Sheranchuk's little flat was three kilometers from the plant, but this night luck was with him. An ambulance moved slowly past, and at his hail it stopped and gave him a lift. Sheranchuk half-recognized the doctor as a colleague of Tamara's, and the man knew who Sheranchuk was as soon as he gave his name. He had just had a call to attend a little girl who had swallowed something she shouldn't have, he explained — yes, yes, the child was quite all right, only a little sick from having her stomach pumped out — and he was now on his way back to the clinic. But there was no real hurry, and he was glad to go a couple of minutes out of his way for Tamara Sheranchuk's husband.
The ambulance circled around a man on a bicycle to take the engineer to the plant fence. He thanked the doctor and got out, fumbling for his papers as he watched the ambulance slowly start away. Although on the other side of the fence the Chernobyl Nuclear Power Station was almost as brightly lighted as in daytime, on this side it was a peaceful middle-of-the-night scene. The only things moving were the ambulance, the bicyclist, and some early-rising health faddist, it seemed, walking with great arm-swinging strides along the road and not even glancing at Sheranchuk or the gate guard.
The funny thing was, Sheranchuk discovered, that now that he was actually at the plant, he was beginning to feel quite drowsy at last. He could turn around and go back to bed easily enough.
He smiled to himself, his mind made up; no, he was this far, he would go in and see for himself just what they were doing with Reactor No. 4.. .
He was actually displaying his paprusbka to the gate guard when the world changed around him.
There was a sudden orange-white flare of light, a flower of flame overhead, the shattering, hurtful sound of a vast explosion. "In God's name!" Sheranchuk cried, clutching at the guard's arm as the two of them stared up in horror.
The noise did not stop. A siren screamed inside one of the buildings. There was a distant sound of men shouting. "But this is quite impossible," the guard bawled accusingly in Sheranchuk's ear.
Sheranchuk's mouth was open as he stared up. The great ball of bright flame was floating away and diminishing, but behind it was a sullen, growing red glow. To the other noises was added the patter of a shower — no, a downpour! — but it was not rain that was falling. It was bits of stone and brick and metal, pelting down all around them. "Yes," Sheranchuk said dazedly, "it is quite impossible."
But it had happened.
Chapter 5
The Chernobyl Power Station contains four units, each of them an RBMK-1000 "pressure-tube" reactor. The RBMK is not the Soviet Union's only nuclear power generator, but it is the favorite. Across the USSR nearly two dozen such units are installed and operational, and the 1000-series models, each of them rated at 1000 megawatts of electricity, are the largest and newest in operation, though even larger ones are beginning to appear.
The fuel is uranium dioxide, which is encased in steel and zirconium tubes and inserted into a huge mass of graphite blocks. (The purpose of the graphite is to be a "moderator." Nothing is needed to make uranium atoms fission — that is to say, break apart — and when they do that they produce atomic energy in the form of heat. They do it naturally all the time; that is why uranium is called "radioactive." As each atom fissions, it releases neutrons which strike the cores of other atoms and cause them to fission too. However, the naturally released neutrons whisk through so fast that they only rarely cause fission in another atom; they need to be slowed down to make a reaction go at the right speed to be of use to human beings. Graphite, along with a few other materials, has the capacity to "moderate" or slow down these escaping neutrons, and so in a reactor the speed of the reaction can be controlled.)
Along with the fuel tubes, the slab of graphite is pierced by nearly seventeen hundred pipes containing water. As the uranium fissions, it gives off heat. The water carries away this heat, thus preventing a runaway meltdown of the uranium, and also providing the steam that turns the turbines that generate the electricity. Like every other nuclear reactor in the world, the RBMK-1000 is designed to be totally safe. And it is, as long as nothing goes wrong.
At ten o'clock that Friday night Bohdan Kalychenko was also trying to get to sleep, under circumstances less favorable than Leonid Sheranchuk's. He was in a bunk in the fire department of the Chernobyl Nuclear Power Station. Kalychenko had borrowed the bunk from a fireman friend — well, definitely a fireman and at least a sort of a friend — named Vissgerdis, who was a member of the plant's Fire Brigade No. 2. The bunk had been constructed for someone a lot shorter than a man with Lithuanian blood like Kalychenko — or like Vissgerdis himself for that matter. Kalychenko had difficulty in composing himself comfortably in it. It wasn't merely the bunk; it was his job, his boss, his boss's bosses like Khrenov, his girl, his approaching wedding — it was also the fact that before being allowed to get to sleep he had been wheedled into two hours of cards with the rest of the firemen. Now he was eight rubles fifty kopecks poorer than he had been that afternoon, and his fiancee, Raia, was sure to find out that he had been gambling again.
He pulled the thin, sweaty blanket over his head to shut out the noise from the card game. It didn't work. It made it dark for him, but also hot; it did not keep out the men's voices from the next room, or even the reek of tobacco smoke from the game. It was Kalychenko's pride that he did not, at least, smoke. In fact, he was quite intolerant of people who did, like his fiancee — except that in her case it was useful to have her possess at least one vice he did not. It would be particularly valuable after they were married, he thought gloomily. At least, that was when he would need it most.
The idea of getting married was not all joy for Bohdan Kalychenko, Sooner or later, of course, it was what one did. But he was not ready for that sort of surrender, especially since he considered that it was entirely Raia's fault that she had become pregnant. Of course, he reminded himself, when they were married and had a room to themselves in the families' hostel, it would be quite nice to share a bed together every night — at least until the baby came, when one room would no longer seem quite enough for the three of them. And even in Pripyat there was a three-year waiting list for flats. To be sure, first there would be the honeymoon. . But even that, Kalychenko told himself sourly, would not be without its drawbacks. Raia was determined to go to the Black Sea. Neither of them had enough standing to get the plant or the union to get them into one of the special "sanitoria," so that meant paying seven rubles a day to some Crimean robber, and lucky if they didn't have six other beds in their room anyway.
He pounded the pillow, threw the blanket off, and sat up angrily.