Steven H. Douglas
20170828
Attenuation Factor model results for Upper Floridan aquifer vulnerability to Bromacil and Ethylene Dibromide
raster digital data
U.S. Geological Survey Data Release
doi:10.5066/F7S46QTV
St. Petersburg, FL
U.S. Geological Survey
https://doi.org/10.5066/F7S46QTV
This dataset includes Attenuation Factor (AF; Rao and others, 1985) model results for Upper Floridan aquifer vulnerability to Bromacil and 1,2-Dibromoethane or Ethylene Dibromide (EDB). The AF value serves as an index for assessing the transport of pesticide mass from the vadose zone. The AF model setup requires the input of raster soil bulk density, soil organic carbon content, soil field capacity, soil air filled porosity, recharge to the aquifer, depth to groundwater, the pesticide sorption coefficient, pesticide Henry's Law Constant, and pesticide half-life. These variables were entered into the AF equation using the raster calculator tool in ArcGIS. The resulting AF values are dimensionless and range between 0 and 1. A value of 1 indicates that all of the pesticides in the vadose zone will leach into the groundwater; conversely, a value of 0 suggests that no pesticides will leach into the groundwater.
This dataset was generated from the Attenuation Factor model to test the model's ability to indicate groundwater vulnerability to pesticides in the Southwest Florida Water Management District (SWFWMD).
A downloadable version of the final dataset is provided in GeoTIFF file format with 10-meter resolution.
2017
publication date
None planned
-83.252177
-80.829948
29.695895
26.572896
USGS Metadata Identifier
USGS:38dabaf9-3264-4b63-802d-2f63dabc8d20
None
Attenuation Factor
pesticide
aquifer
raster dataset
Florida
Southwest Florida Water Management District
U.S. Geological Survey
USGS
University of South Florida St. Petersburg
ISO 19115 Topic Category
geoscientificInformation
inlandWaters
environment
health
USGS Thesaurus
geology
groundwater
water quality
water resources
hydrogeology
None
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
Cherokee Nation Technologies contracted to the U.S. Geological Survey
Steven H. Douglas
physical and mailing address
600 4th St S
St. Petersburg
FL
33701
727-502-8134
sdouglas@usgs.gov
U.S. Geological Survey and University of South Florida St. Petersburg
Microsoft Windows 7 Version 6.1 (Build 7601) Service pack 1; Esri ArcGIS 10.2
Rao, P.S.C., Hornsby, A.G., and Jesup, R.E.
1985
Indices for ranking the potential for pesticide contamination of groundwater
44, 1-8
Florida
Proceedings of the Soil and Crop Science Society of Florida
Douglas, S., Dixon, B., and Griffin, D.
Unknown
Assessing intrinsic and specific vulnerability models ability to indicate groundwater vulnerability to groups of similar pesticides: a comparative study
Philadelphia, PA
Physical Geography
No formal attribute accuracy tests were conducted.
Raster values were checked for consistency with expected values.
Data-set is considered complete for the information presented, as described in the abstract.
No formal horizontal positional accuracy tests were conducted.
A formal accuracy assessment of the vertical positional information in the data-set has either not been conducted, or is not applicable.
Southwest Florida Water Management District
20090206
District Polygon Boundary
vector digital data
Brooksville, FL
Southwest Florida Water Management District
http://data-swfwmd.opendata.arcgis.com/datasets/c785f7ae47d94a4ab0a41c0e9c50dcc0_13
digital
20090206
publication date
DISTRICT
Water management district boundaries dataset was used as the study area extent that the other layers were clipped to.
U.S. Geological Survey
20111117
Potentiometric Surface of the Upper Floridan Aquifer in Florida and in Parts of Georgia, South Carolina, and Alabama, May – June 2010
vector digital data
Orlando, FL
U.S. Geological Survey
https://pubs.usgs.gov/sim/3182/data/Potmap_wells_May2010.zip
digital
201005
201006
ground condition
SIM3182
This vector point file of potentiometric surface was interpolated to calculate the depth to groundwater variable in the Attenuation Factor model equation.
Florida Geographic Data Library
201301
Florida Digital Elevation Model (DEM) Mosaic - 5-Meter Cell Size - Elevation Units Meters (FGDC)
vector digital data
Gainesville, FL
University of Florida GeoPlan Center
ftp://ftp.fgdl.org/pub/state/flidar_mosaic_ft.zip
digital
201301
publication date
FLIDAR_MOSAIC_M
The 5-meter DEM was used as the input surface elevation that was used to create the depth to groundwater variable.
Mapping and GIS Section, Southwest Florida Water Management District
2002
Aquifer Recharge/Discharge data from USGS 2002 Model
vector digital data
2379 Broad Street, Brooksville, FL 34604-6899
Southwest Florida Water Management District
http://ftp.swfwmd.state.fl.us/pub/gisdata/physical_sparse/recharge2002.exe
digital
199308
199407
ground condition
SWFWMD
Aquifer recharge/discharge was used as the recharge variable in the Attenuation Factor model equation.
Mackay, D., Shiu, W.Y., Ma, K.C., and Lee, S.C.
20060314
Handbook of Physical-Chemical Properties and Environmental Fate for Organic Chemicals Volume II, Second Edition
print
2006
publication date
Pesticide Half-Life (t1/2)
The half-life of EDB in groundwater was used as the half-life variable in the Attenuation Factor model equation.
Staudinger, J., and Roberts, P.V.
20010626
A critical compilation of Henry's law constant temperature dependence relations for organic compounds in dilute aqueous solutions.
44(4)
https://doi.org/10.1016/S0045-6535(00)00505-1
digital
1953
1999
publication date
Henry's Constant (Kh)
The EDB Henry's law constant was used as the Henry's law constant variable in the Attenuation Factor model equation.
Delle Site, A.
2001
Factors affecting sorption of organic compounds in natural sorbent/water systems and sorption coefficients for selected pollutants. A review.
30(1)
print
1964
1992
publication date
Sorption Coefficient (Koc)
The EDB sorption coefficient was used as the sorption coefficient of pesticides on organic matter variable in the Attenuation Factor model equation.
U.S. Department of Agriculture, Natural Resources Conservation Service
2015
USDA-NRCS Soil Survey Geographic (SSURGO 2.2): Bulk Density, Organic Carbon Content, Field Capacity, and Porosity
vector digital data
Fort Worth, TX
USDA/NRCS - National Geospatial Center of Excellence
https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/geo/?cid=nrcs142p2_053627
digital
2015
ground condition
SSURGO
Bulk density (BD), Organic Carbon Content (OC), Field Capacity (FC), and Porosity (AC) were used as variables in the Attenuation Factor model equation
Tabular and map Soil Survey Geographic Database SSURGO data for Florida were downloaded through the U.S. Department of Agriculture (USDA) Geospatial Data Gateway. Descriptions for the SSURGO classes are available at the Soil Survey website http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054253. SSURGO metadata is available at: http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/home/?cid=nrcs142p2_053631. The polygon shapefiles were joined to the tabular files within the SSURGO file geodatabase. The first join to be made uses the “mukey” field as the common identifier to join the cokey field from the “component” table. The second join to be made uses the cokey field as the common identifier to join the om_r (organic carbon content), dbthirdbar_r (bulk density), awc_r (field capacity), and wsatiated_r (porosity) field from the “CHorizon” table. The Florida shapefiles were clipped to the SWFWMD boundaries, using the clip tool in ArcGIS and the polygon shapefile, DISTRICT, as the boundary. The variables are expressed as a percent or fraction of the total volume. If the original data from SSURGO is expressed as floating-point decimal values between 0 and 1 then they were converted to values between 1 and 100 by adding a new field to the raster in the attribute table and using the field calculator to multiply the original values by 100. Bulk density was converted from g/cm3 to kg/m3 using the field calculator and by multiplying the bulk density values by 1000. The final polygon shapefile was converted to 10 meter raster GeoTiffs using the Polygon to Raster tool and selecting the new field with values 1 to 100 as the new raster values.
2015
Steven H. Douglas
Cherokee Nation Technologies contracted to the U.S. Geological Survey
Physical and mailing
600 4th St S
St Petersburg
FL
33701
727-502-8134
sdouglas@usgs.gov
Depth to groundwater was created by clipping the USGS potentiometric well points shapefile (Kinnaman and Dixon, 2011) to the SWFWMD study area extent. The potentiometric surface was calculated by interpolating the points with the Inverse Distance Weighted tool in ArcGIS and using the default settings. Finally, depth to groundwater was created by subtracting the potentiometric surface from the FLIDAR_MOSAIC_M DEM value using the raster calculator tool.
2015
Henry's law constant, half-life, and sorption coefficient raster layers were created by making three copies of the bulk density raster from the SSURGO data-set. Using the ArcGIS field calculator the values for all cells in the study area were changed to the corresponding variable value to create the constant raster variable.
2015
The recharge polygon shapefile, SWFWMD, was converted to a 10-meter raster GeoTiff, using the Polygon to Raster tool in ArcGIS.
2015
The Attenuation Factor model equation described by Rao and others (1985), was constructed using the Raster Calculator tool in ArcMap. The resulting AF values range between 0 and 1 and were divided into 5 classes, using the reclassify tool in ArcGIS, based on the standard deviation: very low (less than 0.3), low (between 0.3 and 0.522), medium (between 0.522 and 0.742), high (between 0.742 and 0.962), and very high (greater than or equal to 0.962).
2015
Added keywords section with USGS persistent identifier as theme keyword.
20201013
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Raster
Grid Cell
19397
32005
USA_Contiguous_Albers_Equal_Area_Conic_USGS_version
29.5
45.5
-96.0
23.0
0.0
0.0
row and column
10.0
10.0
meters
North American Datum of 1983
Geodetic Reference System 1980
6378137.0
298.257222101
af_model.tif
GeoTIFF file that includes attenuation factor model results for the Upper Floridan aquifer vulnerability to Bromacil and 1,2-Dibromoethane or Ethylene Dibromide (EDB).
USGS
OID
Internal feature number. Sequential unique whole numbers that are automatically generated.
Esri
0
4
Value
AF reclassified vulnerability class values. 1 = Very Low Vulnerability, 2 = Low, 3 = Medium, 4 = High, 5 = Very High.
USGS
1
Very Low Vulnerability
USGS
2
Low Vulnerability
USGS
3
Medium Vulnerability
USGS
4
High Vulnerability
USGS
5
Very High Vulnerability
USGS
Count
Number of cells
Esri
25309776
73913452
Cherokee Nation Technologies contracted to the U.S. Geological Survey
Steven Douglas
physical and mailing
600 4th St S
St Petersburg
FL
33701
727-502-8134
sdouglas@usgs.gov
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The data have been approved for release and publication by the U.S. Geological Survey (USGS). Although the data have been subjected to rigorous review and are substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, the data are released on the condition that neither the USGS nor the U.S. Government may be held liable for any damages resulting from authorized or unauthorized use. Although the data have been processed successfully on a computer system at the USGS, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS shall not be held liable for improper or incorrect use of the data described and/or contained herein. Users of the data are advised to read all metadata and associated documentation thoroughly to understand appropriate use and data limitations.
GeoTIFF
2017
https://coastal.er.usgs.gov/data-release/doi-F7S46QTV/data/AF_model.zip
None.
20201013
Cherokee Nation Technologies contracted to the U.S. Geological Survey
Steven H. Douglas
physical and mailing
600 4th St S
St. Petersburg
FL
33701
727-502-8134
sdouglas@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time