Information on sole source aquifers (SSAs) is widely used in assessments under the National Environmental Policy Act and at
the state and local level. A national layer, including all available SSA coverages, is available for use in GIS. This layer
includes the GIS polygons for SSAs. In addition to single SSA designated area polygons, some EPA regional offices have delineated
GIS layers for: * Streamflow zones * Aquifer recharge areas * Other features at the land surface important for SSA designations.
The SSA geospatial data set is available through Data.gov for use by government agencies, private organizations, and the public.
Citation
Title EPA Sole Source Aquifers
publication Date
2016-10-14
cited responsible party
-
publisher
organisation Name
U.S. EPA Office of Water (OW)
Contact information
Address
, Washington, D.C.
cited responsible party
-
originator
organisation Name
US Environmental Protection Agency
Title U.S. Department of Commerce, 1995, Countries, Dependencies, Areas of Special Sovereignty, and Their Principal Administrative
Divisions (Federal Information Processing Standard (FIPS) 10-4): Washington, DC, National Institute of Standards and Technology.
purpose:
The SSA protection program is authorized by section 1424(e) of the Safe Drinking Water Act of 1974 (Public Law 93-523, 42
U.S.C. 300 et seq.). This program is designed to protect drinking water supplies in areas with few or no alternative sources
to the ground water resource, and where, if contamination occurred, using an alternative source would be extremely expensive.
EPA defines a sole or principal source aquifer as an aquifer that supplies at least 50 percent of the drinking water consumed
in the area overlying the aquifer. These areas may have no alternative drinking water source(s) that could physically, legally
and economically supply all those who depend on the aquifer for drinking water. For convenience, all designated sole or principal
source aquifers are referred to as "sole source aquifers" (SSAs). The designation protects an area's ground water resource
by requiring EPA to review certain proposed projects within the designated area. All proposed projects receiving federal funds
are subject to review to ensure that they do not endanger the water source.
Resource language:
eng; USA
Resource progress code:
completed
Resource Maintenance Information
maintenance or update frequency:
asNeeded
Constraints on resource usage:
Constraints
Use limitation statement:
https://edg.epa.gov/EPA_Data_License.htm
Constraints on resource usage:
Legal Constraints
use constraint:
otherRestrictions
Other constraints
Use Constraints: None.
Constraints on resource usage:
Legal Constraints
Access Constraints
otherRestrictions
Other constraints
Access Constraints: None.
Constraints on resource usage:
Security Constraints
Classification
PUBLIC
Classification
System http://project-open-data.github.io/schema/#accessLevel
Handling
Description Standard Technical Controls
Resource extent
Geographic Extent
Geographic Bounding Box
westBoundLongitude
-138.21454852
eastBoundLongitude
-12.68151645
northBoundLatitude
61.7110157
southBoundLatitude
6.65223303
Temporal Extent
2016-10-14
point of contact
-
pointOfContact
individual Name Brianna Knoppow
organisation Name
U.S. Environmental Protection Agency, Office of Water
descriptor Character string of the form "SSA_##" providing an identifier for the SSA designations. Since a given SSA can be located in
more than a single county, a concatenation of the SSA_ID and the FIPS code are needed to establish a unique database key.
Where polygons are provided for streamflow zones or other special features related to the SSA designations, the SSA_ID takes
the form of SSA##a, SSA##b, or SSA##b. An example for an SSA designation involving 3 polygons areas is: SSA46a Edwards Aquifer
II (Austin Area) SSA - Streamflow Source Zone 53 FR 20897 (1988); SSA46b Edwards Aquifer II (Austin Area) SSA -Recharge Zone
53 FR 20897 (1988); SSA46c Edwards Aquifer II (Austin Area) SSA - Artesian Zone 53 FR 20897 (1988).
sequence Identifier
name SSA_ID
Band
descriptor The name of the SSA taken from the Federal Register and corresponding to a given SSA. The name will contain information related
to the streamflow zone or other special features related to a specific polygon.
sequence Identifier
name SSA_NAME
Band
descriptor Character string of the form "## FR #### (YYYY)" providing an identifier for the Federal Register citation for the SSA designations.
Attribute_Definition_Source: Computed based on SSA_IDs developed for the Drinking Water Mapping Application and information
in Federal Register Notices and GIS attributes in polygons supplied from the EPA Regions.
sequence Identifier
name Federal Register ID
Band
descriptor The sole source aquifer coordinator for that aquifer's region
sequence Identifier
name SSA Coordinator
Band
descriptor The phone number of the sole source aquifer coordinator for that aquifer's region
sequence Identifier
name Phone Number
Band
descriptor The email address of the sole source aquifer coordinator for that aquifer's region
name Of Measure Horizontal Positional Accuracy Report
evaluation Method Description
Positional accuracy for the data set varies for individual features within the data set. Actual horizontal positional accuracy
for the data set is unknown.
AbsoluteExternalPositionalAccuracy
name Of Measure Vertical Positional Accuracy Report
evaluation Method Description
Statements of vertical positional accuracy for elevation of water surfaces are based on accuracy statements made for USGS
topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For vertical accuracy, this
standard is met if at least 90 percent of well-defined points tested are within one-half contour interval of the correct value.
Elevations of water surface printed on the published map meet this standard; the contour intervals of the maps vary. These
elevations were transcribed into the digital data; the accuracy of this transcription was checked by visual comparison between
the data and the map. For more information, see the National Hydrography Dataset Concepts and Contents document (February
2000) available at <http://nhd.usgs.gov/chapter1/index.html>.
Completeness Commission
evaluation Method Description
Not presently available
Completeness Omission
evaluation Method Description
Not presently available
notes: This metadata was automatically generated from the FGDC Content Standards for Digital Geospatial Metadata standard (version
FGDC-STD-001-1998) using the 2012-06-20T17:21:00 version of the FGDC RSE to ISO 19115-2 transform.
Metadata contact
-
pointOfContact
individual Name Brianna Knoppow
organisation Name
U.S. Environmental Protection Agency, Office of Water