# nrsfsnpy

This page last updated: 01/17/2017
Metadata created using Minnesota Geographic Metadata Guidelines

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1. Overview
2. Data Quality
3. Data Organization
4. Coordinate System
5. Attributes
6. Distribution - Get Data
7. Metadata Reference

## Section 1: Overview

Originator:Minnesota Department of Natural Resources
Title: nrsfsnpy
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: Sibley County Geologic Atlas, Part B, County Geologic Atlas Series C-24
Time Period of Content Date:
Currentness Reference: Data were obtained in 2015 and re-evaluated in April 2016. Date range for source material is 1995-2015.
Progress: Complete
Maintenance and Update Frequency: None Planned
Spatial Extent of Data: Sibley County, Minnesota
Bounding Coordinates: -94.64
-93.76
44.72
44.45
Place Keywords: Sibley County, Minnesota
Theme Keywords: pollution sensitivity, near surface
Theme Keyword Thesaurus: None
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
Browse Graphic: None available
Associated Data Sets: Sibley County Geologic Atlas, Part A, County Geologic Atlas Series C-24, published by the Minnesota Geological Survey (MGS), 2011. More information and downloadable data for Part A are available on the MGS data site: http://www.mngs.umn.edu/county_atlas/countyatlas.htm
Minnesota Hydrogeology Atlas HG-02: http://www.dnr.state.mn.us/waters/programs/gw_section/mapping/platesum/mha_ps-ns.html

## Section 2: Data Quality

Attribute Accuracy: 1:100,000
Logical Consistency: Data are topologically correct using ArcGIS 10.4.1
Completeness: Complete
Horizontal Positional Accuracy: File was snapped to statewide 30 meter LiDAR data.
Vertical Positional Accuracy: NA
Lineage: The pollution sensitivity of near-surface materials is an estimate of the time it takes for water to infiltrate the land surface to a depth of 10 feet. It is intended to estimate the time of travel through the unsaturated zone to reach the water table, which for the purposes of this method, is assumed to be 10 feet below land surface everywhere.
The matrix texture of a geological unit is determined from the fraction of the material that is less than 2 millimeters in size, and is described by the percent sand, silt, and clay of this fraction. The matrix texture is used as a proxy for estimating the transmission rate, as coarse-grained materials have transmission rates greater than fine-grained materials because of the larger and more connected pore spaces between the grains. The transmission rate is estimated with a two-layer approach using two primary inputs: NRCS data for the soil layer (0 to 3 feet) and the surficial geologic map for underlying geologic materials (3 to 10 feet). The transmission rate of the soil layer is derived from the Hydrologic Soil Group, which is a proxy for texture. Special conditions override this approach for regions where the geology dominates.
Pollution sensitivity of near-surface materials was derived from the following datasets:
- 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 the Sibley County (C-24) surficial geology map from the MGS. The map units were joined with the surficial geology unit texture database created by MGS.
Transmission rates for the soil layer and the surficial geology layer are determined by correlating the hydrologic soil group and the matrix texture, respectively, with the transmission rates shown in Table 2 in HG-02: files.dnr.state.mn.us/waters/groundwater_section/mapping/mha/hg02_report.pdf.
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.
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 bedrock at or near surface is from surficial geology maps. The north-central peatlands are delineated from the Ecological Land Type Associations of Minnesota and the disturbed lands are from surficial geology maps; neither of these conditions exist within the county.

## 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

## Section 5: Attributes

Overview:
Detailed Citation:
Table Detail:

NRSFSNPY
Field Name | Valid Values | Definition | Definition Source
--- | --- | --- | ---
RATING | enumerated |  |
| nsH | hours to a week |
| nsM | a week to weeks |
| nsL | weeks to months |
| nsVL | months to a year |
| karst | special condition: potentially very rapid infiltration conditions |
| bedrock | special condition: bedrock conditions at or near surface |
| water | not rated |

## Section 6: Distribution

Publisher: Minnesota Department of Natural Resources, Ecological and Water Resources Division
Publication Date: 01/17/2017
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: nrsfspy
Distribution Liability: These data were prepared from publicly available information only. Every reasonable effort has been made to ensure the accuracy of the factual data on which these files are based. However, the Department of Natural Resources 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 information on file in the offices of the Department of Natural Resources.
Ordering Instructions: Download zip file of metadata and feature classes by clicking "I AGREE" below.
PDFs of the Sibley County Geologic Atlas plates can be downloaded at: http://www.dnr.state.mn.us/waters/programs/gw_section/mapping/platesum/siblcga.html
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: 01/17/2017
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
Metadata Standard Online Linkage: http://www.mngeo.state.mn.us/committee/standards/mgmg/metadata.htm

This page last updated: 01/17/2017
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