PurpleAir: Initial Data Analysis and Plant Visit

Hello again from Indiana, PA! We had a great week where we ran more calibrations, had our second field day (with sunny, ozone-producing weather!), and went on a beautiful hike with folks from IUP and Penn State to investigate potential methane outgassing along a trail. The topic I want to focus on for this blog post was the work we did on the PurpleAir project.

I started analyzing the data from the two sensors we left in Wisconsin, and it was really exciting to see how the data was matching up well. One of the sensors is at a farm next to an active frac sand mine. The other sensor is at a nearby property acting as a background site—that is, a site that has similar air quality to the farm but that lacks proximity to the mine. I had to mess around with the data for a bit to work out some sticky parts that were keeping me from working easily with it. For example, the date/times measurements were collected at were listed as values instead of date/times in Excel, which meant that for a while I was unable to graph PM levels by date/time.

I was really excited about this data because it is matching up incredibly well in many ways! The fact that the data matched up so well between the two sites was really encouraging because it makes it easier to identify events when they happen. In other words, because the data matched up so well, if there are any differences in the data for the two sites, we may be able to identify the increased values of PM as events which introduced greater particulate pollution into the air at that site. Even though we are monitoring the mine to see if it introduces any particulate pollution, we actually only saw greater levels of particulate matter at the background site. I emailed the PurpleAir hosts—it will be interesting to see if these events are from something like them grilling in their backyard, using a saw, or something else entirely!

The other aspect of PurpleAir which we worked on this week was visiting Monessen to see the coke plant causing particulate pollution. This plant has already agreed to a $1.5 million settlement for Clean Air Act violations. However, some people are still concerned about the particulate pollution from this plant. When we approached the plant, I was struck by the fact that it was right next to the local grocery store (see the photo to the left). I think the fact that this plant was right in the middle of town and was so close to people’s daily activities reminded me of the impact a plant like this can have. Whatever negative health impacts this plant may be posing, the people living in this community likely did not chose to take on this burden of pollution, and some people for a variety of reasons are unable to remove themselves from any hazards that may be posed by this plant. Seeing the actual plant has motivated me even more to monitor the particulate pollution in Monessen and to do my best to collect some data which will help us understand the particulate pollution this plant may be causing.

Overall, the PurpleAir project has so far been a really cool way to learn more about how data can reveal patterns and events! It will also be great practice in reaching out to community members and organizations as I continue trying to find people to host PurpleAirs on their homes in Monessen. Thanks for reading!