The Pacific Sandpiper, a specially built cargo ship with safety features far in excess of those found on conventional vessels, left Britain's Barrow port bound for Japan the other day. The security surrounding its departure on Jan. 21 indicates that something out of the ordinary is aboard. The Pacific Sandpiper and several sister ships make no port calls on their voyages between Europe and Japan because they carry potentially lethal nuclear material. But the elaborate and costly arrangement casts light on two of the most problematic and controversial aspects of civilian nuclear power - how to prevent the spread of nuclear weapons material and knowhow to terrorists and rogue states, and how to store nuclear waste safely for the long-term when it can remain radioactive for hundreds of years. With the number of power reactors expected to rise from 435 in 31 countries to nearly 570 in 42 countries by 2020, and with much of this expansion expected to take place in Asia and the Middle East, the need for safeguards on uranium or plutonium processing that could be used to make nuclear weapons is obvious. High-level radioactive waste is accumulating at a rate of about 12,000 tons per year worldwide. Without a long-term solution, the pile of radioactive "rubbish" will become so big and so widely dispersed that it may be impossible to manage safely.