Hydrogeologic Sensitivity of the Water Table Aquifer

Metadata also available as

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator:
Minnesota Department of Health, Environmental Health, Drinking Water Protection
Publication_Date: 20160222
Title: Hydrogeologic Sensitivity of the Water Table Aquifer
Geospatial_Data_Presentation_Form: raster digital data
Online_Linkage: <http://www.health.state.mn.us/divs/eh/water/swp/maps/index.htm>
Description:
Abstract:
Minnesota Department of Health (MDH) Source Water Protection initially developed county-scale nitrate risk maps in 2007 for nine southeastern Minnesota counties to assist with state and local water quality planning efforts and support a nitrate occurrence study (Southeast Minnesota Water Resources Board, 2009). Hydrogeologic sensitivity mapping was done as part of the nitrate risk mapping effort. Hydrogeologic sensitivity of the water table aquifer was generated using guidelines provided in Minnesota DNR (1991). Areas were ranked as low, moderate, high, or very high hydrogeologic sensitivity based on permeability of near-surface bedrock or unconsolidated geologic materials, estimated depth to water, and land slope. LOW (1 point) was assigned to areas 1) covered by geologic materials primarily composed of clay or shale close to the surface, or 2) where land slopes were greater than 12% (regardless of underlying geologic materials).MODERATE (2 points) was assigned to areas not already assigned LOW, and underlain by modified clay till (clay plus a significant sand or gravel fraction). MODERATE was also assigned where land slopes were at least 6% and at most 12% (regardless of the rank of underlying geologic materials, except that material already ranked LOW remained LOW).HIGH (3 points) was assigned to areas not already assigned LOW or MODERATE, and underlain by unconsolidated sands and gravels. HIGH was also assigned to areas where limestone, dolomite, or sandstone were close to the surface and covered by loess. VERY HIGH (4 points) was assigned to areas not already assigned LOW, MODERATE or HIGH, where loess was absent, and shallow bedrock was limestone, dolomite, or sandstone.
Purpose:
Hydrogeologic sensitivity is defined as the likelihood that an aquifer will remain isolated from contaminants due to intrinsic physical attributes of the geologic setting or geomorphology.
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -96.502240
East_Bounding_Coordinate: -90.435454
North_Bounding_Coordinate: 47.263585
South_Bounding_Coordinate: 43.452660
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Hydrogeologic
Theme_Keyword: Geology
Theme_Keyword: Hydrology
Theme_Keyword: Sensitivity
Access_Constraints: None
Use_Constraints:
The maps are designed to be used at a scale of approximately 1:100,000 (county-scale). Map accuracy at larger scales (more detail or smaller area) cannot be verified due to the scale limitations on the base data used to generate the maps.
Data_Set_Credit:
Base data from National Agricultural Statistics Service, various county soil atlases, Minnesota Geological Survey's County Well Index, and MDH Environmental Health Division, Drinking Water Protection Section, Source Water Protection Unit. Final datasets prepared by MDH Source Water Protection Unit.
Native_Data_Set_Environment: Version 6.2 (Build 9200) ; Esri ArcGIS 10.2.2.3552

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 7467
Column_Count: 8202

Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: NAD 1983 UTM Zone 15N
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.9996
Longitude_of_Central_Meridian: -93.0
Latitude_of_Projection_Origin: 0.0
False_Easting: 500000.0
False_Northing: 0.0
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000000002220024164500956
Ordinate_Resolution: 0.000000002220024164500956
Planar_Distance_Units: meter
Geodetic_Model:
Horizontal_Datum_Name: D North American 1983
Ellipsoid_Name: GRS 1980
Semi-major_Axis: 6378137.0
Denominator_of_Flattening_Ratio: 298.257222101

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: SWP.SDE_VAT_43
Attribute:
Attribute_Label: OBJECTID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: Esri
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: VALUE
Attribute_Definition:
The VALUE field numerically classifies the hydrogeologic sensitivity as 1 (low), 2 (moderate), 3 (high), 4 (very high), or 9 (not evaluated)
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 1
Enumerated_Domain_Value_Definition: Low hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: 2
Enumerated_Domain_Value_Definition: Moderate hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: 3
Enumerated_Domain_Value_Definition: High hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: 4
Enumerated_Domain_Value_Definition: Very High hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: 9
Enumerated_Domain_Value_Definition: Not Evaluated
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Attribute:
Attribute_Label: COUNT
Attribute:
Attribute_Label: SENSITIVITY
Attribute_Definition:
Classifies the hydrogeologic sensitivity based on permeability of near-surface geologic materials, whether the water table occurred in bedrock or unconsolidated materials, and land slope.
Attribute_Definition_Source: Minnesota Department of Health
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Low
Enumerated_Domain_Value_Definition: Low hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: Moderate
Enumerated_Domain_Value_Definition: Moderate hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: High
Enumerated_Domain_Value_Definition: High hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: Very High
Enumerated_Domain_Value_Definition: Very High hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health
Enumerated_Domain:
Enumerated_Domain_Value: Not Evaluated
Enumerated_Domain_Value_Definition:
Insufficient information to evaluate the hydrogeologic sensitivity
Enumerated_Domain_Value_Definition_Source: Minnesota Department of Health

Distribution_Information:
Distribution_Liability: See access and use constraints information.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: ESRI raster

Metadata_Reference_Information:
Metadata_Date: 20160222
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Minnesota Department of Health
Contact_Person: James Lundy
Contact_Position: Hydrologist Supervisor
Contact_Address:
Address_Type: physical
Address: 625 Robert Street North
City: Saint Paul
State_or_Province: Minnesota
Postal_Code: 55164-0975
Country: US
Contact_Voice_Telephone: 651-201-4649
Contact_Electronic_Mail_Address: james.lundy@state.mn.us
Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Use_Constraints:
The maps are designed to be used at a scale of approximately 1:100,000 (county-scale). Map accuracy at larger scales (more detail or smaller area) cannot be verified due to the scale limitations on the base data used to generate the maps.

Generated by mp version 2.9.12 on Mon Feb 22 10:03:28 2016