Oconee. An individual in the general population who stands alongside the truck for five minutes could receive 1.3 mrem. If 10 members of the general public were so exposed during each shipment, the total annual exposure would be about 1.2 man-rem. Approximately 5 x 104 persons who reside along the 150 mile route over which the irradiated fuel is transported might receive a dose of 0.3 man-rem per year.*

The amount of heat released to the air from each cask will be about 10,000 Btu/hr. (For comparison, 35,000 Btu per hour is about equal to the heat released from an air conditioner in an average-sized home.) Although the temperature of the air which contacts the loaded cask is increased a few degrees, because the amount of heat is small and is being released over the entire transportation, no appreciable thermal effect on the environment will result.

C. Solid Radioactive Wastes

As noted in Section III.E.3, demineralizer resins and evaporator concentrates containing some radioactive materials will be shipped from Oconee. Under normal conditions, the individual truck driver might receive as much as 15 mrem per shipment. If the same driver were to drive 25 truck loads during the year, he would receive an estimated annual exposure of about 400 mrem. The total exposure of all drivers for the year, assuming two drivers with each shipment, might be as much as 1.4 man-rem.

If a person were near the truck for a few minutes, at an average distance of 3 feet, he might be exposed to as much as 1.3 mrem. Approximately 90,000 persons who reside along the 300 mile route over which the solid waste is transported might receive a dose of 0.3 man-rem per year. **

The cold fuel to be transported to the Oconee Units has been described in Section III.E.1. Under accident conditions other than

* In this case, the regulatory radiation level limit of 10 mr/hr at 6 feet from the vehicle was used to calculate the integrated dose to persons in an area between 100 feet and 1/2 mile on both sides of the shipping route. A speed of 200 miles per day and an average population density of 330 persons per square mile were assumed.

** This dose was calculated on the same basis as the dose to the people along the route from irradiated fuel.

accidental criticality, the pelletized form of the uranium fuel, its encapsulation, and the low specific activity of the fuel limit the radiological impact on the environment to negligible levels. Even for the higher radioactivity of plutonium recycle fuel, the form and encapsulation under credible accident conditions would limit the radiation effects on the environment to negligible levels.

The packaging is designed to prevent criticality under normal and severe accident conditions. To release a number of fuel elements under conditions that could lead to accidental criticality would require severe damage or destruction of more than one package, which is unlikely to happen in other than an extremely severe accident.

The probability that an accident could occur under conditions that could result in accidental criticality is extremely remote. In the highly unlikely event that criticality were to occur in transport, persons within a radius of about 100 feet from the accident might receive a serious exposure but beyond that distance, no detectable radiation effects would be likely. Persons within a few feet of the accident could receive fatal or near-fatal exposures unless shielded by intervening material. Although there would be no nuclear explosion, heat generated in the reaction would probably separate the fuel elements so that the reaction would stop. The reaction would not be expected to continue for more than a few seconds and normally would not recur. Residual radiation levels due to induced radioactivity in the fuel elements might reach a few roentgens per hour at 3 feet. There would be very little dispersion of radioactive material.

b. Irradiated Fuel

Irradiated fuel will be shipped from Oconee to a licensed fuel recovery plant as described in Section III.E.2. Effects on the environment from accidental releases of radioactive materials during shipment of irradiated fuel were estimated for the situation where contaminated coolant is released and the situation where gases and coolant are released.

(1) Leakage of contaminated coolant resulting from improper closing of the cask is possible as a result of human error, even though the shipper is required to follow specific procedures which include tests and examination of the closed container prior to each shipment. Such an accident is highly unlikely during the 40-year life of the plant.

Leakage of liquid at a rate of 0.001 cc per second or about 80 drops/hour can usually be detected by visual observation of a large container. If leakage of contaminated liquid coolant were to occur and should go undetected, the amount would be so small that the individual exposure would not exceed a few mrem and only a very few people would receive such exposures.

(2) Release of gases and coolant is an extremely remote possibility. In the improbable event that a cask is involved in an extremely severe accident such that the cask containment is breached and the cladding of the fuel elements penetrated, some of the coolant and some of the noble gases might be released from the cask. The probability of occurrence of such an accident is considered to be extremely remote.

In the highly unlikely event that such an accident were to occur, the amount of radioactive material released would be limited to the available fraction of the noble gases in the void spaces in the fuel pins and some fraction of the low level contamination in the coolant. Persons would not be expected to remain near the accident due to the severe conditions which would be involved, including a major fire. If releases occurred, they would be expected to take place in a short period of time. Only a limited area would be affected. Persons in the downwind region and within 100 feet or so of the accident might receive doses as high as a few hundred millirem. Under average weather conditions, a few hundred square feet might be contaminated to the extent that it would require decontamination (that is, Range I contamination levels) according to the standards) of the Environmental Protection Agency.

C. Solid Radioactive Was tes

As noted in Section III.E.3, about 45 truckloads of solid radioactive wastes will be transported each year from Oconee to a disposal site. The likelihood that radioactivity would be released as a result of waste being involved in an accident, lids on drums coming off, and some of the waste material getting outside of the drum is very small.

It is highly unlikely that a shipment of waste will be involved in a severe accident during the 40-year life of the plant. If it does happen that a shipment of low-level waste (in drums) becomes involved in a severe accident, some release of waste might occur but the specific activity of the waste will be so low that the exposure of personnel would not be expected to be significant.

Other solid waste from Oconee will be shipped in Type B packages, according to the applicant. The probability of release from a Type B package, in even a very severe accident, is sufficiently small that, considering the solid form of the waste and the very remote probability that a shipment of such waste would be involved in a very severe accident, the likelihood of significant exposure would be extremely small.

In either unlikely event, spread of the contamination beyond the immediate area is unlikely and, although local clean-up might be required, no significant exposure to the general public would be expected to result.

4.

Severity of Postulated Transportation Accidents

The events postulated in this analysis are unlikely but possible. More severe accidents than those analyzed can be postulated and their consequences could be severe. Quality assurance for design, manufacture, and use of the packages, continued surveillance and testing of packages and transport conditions, and conservative design of packages insure that the probability of accidents of this latter potential is sufficiently small that the environmental risk is extremely low. For those reasons, more severe accidents have not been included in the analysis.

VII. ADVERSE EFFECTS WHICH CANNOT BE AVOIDED

The construction of the Oconee Nuclear Station has caused 26,000 acres to be committed to use for an indeterminate length of time due to the clearing and flooding of the basins of the Keowee and Little Rivers. In addition, 3900 acres of farm and woodland have been set aside for the construction of transmission lines.

The following adverse effects can be expected in Lake Keowee. (1) Any organisms entering under the skimmer wall and unable to escape the current in the intake canal will be, depending on size, trapped against the screens or entrained in water circulating through the plant. (2) Some of the entrained organisms will be killed because of heat, impact, turbulence, or pressure change. (3) Only thermophilic attached organisms that tolerate low concentrations of dissolved oxygen will be found in the immediate vicinity of the discharge cove during the summer. (4) There will be a fluctuating outer bank or zone of the discharge plume from which mobile organisms will retreat as temperature and oxygen level become intolerable. (5) Epilimnetic organisms, particularly primary producers and consumers in the area in or near the plume, can be expected to fluctuate in species composition and biomass as temperatures and oxygen concentrations fluctuate. (6) Hypolimnetic and benthic species can be expected to decrease during late spring, summer, and early autumn as the cold hypolimnetic waters are pulled out from under the lake, heated, and discharged to the surface or intermediate layers.

In the Hartwell Reservoir headwaters, the dominant species will probably be those which can tolerate periodic surges of heated water released from the turbines of the hydroelectric station and survive under the changes in water elevation which occur from operation of the Keowee Dam (Section III.C.2.). Some entrainment of organisms will occur when the Keowee and Jocassee hydroelectric stations are operating or when the pumped storage facility at the Lake Jocassee hydroelectric station is pulling water up out of Keowee Lake.

The concentrations of most chemicals released, while adding to the existing amounts in Hartwell Reservoir, will be virtually undetectable and are not likely to be detrimental to fish species. In order to reduce any potential effect, chemical and radioactive wastes should be released only when the hydroelectric plant is operating. Effects from radionuclides released to Hartwell Reservoir are not expected to be distinguishable from effects, if any, induced by normal background radiation.