A popular topical quiz show on British television could put this question to its panel of ‘experts’: "What do rising beaches in the Far East, low-potassium glass vials in London, the troubled American nuclear power industry, and a Chinese headache have in common?" The answer is Taiwan, a sovereign island struggling to become less dependent on imported energy.
 
Nuclear energy represents the most cost effective way to obtain electricity, with potentially little environmental impact - except for the movement and storage of nuclear fuel and a the dreaded apocalyptic, ‘China Syndrome’ like power plant accidents. Human fallacy is the main cause of concern, when even trivial errors can have catastrophic effects, like the Chernobyl disaster a decade ago. But other major hazards come from extreme natural forces, such as earthquakes and tsunami (tidal waves).

Choosing a site where the station is to be built has to be carefully planned to avoid ground unsuitability. Unfortunately economic and political pressures can lead to the lowering of safety standards below that which is satisfactory.

                            A bit of geology
Figure b Three-dimensional schematic plate tectonic setting of Taiwan. (After Ho 1986).

The isle of Taiwan has a total area of nearly 36,000 sq. km, about the size of Switzerland; this largely mountainous patch of land marks the edge of the ‘Asiatic Continental Shelf’, a gently sloping, shallow-water platform east of the island. Taiwan has more than two hundred peaks with elevations of over 3000 meters. Indeed, steep mountain terrain above 1000 meters elevation constitutes about 32% of Taiwan’s land area.

Such dynamic landscape ultimately originates, like all other mountain chains, from the way that the Earth’s crust is broken up into a number of pieces, called plates. Because these plates rest on a mobile layer of the Earth, they tend to either collide or break up. Near Taiwan the Philippine Sea Plate, made of heavier oceanic rocks, is sinking beneath the Eurasian Plate at a rate of about 70 mm per year (see fig. a and b). This development, likened to a life of a child, was started with its conception 2-3 million years ago. As a result of this titanic push, what was once an ocean floor, then deeply overlaid  with the remains of micro-organism’s skeletons and sediments, started emerging, folding and fracturing in the process. Gestation lasted for a million years until eventually the compressed sedimentary rocks emerged as land and mountains. Mother nature had delivered. Taiwan was born.

But nature is very prolific. Plate collision movements have started again in the southernmost part of the island. The deep penetration of crustal rocks is not a smooth process. Friction between these sliding rock layers is only partially mitigated by the lubricating action of water which is mixed in with the rocks. Sudden jolts and thrusts are common at depth and are felt on the surface as tremors. It comes as no surprise that Taiwan has experienced many earthquakes throughout its history (see fig. c).
Seismic activity seems to be concentrated along linear ground fractures, called faults. More often than not, faults are hidden from sight and can only be detected by careful correlation of local seismic records. Sometimes, as  happened in 1951 in Hualien (see fig. d),  the fault slip behind the earthquake actually fractures the surface. In this instance the local fault (Milun) was displaced vertically by 1.2 metres and horizontally by 2 metres, a huge jump that caused massive and destructive tremors in the surrounding areas.

Apart from earthquakes, another clear sign of deep ground movements come from surface uplifts, such as risen beaches. British and Chinese researchers now have evidence that parts of the eastern coast have undergone constant uplift. "What we have found is that the whole region, albeit seismically quiet at present, in the past was subjected to strong earthquakes; we fear that a new seismically active phase could return at any time," Prof. Claudio Vita-Finzi, from Department of Geological Sciences at University College London said.

Evidence of coastal rise comes from dating reefs and marine terraces going back 10,000 years.
Detailed study of three sections along the Coastal Range mountains (fig. b) of east Taiwan indicate that there has been different rates of uplift. The minimum uplift rate of the recent coastal terraces (less than 9000 years old) around the island ranges from 2 mm/year to 6.4 mm/year, averaging about 4 mm/year.
In 1971, a survey showed that an area of 180 km2 south-west of Hualien had moved more than 3 metres north.

These different rates of ground movement confirm the suspicions that there are many active faults at work, all capable of generating destructive earthquakes.

This detailed study of coastal movements was made possible by the development of a cheaper and faster way of dating fossil shorelines by Prof. Vita-Finzi. This new method is called ‘First-order 14C dating’:
 

Carbon is everywhere in the plants and animals that populate the Earth: its unique ability to link up with  other atoms and, more importantly itself enables carbon to form complex chains and loops which provide the chemical backbone of life.A ‘standard’ carbon nucleus is made up of six positively charged particles called protons and six other particles called neutrons, which have no electrical charge. This gives carbon an atomic mass of 12. Protons are responsible for the electrical and chemical properties of an element. Adding one extra proton in the carbon nucleus would turn it into nitrogen. But the number of neutrons can vary. Indeed carbon comes in six different ‘flavours’, called isotopes, which differ only in having a different number of neutrons.  There are two stable isotopes of carbon (atomic mass 12 and 15) and four radioactive ones (10, 11, 14, 15); within a certain characteristic average period, called ‘half-life’, half of all the radioactive isotopes eventually decays into stable carbon varieties.Carbon-14 is used in ‘carbon dating’, the most widely used method for determining the age of organic material. It has a mass number of 14 and a half-life of around 5730 years.As a result of cosmic radiation, a small number of atmospheric nitrogen nuclei are continuously being transformed by neutron bombardment into radioactive nuclei of carbon-14: a neutron knocks a proton out of nitrogen and takes its place.   Some of these radiocarbon atoms find their way into living trees and other plants in the form of carbon dioxide, as a result of photosynthesis. When the plant or plankton is eaten, photosynthesis stops and the ratio of radiocarbon atoms to stable carbon atoms begins to fall as the radiocarbon decays. Based on the assumption that the isotope ratio of carbon in cells of living things is identical with that in air, Willard F. Libby (1908-80) and his co-workers in 1946-47 developed a technique designed to measure the ratio 14C/12C in the specimen. This method made it possible to estimate the time that has elapsed since, for instance, a tree was cut down.   Radio Carbon dating has been shown to give consistent results for specimens up to some 40 000 years old, though its accuracy depends upon assumptions concerning past intensity of  cosmic radiation.  Unfortunately carbon dating is expensive and often subject to serious delays. As a consequence this method tends to be used more sparingly and less effectively than it might be. Furthermore sample preparation requires considerable technical skill and complex equipment, and prolonged counting may be required to obtain acceptable error values. Yet there are many problems in geology and archaeology whose investigation requires ages which need not be very precise provided they are reliable.  Prof. Claudio Vita-Finzi of University College London disclosed in 1983 a new method which can estimate ages for samples dating back up to 8000 years, with an uncertainty  of 1500 years or less. This is achieved by using standard laboratory equipment; the results are significant savings both in time and analysis costs. Approximate ages can thus be obtained promptly and results made available to the collector while still in the field.Shells, or other carbonate rich material are continuously stirred through a water-cooled mixture.  Carbon dioxide is produced by treatment with hydrochloric acid ( HCl). CO2 is then gathered with absorption liquid made of an equal mixture of Permafluor V and Carbosorb.At this point 14C counting can be carried out on standard lab equipment, such as a Packard Tri-Carb 2260XL machine which is widely used in many chemistry and bio-chemistry laboratories.

 

Energy Sources

Taiwan’s seemingly endless economic growth is hampered by the island’s shortage of indigenous energy resources. Its coal reserves amount to only 100 million tons, oil and natural gas 560 million litres and 753,000 million cubic meters respectively. Total hydropower potential has been estimated at 5,047 megawatts, of which 1,912 megawatts has been developed, primarily along several major rivers.
This is not a lot. Given that the total energy demand in Taiwan increased from the equivalent of 17,000 million litres of oil in 1974 to 83,000 million litres in 1996, an average annual growth of 7.1 percent, it is clear that the island’s natural reserves are vastly inadequate. Indeed over the past two decades, indigenous energy supplies have accounted for a progressively smaller proportion of annual usage, dropping from 30 percent in 1974 to 4 percent in 1996; as such, the imported energy share had to rise correspondingly. And it has: expenditures for imported energy totalled US$7.8 billion in 1996, of which imported oil accounted for 73 percent or US$5.7 billion.
Energy saving schemes and renewable energy sources cannot meet the continuously increasing thirst for energy. Building more nuclear power stations seems to be the only serious option. But is it a sensible one?
 

Nuclear power

Politicians think so. At present Taiwan has six nuclear units operating. They are housed in three nuclear power stations, all of which are owned and operated by the state owned Taipower. In 1996 these six nuclear units produced 30 percent of Taiwan's total electrical output. In 1980 the government had already began planning the construction of a fourth nuclear power plant. Support for the project has been slowly undermined, however, by a growing awareness amongst the general public about environmental issues.
Increasingly vehement protests against nuclear power in general have also emerged. These protests have pressured many legislators into voting against the budget for the power plant, and in particular, legislators representing constituencies where the plant is planned to be built.
Finally, after years of political and industrial lobbing by both pro and opposing parties, in November 1997 the Taiwan Congress cut all of the financing and shut down the project.
Kao Chen-Yuan, convenor of Taiwan’s Green Party, boasted "This is not only a success for the ten-year anti-nuclear struggle but also a blow to the Clinton-Jiang meeting, in which the USA agreed a 40 billion deal of nuclear facilities export to Taiwan". Indeed, part of bilateral economic agreements between the two countries’ leaders includes the undertaking to supply American reactors to Taiwan.

Taiwan is in a very critical and strategic position in the Asian and world-wide anti-nuclear movement. "the reactors of the fourth nuclear power plant in Taiwan are the first deal for the United States to sell its nuclear reactors to Asia in the recent ten years. It is a critical contract designed to help saving the obsolete American nuclear industry." Kao explained (for a full account of this political journey  please see insert).
 

However, the success for the anti-nuclear lobby proved to only be momentary. It was finally vetoed by the Taiwan Congress. Now the opposition needs a hefty 2/3 majority to overrule this veto.

After all the parliamentary activity and Green Party commitment, it looks likely that the fourth power station will eventually be built. Unless…, new evidence coming from a kitchenette on the fourth floor of  University College London, is taken seriously.
 

Within highly seismic regions such as those near the San Andreas fault in California, the Alpine Fault in New Zealand, and the Atacama Fault in Chile new building projects have to follow stringent safety construction regulations.

Building nuclear power stations on potentially seismic areas is a recipe for disaster: "we could be witnessing an extraordinary gamble with the fundamental forces of nature. When this seismic hiatus is over, even minor tremors could damage the nuclear plants’ cooling systems with the kind of consequences that we sadly witnessed at Chernobyl" Vita-Finzi said.

Unfortunately warnings of environmental hazards are usually ignored or given little consideration by energy starved countries when faced with a choice between progress and stagnation. In the case of Taiwan, this vibrant, but very young democracy, might be meeting its first real chance of translating real concern into constructive dialogue between opposite views.