An Optical PM monitor can be used to take a qualitative survey of the relative PM levels near a source of rock dust, potentially identifying areas of relatively high PM, known as a PM hotspot.
One place where such a survey could be conducted is in the the New Auburn, WI Wildlife Area, which surrounds three sides of the Great Northern Sand Mine in the town of Dovre.
My questions are:
- Is it worth surveying near this mine? is anyone interested?
- Can we access the land within the Wildlife Area to take measurements? While we can legally access the land as a park, its not clear that the area will be above water.
- Can we access the land in the spring?
New Auburn Wildlife Area Access
I knew of the mine through discussions with a Barron County resident, and found it on the Wisconsin DNR's map of sand facilities.
While the state's park map shows access and parking areas, it shows no formal paths:
Does anyone with local knowledge know what the area is like in spring? I expect significant seasonal variation.
On windhistory.com I was able to find a nearby wind plot in Rice Lake. It seems SE are prevail around the mine. The Wildlife Area is usually downwind of the mine:
Potential hotspot survey method
I'd like to try out the methodology detailed in the link above by Ott et al. in:
Passive sampling to capture spatial variability in PM10–2.5 Darrin K. Ott, Thomas M. Peters, and Naresh Kumar Atmospheric Environment 42 (2008) 746–756
Over four days, Ott et al. toured 60 sites in Iowa City with an optical PM monitor, taking 6 minutes of measurement at each site. The result was a hotspot map they used to deploy passive pm monitors for quantitative measurement.
While a qualitative survey with an optical PM monitor did not prove unsafe levels of PM, it did demonstrate a downwind hotspot.