Assessing Outdoor Air Near Schools
Jefferson Elementary School - Gary, IN
- Understanding the Monitoring Data
- Initial Sample Results
- Initial Analysis
- Additional Sample Results
- Final Analysis
EPA selected this school for monitoring because it is located near a coke oven and steel manufacturing facility that are sources of air toxics emissions. The initial monitoring identified elevated concentrations of one key pollutant – manganese – that warranted additional monitoring at this school. We decided to conduct the additional monitoring at Gary-4th Ave./ Railcats which is closer to the potential manganese source. We reported concentrations of this key pollutant for this location in the table below. While manganese is the key pollutant at these monitoring sites, other metals (such as arsenic) were also measured.
About the Data
The table below shows the levels of the key pollutant in air samples collected at the monitoring site beginning in September 2010. The table also includes individual “sample screening levels” for the key pollutant monitored at each location. EPA developed these screening levels for this project to help the Agency and the community get an early sense of what the data are showing. The sample screening level is a level of pollution in the air that is below what we expect to cause health problems from short-term exposures – all day, every day over a period ranging up to at least a couple of weeks (longer, for some pollutants). These screening levels are used only as guidelines for this project.
About The Table
Compare the sample results to the short-term screening level at the top of the table. Numbers at or below that level indicate the pollutant is not likely to pose immediate health concerns.
To use the screening level, compare it to each sample result:
- a sample result at or below the sample screening level is not a concern for risk of health problems from short-term exposures.
- a sample result above the screening level does not mean that there is a risk to children and adults at the school. It is a signal for EPA to further evaluate those and subsequent results for that pollutant.
EPA analyzed the potential for health concerns from long-term exposure. This analysis can be found under the Final Analysis tab. Monitoring results are in the table below.
| Key Pollutants | Manganese |
|---|---|
| Sample Screening Level | 500 ng/m3 |
| 9/5/2010 | 6.91 |
| 9/11/2010 | 16.4 |
| 9/17/2010 | -- |
| 9/23/2010 | 22 |
| 9/29/2010 | 13.5 |
| 10/5/2010 | 87.1 |
| 10/11/2010 | 119 |
| 10/17/2010 | 91.3 |
| 10/23/2010 | 23.5 |
| 10/29/2010 | 21.5 |
| 11/4/2010 | 318 |
| 11/10/2010 | 23.8 |
| 11/16/2010 | 79.2 |
| 11/22/2010 | 5.04 |
| 11/28/2010 | 3.54 |
| 12/4/2010 | 93.5 |
| 12/10/2010 | 37.3 |
| 12/16/2010 | -- |
| 12/22/2010 | 51.2 |
| 12/28/2010 | 5.76 |
| 1/3/2011 | 5.78 |
| 1/9/2011 | 16.7 |
| 1/15/2011 | 16.3 |
| 1/21/2011 | 42.3 |
| 1/27/2011 | 4.67 |
| 2/2/2011 | 20.5 |
| 2/8/2011 | 22.5 |
| 2/14/2011 | 83.3 |
| 2/20/2011 | -- |
| 2/26/2011 | 13.3 |
| 3/4/2011 | 98.9 |
| 3/10/2011 | 47.6 |
| 3/16/2011 | 20.9 |
| 3/22/2011 | 19.9 |
| 3/28/2011 | 226 |
| 4/3/2011 | 52.8 |
| 4/9/2011 | 45.8 |
–– = Sample not taken or invalid
Other monitored toxic air pollutants for Gary-4th Ave/Railcats (PDF) (2pp, 59k)