Perhaps more troubling, TEPCO published data that the CS-134 and CS-137 radiation levels in seawater are 56 and 57 Bq/cm3 respectively.
While I-131 has a half life of 8 days, CS-134 has a half life of 2 years and CS-137 has a half life of 30 years. The CS-137 radiation will be affecting life in the ocean for at least 600 years.
I-131 radiation levels in the seawater near the Fukushima reactor peaked at 1,300 Bq/cm3 on April 8, 2011. That is 32,500 times the legal limit.
TEPCO announced that they are now planning to take steps to address this by dumping a mineral into the ocean that has the effect of absorbing radiation.