decline is contrary to the expectation of zooplankton increase following impoundment, whichreduces flushing rates and associated washout losses. This may be because Southern Indian Lake was alarge system prior to impoundment which only increased surface area by 21% with relatively modestflushing rate decreases (Hecky et al. 1984).
JWEL Project 1218 LHP 1999 Water Quality & Chlorophyll Study Februaiy 12, 2000 Page 22
Chl
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Figure 5.6 Zooplankton Biomass - July-September 1998 and September-October 1999
50
450
400
350
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DRotifers
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5.7 Mercury Concentrations in Water and Zooplankton
Mercury and methylmercury concentrations were investigated in water and zooplankton for all of thestudy lakes. The methods used for analysis were the same as has been done for Hydro-Quebec in thepast. Total Hg and MeHg concentrations in zooplankton and in water samples were measured by coldvapour atomic fluorescence spectrophotometry (Plourde et at. 1997; Tremblay and Lucotte 1997).Appendix 6 contains the report from UQAM.
Total mercury concentrations in filtered water samples varied from 0.32 to 1.23 ng/L while in non-filtered samples had values ranging from 0.44 to 1.22 ng/L (Figure 5.7). The differences between themercury concentration of the filtered and unfiltered water samples are not significant and it was noted by
UQAM that there were very little suspended particles in the unfiltered water samples (see: Section 6.2 inAppendix 6). These concentrations are similar to those measured in waters flowing out of theCaniapiscau Reservoir, 15 years after the impoundment (filtered samples: 0.97 to 1.43 ng/L; non-filteredsamples: 1.19 to 1.69 ng!L, Schetagne et at. In press). Other works at La Grande also reported totalmercury values of 1.5 ng!L in filtered samples (Montgomery et at. 1995).
None of the water samples had detectable (0.041 ng Hg/L) concentrations of methylmercury.
Methylmercury concentrations measured in waters coming out of the Caniapiscau reservoir, 15 years
after flooding were higher than this study with values ranging from 0.046 to 0.093 ng/L (Schetagne et at.In press). A study carried out at the La Grande complex by Montgomery et at. (1995) reportedmethylmercury levels of 0.OSng/L in the area of the Robert-Bourassa and Laforge 1 reservoirs.
Mean methylmercury concentrations in zooplankton collected in 1999 in the Churchill River system
ranged from 2 to 72 ng!g (dry weight) while in the Caniapiscau Reservoir, mean values of 86 nglg werereported 15 years after flooding (1997, Schetagne et at. In press). In natural lakes located at the LaGrande complex, methylmercury concentrations ranging from 50 to 150 ng!g were recorded by Plourdeset at: (1997). Total mercury concentrations in plankton collected from the Churchill River system in1999 ranged from 68 to 260 ng!g. Corresponding values for the Caniapiscau Reservoir averaged132 ng/g (Schetagne et at. In press). Plourdes et at. (1997) found that methylmercury in natural lakesrepresented on average 33% of the total mercury concentration.
Figure 5.8 shows the concentrations of total mercury and methylmercury determined for zooplankton inthe seven lakes.
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study February 12, 2000 Page 25
C-
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Figure 5.8 Mercury Concentration in Zooplankton
300
TotaI Mercury9 Methylmercury
250
200
C)C)
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00
100
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Joseph Atikonak Gabbro Lobstick Michikamau Winokapau Gull
Lake
6 CONCLUSIONS
The water and chlorophyll study was conducted over a large area over two campaigns and the results aresimilar enough to data gathered in Newfoundland, Quebec and Manitoba to relate predictions forChurchill River to modelling based on the extensive databases for the other locations. More frequentsampling would help quantify and place temporal benchmarks on high and low production periods - butthese will vary somewhat from year to year anyway. A comparison between the 1998 and 1999 dataindicates similar patterns that are shifted slightly in time. Winter season sampling would determine thesimilarities between systems for the lengthy non-productiveT cold season - however this is not critical tomodelling the results of the propose project.
Studies of plankton communities following initial impoundment of the Smallwood Reservoir inLabrador (Ostrofsky and Duthie 1980) and the La Grande complex in Quebec (Pinel-Alloul 1991) haveboth revealed a trophic upsurge associated with the release of nutrients, particularly phosphorus, fromflooded soils and drowned vegetation. The nutrient release leads to enhanced levels of primaryproductivity plus increased phytoplankton biomass. There were substantial increases in zooplanktonbiomass following impoundment at La Grande, likely due to a combination of increased food supply and
reduced washout losses; increases were greatest in formerly fluvial areas (Méthot and Pinel-Alloul 1987,Roy 1985). Conditions returned to approximately starting levels in the 6th year of flooding at La Grande(Roy 1985); there are not sufficient data to document the time course of zooplankton change in theSmallwood Reservoir.
Post-impoundment plankton dynamics were considerably different in Southern Indian Lake, Manitoba.
Flooded soils at Southern Indian Lake did result in elevated nutrient levels but with only a brief pulse ofincreased primary productivity (Jackson and Hecky 1980). The nutrient release was rapidly followed byan increase in dissolved humic substances, which were believed to have depressed primary production
through sequestering iron and other essential micronutrients rendering them unavailable to thephytoplankton (Jackson and Hecky 1980). Greatly increased turbidity also led to increased lightlimitation of photosynthesis (Hecky and Guildford 1984). Subsequent studies of phosphorus dynamicsrevealed that Southern Indian Lake phytoplankton communities, as well as some of those in nearbynatural lakes, were not phosphorus limited (Planas and Hecky 1984). The observed lack of phosphorus
limitation is consistent with the lack of 'trophic upsurge' following phosphorus release from the floodedsoils; some other nutrient was limiting the production of new biomass. Impoundment of SouthernIndian Lake resulted in an unexpected decline in crustacean zooplankton biomass, which was associatedwith reduced water temperatures attributed to greater lake volume, and increased lake albedo(reflectance). The reduced lake temperature caused a reduction in zooplankton growth and productionin the absence of phytoplankton enhancement.
Post-impoundment plankton dynamics in the Cat Arm Reservoir on the Great Northern Peninsula ofinsular Newfoundland reflect the same processes observed in the Smaliwood, La Grande and SouthernIndian Lake systems but in a unique setting. Total phosphorus and inorganic phosphate levels did
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . Februaty 12, 2000 Page 28
initially increase following impoundment of Cat Arm Reservoir, consistent with the trophic upsurgeparadigm, but total nitrogen declined and nitrate levels quickly dropped below the limits of detection(Campbell et al. 1998, Copeman and Knoechel 1996). Primary production rates did not increase in thefirst few years of impoundment, presumably due to the lack of nitrogen. Nitrogen addition in a mid-summer bioassay produced a large increase in net primary production as compared to a minimalresponse to phosphorus addition. Phytoplankton biomass generally declined during the first five years
of impoundment, likely due in part to the 19-fold increase in zooplankton biomass, which was attributedto the higher water retention time, and concomitant decrease in washout losses (Campbell et al. 1998).
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study . Februaty 12, 2000 Page 29
7 REFERENCES
Botrell, H.H., A. Duncan, Z.M. Gliwicz, E. Grygierek, A. Herzig, A. Hillbricht-Ilkowska, H. Kurasawa,P. Larsson and T. Weglenska. 1976. A review of some problems in zooplankton productionstudies. Norw. J. Zool. 24:419-456.
Campbell, C.E., R. Knoechel and D. Copeman. 1998. Evaluation of factors related to increasedzooplankton biomass and altered species composition following impoundment of aNewfoundland reservoir. Can. J. Fish. Aquat. Sci. 55: 230-238.
Copeman, D. and R. Knoechel. 1996. Trophic evolution of Cat Arm reservoir: 1993, the ninth year atfull supply level. Report to Newfoundland and Labrador Hydro. 28 pp.
Doyon, J-F. and D. Dussault. 1998. Environmental monitoring of the Robertson reservoir (1997).
Evolution of water quality, fish communities and mercury. Report prepared by Génivar forHydro-Québec, Direction projets de distribution, 76 p and appendices.
Dumont, H.J., I van de Velde and S. Dumont. 1975. The dry weight estimate of biomass in a selectionof Cladocera, Copepoda and Rotifera from the plankton, periphyton and benthos of continentalwaters. Oecologia 19:75-97.
Duthie, H.C. and M.L. Ostrofsky. 1974. Plankton, Chemistry and Physics of Lakes in the ChurchillFalls region of Labrador. J. Fish. Res. Bd. Can. 31: 1105-1117.
Duthie, H.C. and M.L. Ostrofsky. 1975. Environmental impact of the Churchill Falls (Labrador)hydroelectric project: a preliminary assessment. S. Fish. Res. Board. Can. 32: 117-125.
Environnement Illimitée Inc. 1997. Suivi des milieux aquatiques de la region de Laforge-2 (1997)-Suivi
de la qualité de l'eau, poissons et mercure. Rapport présenté a la direction Ingénierie et- Environnement de la Société d'énergie de la Baie James. 71 p. et annexes.
Garceau, C. and H. Marquis. 1991. Projet Sainte-Marguerite- Caractérisation physico-chimique des eauxde la rivière moisie et de ses principaux affluents et repercussions du détournement des rivièresaux Pékans et Carheil. Rapport présenté a la Vice-présidence environnement, Hydro-Quebec,par le Groupe Environnement Shooner inc. 99 p. et annexes.
Hecky, R.E. and S.J. Guildford. 1984. Primary productivity of Southern Indian Lake before, during, andafter impoundment and Churchill River diversion. Can. S. Fish. Aquat. Sci. 41: 591-604.
JWEL Project 1218 • LHP 1999 Water Quality & Chlorophyll Study Februaty 12, 2000 Page 30
Hecky, R.E., R.W. Newbury, R.A. Bodaly, K. Patalas and D.M. Rosenberg. 1984. Environmentalimpact prediction and assessment: the Southern Indian Lake experience. Can. J. Fish. Aquat. Sci.41:720-732.
Jackson, T.A. and R.E. Hecky. 1980. Depression of primary productivity by humic matter in lake andreservoir waters of the boreal forest zone. Can. J. Fish. Aquat. Sci. 37:2300-23 17.
Jacques Whitford Environment Limited. 1 999a. Primary Productivity and Plankton Biomass (LHP 98-10). Report prepared for Labrador Hydro Project, St. John's, Newfoundland. 62 pp + app.
Jacques Whitford Environment Limited. 1 999b. Water and Sediment Quality of the Churchill River(LHIP 98-08). Report prepared for Labrador Hydro Project, St. John's, Newfoundland. 85 pp +app.
Knoechel, R. and C.E. Campbell. 1992. A simple, inexpensive device for obtaining verticallyintegrated, quantitative samples of pelagic zooplankton. Linmol. Oceanogr. 37: 675-680.
Méthot, G. and B. Pinel-Alloul. 1987. Fluctuations du zooplancton dans le reservoir LG-2 (Baie James,
Québec): relation avec Ia qualite physico-chimique et trophique des eaux. Le Naturalistecanadien, 114 : 369-379.
Montgomery 5, A. Mucci, M. Lucotte and P. Pichet. 1995. Total dissolved mercury in the water columnof several natural and artificial aquatic systems of northern Quebec (Canada). Can. J. Fish.Aquat. Sci. 52: 2483-2492.
Morrison, K.A. and N. Thérien. 1987. Importance de la consideration des effets convectifs par lesmodèles prévisionnels de la dynamique du plancton. Le Naturaliste canadien, 114: 38 1-388.
Ostrofsky, M.L. and H.C. Duthie. 1980. Trophic upsurge and the relationship between phytoplanktonbiomass and productivity in Smallwood Reservoir, Canada. Can. J. Bot. 58: 1174-1180.
Patalas, K. and A. Salki. 1984. Effects of impoundment and diversion of the crustacean plankton ofSouthern Indian Lake. Can. J. Fish. Aquat. Sci. 41:613-637.
Pinel-Alloul, B. 1991. Annual variations of the phytoplankton community during impoundment ofCanadian subarctic reservoirs. Verh. internat. Verein. Limnol., 24: 1282-1287.
Planas, D. and R. E. Hecky. 1984. Comparison of phosphorus turnover times in northern Manitobareservoirs with lakes of the Experimental Lakes Area. Can. J. Fish. Aquat. Sci. 41:605-612.
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Plourde Y, M. Lucotte and P. Pichet. 1997. Contribution of suspended particulate matter andzooplankton to MeHg contamination of the food chain in midnorthem Quebec (Canada)reservoirs. Can. J. Fish. Aquat. Sci. 54: 821-83 1.
Roy, D. 1985. Réseau de surveillance écologique du Complexe La Grande 1978-1984: Zooplankton.Société d'énergie de la Baie James, Montréal. 83 p. and appendices.
Roy, D., M. Laperie, J. Boudreault, R. Boucher, R. Schetagne and N. Thérien. 1986. Ecological
monitoring program of the La Grande complex 1978-1984; summary report. Société d'énergie dela Baie James, Montréal. 62 p. and appendices.
Schetagne, R. J-F. Doyon and J-J. Foumier. In Press. Export of mercury downstream from reservoirs.Science of The Total Environment 00: 000-000.
Somer Inc., and J-L. Fréchette. 1992. Guide méthodologiques des relevés de la qualité deléau. Rapportpresénté a Hydro-Quebec, vice-présidence Environnement. Montréal, Québec. 79 pp + 10annexes.
Strickland, J.D.H. and T.R. Parsons. 1968. A Practical Handbook of Seawater Analysis. Fish. Res.Board Can. Bull.
Thérien, N., K. Morrison, M. de Broissia and B. Marcos. 1982. A simulation model of planktondynamics in reservoirs of the La Grande River complex. Le Naturaliste canadien, 109: 869-881.
Tremblay A and M. Lucotte. 1997. Accumulation of total mercury and methylmercury in insect larvaeof hydroelectric reservoirs. Can. J. Fish. Aquat. Sci.; 54: 832-841.
JWEL Project 1218 LHP 1999 Water Quality & Chlorophyll Study February 12, 2000 Page 32
APPENDIX 1
1999 Water Quality and Chlorophyll StudyField Measurements
APPENDIX 1 - 1999 Water Quality and Chlorophyll Study - Field Measurements
LEGEND
Table for Water Sampling Stations (Sites)
Station: Identifier for sample identification and database entry
Lake: Name of the lake sampled
Date/Time: Date and time (Atlantic Time) of sampling
Transparency: Determined with a Secchi disk
Colour: Determined with a Secchi disk
Replicat.: Replicates indicates stations where 3 subsamples were taken to check for the reliability ofPhilip (PSC) analysis
Blind Sample: Blind samples indicate stations where an unidentified (fantôme) sample was sent toPhilip Lab. In results, no 6-90 (used by the lab) stands for the last no of station CHO16,and for sample 90
Remark: Comments on depth at station and samples collected
APPENDIX 1: 1999 Water Quality and Chlorophyll Study - Field Measurements (Site Information)
Station Lake Date Time Transparency Colour Replicat. Blind Remaris(AST) (m) Sample
CH01I Lac Joseph 01/09/99 9:45 4.0 B Bottom at 64 mCHO12 Atikonak Lake 01/09/99 14:15 4.1 B Bottom at 10 m Ortho-P Redone (broken bottle)CHO13 Gabbro Lake 02/09/99 15:05 3.5 B Bottom at 12.7 mCHO14 Lobstick Lake 02/09/99 12:45 3.4 B Bottom at 17 mCHO15 Michikamau Lake 02/09/99 9:20 5.4 A Bottom at25 mCHOI6 Winokapau Lake 03/09/99 11:30 4.0 B 6-90 6-90 Bottom at 115 m R1-R2CHO17 Gull Lake 03/09/99 15:00 3.8 B Bottom at 14 mCH011 LacJoseph 05/10/99 10:15 4.0 B Bottom at 66mCHO12 Atikonak Lake 05/10/99 13:15 3.9 B Bottom at 11.5 R1-R2 Blind HgCHO13 Gabbro Lake 05/10/99 15:30 3.8 B Bottom at 14 mCHO14 Lobstick Lake 06/10/99 11:20 2.8 B 4 4 Bottom at 17.5 R1-R2 Blind Quality H20CHO15 Michikamau Lake 06/10/99 15:25 4.5 A Bottom at 27.5CHO16 Winokapau Lake 08/10/99 14:15 4.0 B Bottom at 67 mCHO17 Gull Lake 08/10/99 16:20 3.0 B Bottom at 13 m
COLOR: A = greenish brown; B = humic brown
APPENDIX 1 - 1999 Water Quality and Chlorophyll Study - Field Measurements
LEGEND
Table for Water Quality Profiles
Date: Date of sampling
Station: Lake sampled
Sample: Sample number assigned to each depth where data was recorded#90 integrated water sample from the surface to 10 m (meter readings averaged)#91 bottom sample collected at 1 m above the bottom
Depth: Depth of water sampled in metres
Temperature: Water temperature determined by (C 10) HYDROLAB Surveyer II
Dissolved OxygenlSaturation: Determined by (C 10) HYDROLAB
Conductivity: Determined by (C 10) HYDROLAB
pH: Determined by (C 10) HYDROLAB
Validat. PH: pH of selected samples determined by (C30) Hannah pH meter for validation ofHYDROLAB
Replicat.: Replicates indicates stations where 3 subsamples were taken to check for the reliabilityof Philip (PSC) analysis
Sample ID: Sample identification for sample submitted to PSC
Remark: Comments on analysis of samples
Page 1
APPENDIX 1: 1999 Water Qual ity and Chlorophyll Study - Field Measurements (Water Quality Profiles)
Date Station Sample Depth Temp. Dissolved 02 Conductivity pH Validat. Replicat. Sample Remarks(m) (°C) Oxygen Saturat. (p5/cm) pH ID
(mgIL) (%) (PSC)C10 dO dO dO C30
01/09/99 LJoseph 1 1.0 14.9 8.8 92 14 6.901/09/99 L Joseph 2 2.0 14.9 8.8 92 14 6.8 6.6 1-90 trace metals01/09/99 L Joseph 3 3.0 14.9 8.8 92 14 6.801/09/99 L Joseph 4 4.0 14.9 8.8 92 14 6.801/09/99 L Joseph 5 5.0 14.9 8.8 92 14 6.801/09/99 L Joseph 6 6.0 14.9 8.8 92 14 6.801/09/99 L Joseph 7 7.0 14.9 8.8 92 14 6.801/09/99 L Joseph 8 8.0 14.8 8.8 92 14 6.801/09/99 L Joseph 9 9.0 14.8 8.8 92 14 6.801/09/99 L Joseph 10 10.0 14.7 8.8 92 14 6.8 6.801/09/99 LJoseph 11 15.0 14.7 8.8 92 14 6.801/09/99 L Joseph 12 20.0 14.7 8.8 92 14 6.801/09/99 L Joseph 13 30.0 14.7 8.7 91 14 6.701/09/99 L Joseph 14 35.0 14.6 8.8 92 14 6.701/09/99 L Joseph 15 40.0 14.2 8.6 89 14 6.701/09/99 LJoseph 16 45.0 11.2 7.8 75 14 6.301/09/99 L Joseph 17 50.0 10.5 7.8 74 14 6.301/09/99 L Joseph 18 60.0 10.2 7.8 73 14 6.201/09/99 L Joseph 90 10.0 14.9 8.8 92 1-90
01/09/99 L Joseph 91 63.0 9.9 7.8 73 14 6.2 6.3 1-91
01/09/99 Atikonak L 1 1.0 15.1 8.9 94 14 7.001/09/99 Atikonak L 2 2.0 15.0 8.9 93 14 7.0 6.9 2-90 trace metals
01/09/99 Atikonak L 3 3.0 15.0 8.9 93 13 7.001/09/99 Atikonak L 4 4.0 15.0 8.9 93 13 7.001/09/99 Atikonak L 5 5.0 15.0 8.9 93 14 7.001/09/99 Atikonak L 6 6.0 15.0 8.9 93 14 7.0 7.001/09/99 Atikonak L 7 7.0 15.0 8.9 93 14 7.0
01/09/99 Atikoriak L 8 8.0 15.0 8.9 93 13 7.0
01/09/99 Atikonak L 90 9.0 15.0 8.9 93 2-90
01/09/99 Atikonak L 91 9.0 14.9 8.9 93 14 7.0 7.0
02/09/99 Gabbro L 1 1.0 14.8 9.0 93 15 7.0
02/09/99 Gabbro L 2 2.0 14.7 9.0 93 15 6.9 7.0 3-90 trace metals
02/09/99 Gabbro L 3 3.0 14.7 9.0 93 15 6.902/09/99 Gabbro L 4 4.0 14.7 9.1 94 15 6.902/09/99 Gabbro L 5 5.0 14.7 9.1 94 15 6.902/09/99 Gabbro L 6 6.0 14.7 9.0 93 15 6.902/09/99 Gabbro L 7 7.0 14.7 9.0 93 15 6.902/09/99 Gabbro L 8 8.0 14.6 9.0 93 15 6.9
02/09/99 Gabbro L 9 9.0 14.6 9.0 93 15 6.9
02/09/99 Gabbro L 10 10.0 14.5 9.0 93 15 6.9
02/09/99 Gabbro L 11 11.0 14.4 9.0 92 15 6.902/09/99 Gabbro L 12 12.0 14.3 9.0 92 15 6.902/09/99 Gabbro L 90 10.0 14.7 9.0 93 3-90
02/09/99 Gabbro L 91 11.5 14.4 9.0 92 15 6.9 6.9
Page 2
Date Station Sample Depth Temp. Dissolved 02 Conductivity pH Validat. Replicat. Sample Remarks(m) (°C) Oxygen Saturat. (PS/cm) pH ID
(mgIL) (%) (PSC)C10 dO dO dO C30
02/09/99 Lobstick L 1 1.0 14.9 8.8 91 18 7.2
02/09/99 Lobstick L 2 2.0 14.8 8.8 91 19 7.1 7.1 4-90 trace metals
02/09/99 LobstickL 3 3.0 14.7 8.9 92 18 7.2
02/09/99 Lobstick L 4 4.0 14.7 8.9 92 18 7.202/09/99 Lobstick L 5 5.0 14.7 8.9 92 18 7.2
02/09/99 Lobstick L 6 6.0 14.7 8.9 92 19 7.1
02/09/99 Lobstick L 7 7.0 14.7 8.9 92 19 7.1
02/09/99 Lobstick L 8 8.0 14.6 8.8 91 19 7.1
02/09/99 Lobstick L 9 9.0 14.6 8.8 91 19 7.1
02/09/99 Lobstick L 10 10.0 14.5 8.7 89 19 7.1
02/09/99 Lobstick L 11 13.0 14.4 8.7 89 19 7.1
02/09/99 Lobstick L 90 10.0 14.7 8.8 91 4-90
02/09/99 Lobstick L 91 16.0 14.3 8.6 88 18 7.1 7.0
02/09/99 Michikamau L 1 1.0 13.7 9.3 94 14 7.1
02/09/99 Michikamau L 2 2.0 13.7 9.3 94 14 7.1 7.2 5-90 trace metals
02/09/99 Michikamau L 3 3.0 13.6 9.3 94 14 7.1
02/09/99 Michikamau L 4 4.0 13.6 9.3 94 14 7.1
02/09/99 Michikamau L 5 5.0 13.5 9.3 94 14 7.1
02/09/99 Michikamau L 6 6.0 13.5 9.3 94 14 7.1
02/09/99 Michikamau L 7 7.0 13.5 9.3 94 14 7.1
02/09/99 Michikamau L 8 8.0 13.5 9.3 94 14 7.1
02/09/99 Michikamau L 9 9.0 13.4 9.3 93 14 7.0
02/09/99 Michikamau L 10 10.0 13.4 9.3 93 14 7.0
02/09/99 Michikamau L 11 15.0 13.4 9.3 93 14 7.0
02/09/99 Michikamau L 12 20.0 13.4 9.3 93 14 7.0
02/09/99 Michikamau L 13 25.0 12.6 9.4 93 14 7.0
02/09/99 Michikamau L 90 10.0 13.6 9.3 94 5-90
02/09/99 Michikamau L 91 24.0 12.6 9.4 93 14 7.0 7.1
03/09/99 Winokapau L 1 1.0 14.7 9.5 94 18 6.7
03/09/99 Winokapau L 2 2.0 14.7 9.4 93 18 6.7 6.7 6-90 trace metals
03/09/99 Winokapau L 3 3.0 14.7 9.4 93 18 6.7
03/09/99 Winokapau L 4 4.0 14.8 9.3 93 18 6.7
03/09/99 Winokapau L 5 5.0 14.8 9.3 93 18 6.7
03/09/99 Winokapau L 6 6.0 14.8 9.3 93 18 6.7
03/09/99 Winokapau L 7 7.0 14.8 9.3 93 18 6.7
03/09/99 Winokapau L 8 8.0 14.8 9.3 93 18 6.7
03/09/99 Winokapau L 9 9.0 14.8 9.3 93 18 6.7
03/09/99 Winokapau L 10 10.0 14.8 9.3 93 18 6.7 6.7
03/09/99 Winokapau L 11 15.0 14.8 9.3 93 18 6.703/09/99 Winokapau L 12 20.0 14.7 9.2 91 18 6.703/09/99 Winokapau L 13 25.0 14.5 9.1 90 18 6.503/09/99 Winokapau L 14 30.0 11.8 8.9 83 17 6.4
03/09/99 Winokapau L 15 40.0 6.6 10.0 82 15 6.203/09/99 Winokapau L 16 50.0 5.7 10.4 83 15 6.3
03/09/99 Winokapau L 17 60.0 5.3 10.5 83 15 6.103/09/99 Winokapau L 18 70.0 4.9 10.6 83 15 6.103/09/99 Winokapau L 19 80.0 4.7 10.6 83 14 6.0
03/09/99 Winokapau L 20 90.0 4.6 10.7 83 15 6.003/09/99 Winokapau L 21 100.0 4.4 10.6 82 15 6.0
03/09/99 Winokapau L 22 110.0 4.3 10.7 83 15 6.0
6-90 Ri 6-90
03/09/99 Winokapau L 90 10.0 14.8 9.4 93 6-90 6-90 R2, blind
03/09/99 Winokapau L 91 114.0 4.3 10.6 82 15 6.0 6.1
Page 3Date Station Sample Depth Temp. Dissolved 02 Conductivity pH Validat. Replicat. Sample Remarks
(m) (°C) Oxygen Saturat. (pS/cm) pH ID(mgIL) (%) (PSC)
Cl0 dO 010 010 C3003/09/99 Gull L 1 1.0 17.2 9.4 98 17 7.203/09/99 Gull L 2 2.0 17.2 9.3 97 17 7.2 7.2 7-90 trace metals03/09/99 Gull L 3 3.0 17.2 9.3 97 17 7.203/09/99 Gull L 4 4.0 17.0 9.3 97 17 7.203/09/99 Gull L 5 5.0 17.0 9.3 97 17 7.203/09/99 Gull L 6 6.0 17.0 9.3 97 17 7.203/09/99 Gull L 7 7.0 17.0 9.3 97 17 7.203/09/99 Gull L 8 8.0 17.0 9.3 97 17 7.103/09/99 Gull L 9 9.0 17.0 9.3 97 17 7.103/09/99 Gull L 10 10.0 17.0 9.2 96 17 7.103/09/99 Gull L 11 12.0 16.9 9.2 96 17 7.103/09/99 Gull L 90 10.0 17.1 9.3 97 7-9003/09/99 Gull L 91 13.0 16.9 9.2 96 17 7.1 7.2
05/10/99 LJoseph 1 1.0 10.4 9.8 93 15 7.005/10/99 L Joseph 2 2.0 10.4 9.7 92 15 7.0 6.9 1 trace metals05/10/99 LJoseph 3 3.0 10.4 9.7 92 15 7.005/10/99 L Joseph 4 4.0 10.4 9.7 92 15 7.005/10/99 L Joseph 5 5.0 10.4 9.7 92 15 7.005/10/99 L Joseph 6 6.0 10.4 9.7 92 15 7.005/10/99 L Joseph 7 7.0 10.4 9.7 92 15 7.005/10/99 L Joseph 8 8.0 10.4 9.7 92 15 7.005/10/99 LJoseph 9 9.0 10.4 9.7 92 15 7.005/10/99 LJoseph 10 10.0 10.4 9.7 92 15 7.005/10/99 L Joseph 11 15.0 10.4 9.7 92 15 7.005/10/99 L Joseph 12 20.0 10.4 9.7 92 15 7.005/10/99 L Joseph 13 30.0 10.3 9.6 91 15 6.905/10/99 L Joseph 14 40.0 10.4 9.7 92 15 6.905/10/99 L Joseph 15 50.0 10.3 9.7 92 15 6.905/10/99 L Joseph 16 60.0 10.3 9.7 92 15 6.905/10/99 LJoseph 17 62.0 10.2 9.7 91 15 6.905/10/99 L Joseph 90 10.0 10.4 9.7 9205/10/99 L Joseph 91 65.0 10.2 9.7 91 14 6.9 6.9 1-91
05/10/99 Atikonak L 1 1.0 8.5 10.3 93 15 7.105/10/99 Atikonak L 2 2.0 8.4 10.3 93 15 7.0 7.0 2 trace metals05/10/99 Atikonak L 3 3.0 8.4 10.3 93 15 7.105/10/99 Atikonak L 4 4.0 8.3 10.3 93 15 7.005/10/99 Atikonak L 5 5.0 8.3 10.3 93 15 7.005/10/99 Atikoriak L 6 6.0 8.4 10.3 93 15 7.005/10/99 .Atikonak L 7 7.0 8.3 10.3 93 15 7.005/10/99 Atikonak L 8 8.0 8.3 10.3 93 15 7.005/10/99 Atikoriak L 9 9.0 8.3 10.2 92 15 7.005/10/99 Atikoriak L 10 10.0 8.3 10.2 92 15 7.005/10/99 Atikonak L 90 10.0 8.4 10.3 93 205/10/99 Atikonak L 91 10.5 8.3 10.2 92 15 7.0 7.0
05/10/99 Gabbro L 1 1.0 8.0 10.4 92 17 7.205/10/99 Gabbro L 2 2.0 8.0 10.4 92 17 7.2 7.2 3 trace metals05/10/99 Gabbro L 3 3.0 8.0 10.4 92 17 7.205/10/99 Gabbro L 4 4.0 8.0 10.4 92 17 7.205/10/99 Gabbro L 5 5.0 8.0 10.5 93 17 7.205/10/99 Gabbro L 6 6.0 8.0 10.5 93 17 7.205/10/99 Gabbro L 7 7.0 8.0 10.5 93 17 7.205/10/99 Gabbro L 8 8.0 8.0 10.4 92 17 7.205/10/99 Gabbro L 9 9.0 8.0 10.4 92 17 7.205/10/99 Gabbro L 10 10.0 8.0 10.4 92 17 7.205/10/99 Gabbro L 11 12.0 8.0 10.5 93 17 7.205/10/99 Gabbro L 90 10.0 8.0 10.4 92 305/10/99 Gatibro L 91 13.0 8.0 10.5 93 17 7.2 7.2
Page 4
Date Station Sample Depth Temp. Dissolved 02 Conductivity pH Validat. Replicat. Sample Remarks(m) (°C) Oxygen Saturat. (pS/cm) pH ID
(mgIL) (%) (PSC)C10 dO dO do C30
06/10/99 Lobstick L 1 1.0 7.7 10.4 91 18 7.106/10/99 Lobstick L 2 2.0 7.6 10.4 91 18 7.1 7.1 4 trace metals06/10/99 Lobstick L 3 3.0 7.6 10.4 91 18 7.106/10/99 Lobstick L 4 4.0 7.6 10.4 91 18 7.106/10/99 Lobstick L 5 5.0 7.6 10.4 91 18 7.106/10/99 Lobstick L 6 6.0 7.6 10.4 91 18 7.106/10/99 Lobstick L 7 7.0 7.6 10.4 91 18 7.106/10/99 Lobstick L 8 8.0 7.5 10.4 91 18 7.106/10/99 Lobstick L 9 9.0 7.5 10.4 91 18 7.106/10/99 Lobalick L 10 10.0 7.5 10.4 91 18 7.106/10/99 Lobstick L 11 15.0 7.4 10.5 91 18 7.106/10/99 Lobstick L 90 10.0 7.6 10.4 91 4 4 4a, 4b, blind06/10/99 Lobstick L 91 16.5 7.4 10.4 91 18 7.1 7.2
06/10/99 Michikamau L 1 1.0 8.5 10.4 93 15 7.106/10/99 Michikamau L 2 2.0 8.7 10.3 93 15 7.1 7.1 5 trace metals06/10/99 Michikamau L 3 3.0 8.7 10.3 93 15 7.106/10/99 Michikamau L 4 4.0 8.6 10.3 92 15 7.106/10/99 Michikamau L 5 5.0 8.6 10.3 92 15 7.106/10/99 Michikamau L 6 6.0 8.6 10.3 92 15 7.106/10/99 Michikamau L 7 7.0 8.6 10.3 92 15 7.106/10/99 Michikamau L 8 8.0 8.6 10.3 92 15 7.106/10/99 Michikamau L 9 9.0 8.6 10.3 92 15 7.106/10/99 Michikamau L 10 10.0 8.5 10.3 92 15 7.106/10/99 Michikamau L 11 15.0 8.5 10.3 92 15 7.106/10/99 Michikamau L 12 20.0 8.4 10.3 92 14 7.106/10/99 Michikamau L 13 25.0 8.4 10.3 92 14 7.106/10/99 Michikamau L 90 10.0 8.6 10.3 92 506/10/99 Michikamau L 91 26.5 8.4 10.3 92 14 7.1 7.1
08/10/99 Winokapau L 1 1.0 9.7 10.2 90 19 7.008/10/99 Winokapau L 2 2.0 9.7 10.2 90 19 7.0 6.9 6-2 trace metals08/10/99 Winokapau L 2 2.0 9.7 10.2 90 19 7.008/10/99 Winokapau L 4 4.0 9.7 10.3 91 19 7.008/10/99 Winokapau L 5 5.0 9.7 10.3 91 19 7.008/10/99 Winokapau L 6 6.0 9.6 10.2 90 19 7.008/10/99 Winokapau L 7 7.0 9.6 10.2 90 19 7.008/10/99 Winokapau L 8 8.0 9.6 10.2 90 19 7.008/10/99 Winokapau L 9 9.0 9.6 10.2 90 19 7.008/10/99 VVinokapau L 10 10.0 9.3 10.2 90 19 6.9 7.008/10/99 Winokapau L 11 15.0 9.0 10.2 89 19 6.908/10/99 Winokapau L 12 20.0 8.6 10.2 88 19 6.808/10/99 Winokapau L 13 30.0 6.8 10.1 83 16 6.608/10/99 Winokapau L 14 40.0 5.5 10.2 81 15 6.508/10/99 Winokapau L 15 50.0 5.1 10.3 81 15 6.308/10/99 Winokapau L 16 60.0 4.8 10.3 81 15 6.308/10/99 Winokapau L 90 10.0 9.6 10.2 90 6-9008/10/99 Winokapau L 91 66.0 4.8 10.3 81 15 6.3 6.4
08/10/99 Gull L 1 1.0 9.4 10.7 94 18 6.908/10/99 Gull L 2 2.0 9.4 10.7 94 18 7.0 7.0 7-2 trace metals
08/10/99 Gull L 3 3.0 9.4 10.7 94 18 7.008/10/99 Gull L 4 4.0 9.4 10.7 94 18 7.008/10/99 Gull L 5 5.0 9.4 10.7 94 18 7.008/10/99 Gull L 6 6.0 9.4 10.7 94 18 7.008/10/99 Gull L 7 7.0 9.4 10.7 94 18 7.008/10/99 Gull L 8 8.0 9.4 10.7 94 18 7.008/10/99 Gull L 9 9.0 9.4 10.7 94 18 7.008/10/99 Gull L 10 10.0 9.4 10.7 94 18 7.008/10/99 Gull L 90 10.0 9.4 10.7 94 7-9008/10/99 Gull L 91 12.0 9.4 10.7 94 18 7.0 7.0
APPENDIX 2
1999 Water Quality and Chlorophyll StudyField Lab Results
APPENDIX 2 - 1999 Water Quality and Chlorophyll Study - Field Lab Results
Legend
Date: Date of analysis (same as sampling)
Station: Lake sampled
Sample: #2 water samples taken at 2 m from the surface for the determination of trace metalsand Winkler 02 validation
#90 integrated water sample from 0 to 10 m (meter readings averaged)These rather than HYDROLAB data used in results
#91 bottom sample collected at 1 m above the bottom
Lab. Temp: Water temperature recorded during lab analysis
pH: Determined using (C30) Hannah pH meter with temperature and Orion Ross pH probe
Conduct.: Determined by (C35), Radiometer Copenhagen lab conductivity meter
02 Winkler: Determined by (C24) Winkler alkali azide titration. These results were used to correctHYDROLAB results
Alkalinity: (J83) titration with 0.02 N sulphuric acid to pH 4.5 and 4.2 endpoint values
Bicarbonate: (J83) titration with 0.02 N sulphuric acid to pH 4.5 and 4.2 endpoint values
TIC: Total inorganic carbon determined by (J83) titration with 0.02 N sulphuric acid to pH 4.5and 4.2 endpoint values
Chlorophyll Filtration: Indicates whether sample was filtered for chlorophyll analysis
APPENDIX 2: 1999 Water Quality and Chlorophyll Study - Field Lab Results
Date Station Sample Lab Temp.
C30*
pH
C30
Conduct(pSlcm)
C35
02 Winkler(mg/L)024
Alkalinity(mgIL)
J83
Bicarbonate(mgIL)
J83
TIC(mg/L}
J83
ChlorophyllFiltration
01/09/99 LJoseph 90 15.6 6.9 17 4.1 5.0 1.3 Yes01/09/99 L Joseph 91 12.0 6.5 16 4.6 5.7 2 101109/99 Atikonak L 90 13.5 7.0 15 4.4 5.3 1.3 Yes01/09/99 Atikonak L 91 13.9 6.9 15 4.4 5.3 1.402/09/99 Gabbro L 2 9.002/09/99 GabbroL 90 16.6 6.9 16 4.4 5.3 1.4 Yes02/09/99 Gabbro L 91 16.7 6.9 16 9.0 4.9 6.0 1.602/09/99 Lobstick L 2 9.002/09/99 Lobstick L 90 16.8 7.0 20 7.0 8.5 2.1 Yes02/09/99 Lobstick L 91 17.5 6.9 20 8.4 6.4 7.8 2.102/09/99 Michikamau L 90 16.3 6.9 17 5.2 6.3 1.6 Yes02/09/99 Michikamau L 91 16.0 6.8 16 4.9 6.0 1.703/09/99 Winokapau L 90 13.0 7.0 19 6.7 8.2 2.0 Yes03/09/99 Winokapau L 91 11.8 6.4 17 10.5 7.7 9.4 3.903/09/99 Gull L 2 9.003/09/99 Gull L 90 14.8 7.1 20 6.7 8.2 1 9 Yes03/09/99 Gull L 91 15.0 7.1 20 8.9 5.7 6.9 1.605/10/99 L Joseph 2 10.005/10/99 LJoseph 90 18.0 6.8 15 4.4 5.3 1 4 Yes05/10/99 LJoseph 91 18.0 6.7 15 10.0 4.4 5.3 1.605/10/99 Atikonak L 2 10.305/10/99 Atikonak L 90 18.0 6.8 15 4.9 6.0 1 6 Yes05/10/99 Atikonak L 91 18.0 6.7 15 10.4 4.6 5.6 1 705/10/99 Gabbro L 2 10.405/10/99 Gabbro L 90 18.0 6.9 17 6.0 7.3 1.9 Yes05/10/99 Gabbro L 91 18.0 6.9 17 10.4 5.7 7.0 1.806/10/99 Lobstick L 2 10.306/10/99 Lobstick L 90 9.4 6.9 19 6.5 8.0 22 Yes06/10/99 Lobstick L 91 10.9 6.8 19 10.4 6.3 7.6 2206/10/99 Michikamsu L 2 10.106/10/99 Michikamau L 90 11.1 6.7 15 4.9 6.0 1.9 Yes06/10/99 Michikamsu L 91 10.4 6.8 15 10.2 4.6 5.6 1.608/10/99 Winokapau L 2 10.208/10/99 Winokapau L 90 10.0 6.8 20 8.2 10.0 29 Yes08/10/99 Winokapau L 91 8.0 6.4 16 11.5 4.9 6.0 2.608/10/99 Gull L 2 9.608/10/99 Gull L 90 9.7 6.8 19 4.1 5.0 1 4 Yes08/10/99 Gull L 91 10.4 6.8 19 6.3 7.6 2.2
* see Legend for methods
mm 8.0 6.4 15.0 8.4 4.1 5.0 1.3max 18.0 7.1 20.0 11.5 8.2 10.0 3.9
APPENDIX 3
1999 Water Quality and Chlorophyll StudyAnalytical Lab Results - Water
APPENDIX 3 1999 Water Quality and Chlorophyll Study - Analytical Lab Results - Water
Legend
Parameter: Analytical parameter determined by laboratory analysisLOQ: Level of Quantification - minimum result that can be quantified on a repeated basisStation-Sample: Lake sampled - detail of depth of sample provided in brackets
APPENDIX 3: 1999 Water Quality and Chlorophyll Study - Analytical Lab Results - Water
Sampled 1-3 September 1999
2 a)w
a)-
.C4 Ca_j Ca
a) a)E
-E 2 E
)
oE •
- eQ
Parameter LOQ
PheopigmentsDOCTOOTDS (180 Deg)TSSTrue ColourTurbiditySuiphidesAmmoniaReactive PhosphorousOrtho-PhosphatesReactive SilicaTotal PhosporousTanninsTKNChlorideNitrates & NitritesSulphateSeleniumCalciumMagnesiumSodiumPotassiumIronAluminumAntimonyArsenicBariumBerylliumBismuthBoronCadmiumChromiumCobaltCopperLeadManganeseMolybdenumNickelSilverStrontiumThalliumTinTitaniumUraniumVanadiumZinc
0.10.10.50.5200.5
0.20.0
0.020.0020.0020.050.002
0.10.030.2
0.020.5
0.00010.1
0.010.020.020.020.0100.0020.0020.0050.0050.0020.005
0.00010.0020.0010.0020.00050.0020.0020.002
0.00010.005
0.00010.0020.002
0.00010.0020.002
llg/Lpg/Lmg/Lmg/Lmg/Lmg/LUCVUTNmg/L
mg N/Lmg P/Lmg P/L
mg SiO2/Lmg P/Lmg/L
mg N/Lmg Cl/Lmg N/L
mg SO4/Lmg/Lmg/LmgtLmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/LmgfLmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/Lmg/L
1.00.73.67.4<200.7280.5
0.030.003
<0.0022.50
<0.0020.8
0.15<0.2<0.150.8
<0.00011.4
0.410.380.240.080.030<0.002<0.0020.005<0.005<0.002<0.005
<0.0001<0.002<0.001<0.002<0.00050.006<0.002<0.002
<0.00010.012
<0.0001<0.002<0.002
<0 .000 1<0.0020.003
4.5
<0.020.030.005
<0.002
0.006
0.16<0.2
<0.150.7
<0.00011.4
0.410.380.230.100.060
<0.002<0.0020.060
<0.005<0.002<0.0050.0360<0.002<0.00 1<0.002<0.0005
0.026<0.002<0.002
<0.00010.014
<0.0001<0.002<0.002
<0 .000 1<0.0020.007
2.10.23.43.7331.3280.7
0.020.004<0.002
2.800.006
0.70.15<0.2<0.15
0.7<0.0001
1.40.340.440.250.140.030<0.002<0.002<0.005<0.005<0.002<0.005<0.0001<0.002<0.001<0.002<0.00050.009<0.002<0.002
<0.00010.011
<0.0001<0.002<0.002<0 .0001<0.0020.004
2.30.43.23.6311.1250.8
<0.020.020.004
<0.0022.370.005
0.70.13<0.2<0.15
0.70.0001
1.60.440.410.230.060.030<0.002<0.0020.007
<0.005<0.002<0.005
<0 .000 1<0.002<0.001<0.002<0.00050.009<0.002<0.002
<0.00010.011
<0.0001<0.002<0.002<0.0001<0.0020.003
3.60.63.43.4<201.5201.0
<0.020.040.0080.0041.01
0.0070.5
0.130.2
<0.151.0
<0.00013.4
0.710.420.270.110.520<0.002<0.0020.019<0.005<0.002<0.005
<0 .000 1<0.002<0.0010.0040.00070.110
<0.002<0.002
<0.00010.034
<0.0001<0.0020.007
<0.0001<0.0020.017
a)- a,(a -
(a
E E:EQ OQQ .E 'E'
e. e. o2.2 1.7 1.2
<0.1 0.4 0.22.2 3.4 3.52.4 4.1 3.920 <20 320.6 0.9 0.712 28 280.8 1.0 0.7
0.03 0.02 0.020.003 0.005 0.0040.002 <0.002 <0.0020.67 2.19 2.270.007 0.008 0.005
0.3 0.7 0.80.11 0.12 <0.030.2 0.2 0.3
<0.15 <0.15 <0.150.7 1.0 0.9
0.0001 <0.0001 <0.00011.4 2.0 1.8
0.42 0.63 0.580.35 0.41 0.420.21 0.25 0.250.04 0.11 0.06
0.020 0.030 0.040<0.002 <0.002 <0.002<0.002 <0.002 <0.002<0.005 0.008 0.007<0.005 <0.005 <0.005<0.002 <0.002 <0.002<0.005 <0.005 <0.005
<0.0001 <0.0001 <0.0001<0.002 <0.002 <0.002<0.001 <0.001 <0.001<0.002 <0.002 <0.002<0.0005 <0.0005 <0.0005
0.006 0.020 0.010<0.002 <0.002 <0.002<0.002 <0.002 <0.002
<0.0001 <0.0001 <0.00010.008 0.012 0.011
<0.0001 <0.0001 <0.0001<0.002 <0.002 <0.002<0.002 <0.002 <0.002<0.0001 <0.0001 <0.0001<0.002 <0.002 <0.0020.003 0.004 0.003
Sampled 5-8 October 1999
arameter
wEo
•
1
..0
w E2
o E•
E0
. -
.
2E.0.0
(_
E. ,-
.3.
.
E.E
ou -•
a
0. 0.
0c E
.
0. ......
.E0c -
e.
. 0.
-- E
.
-
th.Chlorophyll a 1.3 1.7 1.7 3.3 1.3 1.2 0.8Pheopigments 0.4 0.5 0.6 1.0 0.4 0.6 0.4DOC 3.4 4.2 3.5 3.0 2.8 1.6 3.1 3.5TOC 3.7 4.4 3.8 3.0 3.4 1.8 3.5 3.8TDS (180 Deg) 25 23 <20 22 <20 21 21TSS 0.8 0.9 1.0 1.9 0.6 0.9 1.1True Colour 27 30 23 23 7 24 30Turbidity 0.2 0.2 <0.2 0.5 <0.2 0.5 0.5SulphidesAmmonia 0.02 0.02 0.02 0.02 0.02 0.02 0.03 0.03Reactive Phosphorous 0.003 0.004 0.002 0.003 0.006 0.003 0.004 0.004Ortho-Phosphates <0.002 0.002 <0.002 0.002 0.004 ^0.002 0.002 0.002Reactive Silica 2.52 3.03 2.10 0.52 0.45 2.14 2.68Total Phosporous 0.003 0.004 0.005 0.002 0.008 0.002 0.004 0.004Tannins 0.8 0.9 0.7 0.6 0.3 0.7 0.8TKN 0.14 0.16 0.14 0.11 0.18 0.12 0.14 0.13Chloride 0.2 <0.2 <0.2 <0.2 0.2 <0.2 0.5 0.4Nitrates & Nitrites <0.02 <0.02 <0.02 <0.02 <0.02 0.03 <0.02 0.04Sulphate 1.1 0.8 0.8 0.8 1.0 1.0 1.3 1.1Selenium 0.0001 0.0001 0.0001 0.0002 0.0001 0.0002 0.0001 0.0001Calcium 1.7 2.0 1.7 2.1 2.8 1.5 2.4 2.2Magnesium 0.39 0.36 0.34 0.48 0.60 0.36 0.59 0.55Sodium 0.38 0.35 0.44 0.36 0.35 0.32 0.37 0.38Potassium 0.19 0.19 0.22 0.18 0.19 0.16 0.19 0.18Iron 0.09 0.08 0.16 0.05 0.14 0.02 0.08 0.09Aluminum 0.030 0.030 0.040 <0.030 0.030 0.030 0.110Antimony <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Arsenic <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Barium 0.005 0.005 <0.005 0.009 0.006 <0.005 0.006 0.008Beryllium <0.005 <0.005 <0.005 <0.005 <0.005 <0.005 <0.005 <0.005Bismuth <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Boron <0.005 <0.005 <0.005 <0.005 <0.005 <0.005 <0.005 <0.005Cadmium <0.0001 <0.0001 <0.0001 0.0001 <0.0001 <0.0001 <0.0001 <0.0001Chromium <0.002 <0.002 0.003 <0.002 <0.002 <0.002 <0.002 <0.002Cobalt <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001Copper <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Lead <0.0005 0.0005 <0.0005 <0.0005 <0.0005 <0.0005 <0.0005 <0.0005Manganese 0.010 0.011 0.012 0.009 0.028 0.009 0.010 0.021Molybdenum <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Nickel <0.002 <0.002 0.022 <0.002 <0.002 <0.002 <0.002 <0.002Silver <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001Strontium 0.013 0.013 0.012 0.011 0.008 0.009 0.010 0.014Thallium <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001Tin <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Titanium <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Uranium <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001Vanadium <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002Zinc <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002
AnalyticalAnalysis Method Description
(Code)_____________________________________________________________________________________________
Ammonia J19 Ammonia-Selective Electrode Method - APHA, AWWA, WPCF, 1992. StandardMethods for the Examination of Water and Wastewater, 18th edition, 4500-NH3 F.
TKN Ji 3 Acid digestion, distillation, and analysis with an ammonia-selective electrode -APHA, AWWA, WPCF, 1992. Standard Methods for theExamination of Water and
Wastewater, 18th edition, 4500-N org.B.
Dissolved Organic R05 Filtration through a 0.45-urn-pore-diameter filter (in the laboratory) - Persulfate -
Carbon Ultraviolet Hydrolysis and Automated Phenolphthalein Colourimetric Method -
USEPA 415.1
Total Organic Carbon R03 Persulfate - Ultraviolet Hydrolysis and Automated Phenolphthalein Colourimetric
Method - USEPA 415.1
Chlorophyll a & 191 Acetone Extraction and Fluorometric Determination - APHA, AWWA, WPCF, 1992.
Pheopigments Standard Methods for the Examination of Water and Wastewater, 18th edition,
1 0200H.3.Ion Chromatography - APHA, AWWA, WPCF, 1992. Standard Methods for the
Examination of Water and Wastewater, 18th edition, 5550B.
True Colour H08 Centrifugation and Visual Comparison with Platinum-Cobalt Standards - APHA,AWWA, WPCF, 1992. Standard Methods for the Examination of Water and
Wastewater, 18th edition, 2120 B.
H43 Filtration of a 1-litre sample through a glass-fibre filter and Gravimetric Analysis(105°C) - APHA, AWWA, WPCF, 1992. Standard Methods for the Examination of
Water and Wastewater, 18th edition, 2540D.
Metals K02 Metals by Plasma Emission Spectroscopy - APHA, AWWA, WPCF, 1992. StandardMethods for the Examination of Water and Wastewater, 18th edition, 3120 B.
Phosphorous J45 Dosage colorimétrique avec molybdate/antimoine et acide ascorbique base sur lesspecifications de Ia méthode semiautomatique de dosage a teclmicon.
_____________
Minéralisation avec les acides H2SO4 - HNO3 et dosage colorimétrique avecmolybdate/antimoine et acide ascorbique base sur les specifications de la méthodesemiautomatique de dosage a techriicon.
Digestion au persulfate a lautoclave (méthode SEBJ, code J41) et dosagecolorimétrique avec molybdate/antimoine et acide ascorbique base sur lesspecifications de la méthode semiautomatique de dosage a technicon.
____________________ _____________
Determination du sélénium par génération d'hydrures/spectrophotomètre démission
atomique au plasma d'argon. APHA, AWWA, WPCF, 1992. Standard Methods forthe Examination of Water and Wastewater, 18th edition, 3500-Se B et C.
Reactive Silica 185 Dosage colorimétrique avec molybdate d'ammonium et acide oxalique base sur lesspecifications de la méthode semiautomatique de dosage a technicon.
Determination des anions par chromatographie ionique methods for the Examinationof Water and Wastewater, 18th edition, 5550B.
Tam-iins J9 1 Dosage colorimétrique avec les acides phosphotungstique et phosphomolybdique -APHA, AWWA, WPCF, 1992. Standard Methods for the Examination of Water and
Wastewater, 18th edition, 411 OB.
Turbidity Hi 1 Dosage néphélométrique - APHA, AWWA, WPCF, 1992. Standard Methods for theExamination of Water and Wastewater, 18th edition, 2130B.
APPENDIX 4
1999 Water Quality and Chlorophyll StudyChlorophyll Analysis Results
APPENDIX 4 1999 Water Quality and Chlorophyll Study - Chlorophyll Analysis Results
Legend
Site: Lake sampled
Replicate: Samples are labelled la-lb and 2a, 2b, 3a, to indicate replicates taken
Mean: Mean concentration of samples for single site
Std. Dev.: Standard deviation
C.V.: Coefficient of variance (%)
AP
PE
ND
IX 4
: 19
99 W
ater
Qua
lity
and
Chl
orop
hyll
Stud
y-
Chl
orop
hyll
Ana
lysi
s R
esul
ts
Trip
I- 1
-3 S
epte
mbe
r 199
9Tr
ip 2
- 5-8
Oct
ober
199
9
Chl
orop
hyll
Con
cent
ratio
n (m
g/m
a)C
hlor
ophy
ll C
once
ntra
tion
(mg/
ms)
SITE
Ialb
2a2b
3aM
ean
Std.
Dev
.C
V. (%
)1a
lb2a
2bM
ean
Std.
Dev
.C
.V. (
%)
Jose
ph1.
321.
271.
441.
531.
390.
128.
451.
481.
361.
341.
390.
085.
43
Atik
onak
2.24
2.20
2.16
1.91
1.82
2.07
0.19
9.12
1.71
1.54
171
1.65
0.10
5.94
Gab
bro
2.13
2.13
2.06
2.08
2.10
0.04
1.69
240
2.10
2.81
2.44
0.36
14.6
3
Lobs
tick
3.78
3.46
3.90
3.64
3.70
0.19
5.12
3.89
3.50
3.46
3.59
3.61
0.19
5.39
Mic
hika
mau
1.64
1.61
1.54
1.46
1.56
0.08
5.13
1.52
1.48
1.74
1.73
1.62
0.14
8.45
Win
okap
au1.
541.
661.
781.
781.
690.
116.
801.
231.
371.
481.
521.
400.
139.
28
Gul
l1.
000.
990.
950.
980.
980.
022.
200.
850.
921.
000.
870.
910.
077.
34
Not
e:Th
e sh
aded
val
ues
wer
e tra
nspo
sed
in e
rror
dur
ing
data
tran
scrip
tion.
The
se h
ave
been
cor
rect
ed to
con
form
with
logi
cal p
atte
rn o
f res
ults
.
APPENDIX 5
1999 Water Quality and Chlorophyll StudyZooplankton Analysis Results
APPENDIX 5 1999 Water Quality and Chlorophyll Study - Zooplankton Analysis Results
Legend
Site: Lake sampled
Replicate: Two analyses were conducted for each site
(Category): Taxa categorized as Copepods, Cladocerans, or Rotifers
Total: Total biomass of all categories
Std. Dev.: Standard deviation
Coefficient of variance (%)
APPENDIX 5: 1999 Water Quality and Chlorophyll Study - Zooplankton Analysis Results
ZOOPLANKTON BIOMASS DATA (mg/rn3)
SITE REPLICATE COPEPODS CLADOCERANS ROTIFERS TOTAL STD. DEV.(a)
C.V. (%)(b)
TRIP 1 (1-3 September 1999)
Lac Joseph 1 69.22 53.48 2.39 125.092 42.44 37.86 5.82 86.12
mean 55.83 45.67 4.11 105.61 27.56 26.09
Atikonak 1 20.47 79.58 1.11 101.162 34.44 162.39 3.55 200.38
mean 27.46 120.99 2.33 150.77 70.16 46.53
Gabbro 1 108.43 103.21 6.18 217.822 110.45 58.82 8.18 177.45
mean 109.44 81.02 7.18 197.64 28.55 14.44
Lobstick 1 198.65 234.84 1.69 435.182 170.47 267.08 6.24 443.79
mean 184.56 250.96 3.97 439.49 6.09 1.39
Michikamau 1 132.81 51.38 10.16 194.352 165.73 124.43 21.29 311.45
mean 149.27 87.91 15.73 252.90 82.80 32.74
Winokapau 1 7.65 3.10 0.89 11.642 4.56 4.54 0.50 9.60
mean 6.11 3.82 0.70 10.62 1.44 13.58
Gull 1 0.66 1.02 0.20 1.882 0.08 0.02 0.14 0.24
mean 0.37 0.52 0.17 1.06 1.16 109.40
Mean C.V. (%) 34.9
a. Standard Deviation estimated using N-i weightingb. Coefficient of Variability calculated as: (Std. Dev./mean)x 100
APPENDIX 6
1999 Water Quality and Chlorophyll StudyMercury in Water and Zooplankton
UMVERSITE DU QUEBEC A MONTRÉAL
CFJAIRE DE RECRERCHE EN ENVIRONNEMENTHYDRO-QUEBEC/CRSNG/UQAM
pp
p
p Contrat de services professionels
p
p.
p
Suivi environnemental, projet Churchill, 1999p
p
pI
ANALYSES DE MERCURE TOTAL ET DE METHYLMERCURE SURDES ECHANTILLONS D1EAU ET DE ZOOPLANCTON
Isabelle Rheault, biochimiste
janvier 2000
)
HYDRO-QUEBEC/CRSNG/UQAM
Contrat de services professionels
Suivi environnemental, projet Churchill, 1999
ANALYSES DE MERCURE TOTAL ET DE METHYLMERCURE SURDES ECHANTILLONS D1EAU ET DE ZOOPLANCTON
Isabelle Rheault, biochirniste
janvier 2000
TABLE DES MATLERES
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pageTABLE DES MATIERES
LISTE DES TABLEAUX 1
1.0 INTRODUCTION 1
2.0 MATERIEL ET M]THODES POUR LES ANALYSES DE ZOOPLANCTON
2.1 Preparation des échantillons 22.2 Analyse du mercure total 22.3 Analyse du méthylmercure 3
3.0 RESULTATS DANS LE PLANCTON 6
4.0 MATERIEL ET METHODES POUR LES ANALYSES DEAU
4. 1 Analyse du mercure total 7
4.2 Analyse du méthylmercure 9
5.0 RESULTATS DANS UEAU 11
6.0 COHERENCE DES RESULTATS
6. 1 Zooplancton 13
136.2 Eau
LISTE DES TABLEAUX
...................................................................................
................................
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.................................................................................
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page
TABLEAU 1 Vai-iabililé des blancs danalyse pour les mesures de
mercure total et de méthylmercure dans Ic
zooplancton 4
TABLEAU 2 Valeurs certifiées et mesurées en mercure total et
en méthylmercure de létalon TORT-2
TABLEAU 3 Teneurs en mercure total et en méthylmercure
dans le zooplancton 6
TABLEAU 4 Teneurs en mercure dans Ia solution de persulfate
de potassium 8
TABLEAU 5 Variabilité des blancs danalyse pour les mesures
de méthylmercure dans leau 10
TABLEAU 6 Teneurs en mercure total dans leau 11
12TABLEAU 7 Teneurs en méthylmercure dans leau
I
1.0 INTRODUCTION
Dans Ic cadre dun suivi envronnemental, Ic groupe Conseil Génivar a
prélevé des échantillons d'eau filtrée et non filtrée ainsi que d u
zooplancton dans Ia region Churchill. Le laboratoire de Ia Chaire de
recherche en environnement Hydro-Québec/CRSNG/UQAM a reçu le
mandat d'analyser Ic contenu en mercure total et en méthylmercure
de ces échantillons.
En plus de presenter les résultats de ces analyses, ce rapport décrit
brièvement les principales étapes analytiques et les contrOles effectués
pour assurer Ia qualité des résultats.
2
2.0 MATERIEL ET METHODES POUR LES ANALYSES DEZOOPLANCTON
2.1 Prépa ration des écliantil[ons
A Ia reception des échantillons au laboratoire de FUQAM, les pots ont
été identifies de 1 a 5 pour chacune des stations. Puis les échantiljons
out été lyophylisés pour une période de 4 jours. us ont été broyés et
homogénéisés a laide d'une tige de verre dans Ia fiole contnant
léchantillon. Ce protocole réduit les risques de contamination ainsi que
les pertes déchantillon lors des manipulations.
2.2 Analyse du rnercure total
Une partie de léchantillon est utilisée pour Ia digestion. Le poids sec
prélevé peut varier entre 3 et 15 mg, selon la quantite d'échantillon
disponible. Trois a cinq pots par station sont utilisés pour les analyses
sauf dans le cas de Ia station 7, o les pots 2 et 3 ont été regroupés.
La digestion se fait en ajoutant 1 mE de HNO3 (12N) et 0.1 mL de HCI
(6N) a léchantillon puis en chauffant a 120°C pendant 4 heures. Un
système de ventilation refroidi la partie supérieure du tube pour
éviter les pertes de mercure par evaporation. Le digestat est ramené a
un volume final de 3 mL avec de leau NANOpure®, puis analyse par
mesure de la fluorescence atomique du mercure libéré lorsque réduit
par Sn (II).
Dans le cas oi Ia quantité déchantillon disponible se situe aux
alentours de 1 mg, le protocole de digestion doit ëtre adapté. Lesquantités dacides sont plutôt de lordre de 40 p.L de HNO3 (12N) et de
5 tL de HCI (6N). La digestion se fait dans des tubes avec bouchons
dans une étuve a 120°C. Le volume final est ramené a 0.545 rut avec
de Ieau NANOpure®.
3
I
I
I
I
I
I
I
I
Une série de digestions comprend deux blancs de digestion et deux
étalons certifies, TORT-2.
Lappareil est calibre par injection de quantilés connues de Hg(ll)
(400-1000 pg Hg). La limite de detection est de 2.4 pg de mercure, cc
qui correspond a 0.48 ng.Hg.g (poids sec) pour un échantillon type
de .5 mg. Cette valeur correspond a trois fois Ia variabilité des blancs
(3o tableau 1).
La precision et Ia reproductibilité de Ia méthode sont évaluées par
lanalyse dun étalon certifié, le TORT-2, un échantillon pancréo-
hépatique de homard. Une valeur moyenne de rnercure total de
266 ± 14 ng.Hg.g1 (poids sec) a été obtenue alors que Ia valeur
certifiée est de 270 ±60 ng.Hg.g (poids sec) (tableau 2). Les valeurs
mesurées de létalon certifié se situent dans un écart acceptable de Ia
valeur certifiée.
2.3 Analyse du méthylmercure
Uric partie de léchantillon est utilisée pour lextraction du methyl
mercure. Le poids sec prélevé peut varier entre 0.5 mg et 5 mg,
dépendant de la quantité déchantillon disponible. Lextraction d u
méthylmercure se fait en ajoutant 500 jiL dune solution de KOH/MeOH
(1 g/4 mL) a léchantillon puis en chauffant a une temperature de 68°C
durant 8 heures avec agitation a mi-temps et a Ia fin.
Léthylation du méthylmercure se fait en ajoutant 50 iL d'échantilllon,
55 tL dacide lactique (4M) et 200 p.L de tétraéthylborate de sodium
(1%) a uric trentaine de mL deau NAMOpure®. Dans ces conditions, u n
pH optimal de 4.5 nécessaire pour léthylation est obtenu. Le methyl
mercure éthylé est extrait de Ia solution et adsorbé sur uric colonne de
Tenax par une agitation de 5 minutes et un barbotage de 10 minutes
avec de lair comprimé.
4
b
La colonne de Tenax est séchée par un flot dair pendant 10 minutes
pour être ensuite fixée au chromatographe en phase gazeuse (flux
d'argon de 15 mL/min, temperature de la colonne a 75°C), pujs
chauffée 1 minute, de façon a libérer les espèces adsorbées. Api-es 6
minutes de retention sur Ia colonne chromatographique, le
méthylmercure est quantifié par mesure de Ia fluorescence atomique.
Une série dextraction comprend toujours un blanc et un étalon
certifié, le TORT-2. lJappareil est calibre par éthylation de quantites
connues de MeHgCI, dont Ia concentration a été vdrifiée par lanalyse
du mercure total. La limite de detection est de 1.0 pg de
méthylmercure, cc qui correspond a 0.5 ng.g' (poids sec) pour u n
échantillon de 2 mg. Cette valeur correspond a trois fois la variabilité
des blancs (3G, tableau 1). La limite de detection de la méthode,
exprimée en mercure, est donc évaluée a 0.4 ng.Hg.g (poids sec) pour
un échantillon de 2 mg.
TABLEAU 1
Variabilité des blancs dtanalyse pour les
total et de méthylmercure dans
Mercure total(pg)
1.22.82.1
Mo ye nn eEcart-Type (c)Limite de detection (3G)
inesures dernercure
Ic zooplancton
Met h yl me r Cu r(pg)
2.62.12.8
2.0 2.50.8 0.32.4 LO
5
) La precision et Ia reproductibilité de Ia méthode sont évaluées par
lanalyse dun é talon certifié, soit le TORT-2. Une valeur moyenne d e
) méthylmercure de 164 ± 4 ngHg.g1 (poids sec) a été obtenue a lors
que La valeur certifiée est de 152 ± 13 ng.Hg.g (poids sec)
(tableau 2). La valeur rnesurée de ltétalon certifié se situe dans u n
écart acceptable de la valeur certifiée.
TABLEAU 2
Valeurs certifiées et mesurécs des teneurs en mercure total
et en rnéthylmercure de ltétalon TORT-2
Mercure total Méthylmercure
ng.Hg.g (poids sec) ng.g1 (poids sec)exprimé en Hg
Valeurs certifiéesEcart type
Valeurs mesurées
27060
248262283278259
15213
168160165
Moyenne 266 164Ecart type 1 4 4Nombre darialyses 5 3
6
3.0 RESULTATS DANS LE ZOOPLANCTON
TABLEAU 3
Teneurs en mercure total et en rnéthylmercure datis Ic
zoo p Ia a ct o a
p
'Ji
Numéro Hg tota' MeHgéchanttllon ng.Hg.g (poids sec) en equivalent Hg, ng.g1(poids sec)
lère digestion 2e digestion lère digestion 2e digestion
1-1 195 6g
1-2 181 185 59 77
1-3 462 523 67
1-4 248 246 77
1-5 212 ________________________2-1 130 43 40
2-2 118 4g
2-3 122 49
2-4 53
3-1 86 35
3-2 80 21 29
3-3 84 40 46
3-4 41
3-5 29
4-1 67 24 31
4-2 77*77 28
4-3 61 31
4-4 67 37
5-1 127 52
5-2 114 54
5-3 131 51
5-4 121 ______________________________6-1 205 *184 72
6-2 138 *119 72
6-3 219 *221 71
6-4 211
6-5 248 196 ____________________________7-1 *253 574 *247 075 *217
7-2 et 7-3 *166 *100 1- ____
Notc: La digestion des échantillons précédés dun astérisque a été faite avec Ic
protocole adapté (40 jiL de HNO3 12N et de 5 tiL de HCI 6N).
7
4.0 MATERIEL ET METHODES POUR LES ANALYSESDEAU
4.1 Analyse du mci-cure total
Le contenu de Ia bouteille a été degele au refrigérateur puis brassé
avant les analyses. Ensuite, trois parties aliquotes de 10 mL ont été
prélevées par transvasement et mises dans trois tubes de quartz.
L'oxydation du mercure total se fait en ajoutant 100 iL dune soIutioj
de persulfate de potassium 5% a chaque partie aliquote et e n
l'exposant pendant 20 minutes a une source de lumière a
rayonnements ultra-violets. Le mercure contenu dans 5 ml. est alors
analyse par mesure de Ia fluorescence atomique lorsque réduit par
Sn (11).
Les trois résultats sont compares et lorsque La difference est
supérieure a 10%, lautre portion de 5 mL restant dans le tube est
injectée. LTappareil est calibre par injection de quantités connues de
Hg(II) (50-400 pg de Hg).
Dans La solution de persulfate de potassium utilisée pour Ia digestion
du mercure, il y a toujours une trace de mercure. Cette contamination
est mesurée a chaque journée d'analyse et est déjà soustraite de La
concentration totale mesurée sur un échantillon (données présentées
dans le tableau 6). La valeur provenant du persulfate peut varier de
0.06 a 0.13 ng.Hg.L1 selon le lot préparé (tableau 4).
w
*
jr
p
p
p
p
p
p
p
p
p
p
p.
p
p
p
p
TABLEAU 4
Teneui-s cii mercurc dans La solution (IC persulfate de
0 t a s si u rn
Date Concentration dedanaIyse iuercure
dans Ia solution depersulfate 5%
(ng. Hg.L 1)
Concentration deni C r C u r C
qui a été Soustraitedes échantillons
a ii a 1 y Se S
(ng.Hg.L1).(rapport de dilution 1/100)
24/1 1/99 7 0.0725/11/99 7 0.0729/11/99 6 0.0601/12/99 9 0.0907/01/00 13 0.13
Corrime la rnesure du mercure total s'effectue en flot continue, La
variation des mesures de blanc ne peut être utilisde pour évaluer La
limite de detection. Celle-ci est plutôt calculée a partir de la moyenne
de lécart-type des échantillons dans cette série analytique. Un écart-
type moyen (cr) de 0.07 ng.Hg.L' et une limite de detection (3o de
0.21 ng.Hg.L1 sont obtenus pour un échantillon type de 5 mE
(tableau 6)
8
9
4.2 Analyse du rnéthylniercure
a
ppp3
3
3
3
3
pp
p
3
p
p
)
p
p
p
p
p
p
p
Après avoir bien agité Ta bouteille décliantillon, 2 parties aliquotes de
27 a 29 mL sont pesées dans des tubes de Teflon® auxquelles Sont
ajoutés 500 tL de KBr 4M, 500 tiL de H2S04 2M et 200 ftL dAPDC
(1%). La distillation se fait en chauffant les tubes a 110°C pendant 4 a
5 heures en presence dazote. Le distillat est recueilli dans un tube de
verre contenant déjà 10 mL d'eau NANOpure®. Lorsque Ia distillatioii
est terminée, le distillat est transvasé complètement dans une fiole a
éthylation. Le p1-I est ajusté a 4.5 avec 45 tL dacide lactique 4M e
50 jtL de KOH/MeOH (1g14 mL). Puis le méthylmercure est éthylé en
presence de 200 p.L de tetraéthylborate de sodium (1%).
Le méthylmercure éthylé est extrait de Ia solution et adsorbé sur une
colonne de Tenax par une agitation de 5 minutes et un barbotage d e
10 minutes avec de lair comprimé. La colonne de Tenax est séchée par
un flot dair pendant 10 minutes pour être ensuite fixée au
chromatographe en phase gazeuse (flux dargon de 15 mL!min,
temperature de la colonne a 75 °C ), puis chauffée 1 minute de façon a
extraire les espèces adsorbées. Après 6 minutes de retention sur Ia
colonne chromatographique, le méthylmercure est quantifié par
mesure de La fluorescence atomique.
L'appareil est calibre par ethylation de quantités connues détalons de
MeHgCI, dont Ia concentration a été vérifiée par lanalyse du mercure
total. La limite de detection est de 1.45 pg de méthylmercure, ce qui
correspond a 0.052 ng.L1 pour un échantillon de 28 niL. Cette valeur
correspond a trois fois la variabilité des blancs (3, tableau 5). La
limite exprimée en mercure est donc de 0.041 ng.Hg.L' pour u n
échantillon de 28 mL.
I-)10
04
IIIIIIeII
IIIIe9IIIIIIIIIIppIp
p
p)I)0
TABLEAU 5
Variabilité des blaiics d'aualyse pour les mesures de
rnétliylrnercure dans 1eau
Méthylmercurepg
3.52.52.52.92.92.43.12.43.72.82.53.53.43.6
Moyenne
Ecart type (o•)
Umite de detection (3)
3.00.482
1 .45
5.0 RESULTATS DANS L1EAU
e
S __
SS
station
filtrée
re34
67
fantöme
TABLEAU 6
Teneurs en inercure total dans reau
Hg total (ng.Hg.L)lère mesure 2e mesure 3e mesure moyenne écart type
1.27 1.19 1.18 1.21 0.05
1.21 1.12 1.21 1.18 0.14
0.99 1.10 1.10 1.06 0.06
0.73 0.81 0.82 0.79 0.05
0.30 0.28 0.36 0.32 0.04
1.01 0.94 1.00 0.98 0.04
1.26 1.29 1.14 1.23 0.08
1.05 1.14 1.24 1.14 0.10
station Hg total (ng.Hg.L)non filtrée lère mesure 2e mesure 3e mesure moyenne écart type
1 1.27 1.16 1.23 1.22 0.06
2 1.16 1.08 1.06 1.10 0.05
3 0.98 0.84 0.90 .0.91 0.07
4 0.78 0.73 0.73 0.75 0.03
5 0.48 0.40 0.44 0.44 0.04
6 1.06 1.11 0.92 1 .03 0.10
7 1.15 0.98 1.08 1 .07 0.09
fantOme 1.14 0.96 0.95 1.02 0.11
Ecart type moyen 0.07
Limite de detection (3G) 0.21
11
12
TABLEAU 7
Teneurs de rnétliylrnercure dans Peati
Station méthylmercure
(ng.HgL1)
Filtrée1 sous Ia limite de detection2 sous Ia limite de detection3 sous Ia limite de detection4 sous Ia limite de detection5 sous Ia limite de detection6 sous Ia limite de detection7 sous Ia limite de detectionfantOme sous Ia limite de detection
Non filtréee1 sous Ia I imite de detection2 sous Ia limite de detection3 sous Ia limite de detection4 sous Ia limite de detection5 sous Ia Iimite de detection6 sous Ia limite de detection7 sous Ia limite de detectionfantöme sous Ia limite de detection
Note: La limite de detection est de 0.041 ng.Hg.L'
13
6.0 COHERENCE DES RESULTATS
6.1 Zooplaucton
Les problèmes de reproductibilité des résultats observes i certaines
stations dun contenant a rautre, peuvent étre attribués sojt a la
technique déchantillonnage ou a Fhomogéneisation des échantillons.
Les méthodes utilisées pour mesurer le mercure total et le
méthylmercure permettent dtre reproductibles pour un mêrne
échantillon. Ceci est démontré par les résultats obtenus par l'étalon
certifié, TORT-2, qui sont reproductibles. Certains problèmes peuvent
survenir lorsqu'une très faible quantité de materiel est disponible.
Uhomogéneisation de léchantillon est alors plus difficile. Une
combinaison de plus dun contenant dune méme station pour
augmenter Ia quantité déchantillon disponible serait possible, mais est
toujours risquée car si un des contenants est contaminé, ii y a risque
de contaminer le lot au complet. Voici quelques observations faites lors
de lexamen visuel des échantillons:
1) Léchantillon 4-2 contenait une roche non dissoluble par lacide.
2) Pour la station 6, une quantité variable de roche et de sable
pouvait ëtre observée dans chacun des pots échantillonnés.
3) Dans les échantillons 7-2 et 7-3, des résidus rouges et verts ont
été observes (morceaux de peinture?) ainsi quun morceau de
rubant collant. -
Après Ia digestion des échantillons de Ia station 1, seul léchantillon
1-3 contenait des particules noires dans le digestat. Dans Ic cas de Ia
station 7, les résultats de méthylmercure sont anormalement bas pour
du zooplancton.
6.2 Eau
11 ny a pas de difference significative entre les échantillons deau
filtrés et non filtrés pour les analyses de mercure total. 11 est a noter
quil y avait lies peu de particules dans les échantillons non filtrés.