MWS-Report

Appendix B5: Historical Baseline Threshold Exceedances

  Lower Baseline Threshold Upper Baseline Threshold Method Exceedance Year Exceedance Value Exceedance Season Exceedance Amount
Calcium (mg/L)              
Daring Lake 0.40 2.96 TIF 2008-09-03 6.1 Open Water 3.14
        2009-03-26 3 Under Ice 0.04
        2010-07-06 6 Open Water 3.04
        2015-03-27 5.9 Under Ice 2.94
Desteffany Lake 0.50 2.91 TIF 2008-09-03 3.6 Open Water 0.69
Lac de Gras 0.60 2.75 TIF 2009-03-26 2.9 Under Ice 0.25
        2013-03-25 2.8 Under Ice 0.05
Rocknest Lake 1.00 7.00 TIF 2008-09-03 12.9 Open Water 5.9
        2019-07-10 8.6 Open Water 1.6
Chloride (mg/L)              
Daring Lake - - - - - - -
Desteffany Lake 0.25 1.45 TIF 2014-03-21 1.5 Under Ice 0.05
        2014-03-21 1.5 Under Ice 0.05
        2016-03-23 1.7 Under Ice 0.25
        2016-03-23 2 Under Ice 0.55
        2017-03-23 1.8 Under Ice 0.35
        2018-03-13 2 Under Ice 0.55
        2018-03-13 2.1 Under Ice 0.65
        2019-03-18 2.1 Under Ice 0.65
Lac de Gras 0.20 2.81   2000-12-14 3.6 Under Ice 0.79
Rocknest Lake - - - - - - -
Hardness, as CaCO3 (mg/L)              
Daring Lake 1.90 12.09 TIF 2008-09-03 22.4 Open Water 10.31
        2015-03-27 27.3 Under Ice 15.21
        2018-09-05 20.1 Open Water 8.01
Desteffany Lake 2.40 13.80 TIF 2018-09-05 26.1 Open Water 12.3
Lac de Gras 0.29 14.07 TIF 2004-07-08 0.007 Open Water -0.28
        2018-09-05 29.9 Open Water 15.83
Rocknest Lake 5.10 24.95 TIF 2008-09-03 46.2 Open Water 21.25
        2018-09-05 30.6 Open Water 5.65
        2019-07-10 34.6 Open Water 9.65
        2019-08-08 25 Open Water 0.05
Magnesium (mg/L)              
Daring Lake 0.20 1.39 TIF 2008-09-03 1.7 Open Water 0.3125
        2010-07-06 2.4 Open Water 1.01
        2015-03-27 3.1 Under Ice 1.71
        2018-09-05 4.4 Open Water 3.01
Desteffany Lake 0.30 1.70 TIF 2018-09-05 5.8 Open Water 4.1
Lac de Gras 0.40 1.70 TIF 2018-09-05 6.7 Open Water 5
Rocknest Lake 0.60 2.50 TIF 2008-09-03 3.4 Open Water 0.9
        2018-09-05 6.5 Open Water 4.1
        2019-07-10 3.2 Open Water 0.7
Potassium (mg/L)              
Daring Lake 0.20 0.90 TIF 2004-03-19 1.37 Under Ice 0.47
        2015-03-27 2.3 Under Ice 1.4
Desteffany Lake 0.30 1.00 TIF 2001-04-24 2.19 Under Ice 1.19
Lac de Gras 0.30 1.00 TIF 2018-03-13 1.1 Under Ice 0.1
Rocknest Lake 0.30 0.65 TIF 2008-03-31 0.7 Under Ice 0.05
        2009-03-26 0.7 Under Ice 0.05
        2018-03-13 0.8 Under Ice 0.15
Sodium (mg/L)              
Daring Lake 0.30 1.00 TIF 2004-03-19 1.4 Under Ice 0.4
        2011-03-23 1.1 Under Ice 0.1
        2015-03-27 3 Under Ice 2
Desteffany Lake 0.33 1.69 TIF 2001-04-24 2.19 Under Ice 0.41
        2009-09-10 0.3 Open Water -0.03
Lac de Gras 0.35 2.10 TIF n/a n/a n/a n/a
Rocknest Lake 0.40 1.00 TIF n/a n/a n/a n/a
Sulphate (mg/L)              
Daring Lake 1.00 3.50 TIF 2015-03-27 9 Under Ice 5.5
Desteffany Lake 1.00 4.50 TIF 2004-02-03 10 Under Ice 5.5
Lac de Gras 0.50 4.50 TIF 2001-10-04 0.3 Open Water -0.2
        2004-02-03 10 Under Ice 5.5
        2004-10-13 6 Open Water 1.5
        2018-03-13 5 Under Ice 0.5
        2019-03-18 5 Under Ice 0.5
Rocknest Lake 2.00 2.00 TIF 2007-07-06 1 Open Water -1
        2008-03-31 3 Under Ice 1
        2008-07-07 4 Open Water 2
        2009-03-26 3 Under Ice 1
        2016-03-23 3 Under Ice 1
        2016-09-07 3 Open Water 1
        2017-03-23 3 Under Ice 1
        2017-08-09 3 Open Water 1
        2018-03-13 4 Under Ice 2
        2018-07-11 3 Open Water 1
        2019-03-18 3 Under Ice 1
        2019-09-05 3 Open Water 1
Total Alkalinity, as CaCO3 (mg/L)              
Daring Lake 2.60 7.70 TIF 2004-03-19 9.3 Under Ice 1.6
        2015-03-27 22.3 Under Ice 14.6
Desteffany Lake 2.40 13.80 TIF 2002-08-28 41.4 Open Water 27.6
        2003-03-25 34.9 Under Ice 21.1
        2009-09-10 1.5 Open Water -0.9
Lac de Gras 1.45 6.80 TIF 2009-09-10 1.2 Open Water -0.25
Rocknest Lake 4.20 12.34 M2MAD 2007-07-06 18.9 Open Water 6.56
        2008-08-06 17 Open Water 4.66
        2009-08-05 13.3 Open Water 0.96
        2009-09-10 13.8 Open Water 1.46
        2010-08-10 15.5 Open Water 3.16
        2015-09-03 20.6 Open Water 8.26
        2019-07-10 37.1 Open Water 24.76
        2019-08-08 25.4 Open Water 13.06
Dissolved Organic Carbon (DOC) (mg/L)              
Daring Lake 1.30 3.85 TIF 2004-03-19 4.4 Under Ice 0.55
        2015-03-27 7.3 Under Ice 3.45
Desteffany Lake 2.20 4.38 TIF n/a n/a n/a n/a
Lac de Gras 1.60 3.55 TIF 2004-03-19 3.6 Under Ice 0.05
        2013-03-25 3.6 Under Ice 0.05
        2014-03-21 3.9 Under Ice 0.35
Rocknest Lake 2.30 4.85 TIF 2007-07-06 4.9 Under Ice 0.05
        2019-07-10 7 Under Ice 2.15
        2019-08-08 4.9 Under Ice 0.05
Total Nitrogen (Nitrate/Nitrite), as N (mg/L)              
Daring Lake 0.01 0.02 M2MAD 2004-03-19 0.10 Under Ice 0.08
        2004-05-19 0.20 Spring Freshet 0.18
        2008-07-07 0.12 Open Water 0.1
        2008-08-06 0.12 Open Water 0.1
        2010-07-06 0.14 Open Water 0.12
        2010-08-10 0.10 Open Water 0.08
        2010-09-01 0.04 Open Water 0.02
        2014-07-08 0.03 Open Water 0.01
        2014-09-09 0.04 Open Water 0.02
        2015-03-27 0.39 Under Ice 0.37
Desteffany Lake 0.01 0.04 TIF 2003-03-25 0.04 Under Ice 0.003
        2006-07-04 0.30 Spring Freshet 0.26
        2008-07-07 0.12 Open Water 0.08
        2008-08-06 0.11 Open Water 0.07
        2010-07-06 0.15 Open Water 0.11
        2010-08-10 0.10 Open Water 0.06
        2011-03-23 0.05 Under Ice 0.01
        2015-03-27 0.06 Under Ice 0.02
Lac de Gras 0.01 0.02 TIF - - - -
Rocknest Lake 0.01 0.12 TIF 2008-07-07 0.26 Open Water 0.14
        2008-08-06 0.42 Open Water 0.3
        2010-07-06 0.15 Open Water 0.03
Total Phosphorus (mg/L)              
Daring Lake 0.00 0.02 TIF 2007-08-17 0.03 Open Water 0.01
Desteffany Lake 0.00 0.02 TIF 2002-08-28 0.051 Open Water 0.031
        2002-10-17 0.061 Open Water 0.041
Lac de Gras 0.00 0.02 TIF 2000-12-14 0.05 Under Ice 0.03
        2001-08-27 0.02 Open Water 0.001
        2002-08-28 0.06 Open Water 0.04
        2002-10-17 0.06 Open Water 0.04
        2004-10-13 0.09 Open Water 0.07
Rocknest Lake 0.00 0.02 TIF n/a n/a n/a n/a
Specific Conductivity (µS/cm)              
Daring Lake 8.50 24.85 TIF 2004-03-19 31.9 Under Ice 7.05
        2015-03-27 74.9 Under Ice 50.05
Desteffany Lake 12.00 28.68 TIF 2018-03-13 31.3 Under Ice 2.62
        2019-03-18 30.3 Under Ice 1.62
Lac de Gras 12.40 32.51 TIF 2018-03-13 37.3 Under Ice 4.79
        2019-03-18 34.8 Under Ice 2.29
Rocknest Lake 18.00 30.31 M2MAD 2007-07-06 42.3 Open Water 11.99
        2008-08-06 40.3 Open Water 9.99
        2009-08-05 32.9 Open Water 2.59
        2010-08-10 38.3 Open Water 7.99
        2015-09-03 45 Open Water 14.69
        2019-07-10 72.7 Open Water 42.39
        2019-08-08 49.3 Open Water 18.99
Total Dissolved Solids (TDS) (mg/L)              
Daring Lake 10.00 20.00 TIF 2007-07-06 22 Open Water 2
        2015-03-27 45 Under Ice 25
        2016-07-07 22 Open Water 2
        2019-09-05 64 Open Water 44
Desteffany Lake 10.00 25.00 TIF 2002-10-17 32 Open Water 7
        2008-03-31 84 Under Ice 59
        2016-07-07 31 Open Water 6
        2018-03-13 30 Under Ice 5
        2019-09-05 70 Open Water 45
Lac de Gras 10.00 25.00 TIF 2000-07-25 35 Open Water 10
        2001-07-25 53 Open Water 28
        2002-10-17 39 Open Water 14
        2016-03-23 26 Under Ice 1
        2016-07-07 29 Open Water 4
        2018-03-13 28 Under Ice 3
        2018-09-05 28 Open Water 3
        2019-09-05 74 Open Water 49
Rocknest Lake 10.00 45.00 TIF 2019-09-05 88 Open Water 43
Turbidity (NTU)              
Daring Lake 0.15 0.41 M2MAD 2004-03-19 3.31 Under Ice 2.69
        2004-05-19 0.59 Spring Freshet 0.18
        2004-07-08 1.04 Open Water 0.63
        2008-09-03 0.44 Open Water 0.03
        2009-03-26 0.67 Under Ice 0.26
        2012-03-27 1.16 Under Ice 0.75
        2012-08-08 0.52 Open Water 0.11
        2013-03-27 0.12 Under Ice -0.03
        2013-07-09 0.57 Open Water 0.16
        2013-08-07 0.57 Open Water 0.16
        2013-09-06 0.63 Open Water 0.22
        2014-03-21 0.43 Under Ice 0.02
        2015-03-27 0.42 Under Ice 0.01
        2015-09-03 0.57 Open Water 0.16
        2016-03-23 1.42 Under Ice 1.01
        2017-03-23 2.41 Under Ice 2
        2019-03-18 0.12 Under Ice -0.03
Desteffany Lake 0.10 0.86 TIF 2001-03-14 1 Under Ice 0.14
        2002-10-17 1.7 Open Water 0.84
        2004-05-19 3.23 Spring Freshet 2.37
        2004-07-08 2.07 Open Water 1.21
        2009-03-26 1.35 Under Ice 0.49
        2016-03-23 1.19 Under Ice 0.33
        2017-03-23 1.2 Under Ice 0.34
Lac de Gras 0.10 0.70 TIF 2000-04-13 0.9 Under Ice 0.2
        2001-04-24 1.2 Under Ice 0.5
        2002-10-17 1 Open Water 0.3
        2004-03-19 2.4 Under Ice 1.7
        2006-01-31 0.92 Under Ice 0.22
        2009-03-26 1.9 Under Ice 1.2
Rocknest Lake 0.11 0.59 TIF 2007-09-13 1.52 Open Water 0.93
        2009-03-26 1.7 Under Ice 1.11
        2013-07-09 0.73 Open Water 0.14
        2013-08-07 0.72 Open Water 0.13
pH (unitless)              
Daring Lake 6.31 6.94 TIF 2010-03-23 6.28 Under Ice -0.03
        2015-03-27 6.06 Under Ice -0.25
Desteffany Lake 6.30 6.97 TIF 2004-02-03 6.04 Under Ice -0.26
        2010-03-23 6.28 Under Ice -0.02
Lac de Gras 6.39 7.06 TIF n/a n/a n/a n/a
Rocknest Lake 6.37 7.79 TIF n/a n/a n/a n/a
Aluminum (μg/L)              
Daring Lake 2.70 13.64 TIF 2003-05-01 30 Spring Freshet 16.36
        2006-03-22 30 Under Ice 16.36
        2008-07-07 21.1 Open Water 7.46
        2012-03-27 58.5 Under Ice 44.86
        2015-08-06 28.8 Open Water 15.16
        2015-09-03 18.9 Open Water 5.26
Desteffany Lake 4.00 34.98 TIF 2002-08-28 35 Open Water 0.02
        2004-07-08 42.2 Open Water 7.22
        2006-07-04 78 Open Water 43.02
Lac de Gras 1.00 14.70 TIF 2000-09-21 43 Open Water 28.3
        2002-07-17 36 Open Water 21.3
        2006-07-04 37 Open Water 22.3
Rocknest Lake 9.00 18.10 TIF 2014-08-12 68.8 Open Water 50.7
        2015-08-06 79.5 Open Water 61.4
        2016-07-07 23.9 Open Water 5.8
Arsenic (μg/L)              
Daring Lake - - - - - - -
Desteffany Lake 0.20 0.45 TIF n/a n/a n/a n/a
Lac de Gras 0.20 0.20 TIF - - - -
Rocknest Lake 0.20 0.20 TIF - - - -
Barium (μg/L)              
Daring Lake 1.00 2.51 TIF 2004-03-19 3.9 Under Ice 1.39
        2006-07-26 3.5 Open Water 0.99
        2009-03-26 2.8 Under Ice 0.29
        2015-03-27 14 Under Ice 11.49
Desteffany Lake 1.10 2.70 TIF 2006-07-04 6.7 Open Water 4
        2008-03-31 2.8 Under Ice 0.1
        2018-03-13 3.5 Under Ice 0.8
Lac de Gras 1.00 2.95 TIF 2000-04-13 3 Under Ice 0.05
        2006-07-04 7.2 Open Water 4.25
        2008-07-28 3.3 Open Water 0.35
        2015-03-27 3.1 Under Ice 0.15
        2017-03-23 3.5 Under Ice 0.55
        2018-03-13 3.6 Under Ice 0.65
Rocknest Lake 2.20 4.35 TIF 2008-08-06 4.6 Open Water 0.25
        2015-09-03 4.5 Open Water 0.15
        2019-07-10 7.2 Open Water 2.85
        2019-08-08 5.1 Open Water 0.75
Copper (μg/L)              
Daring Lake 0.20 0.70 M2MAD 2003-05-01 2.1 Spring Freshet 1.3
        2004-03-19 2 Under Ice 1.2
        2004-05-19 1.9 Spring Freshet 1.1
        2008-07-07 1.1 Open Water 0.3
        2015-03-27 0.9 Under Ice 0.1
Desteffany Lake 0.20 1.41 TIF 2002-10-17 3.29 Open Water 1.88
        2004-02-03 1.65 Under Ice 0.24
        2004-05-19 2 Spring Freshet 0.59
        2006-03-22 5.5 Under Ice 4.09
        2006-07-04 3 Open Water 1.59
Lac de Gras 0.20 4.10 TIF 2006-03-22 5.2 Under Ice 1.1
Rocknest Lake 0.20 1.25 TIF 2009-03-26 1.9 Under Ice 0.65
Lithium (μg/L)              
Daring Lake 0.31 1.61 TIF 2006-07-26 0.2 Open Water -0.1
        2008-07-07 3.3 Open Water 1.39
        2015-03-27 4.6 Under Ice 2.99
Desteffany Lake 0.60 2.26 TIF 2008-07-07 4.5 Open Water 2.24
Lac de Gras 0.50 2.70 TIF - - - -
Rocknest Lake 0.50 1.30 TIF 2007-08-17 0.4 Open Water -0.1
        2007-09-13 0.4 Open Water -0.1
        2008-07-07 3 Open Water 1.7
Mercury (μg/L)              
Daring Lake - - - - - - -
Desteffany Lake - - - - - - -
Lac de Gras - - - - - - -
Rocknest Lake - - - - - - -
Molybdenum (μg/L)              
Daring Lake - - - - - - -
Desteffany Lake 0.02 0.35 TIF 2006-07-04 1.2 Open Water 0.85
Lac de Gras 0.02 0.60 TIF 2002-07-17 3 Open Water 2.4
Rocknest Lake - - - - - - -
Nickel (μg/L)              
Daring Lake 0.10 0.45 TIF 2003-05-01 0.5 Spring Freshet 0.05
        2004-03-19 0.7 Under Ice 0.25
        2004-05-19 3.4 Spring Freshet 2.95
        2015-03-27 1.5 Under Ice 1.05
        2016-09-07 2.2 Open Water 1.75
Desteffany Lake 0.40 1.10 TIF n/a n/a n/a n/a
Lac de Gras 0.60 1.40 TIF 2000-04-13 2 Under Ice 0.6
        2002-08-28 2 Open Water 0.6
Rocknest Lake 0.40 1.00 TIF 2008-03-31 1.1 Under Ice 0.1
Strontium (μg/L)              
Daring Lake 3.80 10.14 TIF 2004-03-19 12.9 Under Ice 2.76
        2015-03-27 38.9 Under Ice 28.76
Desteffany Lake 1.19 14.69 TIF 2017-03-23 15.5 Under Ice 0.81
        2018-03-13 15.8 Under Ice 1.11
        2019-03-18 15.5 Under Ice 0.81
Lac de Gras 4.60 17.83 TIF 2017-03-23 18.1 Under Ice 0.27
        2018-03-13 19.3 Under Ice 1.47
        2019-03-18 18.3 Under Ice 0.47
Rocknest Lake 4.55 9.75 TIF 2007-08-17 4.5 Open Water -0.05
        2019-07-10 13.4 Open Water 3.65
        2019-08-08 10.4 Open Water 0.65
Uranium (μg/L)              
Daring Lake - - - - - - -
Desteffany Lake - - - - - - -
Lac de Gras - - - - - - -
Rocknest Lake - - - - - - -
               
n/a = no exceedances ‘-‘ = %<DL is too high to get an accurate count of exceedances              

Index