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GIS 301 - Skyline College - Forsberg

Assignment 4:
Using Census Data in Assessing children's risk of exposure to lead.

Scenario: You are conducting a survey in the community to assess the children's risk of exposure to lead. Because of a very limited budget, you are only able to conduct a few dozen home visits. That is why you must look at demographic data to pinpoint the most likely places to begin field research of children's risk of exposure to lead.

The two main sources of lead in the urban environment are lead in gasoline which contaminated soils near roads and highways, and lead in paint which is common in older housing.

Data related to children's lead exposure:

In this assignment you will use GIS methods of buffering and overlay to analyze maps of census data. Think about what combination of factors in an area would make it a likely candidate for further investigation. That is, where is it most likely that children are being poisoned by lead? You will want to look for an overlap between those areas with a lot of children and minorities, with a lot of poor people and renters, and with a lot of older housing located near highways.

Getting more data:

Data for this project was acquired online using primarily the U.S. Census Bureau's 1990 data
1990 Census Lookup - by zip
Statistical Resources on the Web Demographics and Housing - census data
U.S. Census Bureau's TIGER Mapping Service "Coast to Coast" Digital Map Database - TMS Version 2.5
Additional detailed base maps with street names can be accessed using - maps

Mapping leaded gasoline contamination
Find the major highways and arterials more than ten years old and draw a buffer of one quarter mile on either side of the road. This indicates the areas most likely to have been contaminated by leaded gasoline exhaust coming from traffic.

Finding older housing with leaded paint
Choose a specific place or community in the United States that you would like to research. Look up a map of the zip codes for the area in the yellow pages. Using the 1990 Census Lookup - by zip Look up the "year structure built" census data for each zip code and calculate the percentage of housing units built before 1950. Pick one or two adjoining zip codes where at least 27% of the housing was built before 1950. This will be the area of analysis. For more information, read "Lead Inform" On the ground . . . You may also choose a zip code based on its proximity to highways and major arterials.

Presentation of findings:

You will present your research results pinpointing the most likely places to begin field research of children's risk of exposure to lead in your research area. Your presentation could include analysis methodology, research questions, critiques of the data categories or levels of resolution, and a summary of what you learned. Please spell out exactly how you arrived at your conclusions.

Related links:

Dumbing Down the Children--Part 1, Part 2, Part 3

Lead Inform - On the ground . . .

Statistical Resources on the Web Demographics and Housing - census data

The Frequently Asked Questions about the TMS Version 2.5 are very helpful