FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION
VERSION 2006
TITLE: PESTICIDE DRASTIC VULNERABILITY AREAS OF THE INTERMEDIATE AQUIFER SYSTEM
Geodataset Name: APPSIT Geodataset Type: SHAPE Geodataset Feature: POLYGON
GENERAL DESCRIPTION:
This dataset contains statewide DRASTIC data for the Intermediate Aquifer System recalibrated for pesticide use. DRASTIC is a system developed jointly by the U.S. Environmental Protection Agency (USEPA) and the National Water Well Association (NWWA) to map potential aquifer vulnerability to pollution (in this case, resulting from pesticide use) introduced on the ground's surface.
DATA SOURCE(S): Florida Department of Environmental
Protection (FDEP)
SCALE OF ORIGINAL SOURCE MAPS: 1:100,000 except for Alachua County
(which was mapped at 1:24,000)
DATE OF AUTOMATION OR SOURCE: Source 1999
GEODATASET EXTENT: State of Florida
FEATURE ATTRIBUTE TABLES:
Datafile Name:AQPSIT.DBF ITEM NAME WIDTH TYPE PRECISION AREA 18 DECIMAL 5 PERIMETER 18 DECIMAL 5 AQPSIT# 5 DECIMAL - AQPSIT-ID 5 DECIMAL - SETTING 3 CHARACTER - DW 6 DECIMAL - NR 6 DECIMAL - AM 6 DECIMAL - SM 6 DECIMAL - T 6 DECIMAL - IV 6 DECIMAL - HC 6 DECIMAL - DWV 6 DECIMAL - NRV 6 DECIMAL - AMV 6 DECIMAL - SMV 6 DECIMAL - TV 6 DECIMAL - IVV 6 DECIMAL - HCV 6 DECIMAL - INDEX_X 6 DECIMAL - DESCRIPT 64 CHARACTER -
FEATURE ATTRIBUTE TABLES CODES AND VALUES:
item item description (DRASTIC parameter item value multiplied by weight= weighted score item) DW Depth to water x 5 = DMV NR Net recharge x 4 = NRV AM Aquifer media x 3 = AMV SM Soil media x 5 = SMV T Topography x 3 = TV IV Impact of vadose zone x 4 = IVV HC Hydraulic conductivity x 2 = HCV hydrogeologic setting (not scored) DWV Weighted score of Depth to Water NRV Weighted score for Net Recharge AMV Weighted score for Aquifer media SMV Weighted score for Soil Media TV Weighted score for Topography IVV Weighted score for Impact of Vadose Zone HCV Weighted score for Hydraulic Conductivity INDEX_X INDEX=(DRV+ NRV + AMV + SMV + TV + IVV + HCV) DESCRIPT BASED ON SETTING ITEM FROM ORIGINAL COVERAGE The eighth layer, hydrogeologic setting, reflects general geomorphology and varies nationally by region. Florida lies within region 11, the Southeast Coastal Plain, of the Ground water region of the United States as described by Heath in USGS Water Supply Paper 2242. Four Settings predominate in region 11 and they are: 11A - Karst limestone areas ( limestone near the surface) 11B - Coastal Deposits (thick clastic marine sediments) 11C - Swamps and Wetlands 11D - Beaches and Bars (sandy coastal areas and relict beach ridges)
USER NOTES:
DRASTIC is a system developed jointly by the U.S. Environmental Protection Agency (USEPA) and the National Water Well Association (NWWA) to map potential aquifer vulnerability. The methodology utilizes existing hydrogeological information to produce color-coded maps which display areas that are more or less likely to be affected by pollution introduced on the ground's surface. These maps depict areas which are more or less sensitive to land use changes which may affect ground water quality. Drastic maps are composites made up of eight individually mapped hydrogeological parameters. Seven of these parameters (depth to water - Dw, net recharge - Nr, aquifer media - Am, soil media - Sm, topography - T, impact of the vadose zone - Iv and hydraulic conductivity - Hc) are used to derive the DRASTIC summary index score. The eighth, hydrogeologic setting, is useful for general map interpretation but, it is not included in the summary index. Pesticide DRASTIC is designed to be used where the activity of concern is the application of pesticides to an area. It represents a special case of the DRASTIC Index. The only way in which Pesticide DRASTIC differs from DRASTIC is in the assignment of relative weights for the seven DRASTIC factors. All other parts of the two indexes are identical; the ranges, ratings and instructions for use are the same. If the user is concerned with the ground water pollution potential of an area by pesticides, then the weights for Pesticide DRASTIC should be used. LIMITATIONS OF THE DATA / WARNINGS TO THE USER : Drastic maps are most useful as a generalized tool to assess regional potential aquifer vulnerability. Except for soils and topography layers, the source maps used were regional, water management district or statewide in scale and scope of coverage. This precludes the use of DRASTIC maps as a site-specific tool for assessing potential aquifer vulnerability.
FGDL QUALITY ASSURANCE STATUS:
-Tolerances were changed to FGDL standards. -DESCRIPT item was added based on the item SETTING; SETTING item was dropped -converted dataset from ArcView shapefileform to Arc/Info coverage form using SHAPEARC command
REFERENCES:
DATA LINEAGE SUMMARY:
A separate polygon coverage was built for each parameter and then the eight coverages are composited into a single coverage with all information from the originals for the FASTCAD drawings. These drawings were then converted to ARC/INFO coverages which edited by county. The county coverages were then edgematched and mapjoined into a statewide coverage. The statewide coverages, for each aquifer, were then dissolved for the individual DRASTIC parameters for further error checking of the composite coverages. Once all errors were corrected, the composite attributes were recalculated for the final statewide Pesticide DRASTIC coverages.
MAP PROJECTION PARAMETERS
PROJECTION ALBERS DATUM HPGN UNITS METERS SPHEROID GRS1980 1st standard parallel 24 0 0.000 2nd standard parallel 31 30 0.000 central meridian -84 00 0.000 latitude of projection`s origin 24 0 0.000 false easting (meters) 400000.00000 false northing (meters) 0.00000
DATA SOURCES CONTACT(S):
Name: Florida Department of Environmental Protection Abbr.name: FDEP Phone: 850-414-8550 Web site: http://www.dep.state.fl.us Contact Person: Phone: (850)921-9425, (850)414-8550
FGDL CONTACT:
Name: Florida Geographic Data Library
Abbr. Name: FGDL
Address: Florida Geographic Data Library
431 Architecture Building
PO Box 115706
Gainesville, FL 32611-5706
Web site: http://www.fgdl.org
Contact FGDL:
Technical Support: http://www.fgdl.org/fgdlfeed.html
FGDL Frequently Asked Questions: http://www.fgdl.org/fgdlfaq.html
FGDL Mailing Lists: http://www.fgdl.org/fgdl-l.html
For FGDL Software: http://www.fgdl.org/software.html