esrd - baseline water well testing report

BASELINE WATER WELL TESTING DATA ASSESSMENT

Submitted To:

Guy Bayegnak Groundwater Policy Branch Alberta Environment Prepared By: Don Jones Bernhard Mayer Cathy Main

March 31, 2011

BASELINE WATER WELL TESTING DATA ASSESSMENT i

ALBERTA INNOVATES TECHNOLOGY FUTURES MARCH 31, 2011

EXECUTIVE SUMMARY Alberta Environment (AENV) contracted Alberta Innovates Technology Futures (AITF) (formerly Alberta Research Council Inc.) to review and evaluate the data in the Baseline Water Well Testing (BWWT) database to determine trends in baseline conditions and any observable changes in water quality of wells that were tested more than once. The BWWT database includes data from across the province. The province-wide data provided within the BWWT was used for statistical analysis, however, GIS maps concentrated primarily on the area lying within township 01-046-W5 to township 17-020-W4 (31,250 km2 ) as this is the main area for CBM drilling. AENV provided AITF with a database of results upon which this study was based. Limitations within the database provided by AENV to AITF are primarily related to laboratory and sampling variability and data entry issues. The large number of parties involved in sampling, laboratory analysis and data entry has added an element of variability in laboratory detection limits, sampling methodologies and data representation. The study does not distinguish between geologically based influences on groundwater such as formation composition, bedrock lineament features, or buried ancient alluvial channels. It also does not identify which water quality characteristics may be a result from impacts due to anthropogenic activities such as agricultural practices (e.g. fertilizers, bacteriological impacts) or oil and gas activities. Trends in major ions identified in water collected from wells located within the study area can be generally divided into areas with linear type trends and cluster areas. North-south oriented bands of wells with a similar concentration of a particular parameter were found to generally align with the formation region subcrops. These north-south bands were observed with total alkalinity and bicarbonate. Lower concentrations of alkalinity and bicarbonate were found in the west and higher concentrations were found to the east. In contrast, fluoride has the greatest amount of wells with elevated ion concentrations in the west as opposed to the east. The trend in fluoride is important since over 40% of wells completed at a depth greater than 60 mbgs exceed the Canadian Drinking Water Guidelines (2010). Areas of high and low ion concentrations have been identified as part of the study. An area of elevated ion concentrations associated with a northeast linear trend located approximately between Airdrie to Three Hills/Stettler (in some instances extending east to Drumheller) has been identified. This northeast trend has been observed in the following elevated ion distributions: calcium, magnesium, nitrate, potassium, sodium, sulphate, total alkalinity and TDS. Often clusters of high concentration wells are observed east of Calgary in the Strathmore area. Areas of low ion concentrations are also noted in the Calgary area for bicarbonate, carbonate and calcium ions as well as alkalinity. Concentrations of the ions in the samples versus depth range of each well were examined. The median concentrations of calcium, potassium and sulphate as well as TDS were found to decrease with depth. However, carbonate, chloride and fluoride were found to increase with depth. The maximum values were observed for bicarbonate, manganese, magnesium, nitrate, nitrate + nitrite, potassium and total alkalinity at wells completed at depths of 30 mbgs or less.

BASELINE WATER WELL TESTING DATA ASSESSMENT ii

Other ions such as chloride, fluoride, sodium, calcium, and TDS had maximum values in samples collected from wells completed between 60 to 100 mbgs. It is expected that strong trends in concentration of ion versus depth may be related to differences in geology between formations. The Canadian Drinking Water Guidelines (2010) were exceeded at most locations for aesthetic objectives for TDS and sodium, and the maximum acceptable concentration (MAC) for fluoride was exceeded at approximately 25% of the wells. Water samples exceeding chloride aesthetic objectives and fluoride MAC objectives were greatest with wells completed at depth. Water samples exceeding iron and sulphate aesthetic objectives and nitrate MAC objectives were greatest in the shallow wells. The wells with bacteriological impacts are generally randomly distributed but highly prevalent within the study area especially in the Edmonton to Calgary corridor. It appears that the area bounded by Airdrie, Stettler, Hanna and Red Deer has a high concentration of wells with bacteriological detection. Although approximately half of the wells in which bacteria were detected did not have completion information, the highest number of wells impacted by bacteria that did have completion data was completed from 30 to 60 mbgs (with the exception of E. coliform where 58% of the wells impacted did not have completion information). The data within the AENV database indicate that 53 wells were impacted (i.e. tested positive) by E. coli coliform, 387 wells were impacted by fecal coliform, 2,990 wells were impacted by total coliform, 4,797 wells were impacted by SRB and 8,407 wells tested positive for IRB within the study area. There are more shallow wells (i.e. 0 to 60 mbgs) than deep wells in the study area and most of these wells are impacted by some form of bacteria. The database achieves its objective of generating a baseline of concentrations and 13C values of methane in free gas of shallow groundwater. For 636 free gas samples passing the data quality criteria a median methane concentration of 436,085 ppm was observed. The highest methane concentrations occurred in the deepest wells (>100 mbgs). The median ethane concentration in 267 free gas samples passing the data quality criteria was 1,200 ppm with the highest ethane concentrations occurring in wells completed in 60 to 100 mbgs. There were 58 wells for which propane concentrations in free gas were reported. For 396 samples for which data quality criteria were met the median 13C value of methane was -67.2 . In free gas obtained from wells completed in 100 mbgs methane had a slightly higher median 13C value of -65.0 . The median 13C value of ethane in 300 free gas samples was -48.0 with no significant depth dependence. The median 13C value of propane for 16 samples meeting the data quality criteria was -33.7 . The majority of the free gas samples contained predominantly methane and some ethane, had wetness parameters >1000 and 13C values of methane typically below -60 , indicating biogenic gas formation processes. The accumulated information in the database will be in many cases of great value to trace potential future impacts on free gas in shallow groundwater provided that the chemical and isotopic composition of coal gases and deeper formation gases are known and isotopically distinct (e.g. Tilley & Muehlenbachs, 2006). During re-sampling of wells it is highly desirable to use similar sampling procedures to assure comparability of results.

BASELINE WATER WELL TESTING DATA ASSESSMENT iii

Also, the analytical accuracy of participating laboratories for concentration data reported near the detection limits and 13C values for low concentration gas samples should be further evaluated. Based on the results of this study, recommendations are summarized below.

Gas sample results require that data from all gases be entered so that the total gas concentrations sum to ppm.

Data be entered into the database be standardized into a singular measurement unit where possible (e.g. conductivity, major ions, well completion depth information) so that comparisons to data can be made more readily without having to check and revise the database.

Well water sample results should be tied to a unique well identification number (GIC number) rather than a location number so that retest data for the wells can more easily be compared. It would be helpful if this well identifier was placed on the individual wells in the field to reduce the potential for monitoring well identification errors in the field.

Well completion data should include screen depth so that water chemistry can be linked to formations.

It would be beneficial if data could be pre-screened prior to entry into the database so that discrepancies or concerns regarding data entry error could be addressed in a proactive manner.

Additional value would be provided by considering temporal variability in the near-surface aquifer water quality data results.

The accuracy of gas concentration data below 100 ppm for methane, ethane, propane and butane should be checked.

BASELINE WATER WELL TESTING DATA ASSESSMENT iv


Table of Contents EXECUTIVE SUMMARY ............................................................................................................... i

1. INTRODUCTION ............................................................................................................... 1 1.1 Background ...................................................................................................... 1

2. PROJECT SCOPE ............................................................................................................ 3

3. METHODOLOGY .............................................................................................................. 3 3.1 Data Extraction and QA/QC Assessment ....................................................... 3 3.2 Data Assessment and Analyses ..................................................................... 5 3.3 Study Limitations and Assumptions .............................................................. 5 3.3.1 Limitations with Existing Database ..................................................................... 5 3.3.2 Assumptions and Limitations of the Study .......................................................... 6

4. DATA EVALUATION RESULTS ...................................................................................... 7 4.1 Major Ion Characteristics ................................................................................ 7 4.2 Major Ion Frequency and Spatial Distribution ............................................... 8 4.2.1 Bicarbonate ........................................................................................................ 8 4.2.2 Carbonate ........................................................................................................... 9 4.2.3 Calcium ............................................................................................................. 10 4.2.4 Chloride ............................................................................................................ 12 4.2.5 Fluoride ............................................................................................................. 13 4.2.6 Dissolved Iron ................................................................................................... 15 4.2.7 Manganese ....................................................................................................... 16 4.2.8 Magnesium ....................................................................................................... 17 4.2.9 Nitrate + Nitrite ................................................................................................. 18 4.2.10 Nitrite ................................................................................................................ 20 4.2.11 Nitrate - Nitrogen .............................................................................................. 21 4.2.12 Potassium ......................................................................................................... 22 4.2.13 Sulphate ........................................................................................................... 24 4.2.14 Sodium ............................................................................................................. 25 4.2.15 Total Alkalinity .................................................................................................. 27 4.2.16 Total Dissolved Solids (TDS) ............................................................................ 29 4.2.17 Frequency and Spatial Distribution Summary .................................................. 30 4.3 Bacteriological Characteristics: Frequency and Spatial Distribution ....... 31 4.3.1 Bacteriological Data Concentrations ................................................................ 32 4.3.1.1 E. coli Coliform ................................................................................................. 32 4.3.1.2 Fecal Coliform .................................................................................................. 33 4.3.1.3 Total Coliform ................................................................................................... 35 4.3.1.4 Sulphur Reducing Bacteria (SRB) .................................................................... 36 4.3.1.5 Iron Related Bacteria (IRB) .............................................................................. 38 4.3.2 Summary of Bacteriological Characteristics: Frequency and Spatial

Distribution ........................................................................................................ 39 4.4 Gas Characteristics ........................................................................................ 39 4.4.1 Gas Concentrations .......................................................................................... 41 4.4.1.1 Methane ............................................................................................................ 41 4.4.1.2 Ethane .............................................................................................................. 43

BASELINE WATER WELL TESTING DATA ASSESSMENT v


4.4.1.3 Propane ............................................................................................................ 44 4.4.1.4 Butane and Iso-Butane ..................................................................................... 46 4.4.1.5 Carbon Dioxide ................................................................................................. 48 4.4.1.6 Non-Standard Parameters ................................................................................ 50 4.4.2 Carbon Isotope Ratios ...................................................................................... 51 4.4.2.1 Methane ............................................................................................................ 51 4.4.2.2 Ethane .............................................................................................................. 53 4.4.2.3 Propane ............................................................................................................ 55 4.4.2.4 Butane and Iso-Butane ..................................................................................... 55 4.4.2.5 Carbon Dioxide ................................................................................................. 55 4.4.3 Origin of Methane ............................................................................................. 57 4.5 Repeat Tests ................................................................................................... 60 4.5.1 Major Ions ......................................................................................................... 60 4.5.1.1 Bicarbonate ...................................................................................................... 60 4.5.1.2 Calcium ............................................................................................................. 61 4.5.1.3 Carbonate ......................................................................................................... 62 4.5.1.4 Chloride ............................................................................................................ 62 4.5.1.5 Conductivity ...................................................................................................... 63 4.5.1.6 Fluoride ............................................................................................................. 63 4.5.1.7 Dissolved Iron ................................................................................................... 64 4.5.1.8 Magnesium ....................................................................................................... 64 4.5.1.9 Manganese ....................................................................................................... 65 4.5.1.10 Nitrate + Nitrite ................................................................................................. 66 4.5.1.11 Nitrate ............................................................................................................... 66 4.5.1.12 Nitrite ................................................................................................................ 67 4.5.1.13 pH ..................................................................................................................... 67 4.5.1.14 Potassium ......................................................................................................... 68 4.5.1.15 Sodium ............................................................................................................. 68 4.5.1.16 Sulphate ........................................................................................................... 69 4.5.1.17 Total Dissolved Solids ...................................................................................... 69 4.5.1.18 Total Alkalinity .................................................................................................. 70 4.5.2 Gas Concentration and Isotope Repeat Tests ................................................. 71 4.5.2.1 Free gas retest ................................................................................................. 71 4.5.3 Changes in Concentrations and Carbon Isotope Ratios of Gas Samples ........ 72 4.5.3.1 Concentrations and Carbon Isotope Ratios of Methane ................................... 72 4.5.3.2 Concentrations and Carbon Isotope Ratios of Ethane ..................................... 73 4.5.3.3 Concentrations and Carbon Isotope Ratios of CO2 .......................................... 73

5. CONCLUSIONS .............................................................................................................. 74 5.1 Database Limitations ..................................................................................... 74 5.2 Major Ion Trends ............................................................................................ 75 5.3 Bacteria ........................................................................................................... 76 5.4 Gas Concentrations and Isotope Ratios ...................................................... 76 5.5 Retest Data ...................................................................................................... 77

6. RECOMMENATIONS ..................................................................................................... 77

REFERENCES ........................................................................................................................... 79

BASELINE WATER WELL TESTING DATA ASSESSMENT vi


List of Tables Table 1: Major Ion Ranges (Mg/L) In Shallow Groundwater From Formations Of

Interest. .................................................................................................................... 2 Table 2: Water Chemistry Ranges Summarized From Regional Groundwater Studies ........ 3 Table 3: Considered Parameters And Corresponding Drinking/ Livestock/Irrigation

Water Guidelines. ..................................................................................................... 7 Table 4: Number Of Samples For Which Groundwater Concentrations Exceeded The

Detection Limit Of The Listed Compounds. ............................................................ 50 Table 5: Summary Of Chemical And Isotopic Parameters For Free Gas Samples For

Which Propane Concentrations Were Reported. ................................................... 59 Table 6: Ranges Of Retest Data Trends For Major Ions. ..................................................... 60 List of Figures Figure 1. Summary of Bicarbonate Statistics .......................................................................... 8 Figure 2. Summary of Carbonate Statistics ............................................................................. 9 Figure 3. Summary of Calcium Statistics ............................................................................... 11 Figure 4. Summary of Chloride Statistics .............................................................................. 12 Figure 5. Summary of Fluoride Statistics ............................................................................... 14 Figure 6. Summary of Dissolved Iron Statistics ..................................................................... 15 Figure 7. Summary of Manganese Statistics ......................................................................... 16 Figure 8. Summary of Magnesium Statistics ......................................................................... 17 Figure 9. Summary of Nitrate + Nitrite Statistics .................................................................... 19 Figure 10. Summary of Nitrite Statistics .................................................................................. 20 Figure 11. Summary of Nitrate-N Statistics ............................................................................. 21 Figure 12. Summary of Potassium Statistics ........................................................................... 23 Figure 13. Summary of Sulphate Statistics ............................................................................. 24 Figure 14. Summary of Sodium Statistics ............................................................................... 26 Figure 15. Summary of Total Alkalinity Statistics .................................................................... 28 Figure 16. Summary of Total Dissolved Solids Statistics ........................................................ 29 Figure 17. Summary of E. coli Statistics .................................................................................. 32 Figure 18. Summary of Fecal Coliform Statistics .................................................................... 34 Figure 19. Summary of Total Coliform Statistics ..................................................................... 35 Figure 20. Summary of Sulphur Reducing Bacteria Statistics ................................................. 37 Figure 21. Summary of Iron Related Bacteria Statistics .......................................................... 38 Figure 22. Summary of Methane Concentration Statistics ...................................................... 42 Figure 23. Summary of Ethane Concentration Statistics ......................................................... 43 Figure 24. Summary of Propane Concentration Statistics ....................................................... 45 Figure 25. Summary of Iso-Butane Concentration Statistics ................................................... 47 Figure 26. Summary of Carbon Dioxide Concentration Statistics ........................................... 49 Figure 27. Summary of Methane Isotope Statistics ................................................................. 52 Figure 28. Summary of Ethane Isotope Statistics ................................................................... 54 Figure 29. Summary of Carbon Dioxide Isotope Statistics ...................................................... 56

BASELINE WATER WELL TESTING DATA ASSESSMENT vii


Appendices / List of Figures Appendix A Figures 4111.1 to 4111.7 Bicarbonate Concentration Figures 4112.1 to 4112.7 Carbonate Concentration Figures 4113.1 to 4113.7 Calcium Concentration Figures 4114.1 to 4114.7 Chloride Concentration Figures 4115.1 to 4115.7 Fluoride Concentration Figures 4116.1 to 4116.7 Dissolved Iron Concentration Figures 4117.1 to 4117.7 Manganese Concentration Figures 4118.1 to 4118.7 Magnesium Concentration Figures 4119.1 to 4119.7 Nitrate + Nitrite Figures 41110.1 to 41110.7 Nitrite Concentration Figures 41111.1 to 41111.7 Nitrate Concentration Figures 41112.1 to 41112.7 Potassium Concentration Figures 41113.1 to 41113.7 Sulfate Concentration Figures 41114.1 to 41114.7 Sodium Concentration Figures 41115.1 to 41115.7 Total Alkalinity Concentration Figures 41116.1 to 41116.7 TDS Concentration Appendix B Figures 4211.1 to 4211.7 E. coli Counts Figures 4212.1 to 4212.8 Fecal Coliform Counts Figures 4213.1 to 4213.8 Total Coliform Counts Figures 4214.1 to 4214.7 SRB Counts Figures 4215.1 to 4215.8 IRB Counts Appendix C Figures 4311.1 to 4311.7 Methane Concentration Figures 4312.1 to 4312.7 Ethane Concentration Figures 4313.1 to 4313.7 Propane Concentration Figures 4314.1 to 4314.2 Butane Concentration Figures 4315.1 to 4315.7 Carbon Dioxide Concentration Figures 4316.1 to 4316.7 Iso-Butane Concentration Figures 4321.1 to 4321.7 Methane Gas 13C/12C Ratio Figures 4322.1 to 4322.7 Ethane Gas 13C/12C Ratio Figures 4323.1 to 4323.7 Propane Gas 13C/12C Ratio Figures 4324.1 to 4324.2 Iso-Butane Gas 13C/12C Ratio Figures 4325.1 to 4325.7 Carbon Dioxide 13C/12C Ratio Gas Figure 4410.1 Change in Gas Production Figure 4421.1 Methane PPM Change for Retests Figure 4421.2 Methane 13C Change (in )from Retests Figure 4422.1 Ethane PPM Change for Retests Figure 4422.2 Ethane 13C Change (in ) from Retests Figure 4423.1 Carbon Dioxide PPM Change for Retests Figure 4423.2 Carbon Dioxide 13C Change (in ) from Retests

BASELINE WATER WELL TESTING DATA ASSESSMENT viii


Appendix D Figures 4411.1 to 4411.2 Bicarbonate Change Figures 4412.1 to 4412.2 Calcium Change Figures 4413.1 to 4413.2 Carbonate Change Figures 4414.1 to 4414.2 Chloride Change Figures 4415.1 to 4415.2 Conductivity Change Figures 4416.1 to 4416.2 Fluoride Change Figures 4417.1 to 4417.2 Dissolved Iron Change Figures 4418.1 to 4418.2 Magnesium Change Figures 4419.1 to 4419.2 Manganese Change Figures 4420.1 to 4420.2 Total Iron Change Figures 44110.1 to 44110.2 Nitrate + Nitrite Change Figures 44111.1 to 44111.2 Nitrate Change Figures 44112.1 to 44112.2 Nitrite Change Figures 44113.1 to 44113.1 pH Change Figures 44114.1 to 44114.2 Potassium Change Figures 44115.1 to 44115.2 Sodium Change Figures 44116.1 to 44116.2 Sulphate Change Figures 44117.1 to 44117.2 TDS Change Figures 44118.1 to 44118.2 Total Alkalinity Change

BASELINE WATER WELL TESTING DATA ASSESSMENT 1


1. INTRODUCTION 1.1 Background Alberta Environment (AENV) obtained Alberta Innovates Technology Futures (AITF) (formerly Alberta Research Council Inc.) to review and evaluate the data in the Baseline Water Well Testing (BWWT) database to determine trends in baseline conditions and any observable changes in water quality of wells that were tested more than once. The BWWT database includes data from across the province. The province-wide data provided within the BWWT was used for statistical analysis, however, GIS maps concentrated primarily in the area lying within township 01-046-W5 to township 17-020-W4 (31,250 km2) as this is the main area for CBM drilling. AENV provided AITF with a database of results upon which this study was based. Baseline Water Well Testing Requirements for Coalbed Methane Wells Completed Above the Base of Groundwater Protection, also known as the (BWWT) Environmental Resources Conservation Board (ERCB) Directive 35, came into effect in May 2006. The directive involves the assessment of certain water quality parameters within a 600-800m radius of potential CBM drilling projects to establish a baseline against which future water quality may be compared. The Baseline Water Well Testing Standard (BWWTS) was developed by Alberta Environment in 2006, in response to the Multi-Stakeholder Advisory Committee (MAC) recommendations. BWWT has now been in operation for four years. To date, approximately 11,000 tests have been performed and reside in the BWWT database. The majority of the groundwater wells considered in this study was completed in central Alberta, deriving their water resources from Quaternary, Tertiary, and Upper Cretaceous formations. The Belly-River, Edmonton, and Paskapoo clastic wedges are the deposits of interest for this study and are comprised of dominantly fluvial and non-marine siliciclastics (Cheung et al., 2010). The corresponding aquifers of interest are the Scollard-Paskapoo, Horseshoe Canyon, and Belly River aquifers. The hydrogeochemistry of each aquifer is partially controlled by the mineralogic composition of the surrounding bedrock (see Figure 29 from Bachu and Michael (2002) for a cross sectional view of the flow system in the Upper Cretaceous-Tertiary bedrock). General groundwater chemistry ranges for waters in these systems are summarized in Table 1. The large ranges observed for some parameters (see Table 1), particularly for chloride and sodium, illustrate the variability of groundwater chemistry associated with samples from variable depths and large spatial distributions. As such, outlying or extreme values must be evaluated with caution when assessing water quality of a large region such as the area of interest for this study.



TABLE 1: MAJOR ION RANGES (MG/L) IN SHALLOW GROUNDWATER FROM FORMATIONS OF INTEREST.

Formation Parameter Maximum Minimum

Scollard- Paskapoo

bicarbonate 4000 54

calcium 198 0.8

chloride 16953 0.5

iron 0.04*



TABLE 2: WATER CHEMISTRY RANGES SUMMARIZED FROM REGIONAL GROUNDWATER STUDIES

Parameter Maximum Minimum Median alkalinity 3472 11 519.5 chloride 4135 0 7.9 fluoride 388 0 0.6 nitrate + nitrite 748 0 0.4 sodium 31510 0 259.8 sulphate 6495 0 311.15 TDS 11868 0 912.6

Modified from HCL reports (2001, 2002, 2003, 2005) and Stantec, 2005.

2. PROJECT SCOPE The purpose of the study was to determine if data supplied to AITF from the AENV BWWT database show evidence of spatial trends in water quality and any temporal trends if sufficient well repeat tests are available in the database. The study scope included the following: The extraction and manipulation of spreadsheet data provided by Alberta Environment

from the BWWT database to allow for statistical analyses and use in the production of distribution maps;

Evaluation of major ion, bacteriological, and gas concentration and isotope data collected as part of the BWWT.

o Assessment of spatial distribution of total and depth delineated data using GIS

mapping. o Univariate statistical analysis for each water quality parameter. o Assessment of the number and distribution of wells with a water sample parameter

exceeding the Canadian Drinking Water Guidelines (Health Canada, 2010). Where carbon isotope data were available, the results are discussed in the context of the environmental conditions that are conducive to methane gas formation. Repeat tests are evaluated to assess any changes that may have occurred between baseline sampling events and retesting of water wells. Measured parameters in retested wells have been evaluated and mapped to ascertain whether or not changes can be correlated to spatial distributions.

3. METHODOLOGY 3.1 Data Extraction and QA/QC Assessment The data present in the BWWT database was subjected to QA/QC procedures prior to its use. The data was consolidated into a format that could be assessed for accuracy and completeness, used for statistical analysis and uploaded into a geographic information system. These procedures included:



Database queries to identify and allow the removal of duplicate entries in the database. Database queries to recognize different measurement units for parameters within the

database and allow for standardization of the data representation within the database. The queries were limited to determining completion depth discrepancies (ft. versus meters) and ion balance (90% to 110%) versus charge balance (0.9 to 1.1) entries within the database. Alberta Environment provided the database to AITF with the understanding that the database had a QA/QC check completed.

Data queries to identify the different detection limits used in different laboratories for the parameters within the database and development of a standard method of representation.

Data queries to allow the water quality results to be linked graphically to a spatial location on a map as well as to well completion depths where available.

The bedrock geology subcrops were mapped for the study area and well locations included in this study were overlaid on the subcrop map. Data quality results were graphically displayed by well and depth ranges using the subcrop map as base map.

Data sets were screened for accuracy by using ion balance criteria of 90 110 % or 0.9 to 1.1 to isolate analyses of value and exclude those with potential erroneous data sets. The results from the sampling suites that did not meet the QA/QC procedure for ion balance were excluded from the study. The well water quality results of the study were linked to the completion depth of the wells where available. The concentration data that met the selection criteria were then merged with the well and location data. Well depth data provided within the database was supplemented by data from the Alberta Environment groundwater information center (GIC) in instances where the well depth data was not present within the database and the GIC number of the well was available. Wells were divided into 4 depth-based groups (i.e. 0 to 30 meters below ground surface (mbgs), 30 to 60 mbgs, 60 to 100 mbgs and greater than 100 mbgs) so that changes in water chemistry versus depth could be assessed. These depth ranges are based on Alberta Environments groundwater observation well network depth ranges for shallow, intermediate and deep wells 0 to 30, 30 to 100 and over 100 meters, respectively. The additional split at 60 meters was done to decrease the number of wells in a single group for mapping. Of the 8,407 records that satisfy the ion balance criteria, 36% of the wells have a depth between 0.1 to 30 mbgs. 28% of the wells have a depth between 30-60 mbgs, 12% have a depth of 60-100 mbgs, and 3% have a depth greater than 100 mbgs. A total of 21% of the data have no records related to depth of well. Insufficient information was available within the database to determine the formation over which the well was screened. However, the well location data was overlaid on a map of the bedrock formation subcrops located within the study area. The associated geological formations were obtained from the Alberta Geological Survey (AGS, digital dataset 2004-0033). The files were loaded into ARCGIS 9.3.1 and presented graphically by chemical parameter and depth of well.



3.2 Data Assessment and Analyses Univariate summary statistics provide a simple way of describing the distribution of the dataset and are often useful when managing high volumes of data. The median (M), and mode of the data indicate how the centre of the data is distributed across the upper (max) and lower (min) ranges of the dataset. The inter-quartile ranges (Q1 and Q3) describe the variability of the data set and are useful indicators of how the data is spread, especially when erratically high values are present in the data set. Such tests are important as they not only provide an assessment of the data quality, but also can highlight simple input errors that may be easily remedied. Data was plotted with the use of whisker plots to show median values, data distribution (first, second and third quartile) and maximum and minimum range in values. 3.3 Study Limitations and Assumptions 3.3.1 Limitations with Existing Database Limitations with the existing database are primarily related to laboratory and sampling variability and data entry issues. Data in the database has come from water sampling studies and reports conducted by approximately 35 consulting companies for the BWWT parameters. The major ion parameters have been analyzed in 14 different laboratories using various analytical methods and with different minimum detection limits (MDL). The gas isotope analyses were conducted in at least 3 different laboratories. The general gas concentration analyses were conducted in 10 laboratories with MDLs ranging from 1 to 300 ppm for methane alone. A total of 15 different laboratories analyzed the bacterial samples using at least 5 different units for measuring the number of bacteria in the water samples. These issues increase variability, complexity and uncertainty in evaluating trends in concentration over different depth ranges and/or geographic locations and in assessing retested well samples. Analytical laboratory results are entered into the BWWT database by consultants using a spreadsheet loader. The data entered in the database for a specific sample include the sample number (which links all of the samples and the well information together), the name of the laboratory that analyzed the sample, the operator for the results (e.g. less than or trace), the result(s) of the analysis, the units or in the case of gas concentration of the sample parameter, a QC value to confirm that the results that have been checked against the lab result sheet, and a QC comment which identifies any changes made to the data. Some of the issues that were found with the BWWT database during our work with the data include: 1. Depth and well competition intervals that have no units or contradictory units.

2. Ion balance appears to be either a mix of ion balance and charge balance or units are incorrect for some of the data.

3. From the data that AITF received it is not easy to tell if gas was present during sampling of the well.



4. There is no way to tell if gas concentrations have been corrected for atmospheric influences or if the oxygen results have not been entered.

5. It is not possible to tell if the gas concentration data has been normalized or is raw data.

6. The addition of a total ppm for gas concentration would allow a simple check of input gas concentrations.

7. Samples for free gas are not always completely entered in the database for all parameters analyzed. For the purposes of this study, such samples were removed from our analysis as they did not meet the studys initial screening criteria (detailed in Section 4.4).

8. There are sample IDs that have isotope analysis results but do not have gas concentration results. The quality of the isotopic data without gas concentration results is difficult to assess.

9. Results of data that are not parameters required as part of the BWWT sampling suite are included in the database. It should be determined whether these results, although small in number, should be part of the database.

10. There is no way to assess the reason for missing results in the database. There is only a blank for the parameter but one cannot be sure as to the reason for the lack of data.

11. There should be an effort to identify the wells that have been retested. The use of a GIC number in the database or some other identification would clearly identify wells that have been retested. Presently data that represent a retested well can only be identified by well location.

3.3.2 Assumptions and Limitations of the Study In an effort to allow the data within the database to be compared and studied for potential trends, specific assumptions were made. The assumptions included within this study are as follows: Alberta Environment conducted QA/QC checks on the data within the database. As such, it

is not within the scope of this study for AITF to conduct such checks on the data held within the database. The study was undertaken based on the understanding that AITF should proceed using the data provided to them in the form, in which it has been provided by Alberta Environment.

Blanks within the database are assumed to indicate that no data is available rather than an indication of non-detect.

Some of the well locations are referenced to the center of the section (or at times quarter section) within which they are found. As such, when wells are graphically displayed on a landscape scale, the wells within each section are overlapped on the maps. This is an issue where symbols with colours are used to indicate the degree of impact. The symbols used have been given different sizes with the highest concentration values being represented by the largest coloured circles. It is anticipated, however, that not every well water quality result will be visually apparent on the maps. Therefore, the maps should only be relied on to determine regional, qualitative assessments of trends rather than to determine the exact location of all wells with elevated concentrations of a given parameter.



4. DATA EVALUATION RESULTS 4.1 Major Ion Characteristics The major ions were evaluated based on the concentrations of parameters based on depth using univariate statistics. Univariate summary statistics were calculated for each of the parameters tested to derive a general understanding of the distribution of data in both concentration and frequency. The statistical analyses were conducted on the samples that met the QA/QC requirements of the study (i.e. ion balance within 10% of 100%). In addition, non-detects were included in the data analyses to allow an understanding distribution with depth and frequency. As different method detection limits (MDL) were used by different laboratories, the MDLs were standardized per parameter for the purposes of the statistical analyses. The assumed value was the lowest (i.e. AITF laboratories in Vegreville, Alberta) for each parameter and these assumed values are noted at the bottom of each statistical results table in Appendix A. Tables for summary statistics for each parameter and the corresponding frequency distribution histograms are also presented in Appendix A. Major ion concentrations were compared to Canadian Drinking Water Guidelines (Health Canada, 2010) in Table 3. Parameters, notably fluoride and nitrate, are of concern for drinking water safety (Table 3). The well water chemistry results were overlaid on the formation subcrop map (Appendix A) to allow for reference and comparison. The subcrop map illustrates where the geological formations subcrop and does not indicate that all wells falling within the area of the subcrop are actually screened within that particular formation. In this regard, the report will refer to the subcrop areas as subcrop regions rather than formations. TABLE 3: CONSIDERED PARAMETERS AND CORRESPONDING DRINKING/ LIVESTOCK/IRRIGATION WATER GUIDELINES.

Parameter Unit Potable Drinking

Water

MAC AO Livestock Irrigation Bicarbonate mg/L Calcium mg/L 1000 Carbonate mg/L Chloride mg/L 250 100-700 Fluoride mg/L 1.5 1 - 2 1 Iron mg/L 0.3 5 Magnesium mg/L Manganese mg/L 0.05 0.2 Nitrite mg/L 10 Nitrate - Nitrogen mg/L 10 Nitrite+Nitrate mg/L 100 Potassium mg/L Sodium mg/L 200 Sulphate mg/L 500 1000 Total Alkalinity mg/L TDS mg/L 500 500-3500

MAC - Maximum acceptable concentration from the Guidelines for Canadian Drinking Water Quality (Health Canada, 2010)

AO - Aesthetic Objectives from the Guidelines for Canadian Drinking Water Quality - Livestock and Irrigation Water Surface Water Quality Guidelines for uses in Alberta (Health Canada, 2010)



4.2 Major Ion Frequency and Spatial Distribution 4.2.1 Bicarbonate Of the 8,407 records that meet the criteria, 24 analyses were below detection limits (0.1 mg/L) Figure 4111.1, Appendix A). The median value for all data is 584 mg/L. Median values were calculated for data from the four depth ranges with 555 mg/L as the lower median value (at > 100 mbgs) and 598 mg/L as the upper median value (30-60 mbgs). A total of 25% of all the data showed concentrations below 459 mg/L and 75% of the data indicated concentrations below 712 mg/L. The data fall within ranges for the shallow formation waters identified within previous studies (Table 1). Figure 1 below summarizes the median, 25% and 75% percentile and maximum for all depth ranges. All summary statistics for bicarbonate can be seen in section 4111.1 in Appendix A.

Bicarbonate

0

500

1000

1500

2000

2500

3000

3500

0.1-30 mbgs 30.01-60 mbgs 60.01-100mbgs >100mbgs IB 90-110%

Conc

entr

atio

n (m

g/L)

Max

Min Q1

Q3 Median

Figure 1. Summary of Bicarbonate Statistics The spatial distribution of bicarbonate concentrations in the BWWT database was plotted to ascertain any spatial trends. Figure 4111.2 shows all bicarbonate results for all wells sampled in the BWWT. The bicarbonate concentration increases from west to east with the higher concentrations, 827 to 3330 mg/L, occurring along the eastern edge of the upper Paskapoo into the lower Paskapoo and Scollard regions. These higher concentrations are most noticeable in the Stettler to Strathmore area. On the western edge of the sampling area bicarbonate concentrations are lower (up to 435 mg/L) in the southern area near Calgary and increase north of Airdrie ranging between 436 and 826 mg/L. Wells with a total depth of less than 30 mbgs, show a similar distribution to the total bicarbonate map. Wells along the western edge of the sampling area have a maximum bicarbonate concentration of 619 mg/L in the south and up to 826 mg/L north of Airdrie. The higher concentrations are found along the eastern edge of the upper Paskapoo and Scollard



regions and a small area east of Calgary in the Horseshoe Canyon region where bicarbonate concentrations can reach 1500 mg/L (Figure 4111.3). Wells with a depth of 30 to 60 mbgs show a similar distribution as displayed in Figures 4111.2 and Figure 4.111.3. The higher concentrations of bicarbonate (827 to 2670 mg/L) are found along the eastern edge of the upper Paskapoo region and also extend farther west in the region between Drumheller and Red Deer. An area of low bicarbonate concentrations (435 mg/L or less) located east of Calgary appears to extend over the upper Paskapoo and Scollard subcrop regions (Figure 4111.4) Figure 4111.5 to Figure 4.111.7 are spatial distributions maps for concentrations of bicarbonate for samples collected from wells with a total depth of 60 to 100 mbgs, >100 mbgs, and wells with no completion details. All three Figures show similar spatial distributions compared to those shown in Figures 4.111.1 through Figure 4.111.4 . 4.2.2 Carbonate Of the 8,339 records that meet the criteria, 3,373 analyses were below detection limits (0.1 mg/L) with the greatest median concentrations in wells with depths exceeding 100 mbgs (20.5 mg/L) (Figure 4112.1, Appendix A). The median value for all data is 9.3 mg/L with 0.10 mg/L as the lower value of the four depth ranges, while 671.0 mg/L was the maximum value. A total of 25% of all the data lies below 0.10 mg/L and 75% of the data lies below 21.0 mg/L. Figure 2 summarizes the median, 25% and 75% percentile and maximum for all depth ranges. The Figure illustrates that median carbonate concentrations increase with depth. All summary statistics for carbonate can be seen in section 4112.1, Appendix A.

Carbonate

0

5

10

15

20

25

30

35

40

45

50


Con

cent

ratio

n (m

g/L)

438 mg/L 671 mg/L 411 mg/L 103 mg/L

671 mg/L

Figure 2. Summary of Carbonate Statistics The spatial distribution of carbonate concentrations in the BWWT database was plotted to ascertain any spatial trends. Figure 4112.2 shows carbonate results for all wells sampled in the



BWWT. The carbonate concentrations of groundwater from wells sampled does not have a clear pattern but lower concentrations, 0 to 59 mg/L, occur in the area between Airdrie, Strathmore and the Bow River (i.e. south of Airdrie). The higher concentrations (60 to 671 mg/L) occur in an area between Drumheller to Red Deer and from Red Deer to Lacombe (i.e. north of Airdrie) from depths of 30 to 100 m (similar trend as bicarbonate). Wells with a total depth of less than 30 mbgs show a similar distribution as that shown in the carbonate map. Groundwater from wells in the area from the Bow River up through Strathmore to Three Hills has lower concentrations of carbonate (0-31 mg/L). The higher concentrations (60 to 113 mg/L) are found east of Three Hills, in the Red Deer area and around Stettler (Figure 4112.3). Carbonate concentrations for wells with a depth of 30 to 60 mbgs are shown in Figure 4112.4. The higher concentrations of 60 to 671 mg/L are scattered in the area from Airdrie to Drumheller and north to Wetaskiwin. The carbonate concentration is lower, 31 mg/L or less, in the area east of Calgary to Strathmore Figure 4112.5 is a spatial distributions map for the concentrations of carbonate over a depth of 60 to 100 mbgs. This map is very similar to the 30 to 60 mbgs distribution except that there are no wells with higher carbonate concentrations (i.e. greater at 60 mg/L) in the Stettler area and along the Red Deer River to Red Deer. Wells with a total depth of more than 100 mbgs are shown in Figure 4112.6. The higher carbonate concentration wells (32 to 103 mg/L) are located from Three Hills north to Red Deer. Wells with no depth data are mapped in Figure 4112.7. An area with groundwater having lower carbonate concentrations (i.e. 31 mg/L or less) is found south of Airdrie from Calgary to Strathmore. Higher carbonate concentration wells (32 to 438 mg/L) are generally found in an area from Three Hills to Hanna and north to Wetaskiwin and especially around the Stettler and Red Deer areas. 4.2.3 Calcium Of the 8,407 records that meet the criteria, 82 analyses were below detection limits (0.1 mg/L). All water well sample records had concentrations of calcium below the guidelines for livestock except for one well in the 60 to 100 mbgs range (i.e. 1000 mg/L). The median value for all data is 10.8 mg/L with 25% of all the data falling below 3.8 mg/L and 75% of the data falling below 46.3 mg/L. Figure 3 summarizes the median, 25% and 75%percentile and maximum Calcium concentrations for all depth ranges. The median concentration of calcium decreases with depth. Most calcium data is found within a range previously reported for water quality existing within formations associated with the study area (Table 1). All summary statistics for calcium can be seen in section 4113.1, Appendix A.



Figure 3. Summary of Calcium Statistics The spatial distribution of calcium concentrations in the BWWT database was plotted to ascertain any spatial trends. Figure 4113.2 shows calcium results for all wells sampled in the BWWT. The calcium concentration of groundwater from wells sampled does not have a clear pattern but lower concentrations, 0 to 95 mg/L, occur in the area between Airdrie, Strathmore and the Bow River. The higher concentrations (96 to 1000 mg/L) occur in an area between Airdrie, Drumheller and north to Innisfail and a second area immediately south of Wetaskiwin. Wells with a total depth of less than 30 mbgs show a similar distribution as that shown in the total calcium map. The higher concentrations (193 to 586 mg/L) are found in a linear area from Airdrie northeast to and beyond Three Hills and also in an area near Wetaskiwin (Figure 4113.3). Calcium concentrations for wells with a depth of 30 to 60 mbgs are shown in Figure 4113.4. The higher concentrations (i.e. 193 to 518 mg/L) are scattered in the area from Airdrie northeast to Three Hills. Only one well in the Wetaskiwin area had calcium concentrations in groundwater in the 193 to 518 mg/L range. Figure 4113.5 is a spatial distribution map for the concentrations of calcium over a depth of 60 to 100 mbgs. This depth range displayed a decrease in the frequency of higher calcium concentrations in wells. The majority of the wells are in the 0 to 35 mg/L range with a small number of wells having calcium concentrations between 36 to 192 mg/L in the area between Red Deer and Drumheller. The highest calcium concentrations in groundwater (193 to 1000 mg/L) were observed in wells at this depth range in the Airdrie area and northeast to the Hanna area. There is one well with groundwater having a calcium concentration of 2205 mg/L, which is above the livestock guidelines, just north east of Red Deer. This stands out as the next highest calcium concentration in groundwater from a well in the area is less than 192mg/L.

Calcium

0

10

20

30

40

50

60

70

80

90

100


Con

cent

ratio

n (m

g/L)

586 mg/L 518 mg/L 416 mg/L

2205 mg/L 2205 mg/L



Wells with a total depth of more than 100 mbgs are shown in Figure 4113.6. The higher calcium concentrations (i.e. 193 to 416 mg/L) were found in wells from Airdrie northeast to the Three Hills area. Most of the groundwater has calcium concentrations ranging from 0 to 35 mg/L. There are a small group of wells in the 36 to 192 mg/L range in the Buffalo Lake area. Wells with no depth data are mapped in Figure 4113.7. The calcium concentration spatial distribution is very similar to that described for the total wells sampled in Figure 4113.2 above. 4.2.4 Chloride A total of 127 analyses or 2% of all records within the database indicate chloride values that exceed aesthetic objectives for chloride concentration (250 mg/L) as specified in the Canadian Drinking Water Guidelines (2010). There are wells at all depth ranges which produced samples that are above the irrigation guidelines for chloride. The largest percentage of chloride samples that exceeded the objectives occurred in the deepest wells (>100mgbs); 17 of 214 samples exceeded aesthetic objectives for chloride at this depth. Of the 8,407 records, the median value for all data is 6.5 mg/L. A total of 25% of all the data lies below 2.5 mg/L and 75% of the data lies below 17.8 mg/L. All chloride data is found within a range previously reported for water quality existing within formations associated with the study area (Table 1, Table 3). Figure 4 summarizes the median, 25% and 75% percentile and maximum for all depth ranges. All summary statistics for chloride can be seen in section 4114.1, Appendix A.

Chloride

0

10

20

30

40

50

60

70

80

90

100


Con

cent

ratio

n (m

g/L)

1180 mg/L 1460 mg/L 2050 mg/L 2050 mg/L

990 mg/L

Figure 4. Summary of Chloride Statistics The spatial distribution of chloride concentrations in the BWWT database was plotted to ascertain any spatial trends. Figure 4114.2 shows chloride results for all wells sampled in the BWWT. Wells sampled between Airdrie and Lacombe generally have lower chloride concentrations on the west side of the sampling area while higher concentrations occur on the eastern edge over the Scollard region. The higher concentrations (251 to 2,050 mg/L) occur in an



area from Calgary to Strathmore and Airdrie to Three Hills and in a line running east west just south of Wetaskiwin. There are also a number of wells in the northern part of the Willow Creek region that have elevated chloride concentrations some of which reach up to 400 mg/L. Wells with a total depth of less than 30 mbgs show mostly low concentrations of chloride (040 mg/L) (Figure 4114.3). Chloride concentrations for wells with a depth of 30 to 60 mbgs are shown in Figure 4114.4. The higher concentrations of chloride in groundwater (i.e. 250 to 1460 mg/L) were found in wells east of Calgary to Strathmore in the Scollard and Horseshoe Canyon regions. North and east of Wetaskiwin there are three individual wells within the depth range with elevated chloride concentrations located in the Horseshoe Canyon and Bearspaw regions. Figure 4114.5 is a spatial distribution map for the concentrations of chloride over a depth of 60 to 100 mbgs. Most of the upper Paskapoo region has a chloride concentration of 0 to 40 mg/L. Concentrations ranging between 101 and 749 mg/L are found in wells in the Scollard and Horseshoe Canyon region. These elevated concentrations occur throughout the Scollard region past Drumheller to Wetaskiwin. Areas where water in the wells were found to exceed 250 mg/L of chloride area concentrated in the Calgary to Strathmore and Airdrie to Drumheller area, south of Wetaskawin and east of Camrose. There was also a group of 4 wells east of Camrose on the Bearspaw/Belly River region that have chloride levels of 1090 to 2050 mg/L. Wells with a total depth of more than 100 mbgs are shown in Figure 4114.6. The higher chloride concentration wells (41 to 990 mg/L) are found from the Bow River to Wetaskiwin along the Scollard region. Groundwater samples in this depth exceeding 250 mg/L of chloride are concentrated east of Calgary, near Wetaskawin and at some locations between Red Deer and Airdrie. Most other wells are in the 0 to 40 mg/L concentration range. Wells with no depth data are mapped in Figure 4114.7. The chloride concentration spatial distribution is very similar to that described for the wells displayed in Figure 4114.2 above. 4.2.5 Fluoride A total of 2,073 records or 25% indicate fluoride values that exceed maximum allowable fluoride concentration (1.5 mg/L) as directed by the Canadian Drinking Water Guidelines (2010). The livestock guideline is 1 2 mg/L and the irrigation guideline is 1 mg/L for fluoride. Figure 5 has Q3 for all depth ranges as being above 1 mg/L which has more than 25% of the wells in exceedance of the livestock and irrigation guidelines for fluoride. Of the 8,407 records, 897 analyses were below detection limit (0.1 mg/L). The median value for all data is 0.60 mg/L with 0.10 mg/L as the lower boundary and 316 mg/L as the upper boundary of all data values. A total of 25% of all the data lies below 0.20 mg/L and 75% of the data lies below 1.46 mg/L. Figure 5 below summarizes the median, 25% and 75% percentile and maximum fluoride concentrations for all depth ranges. The median concentrations of fluoride are similar from 0 to 60 mbgs and increase with depth from 60 mbgs to >100 mbgs. The range of concentrations increase with depth as indicated by the frequency distribution plots (Figure 4.115.1), and the Q1/Q3 results. All summary statistics for fluoride can be seen in section 4115.1 Appendix A.



Fluoride

0

2

4

6

8

10

12


Con

cent

ratio

n (m

g/L)

316 mg/L

Figure 5. Summary of Fluoride Statistics The spatial distribution of fluoride concentrations in the BWWT database were plotted to ascertain any spatial trends. Based on results summarized in Figure 4115.1 fluoride exceeds the drinking water guidelines in 18% of the wells from 0 to 30 mbgs, 8% of the wells from 30 to 60 mbgs, and 41% and 59% of the wells at depth ranges of 60 to 100 mbgs and >100 mbgs, respectively. Figure 4115.2 shows all fluoride results for all wells sampled in the BWWT. The fluoride concentrations are generally higher in the western and southern section of the sampling area. Fluoride concentrations are generally lower east of a line between Lacombe and Drumheller in the upper Paskapoo region. Similarly high fluoride concentrations in groundwater appear to occur in wells that are grouped in the upper Paskapoo and Scollard region east of Airdrie and Calgary. Wells sampled in the Willow creek region, south of the Calgary area, also show high fluoride concentrations. Wells with a total depth of less than 30 mbgs, show a similar distribution as the total fluoride map. Higher concentrations of fluoride in wells (i.e. 1.6 to 9.2 mg/L) occur along the western edge of the sampling area (i.e. Calgary to Red Deer and Wetaskawin) and in wells located east of Calgary to Strathmore area. Also higher fluoride concentrations are found in an area from Airdrie to the northeast towards Hanna and Three Hills (Figure 4115.3). Wells with a depth of 30 to 60 mbgs show a decrease in wells with higher fluoride concentrations. Many of the wells south of Red Deer still have fluoride concentrations above drinking water standard. Also, wells sampled to the east of Calgary have a high proportion of the groundwater samples with a fluoride concentration above the drinking water standard (Figure 4115.4). Figure 4115.5 and 4115.6 illustrates the spatial distribution of water wells with a depth of between 60 to 100 mbgs that were sampled for fluoride for the BWWT database. The mean



fluoride concentration of groundwater from these wells at this depth is above the drinking water standard. The majority of these wells are associated with the upper Paskapoo and Scollard regions. Wells with no depth data are mapped in Figure 4115.7. The fluoride concentration spatial distribution is very similar to that described for the total wells sampled in Figure 4115.2 above. 4.2.6 Dissolved Iron A total of 1,231 records or 15% of all records indicate iron values that exceed AO guidelines for iron concentrations (0.3 mg/L) as directed by the Canadian Drinking Water Guidelines (2010). The largest number of exceedances (17%) occurred in the shallowest wells (0-30 mgbs). Of the 8,406 records, 3,432 analyses were below detection limit (0.001 mg/L). The median value for all data is 0.02 mg/L with 0.001 mg/L as the lower boundary and 44 mg/L as the upper boundary for all data. A total of 25% of all the data lies below the detection limit of 0.001mg/L and 75% of the data lies below 0.12 mg/L. Most iron concentration is found within a range previously reported for water quality of groundwater existing within formations associated with the study area (Table 1). Figure 6 summarizes the median, 25% and 75% percentile and maximum iron concentrations for all depth ranges. The irrigation guideline (Table 3) for iron is 5 mg/L . All depth ranges have maximum values that exceed the irrigation guideline. All summary statistics for iron can be seen in section 4116.1, Appendix A.

Iron (dissolved)

0.0

0.1

0.2

0.3

0.4

0.5


Con

cent

ratio

n (m

g/L)

11 mg/L 34 mg/L 36 mg/L 29 mg/L

44 mg/L

Figure 6. Summary of Dissolved Iron Statistics The spatial distribution of dissolved iron concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 4116.2 shows all dissolved iron results for all wells sampled in the BWWT. The dissolved iron concentration appears to have no particular pattern with dissolved iron exceeding the aesthetic objectives (AO) 0.3 mg/L throughout the sampling area at all depth ranges.



4.2.7 Manganese A total of 1,635 records or 19% of all records indicate manganese values that exceed aesthetic objectives (0.05 mg/L) as directed by the Canadian Drinking Water Guidelines (2010). The greatest number of exceedances (40% or 594) occurs in the shallowest wells (0-30 mgbs) while the number of exceedances decreases with depth. Of the 8,407 records, 4,165 analyses were below the detection limit (0.001 mg/L). The median value for all data is 0.00 mg/L with Q1 and Q3 values of 0.001 and 0.03 mg/L respectively. The lowest value, above detection limit, reported was 0.001 mg/L and 191 mg/L is the upper boundary of all data values. The irrigation guideline for manganese is 0.2 mg/L. All depth ranges had maximum values above the irrigation guideline. Figure 7 below summarizes the median, 25% and 75% percentile and maximum manganese concentration for all depth ranges. All summary statistics for manganese can be seen in section 4117.1, Appendix A.

Manganese

0.000

0.050

0.100

0.150

0.200


Con

cent

ratio

n (m

g/L)

191 mg/L 24 mg/L 5 mg/L 0.7 mg/L

191 mg/L

Figure 7. Summary of Manganese Statistics The spatial distribution of manganese concentrations in the BWWT database was plotted to ascertain any spatial trends. Figure 4117.2 shows all manganese results for all wells sampled in the BWWT. Well water manganese concentrations exceeding either the aesthetic objectives (AO; 0.05 mg/L) or irrigation guidelines (0.2 mg/L) generally appear to be randomly distributed. An area south and east of Calgary and an area around Innisfail appear to have marginally lower manganese concentrations relative to the rest of the sampling area. Wells with a total depth of less than 30 mbgs are mapped in Figure 4117.3. Manganese concentrations of these samples indicate that many of the wells are above the AO limit and many are above the irrigation guidelines of 0.2 mg/L. Wells with a depth of 30 to 60 mbgs are shown in Figure 4117.4. These wells show trends of manganese concentrations that are similar to the overall trends observed in Figure 4117.2. with



an area of higher manganese concentrations in wells in the Airdrie and Three Hills area (Figure 4117.4) Figure 4117.5, illustrates the spatial distribution of water well with a depth of between 60 to 100 mbgs that were sampled for manganese for the BWWT database. No distinct manganese concentration distribution pattern can be observed for wells completed within this depth range. Figure 4117.6, illustrates the spatial distribution of water wells with a depth of greater than 100 mbgs that were sampled for manganese for the BWWT database. The manganese concentration is below the AO for most of the samples but manganese concentrations above 0.05 mg/L were observed near the boundary of the upper Paskapoo - Scollard regions. Wells with no depth data are mapped in Figure 4117.7. The manganese concentration spatial distribution is very similar to that described for the total wells sampled in Figure 4116.2. 4.2.8 Magnesium Of the 8,407 records, 669 analyses were below the detection limit (0.1 mg/L). The greatest median magnesium concentration of groundwater (5.5 mg/L) was observed for wells at shallow depths (100mbgs IB 90-110%

Con

cent

ratio

n (m

g/L)

514 mg/L 264 mg/L 253 mg/L 230 mg/L

514 mg/L

Figure 8. Summary of Magnesium Statistics



The spatial distribution of magnesium concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 4118.2 shows all magnesium results for all wells sampled in the BWWT. The highest magnesium concentrations are in the area south of Red Deer particularly in the upper Paskapoo region. Wells with a total depth of 14.6 mg/L. The highest concentrations of magnesium in wells (i.e. 86. mg/L to 514 mg/L) were again observed in the Airdrie to Drumheller area and north to Three Hills. In addition, a similar cluster is observed south of Calgary. The maximum magnesium concentration at this depth interval is 264 mg/L. Figure 4118.5 illustrates the spatial distribution of water wells with a depth of between 60 to 100 mbgs that were sampled for magnesium for the BWWT database. This depth range displayed only few high magnesium concentrations in the same location as in the two previous depth ranges. The maximum concentration for this depth range is 253 mg/L. Figure 4118.6, illustrates the spatial distribution of water wells with a depth of greater than 100 mbgs that were sampled for magnesium for the BWWT database. The magnesium concentration is below 14.6 mg/L for most groundwaters. Five wells had a magnesium concentration between 86.2 to 230 mg/L in the Airdrie to Drumheller region, and north towards the Three Hills area. Wells with no depth data are mapped in Figure 4118.7. The magnesium concentration spatial distribution is very similar to that described for the total wells sampled in Figure 4118.2. 4.2.9 Nitrate + Nitrite Of the 8,407 records for nitrate + nitrite, 5,784 analyses are below the detection limit (0.02 mg/L). The median value for all nitrate + nitrate concentration data is 0.02 mg/L. The data that falls within the 25th percentile and the 75 percentile ranges from 0.02 mg/L to 0.08 mg/L in concentration. All median values were 0.02 mg/L and of the depth ranges third quartile (75% of all data) are 0.02 mg/L. Figure 4119.1, Appendix A). Maximum and minimum recorded concentration values for all data were 424.0 mg/L and below the detection limit (BDL) respectively. Figure 9 summarizes the median, 25% and 75% percentile and maximum nitrate + nitrite concentrations for all depth ranges. The median values for all depth ranges were all the same (0.20 mg/L). All summary statistics for nitrate + nitrite can be seen in section 4119.1, Appendix A.



Nitrate + Nitrite

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0


Conc

entr

atio

n (m

g/L)

424 mg/L 137 mg/L 140 mg/L 60 mg/L

424 mg/L

Figure 9. Summary of Nitrate + Nitrite Statistics The spatial distribution of nitrate + nitrite concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 4119.2 shows all nitrate + nitrite results for all wells sampled in the BWWT. The highest nitrate + nitrite concentration values were found in two areas located south of Red Deer: from Airdrie to the northeast to Hanna/Three Hills; and, west of Calgary. Wells with a total depth of 10 mg/L) are found at the same locations as in the two previous depth ranges. The maximum nitrate + nitrite concentration for this depth range is 140 mg/L in a water sample collected at a well north of Drumheller near Hanna. Figure 4119.6 illustrates the spatial distribution of water wells with a depth of greater than 100 mbgs that were sampled for nitrate + nitrite for the BWWT database. The nitrate + nitrite concentrations are below 10 mg/L for most of the wells but two wells have a concentration



above 10 mg/L in the area just north of Airdrie and one east of Calgary. The highest concentration at this depth range is 60 mg/L. Wells with no depth data are mapped in Figure 4119.7. The nitrate + nitrite concentration spatial distribution is variable but concentrations over 10 mg/L are more prevalent south of Red Deer. Three wells with nitrate + nitrite concentrations over 100 mg/L were found between Red Deer and Drumheller and an additional three wells were located east of Calgary. Distributions are similar to those described for the total wells sampled in Figure 4119.2. 4.2.10 Nitrite Of the 8,398 records, 7,876 analyses were below the detection limit (0.02 mg/L). All median values and third quartile data (75% of all data) lay below the limit of detection. The maximum concentration value for all data was 889 mg/L. All summary statistics for nitrite can be seen in section 41110.1, Appendix A.

Nitrite

0.0

0.1

0.1

0.2

0.2

0.3

0.3

0.4

0.4

0.5

0.5


Con

cent

ratio

n (m

g/L

NO2-

-N) 7 mg/L 889 mg/L 65 mg/L 889 mg/L

Figure 10. Summary of Nitrite Statistics The spatial distribution of nitrite concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 41110.2 shows all nitrite results for all wells sampled in the BWWT. The highest nitrite concentrations were found in the area between Stettler/Red Deer and south of Airdrie/Drumheller and a second area just east of Calgary. There are only 3 wells where groundwater nitrite concentrations exceed the livestock guidelines of 10 mg/L. The vast majority of the wells within the study have groundwater with nitrite concentrations below 1 mg/L. Wells with a total depth of



Generally there are only a few wells that were found to have nitrite concentrations over 10 mg/L and these were randomly distributed. The majority of wells with groundwater nitrite concentrations > 1 mg/L are concentrated in an area roughly extending from Red Deer/Stettler to Calgary/Strathmore (Figures 41110.4 to 41110.7). There are more wells with groundwater nitrate >1 mg/L completed at shallow depths (i.e. 0 to 30 m) then at the deeper depth ranges. The maximum concentration for nitrite (889 mg/L) was found in a well located near Stettler and that was screened at the 30-60 meter depth range. This data entry is likely a data error as the nitrate and nitrate + nitrite results for this well are 14.3 and 0.017 mg/L respectively. 4.2.11 Nitrate - Nitrogen A total of 267 records or 3% of all records indicate nitrate (as nitrogen) values that exceed maximum allowable concentrations (10 mg/L NO3- - N) as directed by the Canadian Drinking Water Guidelines (2010). The greatest number of exceedances (5% or 143 wells) occurred in the shallowest well depth range (0-30 mgbs). Of the 8,407 records present within the database, 5,615 analyses were below detection limits (0.02 mg/L) and all median values lay below the limit of detection. Maximum and minimum concentration values for all data were 421 mg/L and BDL respectively. Figure 11 indicates the median value is the same for all depth ranges. All summary statistics for nitrate-N can be seen in section 41111.1, Appendix A.

Figure 11. Summary of Nitrate-N Statistics The spatial distribution of nitrate-N concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 41111.2 shows nitrate-N results for all wells sampled in the BWWT. The highest groundwater nitrate-N concentrations were found in the area south of Red Deer/Lacombe and east of Calgary in the sampling area. Only a minority of groundwater exceeded nitrate-N concentrations of 10 mg/L, the MAC.



Wells with a total depth of



Figure 12. Summary of Potassium Statistics The spatial distribution of potassium concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 41112.2 shows all potassium results for wells sampled in the BWWT. The highest potassium concentrations occurred in the area south of Red Deer and from Airdrie to the northeast, and in small areas southeast of Wetaskiwin and east of Calgary. The majority of the wells have a potassium concentration below 3 mg/L. The areas of lowest potassium concentration were found around Calgary and from Red Deer north to Wetaskiwin. Wells with a total depth of 18 mg/L) appear to be concentrated, but not limited, to a linear area stretching southwest to northeast between Airdrie and Stettler. There is a second group of wells with groundwater with higher potassium concentrations southeast of Wetaskiwin. Wells with a depth of 30 to 60 mbgs are shown in Figure 41112.4. The majority of the wells produced groundwater with potassium concentrations of 4 mg/L) appear concentrated in an area from Airdrie north to Lacombe. The maximum concentration at this depth interval is 174 mg/L of potassium. Figure 41112.5 illustrates the spatial distribution of water wells with a depth of between 60 to 100 mbgs that were sampled for potassium for the BWWT database. This depth range has a smaller proportion of wells with groundwater potassium concentrations >4 mg/L compared to the 0-30 mbgs or 30-60 mbgs depth ranges. The wells with elevated potassium concentrations are generally located between Airdrie, Drumheller and Red Deer. The maximum potassium concentration for this depth range is 87.7 mg/L.



Figure 41112.6 shows the spatial distribution of water wells with a depth of greater than 100 mbgs that were sampled for potassium for the BWWT database. The potassium concentration is below 4 mg/L for most groundwater samples from these wells in this depth range except for a small number of wells that are generally located along the eastern edge of the upper Paskapoo region. The maximum potassium concentration at this depth is 17 mg/L. Wells with no depth data are mapped in Figure 41112.7. The potassium concentration spatial distribution is very similar to that described for the total wells sampled in Figure 41112.2. The maximum potassium concentration in this group was 453 mg/L. 4.2.13 Sulphate A total of 2,064 records (25% of all records) indicate sulphate values that exceed drinking water aesthetic objectives (500 mg/L) as directed by the Canadian Drinking Water Guidelines (2010). The highest percentage of groundwater samples with sulphate concentrations exceeding aesthetic objectives occur from 0 to 60 mbgs. The percent of sulphate concentrations exceeding guidelines decrease with depth from 60 to greater than 100 m. Of the 8,407 total sulphate records, 286 analyses were below detection limit (0.1 mg/L). The median concentration value for all samples is 227 mg/L with 25% of all the data falling below 83.3 mg/L and 75% of the data falling below 490 mg/L. Maximum and minimum values for all sulphate data within the database were 9390.0 mg/L and BDL respectively. Most sulphate data is found within a range previously reported for groundwater quality existing within formations associated with the study area (Table 1). Figure 13 summarizes the median, 25% and 75% percentile and maximum sulphate concentrations for all depth ranges. Median ranges appear similar to a depth of 60 mbgs after which the median values decrease with depth. Such a trend may be consistent with bacterial sulphate reduction removing some sulphate preferably at depths of more than 60 mbgs. All summary statistics for sulphate can be seen in section 41113, Appendix A.

Sulphate

0

100

200

300

400

500

600

700

800


Con

cent

ratio

n (m

g/L)

4290 mg/L 2850 mg/L 6230 mg/L 4170 mg/L

9390 mg/L

Figure 13. Summary of Sulphate Statistics



The spatial distribution of sulphate concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 41113.2 shows all sulphate results for wells sampled in the BWWT. The highest sulphate concentrations (i.e. 500 mg/L or greater of sulphate) exceeding the AO are located in the area south of Red Deer. The area of greatest sulphate concentration is generally bounded by Airdrie, Drumheller and Stettler although the areas around Calgary, Nanton and Strathmore also have highs in sulphate concentrations of groundwater. There is an area of consistently lower sulphate concentration along the western edge of the sampling area from Olds to Ponoka where concentrations are below 268 mg/L. Wells with a depth of



for all data is 320 mg/L with 25% of all the data falling below 232 mg/L and 75% of the data falling below 434 mg/L. Figure 14 summarizes the median, 25% and 75% percentile and maximum sodium concentration for all depth ranges. All sodium data is found within a range previously reported for groundwater quality existing within formations associated with the study area (Table 1). All summary statistics for sodium can be seen in section 41114.1, Appendix A.

Figure 14. Summary of Sodium Statistics The spatial distribution of sodium concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 41114.2 shows all sodium results for wells sampled in the BWWT. The highest sodium concentrations (i.e. 592 mg/L or greater) in groundwater were observed in the sampling area south of Red DeerStettler to Calgary-Strathmore. Similarly high concentrations are found in clusters around the Nanton and the Ponoka area. This area also has most of the samples with sodium concentrations above the AO (i.e. 200 mg/L). There is an area of more consistently lower sodium concentrations in the middle of the sampling area from Red Deer to Ponoka where concentrations are below the AO of 200 mg/L. The distributions of elevated sodium concentrations are similar to those of high sulphate concentrations. Wells with a total depth of 30 mbgs or less are mapped in Figure 41114.3. The highest sodium concentrations were found in groundwater from wells located in a linear area between Airdrie and northeast through Three Hills also extending east to Hanna. There is also a cluster of elevated sodium concentrations in wells located between Calgary to Strathmore. The highest sodium concentration in this depth range is 1720 mg/L. Wells with a depth of 30 to 60 mbgs are shown in Figure 41114.4. The majority of the wells have a sodium concentration of more than 201 mg/L. The higher concentrations (592 mg/L or greater) are found in an area between Red Deer, Hanna and Airdrie. The maximum concentration at this depth interval is 1730 mg/L of sodium.



Figure 41114.5 illustrates the spatial distribution of water well with a depth of between 60 to 100 mbgs that were sampled for sodium for the BWWT database. The higher concentration wells (592 mg/L or greater) are located in a linear area between Airdrie and northeast through Three Hills also extending east to Hanna. There is also a cluster of wells with elevated sodium concentrations located between Calgary to Strathmore. The maximum sodium concentration for this depth range is 2570 mg/L. Figure 41114.6 shows the spatial distribution of water wells with a depth of greater than 100 mbgs that were sampled for sodium for the BWWT database. The sodium concentration is above 201 mg/L for most of the wells in this depth range. The higher concentration wells (592 mg/L or greater) are located in the linear area between Airdrie and northeast through Three Hills also extending east to Hanna. There is also a cluster of wells with elevated sodium concentrations located near Calgary. The maximum concentration at this depth is 2380 mg/L. Wells with no depth data are mapped in Figure 41114.7. The sodium concentration spatial distribution is very similar to that described for the total wells sampled in Figure 41114.2. The maximum sodium concentration in this group was 3470 mg/L. 4.2.15 Total Alkalinity Of the 8,403 records for alkalinity within the database, 8 analyses were below the detection limit (0.1 mg/L). The median value for all data is 512.0 mg/L with 25% of all the data falling below 398.0 mg/L and 75% of the data falling below 620.0 mg/L. Maximum and minimum concentration values for all data were 2730 mg/L and BDL respectively. There are three wells with a total alkalinity of 1,575,878 mg/L. These are either input errors or lab analysis errors. Figure 15 below summarizes the median, 25% and 75% percentile and maximum total alkalinity results for all depth ranges. Median values were similar for all depth ranges with median alkalinity being slightly higher from 30 to 100 mbgs. All summary statistics for total alkalinity can be seen in section 41115, Appendix A.



Total Alkalinity

0

100

200

300

400

500

600

700

800

900

1000


Con

cent

ratio

n (m

g/L)

2073 mg/L 2190 mg/L 1530 mg/L 2060 mg/L

2730 mg/L

Figure 15. Summary of Total Alkalinity Statistics The spatial distribution of total alkalinity concentrations in the BWWT database were plotted to ascertain any spatial trends. Figure 41115.2 shows all total alkalinity results for wells sampled in the BWWT. Generally, alkalinity is lower in the Paskapoo region and higher to the east in the Scollard to Horseshoe Canyon regions. The highest total alkalinity concentrations (i.e. 899 mg/L or greater) were found in groundwater from wells located in an area bounded by Olds, Strathmore, Hanna and Stettler. A second area of higher total alkalinity values is found between Drumheller to Strathmore. The higher total alkalinity concentration area corresponds to the Scollard Horseshoe Canyon region. There is an area of more consistently lower total alkalinity (below 421 mg/L) east of Airdrie and Calgary in the upper Paskapoo and Scollard regions. Wells with a total depth of 30 mbgs or less are mapped in Figure 41115.3. The highest total alkalinity concentrations are in the area between Red Deer, Stettler and Drumheller. Higher total alkalinity concentra

esrd - baseline water well testing report

Documents

baseline water

water quality of wells

study area

data representation

main area

calgary area

data entry issues

provincewide data