Search 5,000,000+ questions and answers.

Frequently Asked Questions

How accurate are TRI locations in TOXMAP?

TOXMAP - Frequently Asked Questions
TOXMAP plots the location of most TRI facilities and Superfund sites using addresses and coordinates from the EPA Facility Registry System (FRS) (http://www.epa.gov/frs). The location of some of these may appear to be slightly inaccurate, because they are calculated by an estimation process.
Related Questions

What TRI chemicals are mapped in TOXMAP?

TOXMAP - Frequently Asked Questions
TOXMAP maps the Toxics Release Inventory (TRI) chemicals reported to the Environmental Protection Agency (EPA), as required by the Emergency Planning and Community Right to Know Act (EPCRA). TOXMAP uses the most current TRI data available from the EPA. Data submission deadlines, data entry processes, and data quality control and review all influence the actual date of data release both by the EPA and by TOXMAP.
Related Questions

How current is the TRI data that TOXMAP uses?

TOXMAP - Frequently Asked Questions
TOXMAP uses the most current TRI data available from the EPA. 1987 is the first reporting year of the TRI program. Data submission deadlines, data entry processes, and data quality control and review all influence the actual date of data release. A complete list of chemicals currently listed in TOXMAP TRI can be found at http://toxmap.nlm.nih.gov/toxmap/main/chemicals.jsp. A complete list of TRI chemicals required to be reported to the EPA can be found at http://www.epa.gov/tri/chemical/index.
Related Questions

Why are the locations of some TOXMAP facilities/sites slightly inaccurate?

TOXMAP - Frequently Asked Questions
TOXMAP facility locations are calculated by an estimation process that relies on "geocoding." Geocoding is a method that assigns a latitude and a longitude to an address. Even the most accurate latitude/longitude coordinate calculations, including those used by TOXMAP, are estimates; this can account for minor inaccuracies in site locations on a map.
Related Questions

How accurate is TRI data?

TOXMAP - Frequently Asked Questions
The EPA's Toxics Release Inventory (TRI) Program is a national database that identifies facilities, chemicals manufactured, processed and used at the identified facilities, annual amounts of chemicals released and otherwise managed (on and off site) in waste.
Related Questions

What is TOXMAP?

TOXMAP - Frequently Asked Questions
TOXMAP (http://toxmap.nlm.nih.gov) is a Geographic Information System (GIS) from the Division of Specialized Information Services (http://sis.nlm.nih.gov) of the U.S. National Library of Medicine (NLM) (http://www.nlm.nih.gov) that uses maps of the United States to help users visually explore data from the U.S. Environmental Protection Agency (EPA)'s Toxics Release Inventory (TRI) and Superfund Program.
Related Questions

WHO IS TRI?

Frequently Asked Questions
TRI stands for Trisomy 21 Research Foundation, Inc., a non-profit organization founded by Dr. Lawrence Leichtman to further investigate TNI as a therapeutic treatment for patients with Down syndrome and encourage further research.
Related Questions

How accurate are the geographic locations?

Land Cover for Wyoming
The minimum mapping unit for upland cover types is 100 ha and 40 ha for water/riparian types, a level of generalization that was not intended to accurately portray accurate positional boundaries of vegetation. Polygons generally portray more than one cover type (primary, secondary and other), the actual boundaries between the different types being at too fine a scale to be captured at the the specified minimum mapping unit.
Related Questions

Lee Stocking Island, Bahamas Sea Surface Temperature Time Se...
Users are referred to online documentation at <http://podaac.jpl.nasa.gov/cgi-bin/dcatalog/fam_summary.pl?sst+pfsst>
Related Questions

AERIAL PHOTOS (2003) (SDE_ADMIN.AERIAL_PHOTOS_2003)
This map complies with National Map accuracy Standards. The source aerial photography scale is 1:7200, thus 90% of locations tested must fall within 1/30 inch at final map scale. The source aerial photography supports mapping at scales of 1:1200 (1" = 100') or smaller. NMAS for 1:1200 scale is 3.33 feet.
Related Questions

Generalized Geologic Map of the Conterminous United States
The accuracy of the original data was checked by comparing the digital files to several data sources. Both the line work and the polygon labels were checked against the source compilation.
Related Questions

Razor clam habitat areas for MESA - Vol. 1
Arc data were digitized from inked mylar maps registered to 1;250,000 USGS base maps. Coastal hydrography were used primarily from ADNR hydrography and USGS DLGs. Verification of data consisted of paper plots checked against the original mylar maps. No accuracy assessment has been performed against real world positions.
Related Questions

LiDAR Digital Ground Model Contour Isolines
The contours were generated from ArcInfo lattice grids based on 6-foot center to center posting. Horizontal accuracy will be approximately 1/2 of the posting distance or about 3 feet in areas where point density is high (equivalent to 5-7 feet point spacing). Where point density is considerably reduced due to poorer to-ground penetration rates, the horizontal accuracy will be reduced proportionally and may be only accurate to 10-15 feet and locally accuracy will be even poorer.
Related Questions

Predicted Terrestrial Vertebrate Species Distributions for W...
Does not apply since this dataset is a model and because of the generalization of the source datasets used to generate this coverage.
Related Questions

Mineral Resources Data System
Positional information is highly variable. In the best cases this information was provided by plotting the location on a 7.5 minute topographic map, however many records were located on the basis of published reports containing imprecise or scant information on the specific geographic location.
Related Questions

ALLUS80K: Medium Resolution Digital Vector U.S. Shoreline sh...
The data supplied here are a compilation of information collected from some 270+ current or pre-release National Ocean Service Navigation Charts. In compiling this product we made no attempt to ascertain the congruency between the charted data, and the real world. Our objective was to simply capture the representative coastline as provided to us via the NOS Chart.
Related Questions

LiDAR Digital Ground Model (DGM) Elevation
See the Puget Sound LiDAR Consortium website for details regarding the accuracy of the data from that project, <http://duff.geology.washington.edu/data/raster/lidar/>. The laser produced an approximately 0.9 meter ground spot (footprint). Horizontal accuracy is generally interpreted to be approximately two times the laser footprint, resulting in a horizontal accuracy estimate of about 1.8 meters. For the King County/3di data, horizontal accuracy specification is 1 meter RMSE.
Related Questions

CANADA: Eastern Canadian Provinces
The positional accuracy ranges from sub-meter (GPS derived) to 5 meters (1:50,000 National Topographic Data Base (NTDB) areas) .
Related Questions

Preliminary geologic map of the northeast Dillingham quadran...
Users of this digital data set should respect the intentions of the original mappers and the limitations of a thematic map. This geologic map compilation is intended to be used at a scale of 1:100,000; it is not intended to be used at a significantly more detailed scale.
Related Questions

Glovers, Belize Sea Surface Temperature and Degree Heating W...
Users are referred to the following guide. Goodrum G., K. B. Kidwell, and W. Winston, 2000, NOAA KLM USER'S GUIDE. U.S. Department of Commerce, National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service, National Climatic Data Center, Climate Services Division, Satellite Services Branch, FOB3, Room G227, E/CC33, 5200 Auth Road, Suitland, MD 20746-4304, USA. This manual is available on line at <http://www2.ncdc.noaa.gov/docs/klm/cover.
Related Questions

Preliminary geologic map of the Chugach National Forest spec...
Users of this digital geologic map should respect the intentions of the original mappers and the limitations of the map. This geologic map is intended to be used at a scale of 1:63,360; it is not intended to be used at a more detailed scale.
Related Questions

Extent of Pleistocene Lakes in the Western Great Basin
The lake shoreline locations are delineated using contour lines derived from DEM source data with 3 arc-second (nominally 90 meters) grid cell resolution. Horizontal accuracy of DEM data is dependent upon the horizontal spacing of the elevation matrix. Within a standard DEM, most terrain features are generalized by being reduced to grid nodes spaced at regular intersections in the horizontal plane.
Related Questions

ACMP Coastal District Boundaries
The boundary placement has been compiled to be accurate for use at a 1:250,000-scale. Accuracy of these boundaries portrayed at larger scales can not be assured.
Related Questions

Monthly average polar sea-ice concentration
The grids provided in the source data (supplied by NSIDC) are described in the user's guides of the relevant products, and the positional accuracy of the pixels is dealt with both in the user's guides and in the NASA report on the SMMR data.
Related Questions

s Mosaic of Aerial Photography of the Salt River Bay Nationa...
Fixed ground control points were selected through examination of imagery, and located in the field. GPS data was collected at each point, and approximately 10-15 points were utilized to orthorectify the imagery. Several additional points were subsequently used to calculate horizontal accuracy:
Related Questions

How accurate are class 0 locations?

CLS : Argos general - FAQ
Error estimation of class 0 location is higher than 1.5 km. The error estimate (radius) for a Class 0 location is greater than 1500m and there is no upper limit - the error could be 50, 100, 500 km. Locations with errors less than say 10 km (usually the platform is close to the satellite ground track or random frequency instabilities are observed between messages), Very inaccurate locations, with errors above 50 km, which correspond to out-of-range instabilities from the oscillator.
Related Questions

North American Atlas - Roads
Positional accuracy varies throughout the data. Positions are dependent on the accuracy of the source data and on the result of the generalization and integration processes. Data for areas outside of Canada, Mexico, and the United States of America are only provided for context; Natural Resources Canada, Instituto Nacional de Estadística Geografía e Informática, and the U.S.
Related Questions

Geology of the Conterminous United States at 1:2,500,000 Sca...
The users of the geologic map on this disc should respect the intentions of the compilers of the map and some of its limitations. The Geologic Map of the United States (King and Beikman, 1974b) is intended to be used at a scale of 1:2,500,000; it is not intended to be used at a more detailed scale. For instance, Colorado is about 10 inches wide at the published scale of the King and Beikman map.
Related Questions

Got A Question? Ask Our Community!


More Questions >>

© Copyright 2007-2008 QueryCAT
About • Webmasters • Contact