The Missouri Department of Natural Resources (MoDNR) defines a brownfield as “real property, the expansion, redevelopment or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant or contaminant.” (MoDNR 2017e) Almost all cities have them: old gas stations, dry cleaners, old manufacturing buildings, grain silos, and other types of buildings. They may be contaminated with petroleum, dry cleaning fluid (tetrachloroethylene), lead, and/or other chemicals. While the contamination may be limited in scope and scale, presenting little threat to overall public health, it may be sufficient to make the property unusable, leaving cities with abandoned, unusable eyesores that hinder the economic welfare of the community.
Figure 1. Source: MoDNR E-START Map, 2017d.
In 1994, the State of Missouri established a Brownfield/Voluntary Cleanup Program to assist property owners who “want their properties cleaned up to standards acceptable to the state, and to receive some type of certification of the cleanup from the department.” (MoDNR 2017c) If contaminated material is stored onsite at the property, the site enters long-term stewardship. The Department maintains a database of brownfield assessment sites listing 1,122 sites, their location, and their assessment status. Figure 1, created using the DNR’s E-START map utility, shows the locations of the assessment sites.
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Figure 2. Data source: MoDNR 2017a.
Figure 2 shows the number of sites by assessment type. During a Phase I assessment the Department does a records review, observes the physical setting and building characteristics, interviews owners, occupants and adjacent property owners, and reviews historical data concerning the property. If the Phase I reviews turns up any “recognized environmental concerns,” then a Phase II assessment will be conducted, in which the Department may sample and test soil, sediment, groundwater, surface water, drums and other containers, tanks, and/or building materials (asbestos and lead). (MoDNR 2017b)
St. Louis County has the most properties in the database (342), while the City of St. Louis has the second most (242). Jackson County (the location of Kansas City) and Greene County (the location of Springfield) have far fewer (49 and 17, respectively). Does this mean that St. Louis and St. Louis County are that much more contaminated than Kansas City or Springfield? Possibly, as St. Louis once had a large industrial economy, but it may also mean that the St. Louis region has a more active program to identify brownfield sites. (MoDNR 2017a)
The Department provides participants in the program with a report describing the remediation that would be required to return the property to a condition that meets state standards. Unless the property is so contaminated that it qualifies for some other program (Superfund, for instance) remediation is not required, it is voluntary and conducted by the property owner. One a property is brought into compliance with state standards, a certificate of completed cleanup is issued, but it is not deleted from the database of brownfield sites.
Sources:
Missouri Department of Natural Resources. 2017a. Brownfield Assessment List – 2017. Downloaded 10/31/2017 from http://dnr.mo.gov/env/hwp/bvcp/SiteSpecificData.htm.
Missouri Department of Natural Resources. 2017b.Brownfield Assessment/Environmental Site Assessment. Viewed online 11/1/2017 at https://dnr.mo.gov/env/hwp/bvcp/BrownfieldAssessment.htm.
Missouri Department of Natural Resources. 2017c. Brownfields/Voluntary Cleanup Program. Viewed online 10/31/2017 at http://dnr.mo.gov/env/hwp/bvcp/hwpvcp.htm.
Missouri Department of Natural Resources. 2017d. Missouri E-START Map (Brownfields). Downloaded 10/31/2017 from http://www.dnr.mo.gov/ESTARTMAP/map/init_map.action.
Missouri Department of Natural Resources. 2017e. What Is a Brownfield? Viewed online 10/31/2017 at http://dnr.mo.gov/env/hwp/bvcp/Whatisabrownfield.htm.
MoGreenStats 
[…] Brownfield sites represent smaller properties. Though the contamination on them may be sufficient to prevent continued use of the property, it is generally not sufficiently large to represent a threat to the general public health. An example would be a site used as a dry cleaning establishment that became contaminated with dry cleaning fluid (trichloroethylene). Sites contaminated with lead paint or asbestos would be other examples. Because they are unusable, they tend to sit abandoned, forming eyesores and economic drains on the communities in which they are located. Owners are not required to register brownfield properties. Rather, there is a voluntary program for owners who want to remediate their property to state standards and receive a letter certifying the cleanup, enabling the properties to be sold and redeveloped. In total, 1,102 properties are participating in this program or have done so. Some 633 of them were assessed as having no reason to suspect environmental contamination, while the remaining 469 underwent further testing/cleanup. The sites are widely scattered across the state, but tend to concentrate in cities. […]