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Only the human-made radioactivity is
dangerous.
Jerry
----- Original Message -----
From: Prof.Dr.Klaus.Becker
Sent: Monday, May 19, 2003 2:46 PM
Subject: Fwd: " OIL, GAS EMIT MORE RADIOACTIVITY THAN NUCLEAR " [FW]
(fwd) > >............... > > > >NUCLEONICS WEEK -May 15, 2003 > >NORTH SEA STUDY: OIL, GAS EMIT > >MORE RADIOACTIVITY THAN NUCLEAR > > > >North Sea oil and gas operations now contribute more > >man-made radioactivity to North European marine waters > >than the nuclear industry, according to the Marina II study, a > >European Commission (EC)-funded project undertaken by > >international experts to update data on the impact of radioac- > >tivity in the region's seas. > >The study found that nuclear industry discharges to sea > >are back at the same level as the early 1950s, and that natural- > >ly occurring radioactive materials (NORM) now dominate > >doses to the European Union (EU) population from industrial > >discharges, both in terms of alpha activity and overall impact > >(collective dose). > >Norway is the largest oil producer in the North Sea and is > >estimated to provide the greatest impact from current dis- > >charges. Norway is closely followed by the U.K., with Den- > >mark and the Netherlands contributing relatively little. > >In 2000, according to the study, radioactive discharges > >from the non-nuclear industries were estimated to contribute > >more than 90%of the European population's total exposure > >from discharges into the marine region covered by the Ospar > >(Oslo &Paris) Convention. Oil and gas operations contribut- > >ed 35.3% and phosphates, 55.4%. > >This compared with the contribution to the collective > >dose rate from discharges of 3.8% from British Nuclear Fuels > >plc's (BNFL) Sellafield reprocessing complex, 1.7% from > >Cogema's La Hague facilities, 3.3% from weapons fallout, > >0.2% from Chernobyl fallout, and 0.1% from nuclear power stations. > >However, the overall impact of the discharges to the EU > >population can be gauged from the fact that, even at the dis- > >charges' peak, the collective dose rate was around a factor of > >20 less than the annual collective dose from natural radioac- > >tivity in the marine environment. > >The Marina II results have been circulating within the > >expert community for some time and have been placed on the > >Internet and issued as a "Radiation Protection 132 Pre-Publi- > >cation Copy," but the official report is not expected to be > >published for another month or so. > >NORM is discharged as a result of phosphate fertilizer > >production, although such discharges have been reduced > >since the 1990s, and from the extraction of oil and gas from > >the continental shelf in the North Sea, mainly in the Norwe- > >gian and U.K.sectors. > >NORM accumulates as scale inside pipework and valves > >at offshore oil and gas production platforms. It also gathers as > >sludge in separator tanks and other vessels. It is discharged in > >"produced water " and its radionuclides of radium--226 and > >Ra-228 and Pb-210 (lead) become available in concentrated > >form for consumption by marine biota. > >The study was managed by U.K.-based NNC Ltd.under a > >contract with the EC's Directorate General for Environment > >(NW, 22 March '01,11). NNC worked with experts belonging > >to scientific institutions such as the U.K.'s National Radio- > >logical Protection Board,the Netherlands' Institute for Fishery > >Investigation and NRG nuclear consultancy, Denmark 's > >Riso National Laboratory, France's CEPN, Russia's SPA > >Typhoon, and Ireland's University College in Dublin. The > >team collaborated with Greenpeace, IAEA, the International > >Union of Radioecologists, Friends of the Earth, and the World > >Nuclear Association. > >The study's results have been considered by the Ospar > >parties and resulted in a decision to recommend the reporting > >of discharges from the non-nuclear industries. > >The Ospar Convention for the Protection of the Marine > >Environment of the North East Atlantic was established in > >1992. Its target is to ensure that radioactive discharges to the > >marine environment in the region are reduced to levels "close > >to zero" by 2020.. The Marina II data is expected to help > >establish a baseline against which progress in implementing > >the strategy can be evaluated. > >Marina II concluded that the overall civilian nuclear and > >other anthropogenic inputs of radioactivity into the North > >East Atlantic decreased by several orders of magnitude for > >alpha-and beta-emitters and for tritium since the maximum > >levels were reached in the 1960s and early 1970s. Over the > >same period, this resulted in reductions in radionuclide con- > >centrations in the marine environment and in the individual > >doses to members of critical groups and in collective doses to > >the public. > >Since the mid-1980s, the main contribution to discharges > >of beta activity into the Ospar region is from nuclear repro- > >cessing while the discharges of alpha-activity have been > >dominated by the phosphate industry and, later, by oil pro- > >duction in the North Sea. > >Remobilization of radionuclides from the marine sedi- > >ments is the other major factor in radioactive exposure. "The > >importance of this phenomenon in the Irish Sea results from > >the fact that the discharges from Sellafield have been reduced > >around 100-fold since the 1970s," said one of the study's > >authors, NNC 's Mark Gerchikov. > >"Now these remobilized radionuclides are more important > >than those resulting from any new discharges. In practice, this > >means that reducing current discharges to zero -Ospar poli- > >cy -will not affect concentrations of some important radionu- > >clides such as the plutonium isotopes." > >Nuclear industry discharges are still dominated by repro- > >cessing activity. Excluding the Chernobyl fallout in 1986, > >the input of beta activity (excluding tritium,which has a very > >low radiotoxicity) into the Ospar region decreased by more > >than a factor of four from 1986 to 1991. By this date, the > >annual discharge had reached the same level as in the early > >1950s. The reason was the major reductions in discharges by > >reprocessors BNFL and Cogema. > >Over the same period, the discharges of alpha activity into > >the Ospar region from Sellafield and La Hague decreased by a > >factor of three. Inputs of tritium, which decreased after the > >mid-1960s, have increased since the mid-1980s due to the > >increase in reprocessing at La Hague. > >The Marina II study can be accessed at: > >( http://www.europa.eu.int/comm/environment/radprot/execsummary.pdf ). > >-Pearl Marshall, London > > ============================ Klaus Becker, Boothstr. 27, D-12207 Berlin Phone/Fax: 0049-30-772-1284 |