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Mountains on the west. These rocks are generally recognized as being divided into four parallel northeast-southwest-trending belts in the Carolinas. From southeast to northwest these are the Carolina slate belt, the Charlotte belt, the Kings Mountain belt, and the Inner Piedmont belt. The site is in the northwestern (Inner Piedmont) belt.

The rocks of the site are geologically ancient and complex. Forces that folded and metamorphosed these rocks were associated with the formation of the Appalachian Mountains during the Appalachian Revolution, some 270 million years ago. These forces long since have died away and are no longer possible sources of earthquakes in this area. Faults and other lines of weakness dating from this Revolution may serve to locate present-day minor crustal movements which produce small earthquakes, and their location is of some importance. The most important is the Brevard fault zone that passes 11 miles northwest of the site. The design criteria for the Station, based upon earth shock considerations, took into account the nearest fault zone. Small earthquakes have been detected along this zone with intensities of IV to VI. On this scale of intensities, V and VI represent disturbances that can dislodge loose plaster, etc.; X, XI, and XII represent disturbances that are severely damaging. Epicenters for quakes (positions on the earth's surface directly above the maximum disturbance) are generally in fault zone areas. Besides the Brevard fault there are fault zones 30 to 200 miles southeast where quake intensities of VII or VIII have been recorded; because of their distance, these zones are of slight importance for the Station. By far the largest quake in this general area was the Charleston, South Carolina, earthquake of 1886, that had an intensity at the epicenter of X. This quake was felt over a wide area but was destructive only in the vicinity of the epicenter, 200 miles from the plant. No faulting was observed in connection with this shock; although the bedrock at Charleston is covered with a thick deposit of coastal plain sediment, and faulting might not show. F. ECOLOGY OF THE SITE AND ENVIRONS

The biota of that part of the Keowee-Toxaway project inundated by Lake Keowee was similar to the biota that at present dominates the area surrounding the lake, except that previously more stream-side communities were presents No species listed as endangered species by the Department of Interior inhabit the project area. Two forest types constitute the dominant vegetation of the Keowee-Toxaway area: (1) the intermediate deciduous forest which occupies the upland and mountain slopes and (2) the intermediate hemlock-hardwood forest found principally along the upper

river banks and sheltered coves. A relatively detailed listing of trees

and understory plants of the area was available. Some unusual plants known to occur locally include (1) a pennywort (Hydrocotyle americana), (2) a sundew (Drosera Rotundifolia), (3) mountain camellia (Stewartia ovata), (4) a milkwort (Polygala incarnata) which is rare outside the coastal plain, and (5) a filmy fern (Hymenophyllum tunbridgensa) which

is found nowhere else in the United States.

Oconee bells (Shortia galacifolia) are found principally in many coves in the upper reaches of the project. A stand of virgin timber, which includes 18 species of trees indigenous to the Appalachian area, has been set aside, along with 15 acres, as the Coon Branch Natural Area.

Faunal lists for the terrestrial areas of the project were not available. We have listed bird species (Appendix II-3) associated with the major tree species in an intermediate deciduous forest and an intermediate (7) hemlock-hardwood forest in the Highland area of North Carolina. These avian species are listed in order of abundance for the particular forest type. Most of these birds probably are found also in the Keowee-Toxaway Additional populations of migrant species of birds would be present in the region in spring and autumn.

area.

(8,9)

A list of probable mammalian species present in the area is presented in Appendix A-II, but since no mammalian inventories have been carried out by the applicant or its consultants it is impossible to confirm that all these species are present. Similarly, inventories for local species of amphibians, reptiles, invertebrates, or other fauna are available. Lists of possible species in various classes of these animals can be prepared but since specialized habitats are required for some species, such lists would be speculative.

Lake Keowee was filled early in 1971 and filling of Lake Jocassee is underway; so it is too early to expect comprehensive listings of typical lake biota or population data to be available as base lines for documenting later changes. However, a systematic inventory of biota should be under way or started immediately so that possible effects of the hydroelectricnuclear power complex can be studied for these aquatic ecosystems, which

will be going through a rapid ecological succession. A list18 21 fish

(Appendix

species found in Lake Keowee during August 1969 is available
A-II-11). No information was available on phytoplankton, emergent or
floating macrophytes (macroscopic vegetation), zooplankton, aquatic
invertebrates, reptiles, amphibians, etc. Inventories are necessary
to make in-depth evaluations of possible impacts on aquatic biota.
The applicant is undertaking further studies in this area and plans to co
continue the studies during plant operation.
(11)

Populations of diving and swimming birds (ducks, geese, grebes, etc.) on Lake Keowee apparently are not yet large, judging from on-site observations and information from the applicant, and low populations of these birds may continue unless plankton production increases or considerable emergent vegetation appears. A few shorebirds and wading birds were seen around Lake Keowee, and at least small populations of these birds can be expected to use the margins of the lake.

Hartwell Reservoir, not Lake Keowee, will receive the chemical and radioactive discharges as well as some of the effluent heat from the Oconee Nuclear Station. The environmental impact on Hartwell Reservoir is expected to be minimal (see Section V). Specific biological data for the Reservoir are desirable to further assess the environmental impact and to confirm that the impact will be minimal. In this connection, biological data on the Hartwell Reservoir have been requested from the Georgia Fish and Game Commission, the South Carolina Wildlife Resources Department and the Army Corps of Engineers.

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Because of the surrounding hilly terrain and its particular situation, the Oconee Nuclear Station is not readily visible for any great distance along main roads or from any population center. From the approach along highway S.C. 130, the location of a nuclear plant is advertised by an elevated spherical water tower with decorative rings representing a nucleus and electron orbits. On the hill nearby is a microwave relay tower with weather instruments. The buildings housing the reactors and turbines are partially hidden from the highway by the intervening higher ground (see Fig. III-1).

The paved road into the site leads to a Visitors' Center building of modern design, surrounded by appropriate landscaping as shown in Fig. III-2. The Visitors' Center is situated on a hill, with wide views of the lake and the buildings and switchyards of the nuclear station.

As shown in Fig. III-1, the three reactor buildings are cylindrical concrete structures 125 feet in diameter, and about 200 feet high with domed tops.

There are no tall stacks; gases are vented from pipes adjacent to and about the same height as the reactor buildings. The 900-foot-long turbine building and a smaller administration building adjoin the reactor buildings. The switchyards are located on relatively low ground near the turbine building.

The transmission lines leaving the plant on the east side are the most obvious sign of the power network.

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Power from the Station is transmitted via standard latticework transmission towers (about five per mile) to the applicant's network.

A minor exception is the use of steel poles with upswept arms for two miles in suburban North Greenville. The transmission lines that are attributable to the nuclear station are listed in Table III-1. The routing in the vicinity of the plant is shown in Fig. III-3.

About 3900 acres of land will be used for right-of-way by the transmission lines required for the power plant. Of the land in Oconee and Pickens Counties, about 27% is farmland; the rest is woodland.

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