Acid-Sensitive LakesNine hundred and thirty-three lakes located in Saskatchewan, Alberta and the Northwest Territories were sampled to establish current acidification status. Of the 933 lakes, 244 (or 26%) are considered acid sensitive, almost always because of naturally low calcium and magnesium (or "base cation") concentrations. The most acid-sensitive lakes (i.e., those with extremely low base cation concentrations) are located on the Canadian Shield in both Alberta and Saskatchewan and east of the oils sands development area.Fifty-one of the 244 acid-sensitive lakes were sampled twice annually (spring and fall) to identify chemical changes through trend analyses. Results revealed that 55% of these lakes had concentrations of some metals in excess of Canadian Council of Ministers of the Environment guidelines. Of the 291 samples taken in the 51 lakes, iron concentrations were greater than guidelines in 36% (105 samples), aluminum in 33% (97 samples), lead in 0.3% (1 sample) and copper in 0.3% (1 sample). The metals in these lakes occur naturally and are expected to be found in a wide range of concentrations given the geology and physiography of the Canadian Shield. It remains to establish the relationship between acid sensitivity, geology and high metal concentrations.

In 2018, Fisheries and Oceans Canada initiated the Multidisciplinary Arctic Program (MAP) – Last Ice, the first ecosystem study of the poorly characterized region of Tuvaijuittuq, where multiyear ice still resides in the Arctic Ocean. The program MAP-Last Ice takes a coordinated approach to integrate the physical, biochemical, and ecological components of the sea ice-ocean connected ecosystem and its response to climate and ocean forcings. This program provides baseline ecological knowledge for Tuvaijuittuq and, in particular, for its unique multiyear ice ecosystem. The database provides baseline data on fatty acid composition and stable isotopes signatures of sea ice communities in multi- and first-year ice in Tuvaijuittuq. The data were collected during the 2018 spring field campaign of the MAP-Last Ice Program, offshore of Canadian Forces Station (CFS) Alert, in the Lincoln Sea.

Regional stream sediment geochemical data compilationNovember 2020Release notesThe regional stream sediment geochemical data compilation comprises data for more than 30 000 samples across Yukon. This compilation updates the work of Héon (2003). This new compilation includes results from the reanalysis of more than 24 000 samples; inductively coupled plasma mass spectrometry (ICPMS) analysis provides upgraded detection limits and a broader range of elements relative to previous analytical data. In addition to analytical data, efforts have been made to improve sample location accuracy. The data in this release are organized by analytical method with the geodatabase having six feature classes:1. RGS_SITE_WATER - site specific physiography and water quality data. These data are unchanged from the original releases. 2. RGS_HEON - the same data as released in Héon (2003) with minor updates to sample location. 3. RGS_AAS - all samples analyzed by atomic absorption spectrometry. Most of these data are superseded by INAA and ICPMS data. 4. RGS_INAA - all samples analyzed by instrumental neutron activation analysis (INAA) and fire assay-neutron activation (FA-NA) analysis. 5. RGS_ICPMS - all samples analyzed by inductively coupled plasma mass spectrometry (ICPMS). 6. RGS_All - includes all AAS, INAA and ICPMS data. Collection of stream sediment samples in Yukon began in 1976 and ended in 2006. Three analytical methods have been used to analyze the minus 0.177 mm fraction (-80 mesh) of these samples: AAS, INNA (and FA-NA) and ICPMS. A simple description of each method is given below.For atomic absorption spectrometry (AAS) a 1 g aliquot is 'partially digested' using Lefort aqua regia or concentrated hot nitric acid. The digestion product is analyzed using an atomic absorption spectrometer. Oxide and silicate minerals are partially digested while some sulphide minerals are erratically volatilized. This means that AAS cannot be used to obtain accurate REE, Ta, Nb, As, Sb, Sn, Hg, Cr, or Au determinations.For instrumental neutron activation analysis ( INAA), aliquots of sieved sediment (the minus 0.177 mm fraction) or milled rock ranging from 5 to 40 g are encapsulated and irradiated in a nuclear reactor before counting the primary gamma radiation induced by the neutron irradiation with a high resolution germanium gamma ray detector. Fire assay-neutron activation (FA-NA) analysis is similar but includes a pre-concentration fire assay step prior to irradiation and analysis. Results for both INAA and FA-NA are similar to those for samples analyses by fusion or other total digestion techniques. Neutron activation detection limits are typically higher than those by acid digestion - ICPMS. Commodity and pathfinder elements such as Au, As, Sb and W have reasonable detection limits by INAA and the data generated are relatively precise.For ICPMS analysis, aliquots of sieved sediment ( the minus 0.177 mm fraction) ranging from 0.5 to 1 g are prepared using a partial digestion technique, typically aqua regia, followed by analysis of dissolution product by ICPMS. Sulphide minerals are completely oxidized and dissolved whereas most oxide and silicate minerals are only partially digested. This means that results produced by partial digestion methods are acceptable for elements such as Ag, As, Mo, Ni, Pb, Sb, Tl, and Zn but values for elements such as Al, Ba, Cr, Fe, P, Sn, Ti, Y, and Zr are likely to not reflect the actual element concentration in a sample. The sample size used for routine RGS sample analysis is too small be representative of Au in the original sample and thus Au by aqua regia digestion - ICPMS has poor precision.Further upgrades to this database are not anticipated. All samples that could be found in the GSC-Ottawa warehouse have been reanalyzed using ICPMS. Any errors or omissions in this database should be reported to the Yukon Geological Survey. Your feedback contributes to improving the accuracy of the geoscience databases for Yukon.Contact: [YGSMinerals@yukon.ca](mailto:YGSMinerals@yukon.ca) ; [geology@yukon.ca](mailto:geology@yukon.ca)Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)

Regional stream sediment geochemical data compilationNovember 2020Release notesThe regional stream sediment geochemical data compilation comprises data for more than 30 000 samples across Yukon. This compilation updates the work of Héon (2003). This new compilation includes results from the reanalysis of more than 24 000 samples; inductively coupled plasma mass spectrometry (ICPMS) analysis provides upgraded detection limits and a broader range of elements relative to previous analytical data. In addition to analytical data, efforts have been made to improve sample location accuracy. The data in this release are organized by analytical method with the geodatabase having six feature classes:1. RGS_SITE_WATER - site specific physiography and water quality data. These data are unchanged from the original releases. 2. RGS_HEON - the same data as released in Héon (2003) with minor updates to sample location. 3. RGS_AAS - all samples analyzed by atomic absorption spectrometry. Most of these data are superseded by INAA and ICPMS data. 4. RGS_INAA - all samples analyzed by instrumental neutron activation analysis (INAA) and fire assay-neutron activation (FA-NA) analysis. 5. RGS_ICPMS - all samples analyzed by inductively coupled plasma mass spectrometry (ICPMS). 6. RGS_All - includes all AAS, INAA and ICPMS data. Collection of stream sediment samples in Yukon began in 1976 and ended in 2006. Three analytical methods have been used to analyze the minus 0.177 mm fraction (-80 mesh) of these samples: AAS, INNA (and FA-NA) and ICPMS. A simple description of each method is given below.For atomic absorption spectrometry (AAS) a 1 g aliquot is 'partially digested' using Lefort aqua regia or concentrated hot nitric acid. The digestion product is analyzed using an atomic absorption spectrometer. Oxide and silicate minerals are partially digested while some sulphide minerals are erratically volatilized. This means that AAS cannot be used to obtain accurate REE, Ta, Nb, As, Sb, Sn, Hg, Cr, or Au determinations.For instrumental neutron activation analysis ( INAA), aliquots of sieved sediment (the minus 0.177 mm fraction) or milled rock ranging from 5 to 40 g are encapsulated and irradiated in a nuclear reactor before counting the primary gamma radiation induced by the neutron irradiation with a high resolution germanium gamma ray detector. Fire assay-neutron activation (FA-NA) analysis is similar but includes a pre-concentration fire assay step prior to irradiation and analysis. Results for both INAA and FA-NA are similar to those for samples analyses by fusion or other total digestion techniques. Neutron activation detection limits are typically higher than those by acid digestion - ICPMS. Commodity and pathfinder elements such as Au, As, Sb and W have reasonable detection limits by INAA and the data generated are relatively precise.For ICPMS analysis, aliquots of sieved sediment ( the minus 0.177 mm fraction) ranging from 0.5 to 1 g are prepared using a partial digestion technique, typically aqua regia, followed by analysis of dissolution product by ICPMS. Sulphide minerals are completely oxidized and dissolved whereas most oxide and silicate minerals are only partially digested. This means that results produced by partial digestion methods are acceptable for elements such as Ag, As, Mo, Ni, Pb, Sb, Tl, and Zn but values for elements such as Al, Ba, Cr, Fe, P, Sn, Ti, Y, and Zr are likely to not reflect the actual element concentration in a sample. The sample size used for routine RGS sample analysis is too small be representative of Au in the original sample and thus Au by aqua regia digestion - ICPMS has poor precision.Further upgrades to this database are not anticipated. All samples that could be found in the GSC-Ottawa warehouse have been reanalyzed using ICPMS. Any errors or omissions in this database should be reported to the Yukon Geological Survey. Your feedback contributes to improving the accuracy of the geoscience databases for Yukon.Contact: [YGSMinerals@yukon.ca](mailto:YGSMinerals@yukon.ca) ; [geology@yukon.ca](mailto:geology@yukon.ca)Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)

Regional stream sediment geochemical data compilationNovember 2020Release notesThe regional stream sediment geochemical data compilation comprises data for more than 30 000 samples across Yukon. This compilation updates the work of Héon (2003). This new compilation includes results from the reanalysis of more than 24 000 samples; inductively coupled plasma mass spectrometry (ICPMS) analysis provides upgraded detection limits and a broader range of elements relative to previous analytical data. In addition to analytical data, efforts have been made to improve sample location accuracy. The data in this release are organized by analytical method with the geodatabase having six feature classes:1. RGS_SITE_WATER - site specific physiography and water quality data. These data are unchanged from the original releases. 2. RGS_HEON - the same data as released in Héon (2003) with minor updates to sample location. 3. RGS_AAS - all samples analyzed by atomic absorption spectrometry. Most of these data are superseded by INAA and ICPMS data. 4. RGS_INAA - all samples analyzed by instrumental neutron activation analysis (INAA) and fire assay-neutron activation (FA-NA) analysis. 5. RGS_ICPMS - all samples analyzed by inductively coupled plasma mass spectrometry (ICPMS). 6. RGS_All - includes all AAS, INAA and ICPMS data. Collection of stream sediment samples in Yukon began in 1976 and ended in 2006. Three analytical methods have been used to analyze the minus 0.177 mm fraction (-80 mesh) of these samples: AAS, INNA (and FA-NA) and ICPMS. A simple description of each method is given below.For atomic absorption spectrometry (AAS) a 1 g aliquot is 'partially digested' using Lefort aqua regia or concentrated hot nitric acid. The digestion product is analyzed using an atomic absorption spectrometer. Oxide and silicate minerals are partially digested while some sulphide minerals are erratically volatilized. This means that AAS cannot be used to obtain accurate REE, Ta, Nb, As, Sb, Sn, Hg, Cr, or Au determinations.For instrumental neutron activation analysis ( INAA), aliquots of sieved sediment (the minus 0.177 mm fraction) or milled rock ranging from 5 to 40 g are encapsulated and irradiated in a nuclear reactor before counting the primary gamma radiation induced by the neutron irradiation with a high resolution germanium gamma ray detector. Fire assay-neutron activation (FA-NA) analysis is similar but includes a pre-concentration fire assay step prior to irradiation and analysis. Results for both INAA and FA-NA are similar to those for samples analyses by fusion or other total digestion techniques. Neutron activation detection limits are typically higher than those by acid digestion - ICPMS. Commodity and pathfinder elements such as Au, As, Sb and W have reasonable detection limits by INAA and the data generated are relatively precise.For ICPMS analysis, aliquots of sieved sediment ( the minus 0.177 mm fraction) ranging from 0.5 to 1 g are prepared using a partial digestion technique, typically aqua regia, followed by analysis of dissolution product by ICPMS. Sulphide minerals are completely oxidized and dissolved whereas most oxide and silicate minerals are only partially digested. This means that results produced by partial digestion methods are acceptable for elements such as Ag, As, Mo, Ni, Pb, Sb, Tl, and Zn but values for elements such as Al, Ba, Cr, Fe, P, Sn, Ti, Y, and Zr are likely to not reflect the actual element concentration in a sample. The sample size used for routine RGS sample analysis is too small be representative of Au in the original sample and thus Au by aqua regia digestion - ICPMS has poor precision.Further upgrades to this database are not anticipated. All samples that could be found in the GSC-Ottawa warehouse have been reanalyzed using ICPMS. Any errors or omissions in this database should be reported to the Yukon Geological Survey. Your feedback contributes to improving the accuracy of the geoscience databases for Yukon.Contact: [YGSMinerals@yukon.ca](mailto:YGSMinerals@yukon.ca) ; [geology@yukon.ca](mailto:geology@yukon.ca)Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)

Regional stream sediment geochemical data compilationNovember 2020Release notesThe regional stream sediment geochemical data compilation comprises data for more than 30 000 samples across Yukon. This compilation updates the work of Héon (2003). This new compilation includes results from the reanalysis of more than 24 000 samples; inductively coupled plasma mass spectrometry (ICPMS) analysis provides upgraded detection limits and a broader range of elements relative to previous analytical data. In addition to analytical data, efforts have been made to improve sample location accuracy. The data in this release are organized by analytical method with the geodatabase having six feature classes:1. RGS_SITE_WATER - site specific physiography and water quality data. These data are unchanged from the original releases. 2. RGS_HEON - the same data as released in Héon (2003) with minor updates to sample location. 3. RGS_AAS - all samples analyzed by atomic absorption spectrometry. Most of these data are superseded by INAA and ICPMS data. 4. RGS_INAA - all samples analyzed by instrumental neutron activation analysis (INAA) and fire assay-neutron activation (FA-NA) analysis. 5. RGS_ICPMS - all samples analyzed by inductively coupled plasma mass spectrometry (ICPMS). 6. RGS_All - includes all AAS, INAA and ICPMS data. Collection of stream sediment samples in Yukon began in 1976 and ended in 2006. Three analytical methods have been used to analyze the minus 0.177 mm fraction (-80 mesh) of these samples: AAS, INNA (and FA-NA) and ICPMS. A simple description of each method is given below.For atomic absorption spectrometry (AAS) a 1 g aliquot is 'partially digested' using Lefort aqua regia or concentrated hot nitric acid. The digestion product is analyzed using an atomic absorption spectrometer. Oxide and silicate minerals are partially digested while some sulphide minerals are erratically volatilized. This means that AAS cannot be used to obtain accurate REE, Ta, Nb, As, Sb, Sn, Hg, Cr, or Au determinations.For instrumental neutron activation analysis ( INAA), aliquots of sieved sediment (the minus 0.177 mm fraction) or milled rock ranging from 5 to 40 g are encapsulated and irradiated in a nuclear reactor before counting the primary gamma radiation induced by the neutron irradiation with a high resolution germanium gamma ray detector. Fire assay-neutron activation (FA-NA) analysis is similar but includes a pre-concentration fire assay step prior to irradiation and analysis. Results for both INAA and FA-NA are similar to those for samples analyses by fusion or other total digestion techniques. Neutron activation detection limits are typically higher than those by acid digestion - ICPMS. Commodity and pathfinder elements such as Au, As, Sb and W have reasonable detection limits by INAA and the data generated are relatively precise.For ICPMS analysis, aliquots of sieved sediment ( the minus 0.177 mm fraction) ranging from 0.5 to 1 g are prepared using a partial digestion technique, typically aqua regia, followed by analysis of dissolution product by ICPMS. Sulphide minerals are completely oxidized and dissolved whereas most oxide and silicate minerals are only partially digested. This means that results produced by partial digestion methods are acceptable for elements such as Ag, As, Mo, Ni, Pb, Sb, Tl, and Zn but values for elements such as Al, Ba, Cr, Fe, P, Sn, Ti, Y, and Zr are likely to not reflect the actual element concentration in a sample. The sample size used for routine RGS sample analysis is too small be representative of Au in the original sample and thus Au by aqua regia digestion - ICPMS has poor precision.Further upgrades to this database are not anticipated. All samples that could be found in the GSC-Ottawa warehouse have been reanalyzed using ICPMS. Any errors or omissions in this database should be reported to the Yukon Geological Survey. Your feedback contributes to improving the accuracy of the geoscience databases for Yukon.Contact: [YGSMinerals@yukon.ca](mailto:YGSMinerals@yukon.ca) ; [geology@yukon.ca](mailto:geology@yukon.ca)Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)

Regional stream sediment geochemical data compilationNovember 2020Release notesThe regional stream sediment geochemical data compilation comprises data for more than 30 000 samples across Yukon. This compilation updates the work of Héon (2003). This new compilation includes results from the reanalysis of more than 24 000 samples; inductively coupled plasma mass spectrometry (ICPMS) analysis provides upgraded detection limits and a broader range of elements relative to previous analytical data. In addition to analytical data, efforts have been made to improve sample location accuracy. The data in this release are organized by analytical method with the geodatabase having six feature classes:1. RGS_SITE_WATER - site specific physiography and water quality data. These data are unchanged from the original releases. 2. RGS_HEON - the same data as released in Héon (2003) with minor updates to sample location. 3. RGS_AAS - all samples analyzed by atomic absorption spectrometry. Most of these data are superseded by INAA and ICPMS data. 4. RGS_INAA - all samples analyzed by instrumental neutron activation analysis (INAA) and fire assay-neutron activation (FA-NA) analysis. 5. RGS_ICPMS - all samples analyzed by inductively coupled plasma mass spectrometry (ICPMS). 6. RGS_All - includes all AAS, INAA and ICPMS data. Collection of stream sediment samples in Yukon began in 1976 and ended in 2006. Three analytical methods have been used to analyze the minus 0.177 mm fraction (-80 mesh) of these samples: AAS, INNA (and FA-NA) and ICPMS. A simple description of each method is given below.For atomic absorption spectrometry (AAS) a 1 g aliquot is 'partially digested' using Lefort aqua regia or concentrated hot nitric acid. The digestion product is analyzed using an atomic absorption spectrometer. Oxide and silicate minerals are partially digested while some sulphide minerals are erratically volatilized. This means that AAS cannot be used to obtain accurate REE, Ta, Nb, As, Sb, Sn, Hg, Cr, or Au determinations.For instrumental neutron activation analysis ( INAA), aliquots of sieved sediment (the minus 0.177 mm fraction) or milled rock ranging from 5 to 40 g are encapsulated and irradiated in a nuclear reactor before counting the primary gamma radiation induced by the neutron irradiation with a high resolution germanium gamma ray detector. Fire assay-neutron activation (FA-NA) analysis is similar but includes a pre-concentration fire assay step prior to irradiation and analysis. Results for both INAA and FA-NA are similar to those for samples analyses by fusion or other total digestion techniques. Neutron activation detection limits are typically higher than those by acid digestion - ICPMS. Commodity and pathfinder elements such as Au, As, Sb and W have reasonable detection limits by INAA and the data generated are relatively precise.For ICPMS analysis, aliquots of sieved sediment ( the minus 0.177 mm fraction) ranging from 0.5 to 1 g are prepared using a partial digestion technique, typically aqua regia, followed by analysis of dissolution product by ICPMS. Sulphide minerals are completely oxidized and dissolved whereas most oxide and silicate minerals are only partially digested. This means that results produced by partial digestion methods are acceptable for elements such as Ag, As, Mo, Ni, Pb, Sb, Tl, and Zn but values for elements such as Al, Ba, Cr, Fe, P, Sn, Ti, Y, and Zr are likely to not reflect the actual element concentration in a sample. The sample size used for routine RGS sample analysis is too small be representative of Au in the original sample and thus Au by aqua regia digestion - ICPMS has poor precision.Further upgrades to this database are not anticipated. All samples that could be found in the GSC-Ottawa warehouse have been reanalyzed using ICPMS. Any errors or omissions in this database should be reported to the Yukon Geological Survey. Your feedback contributes to improving the accuracy of the geoscience databases for Yukon.Contact: [YGSMinerals@yukon.ca](mailto:YGSMinerals@yukon.ca) ; [geology@yukon.ca](mailto:geology@yukon.ca)Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)

Regional stream sediment geochemical data compilationNovember 2020Release notesThe regional stream sediment geochemical data compilation comprises data for more than 30 000 samples across Yukon. This compilation updates the work of Héon (2003). This new compilation includes results from the reanalysis of more than 24 000 samples; inductively coupled plasma mass spectrometry (ICPMS) analysis provides upgraded detection limits and a broader range of elements relative to previous analytical data. In addition to analytical data, efforts have been made to improve sample location accuracy. The data in this release are organized by analytical method with the geodatabase having six feature classes:1. RGS_SITE_WATER - site specific physiography and water quality data. These data are unchanged from the original releases. 2. RGS_HEON - the same data as released in Héon (2003) with minor updates to sample location. 3. RGS_AAS - all samples analyzed by atomic absorption spectrometry. Most of these data are superseded by INAA and ICPMS data. 4. RGS_INAA - all samples analyzed by instrumental neutron activation analysis (INAA) and fire assay-neutron activation (FA-NA) analysis. 5. RGS_ICPMS - all samples analyzed by inductively coupled plasma mass spectrometry (ICPMS). 6. RGS_All - includes all AAS, INAA and ICPMS data. Collection of stream sediment samples in Yukon began in 1976 and ended in 2006. Three analytical methods have been used to analyze the minus 0.177 mm fraction (-80 mesh) of these samples: AAS, INNA (and FA-NA) and ICPMS. A simple description of each method is given below.For atomic absorption spectrometry (AAS) a 1 g aliquot is 'partially digested' using Lefort aqua regia or concentrated hot nitric acid. The digestion product is analyzed using an atomic absorption spectrometer. Oxide and silicate minerals are partially digested while some sulphide minerals are erratically volatilized. This means that AAS cannot be used to obtain accurate REE, Ta, Nb, As, Sb, Sn, Hg, Cr, or Au determinations.For instrumental neutron activation analysis ( INAA), aliquots of sieved sediment (the minus 0.177 mm fraction) or milled rock ranging from 5 to 40 g are encapsulated and irradiated in a nuclear reactor before counting the primary gamma radiation induced by the neutron irradiation with a high resolution germanium gamma ray detector. Fire assay-neutron activation (FA-NA) analysis is similar but includes a pre-concentration fire assay step prior to irradiation and analysis. Results for both INAA and FA-NA are similar to those for samples analyses by fusion or other total digestion techniques. Neutron activation detection limits are typically higher than those by acid digestion - ICPMS. Commodity and pathfinder elements such as Au, As, Sb and W have reasonable detection limits by INAA and the data generated are relatively precise.For ICPMS analysis, aliquots of sieved sediment ( the minus 0.177 mm fraction) ranging from 0.5 to 1 g are prepared using a partial digestion technique, typically aqua regia, followed by analysis of dissolution product by ICPMS. Sulphide minerals are completely oxidized and dissolved whereas most oxide and silicate minerals are only partially digested. This means that results produced by partial digestion methods are acceptable for elements such as Ag, As, Mo, Ni, Pb, Sb, Tl, and Zn but values for elements such as Al, Ba, Cr, Fe, P, Sn, Ti, Y, and Zr are likely to not reflect the actual element concentration in a sample. The sample size used for routine RGS sample analysis is too small be representative of Au in the original sample and thus Au by aqua regia digestion - ICPMS has poor precision.Further upgrades to this database are not anticipated. All samples that could be found in the GSC-Ottawa warehouse have been reanalyzed using ICPMS. Any errors or omissions in this database should be reported to the Yukon Geological Survey. Your feedback contributes to improving the accuracy of the geoscience databases for Yukon.Contact: [YGSMinerals@yukon.ca](mailto:YGSMinerals@yukon.ca) ; [geology@yukon.ca](mailto:geology@yukon.ca)Distributed from [GeoYukon](https://yukon.ca/geoyukon) by the [Government of Yukon](https://yukon.ca/maps) . Discover more digital map data and interactive maps from Yukon's digital map data collection.For more information: [geomatics.help@yukon.ca](mailto:geomatics.help@yukon.ca)

Historical finds of Pristiphora erichsonii

The Canadian Environmental Sustainability Indicators (CESI) program provides data and information to track Canada's performance on key environmental sustainability issues. These indicators track facility-based releases to water of 4 substances that are defined as toxic under the Canadian Environmental Protection Act, 1999: mercury, lead, cadmium and arsenic and their compounds. For each substance, data are provided at the national, regional (provincial and territorial) and facility level, as well as by source. The indicators inform Canadians about releases to water of these 4 substances from facilities in Canada. The Releases of harmful substances to water indicators also help the government to identify priorities and develop or revise strategies to inform further risk management and to track progress on policies put in place to reduce or control these 4 substances and water pollution in general.Information is provided to Canadians in a number of formats including: static and interactive maps, charts and graphs, HTML and CSV data tables and downloadable reports. See the supplementary documentation for the data sources and details on how the data were collected and how the indicator was calculated.Canadian Environmental Sustainability Indicators: https://www.canada.ca/environmental-indicators