By Jay T. Cullen

Previously unpublished data results from research expeditions in 2014 and 2015 are summarized here.  Overall the data indicate that:

1. Fukushima derived radiocesium was first detected 1500 km west of British Columbia Canada in June 2012
2. Contamination was detected on the continental shelf (near coastal waters) in June 2013
3. By February 2014 Fukushima radiocesium was present at levels similar to preexisting weapons testing derived ¹³⁷Cs
4. The timing of the arrival and levels of radiocesium in the contaminated plume are in reasonable agreement with existing ocean circulation model predictions
5. ¹³⁴Cs, a unique indicator of Fukushima impact given its ~ 2 year half life, increased in 2014 and 2015 relative to previous years indicating that peak concentrations are likely to arrive in 2016
6. Maximum combined radiocesium activities (¹³⁷Cs + ¹³⁴Cs) offshore as of summer 2015 are 11 Bq m^-3 of seawater are about 8-10 fold less than maximum activities measured in the 1960’s due to weapons testing fallout. Current levels do not represent a significant risk to ecosystem or public health

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