Fenceline PM4 crystalline silica concentrations near sand mining and processing facilities in Wisconsin
, 2015, Vol. 67, No. 10, pp. 53-59
Richards, J.; Brozell, T.
Communities near sand mines and processing facilities in Wisconsin have raised concerns regarding possible exposure to ambient respirable (PM4) crystalline silica. Fenceline PM4 (particulate matter captured with a 50-percent cut size of 4 micrometers aerodynamic diameter) crystalline silica concentration data were compiled at Fairmount Santrol Inc., Mathy Construction Inc. and U.S. Silica facilities. The long-term average PM4 crystalline silica concentrations ranged from 0.05 to 0.45 micrograms/m3 when sample values below the limit of quantification were treated as zeros. All of the long-term average concentrations were less than 20 percent of the Minnesota Department of Health’s and California Office of Environmental Health Hazard Assessment’s PM4 crystalline silica chronic reference exposure level of 3.0 micrograms/m3. The measured concentrations were consistently within the local background concentration range.