Index polygons of pollution potential. Based on an ERDAS study that utilized seven layers of spatial data to build an index value of the potential for groundwater pollution from a surface contaminant. The seven layers are (D)epth to water, (R)echarge rate, (A)quifer characteristics, (S)oils, (T)opography, (I)mpact of vadose zone and hydraulic (C)onductivity. The layers can be weighted differently by different researchers but this index is the published map from CSD.
Summarize the impact of surface contaminants to groundwater contamination by applying the DRASTIC model.
ground condition
None, but the following should be included in citations: "The Conservation and Survey Division has produced this product using what is thought to be the most reliable information available or reproduced the material as provided. The detail and precision of the interpretations made are according to accepted professional standards and are dependant upon the techniques, hardware, and/or software utilized."
301 Centennial Mall South, P.O. Box 94676
The original science was done using a raster-based image processor (ERDAS). The input layers were from several sources, all based on 1x2 degree topographic sheets. This data had a cell-size of about 100 meters, and is suitable for generalized planning not site-specific decisions. The ArcInfo command LATTICEPOLY was used to create this dataset.
Edgematched and adjusted as needed.
Coverage is state-wide & updates are not planned
none
ERDAS was used to subset the data into 1x1 degree blocks in SVF format. Each block was converted to an ARC lattice using the ERDASSVF command. The several lattices were merged together, converted to polygons and projected to the CSD standard projection.
301 Centanninal Mall South, P.O. Box 94676
Metadata imported.
Internal feature number.
ESRI
Feature geometry.
ESRI
Area of feature in internal units squared.
ESRI
Perimeter of feature in internal units.
ESRI
Index of pollution potential
CSD
Polygons labeled by index value
Separate index values for each layer were decided. A composite index was determined, and reclassified to eight values. This data is converted from the original raster-based product.
301 Centennial Mall South, P.O. Box 94676
none
Spatial and attribute information
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Written request, billed as Time & Materials
301 Centennial Mall South, P.O. Box 94676