Birch Brook Nordic Ski Club, Labrador: Physical and chemical characteristics of its chalet s drinking water from a private well

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1 Birch Brook Nordic Ski Club, Labrador: Physical and chemical characteristics of its chalet s drinking water from a private well Prepared by: Dr. Merline Fonkwe, P.Geo., Research Scientist Program Manager Mineral Deposits and Environmental Geochemistry Labrador Institute of Memorial University of Newfoundland 219 Hamilton River Road, P.O. Box 490, Station B, Happy Valley-Goose Bay, NL, A0P 1E0, Canada Submitted to the board of directors Birch Brook Nordic Ski Club North West River Road, P.O. Box 386 Station C, Happy Valley-Goose Bay, NL, A0P 1C0, Canada September 28, 2016

2 Disclaimer: The information in this report is provided for informational purposes only. Although, I provide interpretation of the quality of drinking water based on the data we have collected during the sampling period, this subject involves complex hydrochemical and physical processes, and a detailed discussion is not attempted here. Therefore, readers should not rely solely upon the results herein for either general or specific purposes. To cite this report: Fonkwe M.L.D. (2016): Birch Brook Nordic Ski Club, Labrador: Physical and chemical characteristics of its chalet s drinking water from a private well. Birch Brook Nordic Ski Club, Happy Valley-Goose Bay, NL, Canada, vi + 18 pp. Address correspondence to: Dr. Merline Fonkwe Labrador Institute of Memorial University of Newfoundland Phone: ; Fax: merline.fonkwe@mun.ca

3 TABLE OF CONTENTS Page LIST OF FIGURES...ii LIST OF TABLES... iii ACKNOWLEDGEMENTS... iv EXECUTIVE SUMMARY... v 1. INTRODUCTION: RATIONAL AND OBJECTIVES SAMPLE COLLECTION, PRESERVATION AND ANALYSES RESULTS AND DISCUSSION Physical parameters Temperature ph Electrical conductivity Total dissolved solids Oxidation-reduction potential Chemical parameters Anions and nutrients Alkalinity Chloride Fluoride Sulfate Total hardness Major and trace elements Naturally-occurring elements Plumbing corrosion-induced metals CONCLUSIONS RECOMMENDATIONS REFERENCES i

4 LIST OF FIGURES Figure 1: Map (from Google Earth) showing the location of Birch Brook Ski Club near the Town of Happy Valley-Goose Bay, on highway Figure 2: Research assistant, Danielle Spearing in action at the Chalet s kitchen on July 27, (A) She collects water sample in plastic bottles from the cold-water faucet for the determination of the chemical parameters. (B) She measures the physical parameters of water in a plastic laboratory beaker... 3 Figure 3: Seasonal levels of total dissolved solids in flushed samples (labelled 1) during the sampling period... 7 Figure 4: Seasonal concentrations of chloride, fluoride and sulfate in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period... 9 Figure 5: Seasonal levels of total hardness in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period. The classification of the hardness in drinking water is shown Figure 6: Seasonal concentrations of barium, boron, calcium, magnesium, silicon, sodium and strontium in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period Figure 7: Seasonal concentrations of copper and zinc in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period Page ii

5 LIST OF TABLES Table 1: Physical and chemical analytical results of drinking water from untreated groundwater well at the Birch Brook chalet... 4 Page iii

6 Acknowledgements This research was supported by the Harris Centre of Memorial University through an RBC Water Research and Outreach Fund, Atlantic Canada Opportunities Agencies (ACOA), and the Department of Business, Tourism, Culture, and Rural Development, Newfoundland and Labrador (BTCRD NL). Special thanks are extended to Betty-Anne Fequet, Graham Moorhouse and John Bookalam for access to the Birch Brook Ski chalet, and the research assistants Daniel Frawley and Danielle Spearing, for their assistance during water sampling. The research assistant, Danielle Spearing participated in this project thanks to the generous support of the Women in Science and Engineering Student Summer Employment Program (WISE SSEP 2015); WISE NL is gratefully acknowledged. iv

7 Executive summary This report presents the results of physical and chemical analyses of drinking water at the chalet, belonging to Birch Brook Ski Club. This club is located at about 21 km from the town of Happy Valley-Goose Bay in Labrador, on highway 520 (also called North West River Road). Birch Brook chalet uses drinking water, supplied by untreated groundwater from a private well. Some club members have indicated that they drink the Birch Brook chalet s tap water as an alternative to municipally supplied water in Happy Valley-Goose Bay. Therefore, drinking water from the Birch Brook chalet was part of the research project focusing on various physical and chemical parameters of drinking water quality in town of Happy Valley-Goose Bay. Water from the kitchen cold-water faucet was sampled and analyzed in winter, spring, summer and fall At each visit at the chalet, two sample types ( first draw and flushed ) were collected to ensure that seasonal and in-chalet changes could be adequately described. Physical parameters (temperature, ph, electrical conductivity, total dissolved solids and oxidationreduction potential) were measured for flushed samples only. On the other hand, anions and nutrients (alkalinity, bromide, chloride, fluoride, nitrate-nitrogen, nitrite-nitrogen, orthophosphatephosphorus and sulfate), and major and trace elements (aluminum, antimony, arsenic, barium, beryllium, bismuth, boron, cadmium, calcium, cesium, chromium, cobalt, copper, iron, lead, lithium, magnesium, manganese, molybdenum, nickel, phosphorus, potassium, rubidium, selenium, silicon, silver, sodium, strontium, sulfur, tellurium, thallium, thorium, tin, titanium, tungsten, uranium, vanadium, zinc and zirconium) were determined for both first draw and flushed samples. The obtained physical and chemical parameters were all within health- and aesthetic- based guidelines set by Health Canada and the NL provincial government. In general, their seasonal variations were insignificant. Drinking water classified as fresh, soft (low content of dissolved minerals) and alkaline, and reflected oxidizing groundwater conditions (i.e. positive oxidationreduction potential). Although naturally-occurring in groundwater supply well, the levels of fluoride in drinking water was still lower than optimal for the promotion of dental health. Amongst the major and trace elements detected, barium, boron, calcium, magnesium, silicon, sodium and strontium showed relative constant variation between first-draw samples and flushed samples. This suggests that they are most likely from natural sources. Moreover, sodium displayed concentrations higher in summer and fall than in winter and spring, whereas concentrations of barium, boron, calcium, magnesium, silicon and strontium varied slightly between the seasons. On the other hand, concentrations of copper and zinc varied considerably v

8 between first-draw samples and flushed samples. This indicates that plumbing materials that are in contact with drinking water contributed to a minor extent to copper and zinc concentrations in drinking water. However, flushing the plumbing system lowered the amounts of copper and zinc in drinking water. In addition to the reported physical and chemical parameters, other aspects of drinking water quality (e.g. microbiological characteristics, etc.) should also be investigated, in order to assess the overall water quality at the chalet of Birch Brook Ski Club. Ideally, testing should be done on a regular basis to track changes (if any) in groundwater quality over time. Because of the intermittent use of the chalet and therefore its tap water, there is a potential for the presence of elevated levels of copper and zinc in the water. For this reason, when water has not been used for an extended period of time, the plumbing system should be flushed before using the water for drinking. vi

9 1. Introduction: rational and objectives A research project on various physical and chemical qualities of municipally-supplied drinking water in town of Happy Valley-Goose Bay was conducted at the Labrador Institute of Memorial University (see Fonkwe, 2016; Fonkwe and Schiff, 2016). As part of this project, drinking water of the chalet belonging to the Birch Brook Nordic Ski Club was also analyzed, because some club members have indicated that they drink the chalet s tap water as an alternative to municipally supplied water in Happy Valley-Goose Bay. Birch Brook Nordic Ski Club is located at about 21 km from the town of Happy Valley-Goose Bay, on highway 520 or North West River Road (Fig. 1). Its chalet gets its drinking water directly from untreated groundwater through a private well, which is 370 feet deep (G. Moorhouse pers. comm., July 27, 2015). Figure 1: Map (from Google Earth) showing the location of Birch Brook Ski Club near the Town of Happy Valley-Goose Bay, on highway 520. Note: (Top) An inset picture of the Birch Brook Chalet. (Right) An inset map shows the position of the town of Happy Valley-Goose Bay in Labrador and in Canada. 1

10 The objectives of this study were to: (i) determine various physical and chemical characteristics of drinking water at the Birch Brook chalet, and whether there were seasonal and in-chalet variations; and (ii) compare each parameter with the standard value set by Heath Canada and provincial drinking water quality guidelines. 2. Water sample collection, preservation and analyses Drinking water was sampled and analyzed in March, June, July and October 2015 during each of the four seasons, as divided under the Drinking Water Quality Monitoring and Reporting for Public Water Supplies in Labrador by the NL Department of Environment and Climate Change. The collection of the water samples was done by Dr. Merline Fonkwe and her research assistants Daniel Frawley and Danielle Spearing. Water samples were collected from the kitchen cold-water faucet, because this is where water is mainly drawn for drinking. The focus was on the determination of physical parameters, and chemical parameters, including 8 anions and nutrients and 39 major and trace metals (see Table 1). During each visit at the chalet, four tasks were completed: 1. Collection of two first-draw samples (one for anions and nutrients, and the other one for major and trace elements) in plastic bottles. First-draw sample represented water, which has been sitting in the plumbing system for extended period of time (approximately six hours or more). This sample was analyzed to evaluate whether the quality of tap water was affected by materials of the plumbing system. 2. Running the cold water faucet for 30 minutes to flush out the stagnant water in contact with the pipes and other plumbing fixtures. 3. Collection of two flushed samples (one for anions and nutrients, and the other one major and trace elements) in plastic bottles. Flushed sample represented water freshly drawn from the well. This sample was analyzed to determine the actual chemical composition of the groundwater (i.e. without the influence of plumping materials) (see Fig 1A). 4. Measurement of physical parameters (ph, temperature (T C), electrical conductivity (EC), total dissolved solids (TDS) and oxidation-reduction potential (ORP)) immediately after the collection of flushed samples, because they are unstable and change during storage and transport. A Hanna Instruments (HI) multiprobe HI meter was used for ph, T C and TDS, whereas an HI meter was used for ORP (see Fig. 1B; Table 1). 2

11 As soon as sampling was completed, the sample bottles were placed in an iced cooler container and transported to the Labrador Institute Research Station Laboratory in North West River for re-icing, packing, and shipping for analysis to ALS Environmental laboratory (Mississauga, Canada). Figure 2: Research assistant, Danielle Spearing in action at the Chalet s kitchen on July 27, (A) She collects water sample in plastic bottles from the cold-water faucet for the determination of the chemical parameters. (B) She measures the physical parameters of water in a plastic laboratory beaker. Water samples for anions and nutrients were collected in 250 ml High Density Polyethylene (HDPE) plastic bottles. Analysis of anions was done by ion chromatography following the United State Environmental Protection Agency (U.S. EPA) method (Pfaff, 1993), except that orthophosphate content was determined by a colorimetric technique, following the American Public Health Association (APHA) Method 4500-P B.E. (APHA, 1999). Water alkalinity (as CaCO3) was determined by autoanalyzer following the U.S. EPA method (U.S. EPA, 1974). The obtained concentrations for anions and nutrients are reported in milligrams per liter (mg/l) (see Table 1). Water samples for major and trace elements were collected in 125 ml HDPE plastic bottles containing 1.5mL of 18% nitric acid (HNO3) for immediate adjustment of the sample ph to less than 2, in order to preserve trace metals and reduce precipitation, microbial activity and sorption losses to sampling container walls. Analysis was done by inductively coupled plasma mass spectroscopy (ICP-MS), following the U.S. EPA method (U.S. EPA, 1994). The obtained concentrations of total metals are in mg/l (see Table 1). 3. Results and discussion Physical and chemical parameters of the chalet s drinking water were determined on a seasonal basis to assess their physical properties and the concentrations of chemical constituents, and their 3

12 Table 1: Physical and chemical analytical results of drinking water from untreated groundwater well at the Birch Brook chalet (continue on next page). * Guidelines for aesthetic (taste, smell or appearance) or health-risk levels (Health Canada, 2014; 2015). : Less than or equal to; : Not applicable; C: degree Celsius; µs/cm: microsiemens per centimeter; ppm: part per million; mv: millivolt; < with a value : indicates that that element was analyzed, but that its level is below the detection limit of the instrumental method. Health Canada and NL guidelines* First draw sample WINTER SPRING SUMMER FALL PHYSICAL PARAMETERS Temperature (T) in C 15 C ph Electrical conductivity (EC) in µs/cm Total dissolved solids (TDS) in ppm Oxidation-reduction potential (ORP) in mv ANIONS AND NUTRIENTS (concentrations in mg/l) Alkalinity (as CaCO3) Bromide (Br ) <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 Chloride (Cl ) Fluoride (F) Nitrate (as N) 10 <0.020 <0.020 <0.020 <0.020 <0.020 <0.020 <0.020 <0.020 Nitrite (as N) 1 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 Phosphate-P (ortho) < < < < < < Sulphate (SO4 ) Total Hardness (as CaCO3, calculated) None TOTAL MAJOR AND METALS (concentrations in mg/l) Aluminum (Al) None <0.010 <0.010 < <0.010 <0.010 <0.010 <0.010 Antimony (Sb) < < < < < < < < Arsenic (As) < < < < < < < < Barium (Ba) Beryllium (Be) < < < < < < < < Bismuth (Bi) < < < < < < < < Boron (B) Cadmium (Cd) < < < < < < < Calcium (Ca) None Cesium (Cs) < < < < < < < < Chromium (Cr) 0.05 < < < < < < Cobalt (Co) < < < < < < < < Flushed sample First draw sample Flushed sample First draw sample Flushed sample First draw sample Flushed sample 4

13 Copper (Cu) Iron (Fe) 0.3 <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 Lead (Pb) < < Lithium (Li) <0.10 <0.10 <0.10 <0.10 <0.10 < Magnesium (Mg) None Manganese (Mn) 0.05 < < < < < Molybdenum (Mo) Nickel (Ni) < < < < < < < Phosphorus (P) <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 Potassium (K) < Rubidium (Rb) < < < < < < Selenium (Se) 0.05 < < < < < < < < Silicon (Si) Silver (Ag) None < < < < < < < < Sodium (Na) Strontium (Sr) Sulfur (S) <5.0 <5.0 <5.0 <5.0 <5.0 <5.0 <5.0 <5.0 Tellurium (Te) < < < < < < < < Thallium (Tl) < < < < < < < < Thorium (Th) < < < < < < < < Tin (Sn) < < < < Titanium (Ti) < < < < < < Tungsten (W) <0.010 <0.010 <0.010 <0.010 <0.010 < Uranium (U) 0.02 < < < < < < Vanadium (V) < < < Zinc (Zn) < Zirconium (Zr) < < < < < < < <

14 seasonal and in-chalet variations. The analytical results for the measured parameters of drinking water samples are presented in Table 1, together with the health- and aesthetic-based drinking water quality guidelines set by Health Canada and NL provincial government (Health Canada, 2014: 2015) Physical parameters Temperature Temperature of drinking water across the seasons varied between 10.7 C and 15.9 C (Table 1). The highest value obtained in fall, probably also due the fact that the period of water stagnancy in the plumbing system was longer than during the other seasons. The Health Canadia and provincial aesthetic-based guideline value of drinking water temperature is less than or equal to 15 C (Health Canada, 2014). Although the water temperature does not have direct health effects, it remains nonetheless an important determinant of water quality because of its influence on chemical and biological proprieties of drinking water (Health Canada, 2014; Liu et al., 2013) ph Water ph varied slightly between the seasons and ranged between 8.8 and 9.5 (Table 1). This clearly indicates the alkaline nature of the groundwater. Thus, the ph of the groundwater does not contribute to high concentrations of metals, which affect the quality of drinking water. All the samples fall within the desirable ph range of for drinking water (Health Canada, 2015) Electrical Conductivity Electrical conductivity (EC) is commonly used as a good indicator of the relative amount of salts in water. The EC values varied between 132 and 863 µs/cm, with the highest values observed in fall and summer (Table 1). Rao et al. (2012) have classified EC as Type I, if the enrichments of salts are low (EC<1500 µs/cm); Type II, if the enrichment of salts are medium (EC between 1500 and 3000 µs/cm); and Type III, if the enrichments of salts are high (EC>3000 µs/cm). Based on the above classification, all the samples fall within Type I low enrichment of salts Total Dissolved Solids Total dissolved solids (TDS) includes inorganic constituents (salts) and organic matter. Based on Health Canada and provincial standards, TDS value up to 500 ppm is the highest desirable level in drinking water. The obtained TDS values varied between a minimum of 65 ppm in winter and a maximum of 395 ppm in fall (Fig. 3; Table 1). This indicates that all the samples lies within the 6

15 maximum permissible limit for drinking purpose. Based on TDS classification of Freeze and Cherry (1979), the drinking water at the Birch brook classified as freshwater. Figure 3: Seasonal levels of total dissolved solids in flushed samples (labelled 1) during the sampling period Oxidation-Reduction Potential Oxidation-reduction potential (ORP) or redox potential measures the capacity of water to either lose (oxidation) or gain (reduction) electrons from chemical (redox) reactions. It indicates the oxidizing (aerobic) or reducing (anaerobic) tendency of water; positive values indicate oxidizing conditions, while negative values occur when the water is more reducing. Redox potential of groundwater controls important processes, such as mobilization and immobilization of metals (or contaminants) from both natural and anthropogenic sources (e.g. McMahon and Chapelle, 2008). The ORP level of the drinking water was found to be low in fall with a level of 40 mv, whereas the values in winter, spring and summer were high, ranging between 216 and 248 mv. Positive ORP values observed in all the seasons suggest relative oxidizing environment of groundwater and low organic matter content. 7

16 3.2. Chemical parameters The chemical parameters of water determined consist of: (i) anions and nutrients, including alkalinity, bromide, chloride, fluoride, nitrate-nitrogen, nitrite-nitrogen, orthophosphatephosphorus and sulphate; and (ii) major and trace elements, including aluminum, antimony, arsenic, barium, beryllium, bismuth, boron, cadmium, calcium, cesium, chromium, cobalt, copper, iron, lead, lithium, magnesium, manganese, molybdenum, nickel, phosphorus, potassium, rubidium, selenium, silicon, silver, sodium, strontium, sulfur, tellurium, thallium, thorium, tin, titanium, tungsten, uranium, vanadium, zinc and zirconium (Table 1). In addition, total hardness of drinking water was calculated and the values are also given in Table Anions and nutrients Bromide, nitrate-nitrogen, nitrite-nitrogen, orthophosphate-phosphorus were not present in detectable levels (i.e. obtained concentrations were below their lower limits of detection) or were present only at very low concentrations in all samples (Table 1). Their levels in drinking water were considered to be negligible. Therefore, only the results of alkalinity, chloride, fluoride and sulfate given in Table 1 are discussed here Alkalinity Alkalinity (as CaCO3) measures water s capacity to resist to ph changes. Adequate alkalinity, typically above 100 mg/l, will protect ph from fluctuation and therefore, will keep it stable. Alkalinity is primarily a function of the presence of naturally-occurring carbonates, bicarbonates and to a lesser degree, hydroxides and phosphates (e.g. Briggs and Ficke, 1977). It is influenced by local geology and by the percolation of rain and surface water along with the dissolved carbon dioxide of the atmosphere. Alkalinity is a commonly used indicator in the interpretation and control of water processes. Alkalinity (as CaCO3) values of drinking water varied slightly between the seasons, ranging between 64 and 79 mg/l (Table 1). Lower alkalinity was observed in spring and winter, whereas higher values occurred in summer and fall. First-draw and flushed samples showed narrow variation ranges Chloride Chloride varied slight between the seasons, and between first-draw and flushed samples. Concentrations of chloride ranged between 0.89 and 1.27 mg/l (Fig. 4; Table 1). The chloride levels in drinking water were very well below the Health Canada (2014) aesthetic-based guideline of 250 8

17 mg/l, established due to the salty taste concern above that limit. This indicates lower concentration of salts in groundwater Fluoride Fluoride occurs naturally in groundwater due to leaching from many types of sedimentary and igneous rocks. The recommended concentration for fluoride in drinking water is 1.5 mg/l (Heath Canada, 2014). Fluoride in drinking water at level of 0.7 mg/l help promote dental health in both children and adults. (e.g. Griffin et al., 2007; Loskill et al., 2013; Rabb-Waytowich, 2009; Yeung, 2007; World Health Organization, 2004). All the samples contained naturally-occurred fluoride at levels from 0.19 to 0.44 mg/l (Fig. 4; Table 1). Although the concentrations of fluoride in drinking water were well below the aesthetic-based desirable limit, they still too low for optimal promotion of dental health. Figure 4: Seasonal concentrations of chloride, fluoride and sulfate in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period Sulfate Sulfate occurs naturally in groundwater and from the dissolution and/or oxidation of sulfate minerals in mineral deposits, soils and rocks (e.g. shales), from seawater intrusion, or due to 9

18 human activities, such as power plants and industrial wastes (e.g., Krouse and Mayer, 1999; Seller and Canter, 1980). Seasonal levels of sulfate in drinking water ranged between 8.41 and 14.5 mg/l (Fig. 4; Table 1). First-draw and flushed samples showed moderate variation ranges. Sulfate levels are within the recommended limit of 500 mg/l, set in order to avoid possible adverse effects on the taste of drinking water (Health Canada, 2014) Total hardness Water hardness is caused primarily by the presence of dissolved calcium- and magnesium salts, bicarbonates and hydroxides (namely carbonate hardness) and dissolved noncarbonated salts, calcium- and magnesium- chlorides and sulphates (namely non-carbonate hardness) with to some extent, several other dissolved metals forming divalent or multivalent cations, such as aluminum, barium, strontium, iron, zinc, and manganese in water. Carbonate hardness is equivalent to total alkalinity and any excess of hardness above total alkalinity is considered to be non-carbonate hardness (e.g. Rice et al., 2012). Total hardness (as CaCO3) of drinking water was calculated using the formula below: Total hardness as CaCO3 (mg/l) = [Ca, mg/l] [Mg, mg/l] Total hardness of drinking water showed a moderate variation range of 17 to 24 mg/l between the seasons, with the highest value recorded in winter (Fig. 5; Table 1). According to Durfor and Becker (1964) and Health Canada (1979) classification of total hardness, all the samples fall within soft water type (see Fig. 5). This indicates lower concentration of salts in groundwater. There is no health related guideline value for total hardness. To minimise undesirable build-up of off-white chalky scale in plumbing system and water use appliance, total hardness in drinking water should not exceed 100mg/L (Health Canada, 2014) Major and trace metals The following elements were either not detected (obtained concentrations were below their limits of detection) or were present only in trace quantities (concentrations were close to their limits of detection) in drinking water samples: aluminum, antimony, arsenic, beryllium, bismuth, cadmium, cesium, chromium, cobalt, iron, lead, lithium, manganese, molybdenum, nickel, phosphorus, potassium, rubidium, selenium, silver, sulfur, tellurium, thallium, thorium, tin, titanium, tungsten, uranium, vanadium, and zirconium (Table 1). Therefore, their levels in drinking water were considered to be insignificant. 10

19 Figure 5: Seasonal levels of total hardness in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period. The classification of the hardness in drinking water is shown. Elements actually detected in the analyzed water samples have been divided into two groups, based on their origins: (i) naturally-occurring elements, including barium, boron, calcium, magnesium, silicon, sodium, strontium; and (ii) plumbing corrosion-induced metals, including copper and zinc Naturally-occurring elements The variations of barium, boron, calcium, magnesium, silicon, sodium and strontium in groundwater samples are presented in Figure 6. The concentrations of barium ( mg/l), boron ( mg/l), calcium ( mg/l), magnesium ( mg/l), silicon ( mg/l) and strontium ( mg/l) varied slightly between the seasons. In contrast, seasonal variation of sodium in drinking water was more pronounced. Sodium levels in winter and spring were lower (24.0 and 27.8 mg/l, respectively) that in summer and fall (37.3 and 41.1 mg/l, respectively). The relative constant concentrations of barium, boron, calcium, magnesium, silicon, sodium and strontium in first-draw and flushed samples suggest that they are most likely from natural sources. 11

20 Figure 6: Seasonal concentrations of barium, boron, calcium, magnesium, silicon, sodium and strontium in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period. Note: (Top) An inset graph shows the details of the low concentration range. 12

21 There are no documented adverse health effects due to the presence of calcium, magnesium, silicon and strontium in drinking water and, therefore, no guidelines values have been issued for these elements (Health Canada, 2014). An aesthetic-based guideline level has been established at 200 mg/l for sodium (Health Canada, 1992: 2014), because of possible noticeable salty taste at higher concentrations. On the other hand, health- based guideline or maximum acceptable limit has been issued for barium (1.0 mg/l), because of increases in blood pressure and cardiovascular disease. (Health Canada, 2014). Similarly, health- based guideline is set for boron (5 mg/l), because of reproductive effects (Health Canada, 2014). The obtained levels of sodium, barium and boron in drinking water at the Birch Brook chalet were well below the aesthetic- or health- based guidelines Plumbing corrosion-induced metals Copper and zinc were found at low concentrations, between mg/l and < mg/l, respectively (Fig. 7). The levels of copper and zinc in first-draw samples were higher than in flushed samples. This indicates that they are more likely released from plumbing materials due to the stagnation of water in the plumbing system for an extended period of time. Nevertheless, their concentrations were still below the aesthetic-based guideline value of 1.0 mg/l for copper and 5.0 mg/l for zinc (Health Canada, 2014). At levels at or above the guideline, copper can give a bitter, metallic taste to tap water. On the other hand, zinc can cause potential problems associated with taste, milky appearance (opalescence), and the formation of greasy films at water surface upon boiling. Flushing the plumbing system reduced copper and zinc levels in drinking water. 4. Conclusions The following conclusions can be drawn from these results: The physical and chemical parameters of drinking water varied slightly between the seasons. Drinking water classified as fresh, soft (low content of dissolved minerals) and alkaline, and reflected oxidizing groundwater conditions (i.e. positive ORP). Although naturally-occurring in groundwater, the levels of fluoride in drinking water was still lower than optimal for the promotion of dental health. The elements with the relative constant variation between first-draw samples and flushed samples in drinking water were barium, boron, calcium, magnesium, silicon, sodium and strontium, all most probably originating from natural sources. Except for 13

22 sodium with concentrations higher in summer and fall than in winter and spring, the levels of the other elements varied slightly between the seasons. Figure 7: Seasonal concentrations of copper and zinc in first-drawn samples (those labelled 0) and flushed samples (those labelled 1) during the sampling period. Copper and zinc showed considerable variations, especially between first-draw samples and flushed samples, indicating that they were released from plumbing materials due to long periods of water stagnation in the plumbing system; their variations between the seasons were insignificant. Flushing the stagnant water in the plumbing system lower the levels of copper, and also zinc in drinking water. The obtained physical and chemical parameters were all within health- and aestheticbased guidelines, which have been set by Health Canada and NL provincial government. 14

23 5. Recommendations The following recommendations for better ensuring the safety of drinking water are offered, based these results: Other aspects of drinking water quality (e.g. microbiological characteristics, etc.) should also be investigated. Testing should be done on a regular basis to assess whether the quality of groundwater changes over time. The plumbing system should be flushed before use for drinking anytime water has not been used for an extended period of time. 15

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