HazMatMapper: an online and interactive geographic visualization tool for exploring transnational flows of hazardous waste and environmental justice

Figures & data

Figure 1. HazMatMapper in action: (a) central map; (b) configuration controls; (c) advanced context controls; and (d) information panel.

Figure 2. Sample RCRA manifest. Information coded into the spatial database is highlighted. Personal information is screened.

Table 1. Uncertainties in the hazardous waste dataset.

Uncertainties data can be	Example	Solution
Inconsistent	Company names spelled differently, e.g. AIR PRODUCTS & CHEMICALS and AIR PRODUCTS & CHEMICALS, INC	Standardize spellings in spreadsheet
Ambiguous	Some waste described differently and listed under different categories but appearing to be the exact same thing, e.g.
	WASTE CORROSIVE LIQUIDS, N.O.S. (SODIUM HYDROXIDE) – UN1760 WASTE CORROSIVE LIQUID, BASIC, INORGANIC, N.O.S. (SODIUM HYDROXIDE) – UN3266 WASTE CAUSTIC ALKALI LIQUIDS, N.O.S. (SODIUM HYDROXIDE) – UN1719	Use small multiples to indicate differences when waste types are more or less aggregated or differently classified
Missing	Some manifests are missing information, e.g. expected management method	Map amount of waste that has no management method listed

Note: In addition to implementing local fixes for inconsistent data, we have captured these uncertainties as additional facets for mapping in future work.

Figure 3. EPA regions.

Figure 4. Using HazMatMapper through the four different interface controls: (a) proportional symbols of waste sites are the default view on the central map; (b) clicking on a site draws flow lines between exporters and importers; (c) accessing the configuration controls allows users to draw choropleths of waste imports binned by state; (d) users overlay poverty statistics through the advanced context controls; (e) clicking on a site retrieves further EJ-relevant site data in an information panel; (f) selecting ‘manifests’ in the informational panel lets the user download copies of the site’s waste trade forms.

Figure 5. Users can filter the map, shading it by waste processing types. Investigating the kinds of waste disposal methods for EPA Region 6, the user might first shade the map by the sites planning to process waste under the code ‘H040,’ which indicates ‘Incineration’.