INTRODUCTION
The more than 180 atmospheric and underwater tests at Moruroa and
Fangataufa atolls have dispersed in the environment or created
crude nuclear waste dumps underground of hundreds of kilograms
of plutonium and other highly radioactive fission products. To
say that French nuclear tests pose no problem for the environment
is to argue that:
These two claims are obviously false:
* Moreover, French tests, whether in the atmosphere or underwater, have left enormous quantities of wastes at the test site:
- contaminated earth, waste from decontamination of equipment, contaminated clothes etc. There is no official acknowledgement of the storage, transfer or eventual clean-up of these thousands of tonnes of waste.
- The interior of the atoll is effectively a vast, unregulated high-level radioactive waste dump.
CLAIMS THAT RADIOACTIVITY FROM UNDERGROUND TESTS ARE PERMANENTLY CONFINED WITHIN THE ATOLLS IN THE LONG TERM ARE SIMPLY NOT CREDIBLE.
The Commisariat a l'Energie Atomique claims that through a process of vitrification resulting from the heat of the test explosion, radioactive material from the tests is completely confined in the atoll's basalt structure. However, vitrification is difficult to master even in an industrial environment, and completely unpredictable under testing conditions. Chimneys and fractures allowing water to permeate into the atoll have been created. The evidence suggests that shocks caused by successive explosions have created an additional problem in confining the radioactive materials.
A simple comparison with the research required for the storage of high level radioactive waste in France illustrates the discrepancy in approach to safety between the two. What would be the reaction if nuclear waste was stored under the sea in a region regularly impacted by very large explosions?
In terms of Moruroa's suitability as a long-term radioactive storage site, the scientific missions that have been allowed very limited access to Moruroa for exploratory investigations have been united in their criticism, saying water-permeable coral atolls are unsuitable sites for nuclear testing.
* Commander Jacques-Yves Cousteau's 1987 mission noted: "Some researchers believe that it is natural barriers that play the most important role in the storage of nuclear waste. Consequently the storage site must meet very strict criteria. One of the most important of these is the absence of water, and especially of circulating water. Whatever the circumstance, the volanic stratum of an atoll, totally saturated with water, is the worst choice! Another important criterion is the absence of factures. But, in addition to the natural fractures affecting the volcanic layer [at Moruroa], the explosions cause the formation of a veritable network of fissures around the storate site (the test chamber). Their adsorption coeffiecient is much less than that of vermiculites (micas) or of illites (clay). Moruroa is consequently a very poor site for storing nuclear waste." (p.32, Cousteau Report)
* Cousteau concluded nuclear testing had caused accelerated and premature aging of the atoll. "The tests conducted under the lagoon still produce fissures and subsidences that affect the external slope of the atoll. The risk of collapse in the southern zone is not excluded: in faact, very wide (one to two metres) longitudinal faults penetrate the upper part of the outer flank over some tens of metres...
It is clear that the permeability of the volcanic layer is locally increased by fractures caused by underground tests...The premature and accelerated aging of the atoll certainly explains, in large part, the imminent transfer of the large yield nuclear tests to the atoll of Fangataufa..". (p. 36, Cousteau Report)
* The Atkinson report noted: "Underground testing may be acting to alter the ambient conditions, particularly along the north east and south west margins, both areas of particularly severe testing as indicated by fissuring, subsidence and submarine sliding of the limestones. Hydrological consequences of these effects are increases in the vertical transfer rate of water and the direct lateral exchange rate between ocean and atoll interior...The French claim that any leakage from the volanics into the limestone will be stopped by the impermeable transition zone is not borne out by the data inspected... the claim that the transition zone acts as a barrier to long-term leakage can, on the basis of geologic evidence, be discounted. The volcanics in their virgin state offer a poort to moderate geo-chemical barrier and a moderate to good hydrological barrier. The testing programme is reducing the effectiveness of both." (p.9, Atkinson Report)
* The Atkinson report concluded that the structural integrity of Moruroa had been impaired by fissuring, subsidence and submarine slides; that there was doubt about the ability of the transition zone around each test blast to act as a barrier to radioactivity migrating out of the atoll; and that the volcanic core in which tests take place had been severely altered by the tests. "At the underground test sites, water is avilable for leaching the radioactive material (which can be equated to high-level waste). Mechanisms exist for the transport of this contaminated water to the biosphere at least in the long term." (p. 11, Atkinson Report). The report defined the long term as greater than 500 years; the half-life of plutonium is 24,000 years.
THE FRENCH AUTHORITIES CLAIM THAT NO LEAKAGE FROM UNDERGROUND TESTS HAS OCCURRED.
In fact, the scientific missions which have been permitted access to Moruroa, although only allowed to take a handful of sample, have all detected the presence of artificial radioactivity either in or around the test site. This include radioactive iodine, cesium 134, and plutonium in the lagoon and outside the 12 mile exclusion zone.
The Atkinson mission in 1984 noted: "About 20 Gbq (Gigabequerels) of plutonium is transported annually to ocean waters from the lagoon at Moruroa. It was not possible to determine the original source of sources of this plutonium.... the one positive result is consistent with there being a local source of particulate plutonium before the storms of 1981. The lagoon is a possible source." (p. 143, Atkinson Report)
* The French authorities themselves told the Atkinson team that the sediments of the lagoon contained 10-20 kg of plutonium (ingestion of one microgram can cause fatal cancer; 20 kilograms of plutonium is sufficient to manufacture several nuclear bombs).
* The Cousteau mission found iodine 131 in 1987, which has a half life of only eight days, and so must have resulted from a recent test. The report noted: "After having mentioned the possibilities of a leak by a fissure which had propagated from the cavity right to the surface, traversing the basalt then the coral, of by the emplacement well which was more or less impervious, authorities of the CEA provided us with an explanation for the presence of this iodine. On 20 May, 1987, during post-test monitoring drilling, caried out after a test, an accidental leak occurred... we were assured of the quite exceptional character of this type of accident. Despite the plausible nature of the explanation... we have not been able to verify its veracity directly." (p. 21-22, Cousteau Report)
* The Cousteau mission also found Cesium-134 -- an artificial radionuclde not present in atmospheric fallout -- and suggested it might "be necessary to attribute the origin of the Cs-134 to the underground tests". The French authorities provided no explanation of the presence of Cs-134 in the Cousteau samples, but three years later suggested is was a typographical error in the Cousteau report. (p. 23, Cousteau Report)
* US scientist Norm Buske detected cesium 134 in plankton samples taken outside the 12 mile zone during a Greenpeace mission in 1990.
* In 1992, the French Government, wanting to contradict Buske's finding, requested the International Atomic Energy Agency undertake a study of plankton sampled 12 miles from Moruroa atoll. The study revealed contamination by plutonium which could only have come from leakage due to fissuring of the atoll or dumping of radioactive waste in the zone. No official explanation was for the presence of plutonium at this sampling station.
Other examples of environmental consequences of the testing programme include:
* On July 25 1979, an explosion created serious fractures in the side of the atoll (which were partially filmed by the Cousteau Mission) and a subsequent tidal wave engulfed installations.
* In spring 1981, cyclones removed radioactive waste covering a zone of 30,000 square metres in the northern part of Moruroa atoll.
* Restrictions prevent long stays on Fangataufa atoll where larger tests have been conducted since 1988 because of earlier contamination from atmospheric tests.
The French authorities have frequently pointed out the low population density around the atolls of Moruroa and Fangataufa. It must be remembered that several European countries, situated two or three hundred miles from Chernobyl were seriously affected by that disaster, and radionuclides from the accident were transported atmospherically around the globe. Ocean current are extremely effecient carriers of radioactive contamination, and the accumulation of radiation in the food chain would do irreparable damage to the maritime resources of the coastal states of the Pacific.
With this evidence, the French Minister for the Environment, Corinne Lepage and President Chirac cannot deny the effects of nuclear tests on the environment of French Polynesia and international waters. Neither can the claims that tests are safe coming from the military and nuclear industry be credible, given the vested interests of these experts. Only a fully independent and comprehensive study over several years which has full access to all data currently "military secret", and which has unrestricted opportunities to sample and monitor the atmospheric, oceanic and terrestrial environments of Moruroa and Fangataufa can hope to establish the real environmental consequences of nuclear testing at the atolls.
--24 July 1995