Ambient air monitoring was conducted on the grounds of a
secondary school, Wairarapa College in Masterton (Figure 1), at an
ambient air quality monitoring station operated by the Greater
Wellington Regional Council since October 2002. Co–located at the
site was a continuous PM10 (FH62; Thermo Scientific) analyzer. The
site was at least 150 m from the nearest road and approximately
1 km from the central business district. The land around the site is