The Occurrence of Radon on the Tobique First Nation Reserve and Its Implication for Radon Occurrence along the Saint John River Valley

A survey of 6 large public buildings on Tobique First Nation land in northern New Brunswick, showed five of them to be above the acceptable limit of 200 Bq/m. As most of the 350 homes on the Reserve are located close to any one of these buildings, the concerns generated by the test results, and resulting anxiety for radon in their own homes by residents, was high. This was fueled by the historic high incidence of cancer on the Reserve. While Health Canada recommends a 90 day test, this wait was unacceptable to the Chief and Council. Consequently, a two day residential radon test was conducted for each of the 350 homes on the Reserve, as this was a relatively fast way to screen homes into three categories. Over a period of three weeks, two E-Perms were installed in each of the 350 homes. In addition, several soil vapour monitor wells were constructed to assess the levels of radon in the soils near some of these homes. An analysis of Uranium content in soils was also undertaken. The results indicate that greater than 50 % of the homes have radon levels greater than 200 Bq/m, with 11.7% of these showing levels greater than 600 Bq/m. The paper will discuss the implications of the 2 day high density radon survey; its relationship to the 90 day test; the relationship of radon levels in homes to background levels in soil; and the implications for numerous other communities along the Saint John River Valley that potentially lie on the same sand and gravel deposits that lie beneath the reserve.