Radon in Soils of Parts of Cameron, Hidalgo, and Willacy Counties, Texas

This study looks at part of the southern Rio Grande Valley where all of the
counties are ranked by USEPA as zone 3. The study area (see index map) includes
parts of Cameron, Hidalgo, and Willacy Counites all of which are shown as zone
3 in Figure 1. High-resolution airborne gamma-ray data from Duval (2005) as
well as regional data in Duval and Riggle (1999) indicate that specific
geologic units within the study area have uranium concentrations greater than 3
ppm eU. The geologic units in question are mapped by Page, VanSistine, and
Turner (2005) as Holocene floodplain deposits of the Rio Grande and as members
of the Beaumont Formation. This study examines whether the geologic units with
higher uranium concentrations have more potential for indoor radon than other
geologic units within the study area.

[Summary provided by the USGS.]