Pollution Sensitivity of Near-Surface Materials
Go to Section:- Overview
- Data Quality
- Data Organization
- Coordinate System
- Attributes
- Distribution - Get Data
- Metadata Reference
Section 1: Overview
Originator:Minnesota Department of Natural Resources, County Geologic Atlas Program
Title:
Pollution Sensitivity of Near-Surface Materials
Abstract:
This dataset estimates the pollution sensitivity of near-surface materials from the transmission time of water through 3 feet of soil and 7 feet of surficial geology, to a depth of 10 feet from the land surface.
Purpose:
This dataset was developed to provide a statewide estimate of pollution sensitivity of near-surface materials, for use by both the public and state regulators for planning and modeling.
Time Period of Content Date:
10/31/2018
Currentness Reference:
Date range for source material is 1995 to Time Period of Content.
Progress:
Complete
Maintenance and Update Frequency:
Irregular
Spatial Extent of Data:
Minnesota
Bounding Coordinates:
-97.23
-89.53
49.37
43.5
Place Keywords:
Minnesota
Theme Keywords:
near surface, pollution sensitivity, sensitivity, recharge, transmission
Theme Keyword Thesaurus:
Access Constraints:
None
Use Constraints:
Users may wish to verify critical information; sources include both the references here and information on file in the offices of the Minnesota Geological Survey and the Minnesota Department of Natural Resources. Every effort has been made to ensure the interpretation shown conforms to sound geologic and cartographic principles. This map should not be used to establish legal title, boundaries, or locations of improvements.
Contact Person Information:
Holly Johnson,
GIS Specialist
Minnesota Department of Natural Resources
500 Lafayette Rd
St. Paul,
MN
55155-4025
Phone: 651-259-5693
Email: holly.je.johnson@state.mn.us
Section 2: Data Quality
Attribute Accuracy:
1:500,000
Logical Consistency:
Completeness:
Complete
Horizontal Positional Accuracy:
Lineage:
Pollution sensitivity of near-surface materials was derived from the following datasets in ArcGIS 10.2.2:
- NRCS soil survey tabular and spatial data, using the hydrologic soil groups for transmission rate determination. SSURGO was the primary source of soil data. Where it was unavailable, STATSGO2 was used to fill in the coverage gaps. Both sets of data provided hydrologic soil groups. STATSGO2 data have a coarser scale than SSURGO data.
- Surficial geology coverage was delineated from multiple MGS maps. These maps, accompanied by the surficial geology unit texture database created by MGS, are correlated with estimates for transmission rates through surficial geology units. See Table 2 in HG-02:
http://files.dnr.state.mn.us/waters/groundwater_section/mapping/mha/hg02_report.pdf.
The units in a given location are determined from the following surficial geology maps: C-08, C-10, C-11, C-12, C-13, C-14, C-15, C-16, C-17, C-18, C-19, C-20, C-21, C-22, C-23, C-24, C-25, C-26, C-27, C-28, C-29- C-30, C-31, C-32, C-33, C-34, C-35, C-39, S-01, M-107, M-130, M-131, M-156, M-164, M-178, M-180, OFR 07-02, OFR 09-01, OFR 10-01, OFR 16-03. In portions of northwest Minnesota, the extent of thick Lake Agassiz clay from Breckenridge (2015) is used to determine the texture instead of the local surficial geology map.
- Transmission rates for particular soil or surficial geologic textures are estimated by converting published saturated hydraulic conductivity rates to unsaturated rates. These rates are then used to develop soil and surficial geology maps in a geographic information system (GIS), creating a two-layer model. For the first layer of this model the Hydrologic Soil Group from individual soil units is used to determine the transmission rate for that soil unit. For the second layer the DNR uses the dominant textures of surficial geology units to assign transmission rates. See Table 2 in HG-02 (link available above).
- The general approach used to create the maps is as follows: (A) GIS polygons from soil and surficial geologic units are converted to rasters with 30-meter cells, with their transmission rates as the cell value. (B) Conditional statements are used to calculate travel time given the availability of soil and surficial geology data at a specific location where soil and surficial geology raster cells are coincident.
- The two-layer model was applied to large portions of the state, however, special conditions override this approach for regions where unique geological environments dominate: karst, bedrock at or near surface, north-central peatlands, and large areas of disturbed land. The delineation of karst is from GW-01 Minnesota Regions Prone to Surface Karst Feature Development. The north-central peatlands are delineated from the Ecological Land Type Associations of Minnesota; the bedrock at or near surface and the disturbed lands are from surficial geology maps.
Section 3: Spatial Data Organization (not used in this metadata)
Section 4: Coordinate System
Horizontal Coordinate Scheme:
Universal Transverse Mercator
UTM Zone Number:
15
Horizontal Datum:
NAD83
Horizontal Units:
meters
Vertical Datum:
Vertical Units:
Depth Datum:
Depth Units:
Section 5: Attributes
Overview:
These data display the time it takes water to a travel a depth of 10 feet.
Detailed Citation:
Table Detail:
nrsfsn| Field Name | Valid Values | Definition | Definition Source |
|---|
| RATING | enumerated | geologic sensitivity rating of the near surface as defined by vertical travel time | |
| High | <=170 hours | |
| Moderate | >170-430 hours | |
| Low | >430-1600 hours | |
| Very low | >1600-8000 hours | |
| Ultra low | >8000 hours | |
| Karst | Special condition | |
| Peatlands | Special condition | |
| Bedrock at or near surface | Special condition | |
| Disturbed lands | Special condition | |
| Water | Not rated | |
Section 6: Distribution
Publisher:
Minnesota Department of Natural Resources
Publication Date:
06/30/2016
Contact Person Information:
Holly Johnson,
GIS Specialist
Minnesota Department of Natural Resources
500 Lafayette Rd
St. Paul,
MN
55155-4025
Phone: 651-259-5693
Email: holly.je.johnson@state.mn.us
Distributor's Data Set Identifier:
HG-02
Distribution Liability:
These data were compiled and generated in a geographic information system (GIS) from publicly available information only. Every reasonable effort has been made to ensure the accuracy of the factual data on which the individual interpretations were based. However, the DNR does not warrant the accuracy, completeness, or any implied uses of these data. Users may wish to verify critical information; sources include both the references here and the information on file in the offices of the Minnesota Department of Natural Resources.
Ordering Instructions:
Please visit the download page for this dataset on the Minnesota Geospatial Commons website using the web link below (Online Linkage). Online Linkage: I AGREE
to the notice in "Distribution Liability" above. Clicking to agree will either begin the download process, link to a service, or provide more instructions. See "Ordering Instructions" above for details.
Section 7: Metadata Reference
Metadata Date:
11/08/2018
Contact Person Information:
Holly Johnson,
GIS Specialist
Minnesota Department of Natural Resources
500 Lafayette Rd
St. Paul,
MN
55155-4025
Phone: 651-259-5693
Email: holly.je.johnson@state.mn.us
Metadata Standard Name:
Minnesota Geographic Metadata Guidelines
Metadata Standard Version:
1.2
