The EPA began using a standard for concentrations of airborne particulate matter (PM) less than 10 micrometers in diameter (PM10) in 1987 (40 CFR 50.6). Particles of this size can be inhaled deep into the lungs and are considered to be responsible for most of the adverse health effects associated with airborne particulate pollution. The air quality standards for these particulates are an annual average of 50 µg/m3, with a maximum 24-hour concentration of 150 µg/m3.
The ESER Program operates three PM10 samplers, one
each at the Rexburg CMS and Blackfoot CMS, and one in Atomic City.
Sampling of PM10 is informational only as no chemical
analyses are conducted for contaminants. A twenty-four hour sampling
period is scheduled to run once every six days. Equipment and
measurement problems nullified a number of samples from each location
(four each from Atomic City and the Rexburg CMS, and one from the
Blackfoot CMS). The maximum 24-hour concentration was 46.76 µg/m3
on May 19, 2002, at Atomic City. The average, maximum, and minimum
results of the 24-hour samples are shown are shown in Table 1. Results
for all PM10 samples are listed in
Table C-5, Appendix C.
TABLE 1. Summary of 24-hour PM10 Values (µg/m3)
for each station.