Mapping Radon Gas Levels in Pennsylvania Using GIS

Kristie Yesilonis, The Londonderry Science Consortium, Harrisburg, PA

     In this experiment, it was determined that by mapping Radon Gas levels by zipcode, Radon Gas Levels are higher in areas that have a lot of humanistic activity and development. The zipcode/radon results data layers were combined with data downloaded from the Pennsylvania Spatial Data Access, www.pasda.psu.edu, specifically the individual County urban areas maps. Additionally the State wide  "Naturalistic/Humanistic landscape matrix for Pennsylvania" data set (http://www.erri.psu.edu/web/projects/gappage.htm )  was layered with the Zipcode/radon data. The activity and development (ex. digging and dynamiting)  can sift and fracture the rock and allow radon to rise to the surface.  In Dauphin County there are higher radon levels in Lower Paxton Twp. where they are building several new malls, and townhomes. Susquehanna Twp. also has many new homes being built and carries high radon levels. Berks County has high radon levels around Reading, which is a fast developing area. Chester County’s high spots are located along Route 30  and in the suburbs of Philadelphia. Along Route 72  and Route 422 are the hot spots in Lebanon County. Adams County has high radon levels  around Gettysburg and along Route 16 S.  The radon test results data  were provided by Key Technology Inc., who listed all test results ,by zip code, who had their homes tested for Radon using their Key-Rad test kit.  Some variables involved with the Radon testing are the construction of the house, older homes are not built as tight as newer homes. Therefore there would not be as much radon in older homes because the air can circulate more than in newer homes. Another variable would be the homeowners method for taking the readings- sometimes people open all their windows to ventilate the house and try to get lower readings. Changes in the atmospheric pressure on the day of testing- the atmospheric pressure differs during the day, and also before a storm as well as the moisture of the soil under the house are all variable well.  If I could do this experiment over I would try to find out if radon travels through water. I think that my experiment could help residents trying to find out if they have radon in their home, or on an area they are building on.