China stores least weapon-grade fissile material in nuclear club

2011-05-08 (China Military News cited from indiatimes.com)

China's stock of weapon-grade fissile material might be the lowest among the five-member nuclear club, with a new Harvard study estimating that the Asian giant has about 16 tonnes of enriched uranium and 1.8 tonnes of plutonium. The Belfer Center study makes a plus-minus margin of four tonnes for highly enriched uranium and .5 tonnes of plutonium. This is lower from most previous estimates that range from 17-26 tonnes of uranium and 2.1-6.6 tonnes of plutonium, says the study's author Hui Zhang. Zhang's article in the "Science and Global Security" says China stopped production of enriched uranium in 1987 and plutonium in 1990, diverting resources towards nuclear fuel used for civilian purposes. A careful satellite study of Chinese facilities and calculations of use of fissile material had led to these estimates. China's nuclear programme was aided by the erstwhile Soviet Union before Russia broke cooperation after Mao Zedong's assertive policies. The facilities were then located in south-west China — far from the coast and border with the Soviet Union — and became operational in the 1970s. The new plutonium estimate, says Zhang, is consistent with a US department of energy assessment from 1999 that China had a stockpile of 1.7–2.8 tonnes of plutonium for weapons. The stocks might be more modest than estimated, but this does not necessarily spell comfort for India as most of China's missiles are in the mid-range that covers the Indian landmass. Some Western reports put China's stockpile at 240 warheads, with 175 in active mode and 65 in reserve. But many missiles are not clearly distinguished as nuclear capable, fuelling confusion and panicky reactions. The study calculates that China's Lanzhou plant, operating continuously at full capacity up to 1980, would have facilitated about six tonnes of weapon-grade or 90% enriched uranium. The plant did not process weapon-grade uranium till 1987. The Heping facility located in Sichuan is believed to have begun operations around 1975 and stopped in 1987. Together, the Lanzhou and Heping gaseous diffusion plants would have produced roughly 3.8 million separative working units, enough to make about 20 tonnes of weapon-grade uranium. China produced plutonium for weapons at Jiuquan atomic energy complex in Gansu and the Guangyuan plutonium plant at Guangyuan in Sichuan. The Jiuquan reactor could have facilitated about 0.9 tonness of weapon-grade plutonium. China's existing smaller stockpile would be sufficient for current modernization, but if the US moves its missile defence and space weapons plans forward Beijing may have to produce more ballistic missiles, the study concludes.