These lines are expected to be completed in 1973 or 1974. Only one-half of the distance of the lines to Site H and Newport is charged to the Oconee Plant.

The three units of the Oconee Nuclear Station will be essentially identical. Each will consist of a pressurized water reactor producing steam to drive a turbine-generator. Figure III-4 is a simplified diagram of one unit. A fairly detailed description of the nuclear steam system has been published.

One of the reactor units is described below.

The uranium fission chain reaction will occur only in the reactor core, a 12-foot-high close-packed array of fuel assemblies inside the reactor vessel. Each of the 177 assemblies will contain 208 fuel rods, consisting of cylindrical pellets of uranium oxide sealed within zirconium alloy tubes. The rate of the chain reaction will be controlled by neutronabsorbing metal rods that can be moved into or out of the core. Heat produced within the fuel rods will be transferred into water (actually a dilute boric acid solution) that will circulate up through the core. boron concentration in this primary coolant will be changed as necessary to adjust ("shim") the reactivity of the core. (Boron readily absorbs neutrons.)

The

When the reactor is operating at full power, heat will be produced at a rate of 2568 megawatts. Primary coolant water will leave the reactor vessel at 604°F and 2200 pounds per square inch; this pressure is high enough to prevent boiling on the fuel rods. The pressure is maintained by electrically heating a sidestream of water to the boiling point in a vessel called the pressurizer. A small amount of hydrogen gas is added to the pressurizer to aid in the recombination of any water decomposed by radiation in the fuel region. The hot primary coolant will pass through tubes in a steam generator, where it will transfer heat to water (secondary coolant) on the outside of the tubes. The pressure will be lower in the secondary system, and the water there will be converted to superheated steam at 570°F and 900 pounds per square inch. This steam will pass through a turbine, driving a shaft connected to produce electricity at a rate of 922 megawatts. be used within the plant, leaving a net electrical output from each unit of 886 megawatts.)

a generator which will
(About 36 megawatts will

In its passage through the turbine, the steam will expand and cool until it leaves as vapor at 80° to 100°F and at subatmospheric pressure. This vapor will be very pure water, which must be recycled. Recycling will require that the vapor be condensed to liquid water so that it can be pumped efficiently. Condensation will take place on the outside of tubes cooled by lake water being pumped through them. For each reactor unit, heat will be transferred from the condensing vapor to the cooling water at a rate of about 1650 megawatts.

Radiation emitted directly from the fission process will be absorbed in the reactor vessel and in the thick concrete shielding surrounding the vessel. The radioactive products of uranium fission will be almost entirely confined within the sealed fuel rods, but some may appear in the primary coolant because of leaks in a very small fraction of the 36,716 fuel rods. Part of the tritium generated in the fuel will diffuse through the cladding into the primary coolant, but more tritium will be produced directly in the coolant by reactions of neutrons with the dissolved boron. The primary coolant will also contain some corrosion products that have become radioactive by exposure to neutrons in the core. The secondary coolant (steam) will not become radioactive unless there is some inleakage of primary coolant to the secondary system in the steam generators. The reactor and primary coolant system for each unit will be housed in a cylindrical containment building, of reinforced concrete, designed to minimize the escape to the environment of any leakage from the primary system. Treatment of the primary coolant to remove corrosion and fission products and the handling of leakage are described later in the section on the radioactive waste system.

Each unit will be shut down periodically, and the reactor vessel will be opened for replacement of fuel assemblies in which the uranium has been depleted. Spent fuel assemblies will be transferred under water to a storage pool in a building adjoining the reactor containment building. After the radioactivity has diminished, the spent assemblies will be sealed in casks and transported offsite.

The units are generally similar to other pressurized water reactors currently under construction or already in operation. The Babcock and Wilcox Company is responsible for the design, manufacture, and delivery of the nuclear steam supply systems, the nuclear fuel, and the auxiliary and engineered safeguard systems. Babcock and Wilcox also provides technical direction of the erection of this equipment, assistance in operator training, and consultation for initial fuel loading, testing, and initial startup of each of the three units. The applicant is responsible for all other aspects of construction and startup and is also responsible for the coordination, scheduling, administrative direction, and operation of the power station once it becomes operational. The Bechtel Corporation is serving as a general consultant to the applicant to provide such engineering assistance as is needed during the design and construction of the Station.

The hydroelectric plant at Keowee Dam has an inlet at 735 feet above mean sea level. A weir, upstream from the dam, restricts the flow of water from the main body of the lake to that above 765 feet. The