[Note: The full report filed for the grant-funded portion of this work appears on this site at: http://brianaltonenmph.com/3-gis-environmental-health/report-for-grant-funded-research-2002/]
Four Sectors defined for the Portland, Oregon Area in order to evaluate cancer prevalence relative to population density and exposure site locations.
Upon initial inspection of the data for the release sites, it was apparent that there was a northwest sector largely responsible for much of the commerce industry related to supplying the region with the majority of its necessary commodities. This region was also devoted primarily to other shipping and railroad industries, including the transport of chemicals. This region also contained a large number of bulk fuel storage facilities and several major chemical storage sites for the region, including several devoted to chemical manufacturing (i.e. Sulfuric Acid production). These historical and landuse facts in association with recent news and EPA events related to superfund site consideration, this northwest sector of the immediate metropolitan region was defined as its own unique exposure site, with the potential for exposure related to nearly 270 degrees of release sites history.
From this initial review, it was easy to next identify the second potential high risk region–another multiple superfund site region (i.e. an Aluminum manufacturing facility and a contaminated watershed. The two remaining areas in the Portland tri-city region, contained in the oval urban are boundary established, formed the final two research areas to be compared with the initial two major superfund- and toxic release history defined sites.
Case distribution in the Portland, Oregon Area. The application of Thiessen Polygons to depict results in toxic release sites impacts on population health.
The distribution of toxic release sites in the Portland area. Based on a Theissen Polygon review of cancer case distribution in relation to multiple sites exposure.
It is important to note here that the demographics and economics of each of these four sectors are quite different from each other. As already noted, the northwest sector, where most of the release sites are, is also where some of the poorest populations in the metro area reside according to census data. In contrast, the southwest sector, which consists of numerous cinder cone formation, montane/hillside housing settings, and former-agricultural-settings-turned-suburban-sprawl, is rich mostly in high income families, but also a signficant number of middle and lower income groups depending upon the location (the closer to central downtown you are in the heavily forested cinder cones setting, the more expensive the property is). The southeast sector is traditional middle and lower class for the most part. The northeast sector, traveling along the south shores of the Columbia River, is very similar economically, but also has some important industrial sites. It lacks the necessary much larger boat piers and landings found in the Northwest sector, and so has a very low number of highly risk, superfund applicant or superfund sites to be reviewed. However, it is important to note that both the northeast and southeast sectors are important settings economically for both small and middle-sized businesses, including industrial facilities.
So, although these two eastern sectors lack most of the worst sites documented in the state, they still have important toxic features that must be considered, mostly due to the urban-sprawl that has been happening here. This economic growth of the Portland outskirts has enabled larger businesses to set up throughout these two sectors. This ultiamtely makes the toxic release site density for these two parts of the Metro Region fairly significant, if we include confirmed release and other toxic release sites histories into these two area’s evaluations. For the northeastern sector in fact, this in part why the Multnomah groundwater site Superfund site was finally established. A review of the history of this site demonstrates just how politically sensitive such a formal national move for the state could be. Politically speaking, there were several (perhaps more) companies responsible for polluting this area, rather than lay the blame on just one or a few of these companies and call it the “FITB business(es) site”, the watershed itself and groundwater were used to spatially define the toxic region. This way the entire groundwater area could be cleaned up, without laying blame on a particular company or small business by including its name in the release site title.