RAPID: Time Series Sampling for Radionuclide and Biogeochemical Fluxes at F1 Time-series Station, Offshore Fukushima Dai-ichi Nuclear Power Facility

Woods Hole Oceanographic Institution, Woods Hole MA

Investigators

Abstract

The 2011 Tohoku earthquake off Japan resulted in a tsunami that severely damaged the Fukushima Dai-ichi nuclear power facility. Emergency cooling using seawater, in response to overheating of the facility?s reactor units 1, 2 and 3 and uncontained spent fuel pools, has led to run-off of contaminated waters to the adjacent Pacific Ocean that, cumulatively, measure > 10,000 higher than pre-tsunami levels and exceed the release of radionuclides to the marine environment from Chernobyl accident. With funding through this Grant for Rapid Response Research (RAPID), a research team at the Woods Hole Oceanographic Institution will participate in a JAMSTEC-led cruise in June-July 2011, and deploy a time-series sediment trap mooring at a station 80km off the coast of Japan. The specific goal will be to collect settling particulate radionuclide matter over the coming weeks and months through to an already-scheduled cruise to recover the moorings in May, 2012. By deploying traps at 500m and 1000m, the team will intercept particle-attached radionuclide settling out of the upper ocean and assess their fluxes into the deep ocean interior. They will collect fresh samples approximately every 2 weeks at each depth throughout the sampling period to complement ?snap-shot? sampling that will be conducted aboard the JAMSTEC cruise at the start and end of the deployment period. The team will also collaborate closely with Dr. Ken Buessler at WHOI (already funded separately, including a complementary NSF-RAPID project) who will be responsible for radionuclide analyses of particulate samples at no additional cost to this proposal. This project will handle preparation, deployment and recovery of the time-series sediment trap mooring as well as preliminary sample splitting, characterization of samples for biogeochemical properties and sample archiving. Radionuclides of primary interest at this time include 137Cs, 134Cs, 106Ru, 144Ce and 147Pm; other species (e.g. Pu isotopes) may also prove to be of interest within the lifetime of the deployment. Thus an important part of the project will also be to stand ready to provide further splits of these well characterized samples to US, Japanese and other interested international research groups in the future, as need arises. Broader Impacts: As learned in the aftermath of Chernobyl, establishing the distributions and activities of radionuclides present in the environment as soon as possible post-release is important to understanding the severity of the releases that have occurred, their implications for public health, and to establish "time zero" conditions against which the wider oceanographic community can subsequently track the fate of long-lived (conservative and biogeochemically-active) radionuclides. In addition to the strong international (WHOI-JAMSTEC) collaboration that has already been developed for this project, the team will share all data (banked with BCO-DMO at Woods Hole) and samples collected by this work with the wider national and international science community and public.