Canadian scientists detect “significant” concentrations of radioactive material off West Coast, levels double in months since last test

Researchers say more work is needed to track movement of radioactivity across Pacific

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Department of Fisheries and Oceans Canada (pdf), Oct. 22, 2014 (emphasis added): Arrival of Fukushima radioactivity in North American continental waters… The radioactivity plume was transported northeastward towards North America by the Kuroshio Current… Water samples were collected… in June of 2011, 2012 and 2013 and February, 2014 on a line (Line P) extending to a location (Sta. P26), approximately 1500 km west of Victoria, BC… [W]ater samples collected in June, 2012 at Sta. P26 detected 134Cs at levels indicating the presence of contamination from the Fukushima nuclear reactor accident. The 2013 results revealed the presence of 134Cs in the upper 100 m along the entire length of Line P indicating that the Fukushima signal had fully arrived in Canadian territorial waters. Levels of Fukushima 137Cs were about 1 Bq/m3 in June, 2013 which is equivalent to previous background levels of 137Cs from atmospheric fallout. These levels had increased to values of about 2 Bq/m3 by February, 2014. These 137Cs concentrations are significant, but are several orders of magnitude below those that would be considered a threat to the environment or human health.

Call with Woods Hole Oceanographic Institution marine chemist Ken Buesseler, June 2014:

  • At 25:45 in – Buesseler: The question is, ‘How much higher will [the concentration of radionuclides] get with the arrival of 134Cs and the other isotopes?’
  • At 2:745 in – Buesseler: A paper that came out last year [shows] in a couple of years it’s actually going to be higher than its going to be on the front edge, kind of makes sense. But what’s really disturbing, and what concerns me, is when I saw this paper was there wereno data to test this.
  • At 44:45 in — Question: I’m wondering if there are other radionuclides that might not travel with the cesium. Maybe they’re just not as significant or not as many — but couldn’t there be other radionuclides, even if the cesium didn’t show up?… Buesseler: There are other isotopes that were released… What’s happening today off Japan… offshore, maybe 100 Bq/m3 of cesium, but the level of strontium-90 is almost the same… The ground waters that are a continued source tend to be enriched in strontium-90 [and] any number of isotopes including strontium-90… I would say the concern needs to move more towards strontium-90 and it is there at almost equal concentrations, it’s a bone-seeking isotope and therefore it stays in the fish for hundreds of days, not a couple of months, and in our systems as well… That is by far, to my mind, a much greater concern for new releases that will show up on our shores 3 years from now.
  • At 54:00 in — Buesseler: Those ocean currents would carry any isotope with them… 134Cs, it’s kind of like the canary in the coal mine [for] other isotopes… I share you’re concern about some of these fish, mammals… We need monitoring, we need measurements, and so far it’s taken the public to really make that happen in the ocean and the water, and I hope that it continues for other isotopes

Full teleconference here

Top Headline: ‘Fukushima radiation identified off northern California’ — 50% of samples around West Coast test positive — 7.7 Bq/m3 of cesium near California shore, expected to keep rising for years to come (MAP)

Statesman Journal, Nov. 10, 2014 at 8:22a ET: Fukushima radiation identified off northern California — Low-level radiation from Japan’s Fukushima nuclear accident has been detected in multiple samples of ocean water off the Pacific Coast of the U.S. and Canada, the Woods Hole Oceanographic Institution is reporting. The sample nearest to shore was taken about 100 miles off the coast of Eureka, in Northern California… Massive amounts of contaminated water were released from the Fukushima Dai-ichi nuclear power plant… Radioactive water has continued to leak and be released from the complex… No state or federal agency is testing Pacific waters for radiation… [Ken Buesseler, a WHOI marine chemist] is looking for cesium-134, the so-called “fingerprint” of Fukushima…  He’s also looking for higher-than-background levels of cesium-137, another Fukushima isotope that already is present in the world’s oceans… Buesseler partnered with a group of volunteers on the research vessel ‘Point Sur’ to take a series of about 50 samples offshore, from Dutch Harbor, Alaska to Eureka. So far, about 20 of those samples have been analyzed, and 10 have been positive for cesium-134…

Ken Buesseler, WHOI: “The models predict cesium levels to increase over the next two to three years, but do a poor job describing how much more dilution will take place and where those waters will reach the shoreline first.”

Ken Buesseler, Reddit’s ‘Ask Me Anything, Nov. 10, 2014 at 8:30a ET: I’m Ken Buesseler, an oceanographer who studies marine radioactivity. I’ve been doing this since I was a graduate student, looking at plutonium in the Atlantic deposited from the atmospheric nuclear weapons testing that peaked in the early 1960’s. Then came Chernobyl in 1986, the year of my PhD… The triple disaster of the 2011 “Tohoku” earthquake, tsunami, and subsequent radiation releases at Fukushima Dai-ichi were unprecedented events for the ocean and society…  the cooling waters and contaminated groundwater enter the ocean directly, and still can be measured to this day. Across the Pacific, ocean currents carrying Fukushima cesium are predicted to be detectable along the west coast of North America by 2014 or 2015, and though models suggest at levels below those considered of human health concern, measurements are needed. That being said, in the US, no federal agency has taken on this task… new sampling efforts further offshore have confirmed the presence of small amounts of radioactivity from the 2011 Fukushima Dai-ichi Nuclear Power Plant 100 miles (150 km) due west of Eureka. What does that mean for our oceans?

Also from today: Canadian scientists detect “significant” concentrations of radioactive material off West Coast, levels double in months – Marine Chemist: “Much greater concern” over Fukushima releases that will be hitting shores of US & Canada; Lack of data “really disturbing” (AUDIO

 

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