Energy in Transition, 1985-2010 Final Report of the Committee on Nuclear and Alternative Energy Systems (1980) / Chapter Skim
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5 Nuclear Power
5 Nuclear Power
Pages 210-344
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From page 210... ...
. Policies for disposal of radioactive waste have not been developed, and delay in their development has heightened concern about the efficacy of proposed methods.
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The balance of the chapter takes up these items in detail.t SUMMARY Nuclear power contributes to diversity in the sources of energy on which the United States can draw. In 1978, 66 light water reactors (LWR'S)
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Source: Atomic Industrial Forum, E/ectriciry from Nuclear Power (Washington, D C: Atomic Industrial Forum, 1979) be unrealistically high.
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From page 213... ...
Translating these figures into nuclear power capacity, 2.4 million tons of U3Os would meet the lifetime fueling requirements of about 400 GWe of installed capacity, assuming the continued use of light water reactors on once-through fuel cycles. The total nuclear capacity in operation, under construction, or planned in the United States in 1979 amounts to 193 GWe 6 According to the Supply and Delivery Panel, the uranium production rates required to reach installed nuclear capacities much above 200 GWe by 2010 would demand a national commitment to uranium resource exploration and extraction.7 Further expansion and continuation of nuclear power could be accommodated if fuel reprocessing were permitted.
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From page 214... ...
Another possibility for a more durable industry is to switch from the present generation of light water reactors on the once-through cycle (no reprocessing or other reuse of spent fuel) to reactors and nuclear fuel cycles that make more efficient use of uranium.
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From page 215... ...
The thorium-233U fuel cycle can be used to greatest advantage in thermal advanced converters, and the uranium-plutonium fuel cycle can be used to greatest advantage in fast breeders. This suggests the possibility of using various integrated fuel cycles: combinations of fast breeders, advanced converters, and light water reactors.
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Much of the controversy has focused on the validity of risk assessments made in the Reactor Safety Study for the Nuclear Regulatory Commission (also known as the Rasmussen Report or WASH-1400)
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seems consistent with CONAES'S cautious, positive findings on reactor safety. Another element of public concern is apprehension about the ability of 'Statement 5-7.
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From page 218... ...
This concern is particularly acute for breeder reactors, which have little or no value without reprocessing, and it was this consideration that persuaded the Carter administration to defer both commercial reprocessing and commitment to the fast breeder. A possible advantage of the thorium-333U fuel cycle for fast breeders or advanced converters (it can be used in either)
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From page 219... ...
, and strengthened controls on fuel cycles can only be effected if the United States is an active participant, a reliable supplier of nuclear materials and know-how. These are arguments for carrying forward, and very probably exploiting, the development of reprocessing and breeder reactors, since both increase our ability to provide nuclear fuel.
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From page 220... ...
This contribution could be extended to about 600 GWe with reprocessing and recycle of fuel in light water reactors. A more complete assessment is needed of domestic and world uranium resources, and of the rate at which they can be produced at various costs.
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From page 221... ...
. The short-term health risks from routine operation of the LWR nuclear fuel cycle appear to be far below the risks from the coal fuel cycle.
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The most likely scenario by which nuclear power could contribute to nuclear armament is the appropriation of plutonium or MU from nuclear fuel cycles by a country that might not, in the absence of this opportunity, have made the decision to acquire nuclear weapons. RECOMMENDATIONS The committee's principal recommendations are listed below.
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From page 223... ...
Three advanced reactor types can be considered: the liquid-metal fast breeder reactor, the high-temperature gas-cooled reactor, and advanced versions of heavy water reactors. Of these, the LMFsR would be recommended if industrial economic factors were the only consideration.
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From page 224... ...
. Ore tailings and low-level radioactive wastes from the nuclear industry need a sound program of environmental protection to ensure that they do not present significant health risks to the public.
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In this quandary, any technical or industrial policy steps are, at best, supportive of larger national policy. All the antiproliferation measures we can conceive have an experimental character, including such relatively recent measures as the deferral of domestic plans for reprocessing and breeder reactors.
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From page 226... ...
Indeed, with only light water reactors on a once-through cycle (the most resource-intensive system) , cumulative ore requirements by 2010 would amount to just 1.2 million tons of U3O..
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From page 227... ...
Only those schedules that show early introduction and rapid installation of fast breeder reactors keep consumption and forward commitments of uranium oxide under 6 million tons by 2030. The simultaneous introduction and installation of advanced converters helps relieve some of the pressure on resources, but in all the cases illustrated, the demands on uranium, and possibly on thorium, exceed the rate of production the committee considers possible with present methods, as detailed in the section on uranium production.
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228 L 1 ,OOC 900 800 700 ~nr S(IC 40C o 3 30C r 200 .¢ 1 00 ~i 1,OOC `,< soa i_i z 70C 3 60C ,¢ 50C z 40C 30E 20C IOC ENERGY IN TRANSITION, 1985 2010 LP = LWR with PU Rccycic 1 = LWR + LMI-BR l:P = LWR wiOr PU Rccycic + LMI;BR H = LWR + HWR HP = LWR + HWR both with PU Recycic I T = LWR with Thorium Cycics + LMI:BR 250 .r :E 2.0U — r: 1 50 _ 500 ~ 467 7/ 0 — Advanced / / z 1 00 2s C ~ 0 7 5 — T~ 3O 00.52OS .. ~ 0.00 1970 1990 2010 2030 Yl AR Casc 1: Early ddvanced-reactor introduction ~.
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From page 229... ...
with reprocessing, along with reprocessing in LWR'S, could significantly extend the life of nuclear power within the uranium supply estimate of the Uranium Resource Group (1.8 million tons) through 2030 in case 2, late introduction of advanced converters oEers less extension time than case 1, but still more than lo years Advanced converters, introduced in 1995, reach an installed capacity of 20 GWe by 20 0 Source Adapted from E L Zebroski and B
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From page 230... ...
Table 5-1 shows the increase in estimates of reserves and probable potential resources since 1976. CONAES has adjusted its resource estimate, reflecting this increase, to 2.4 million tons of U3O, (excluding by-product recovery)
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: comparison of reactor types and cumulative ore requirements from 1972 forward. In all three cases, 2 4 million tons of uranium can sustain moderate rates of growth in installed nuclear capacity to 2010, with recycle of fissile isotopes in the selected mix of reactors in case 5, however, the late introducton of advanced conveners would realize significant savings in resource consumption only if the uranium resource base is more than 3 million tons.
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From page 232... ...
232 L = LWR LP = LWR with PU Recycle F = LWR t LMFBR 2ooor 1.800 1.61) 0 I ftnn _ 1 200 3 1 000 v i- 600 v v f~ :~ ENERGY IN TRANSITION 1985-2010 I~P = LWR with PU Recycle + LMI:BR H = LWR + HWR l:T = LWR with Thorium Cycles + LMI'BR 400 200 o i 732 ~ =8 w 2 o 2~ 4 o o 2 z 3 ~ O Total / _ \~/lWR's /ff 110188 - 866//~( //740'9 /7132 _ I' A ~ / Advanced _ / 125 1/ Reaclors 1 /r 1: 1 1 1 1970 1990 2010 2030 YEAR -1 ~ 1970 1990 ~' Yl AR lLLp ,/lyl' wf!
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Conditions can be met only by introducing fast breeder reactors and assuming abundant supplies of uranium 5 million tons for early introduction and rapid rates of installation. Source: Adapted from E
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From page 234... ...
A light water reactor requires at least 10 years to license and build, and the utility must be assured fuel at reasonably predictable prices for at least 10 full-power years of its 30-yr life. In planning for future advanced converters or breeders, the nuclear power industry will be particularly concerned that fuel is both available and producible at rates that correspond to the planned rate of buildup of the industry.
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From page 235... ...
Gaseous diffusion is itself energy intensive. On the average, a little over 5 percent of the electrical energy generated by a light water reactor is needed for the enrichment process.
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From page 236... ...
The three-plant complex operating in the United States has a capacity of 18 million swu/yr, and as of 1977 was intended to reach 28 million swu/yr in 1981.24 (Requirements have since decreased, and expansion has been delayed accordingly.) The expanded plants are expected to reach fullcapacity production by 1985 2s This expanded capacity has been committed to domestic and foreign obligations (323 GWe of light water reactors— two thirds in the United States and one third in foreign countries)
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From page 237... ...
A recent report points out that utilities holding long-term fixedcommitment contracts are required to provide uranium feed to the enrichment complex in amounts that may not agree with their fuel requirements, and it suggests that most of the apparent gap between production capacity and commitments could be eliminated through caseby-case adjustments 27 The substitution of fuel "ennched" by the addition of plutonium from reprocessed old fuel could also help prevent an "enrichment gap."3S Whether additional enrichment capacity will be needed beyond 1990, and if so when, depends on the number and type of reactors built and their particular fuel needs. Existing and planned enrichment capacity, for example, can supply the fuel for 215 GWe generated by today's light water reactors using a once-through cycle.
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From page 238... ...
Advanced converters on the thonumuranium cycle (such as the HTGR or LwsR) with fuel recycle have heavy requirements for highly enriched uranium for their initial critical loadings, but after the first loading, they use less separative work than AWRY 29 Breeder reactors started on plutonium have no separative work requirements and could indeed provide some fissile fuel (above and beyond what is needed to fuel new breeders)
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From page 239... ...
This would be done in recycling natural or slightly enriched uranium feel, using plutonium at low concentrations. This is the feel cycle for fast breeder reactors—at higher
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From page 240... ...
1995 or later 1 990 1995 Modification of designs: fuel cycle not developed Demonstration running: 1985: fuel cycle, related development in 1995 or later' Germany: fuel cycle partly developed Small experiment run: much more develop ment needed Many demonstrations in the United States and abroad Fuel cycle not developed Concepts only: borrows LhtFbF and HrGr technology 1995 2005 1 995 1 995 2000 - Based on the assumption of firm decisions in 1978 to proceed with commercialization No institutional delays have been considered except those associated with adapting foreign technology. On the basis of light water reactor experience, it can be estimated that it would take about an additional IS years after introduction to have significant capacity in place.
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ADVANCED REACToRs30 It has already been noted (Table 5-4) that the current generation of power reactors in the United States, consisting of light water reactors, is not very
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u ct o cd o o u .
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(Light water reactors operate at conversion ratios of 0.6 or less.) Breeder reactors can be designed to achieve conversion significantly greater than 1, although they could obviously be designed and operated at lower conversion ratios.
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From page 245... ...
The lifetime fuel requirements of a light water reactor on this fuel cycle could be 50 60 percent lower than those of an LWR on the once-through cycle, but the reactor would have to operate some time before enough 233U accumulated for reprocessing. Preliminary studies suggest that Th-U fueling of light water reactors would be uneconomically however, the relatively modest changes required represent the most immediate opportunity to begin learning the engineering of Th-U fuel cycles.
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From page 246... ...
HTGR'S appear capable of operating at both higher thermal efficiency and higher conversion ratios than light water reactors, but their expanded use depends on successful development of economical reprocessing for graphite-based fuel. If the high-temperature gas used to cool the graphite core could be used to dove a gas turbine directly, the thermal efficiency of this reactor could be further improved and the reactor's operation would be freed of requirements for water.
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has access to its technology. ECONOMIC PROSPECTS Capital Costs Under present economic circumstances, none of the advanced converters appears to be competitive with l.WR'S.
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From page 248... ...
than its light water counterpart (a PWR) 33; thus, this cycle is not listed in Table 5-4.
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From page 249... ...
would range from $500 $900/kg, and the cost of reprocessing fuel from fast breeder reactors (U-Pu) , from $300 $500/kg.
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. The savings from heavy water reactors are generally greater than those from HTGR S (see Table 5-4)
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From page 251... ...
Finally, HWR'S can operate on a denatured Th-U fuel cycle with relatively small concomitant production of plutonium—about one tenth that of an equivalent LWR. Among the disadvantages of heavy water reactors are that their capital costs appear high to evaluators in the United States, and that the plutonium produced in once-through operation is less contaminated with 238Pu and 240Pu, both isotopes that detract from the desirability of plutonium as a weapons materir..
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From page 252... ...
Fast breeder reactors obtain the fast-neutron spectrum by eliminating moderators such as graphite, water, or heavy water that slow down the neutrons emitted in fission to thermal energies before they produce additional fissions in the chain reaction. The fuel for fast breeder reactors is considerably more concentrated than the fuel for thermal reactors.
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From page 253... ...
plutonium production in the core, and with large production of 333U in a thorium blanket, which could be used to fuel advanced converters. Up to now, this possibility has not received much attention, perhaps because the necessary design changes would result in fuel that could not remain so long in the reactor, and because more frequent reprocessing would be required.
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From page 254... ...
Some concepts described above—such as LWR'S with improved fuel utilization, spectral-shift-control reactors, and LWBR'S represent extensions or modifications of light water reactor technology. The development of these concepts could rely heavily on existing industrial capacity and experience to reduce developmental requirements; similarly, the GCFBR could make use of LMFBR and HTGR technologies, if these continue to evolve at a sufficiently rapid rate.
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From page 255... ...
Our estimates for the earliest possible dates of commercial introduction for the principal breeder and advanced-converter designs, based on brisk efforts by government and industry, indicate that of the advanced converters, only the HTGR could have a commercial-size prototype operating before 1990. Of the breeders, the LMFBR could be readied for operation by the mid-199Os, and the GCFBR, 1O years later.
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From page 256... ...
. The world growth of nuclear capacity in conventional light water reactors exerts pressure on the United States to export some of its uranium or enriched fuel (or both)
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From page 257... ...
For example, the fuel produced by breeders would compete economically with natural uranium purchases, holding down the Mel cycle costs of converters; advanced converters would provide customers for breeder operators. Breeders might fit well, along with reprocessing and fuel fabrication plants, into a system of secure Mel cycle parks, while advanced converters could be located near existing load centers.
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From page 258... ...
Advanced converters would also be a useful adjunct to breeders in a breeder economy. Thus, conditions favorable to their development are also flexible.
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Such a design should be considered as the next major improvement of the heavy water line. As is well known, many decisions about the domestic nuclear power program have been deferred pending the outcome of the international Nuclear Fuel Cycle Evaluation.
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From page 260... ...
DOMESTIC ISSUES IN THE FUTURE OF NUCLEAR POWER PUBLIC APPRAISAL OF NUCLEAR POWER Public opinion polls have repeatedly shown that the majority of people in the United States view nuclear power favorably.44 Referenda introduced in seven states in 1976 that would have halted, postponed, or forestalled the expansion of nuclear power were all defeated. On April 7, 1979, just a week aher the accident at the nuclear power plant near Harnsburg, Pennsylvania, citizens of Austin, Texas, voted to retain their 16 percent interest in a nuclear power plant under construction, and they extended the city council additional borrowing authority to cover anticipated and unanticipated costs.
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From page 261... ...
. Release of long-lived radioactive effluents from the nuclear fuel cycle.
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It is obvious that a high level of confidence in nuclear power depends on consensus that the nuclear industry and the government have workable institutions to manage properly the whole enterprise, including the complete nuclear fuel cycle. COSTS OF NUCLEAR POVVER Nuclear power plants began to be installed in quantity in the late 1960s in response to (1)
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From page 263... ...
anticipated insecurity of oil supply. Nuclear power plants, in large sizes, appeared to be somewhat higher in capital costs than coal-fired plants, but the fuel cycle costs of nuclear plants were competitive with those of fossil fuels and had the added advantage that the price of uranium was considered much more stable than the price of fossil fuels.
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From page 264... ...
Capital Costs A number of studies have estimated the capital costs of nuclear plants. In particular, the costs of nuclear power plants have been compared to the costs of competitive electrical plants; in the short and intermediate term, this means specifically coal plants.
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From page 265... ...
There seems to be general agreement, therefore, that the capital costs of nuclear power plants are between S600/kWe and 5800/xWe in 1978 dollars, and those of coal plants are about the same to 20 percent less. Cost Escalation Estimates of future costs are colored by the estimators' expectations of cost escalations, over and above general inflation.
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From page 266... ...
This is offset to some extent by the difficulty of starting up and shutting down various plants, but the incentive remains to rule on nuclear plants more completely than on fossil plants for base loads. This effect suggested to early nuclear planners that capacity factors as high as 80 percent would be reasonable.
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From page 267... ...
New pricing policies, such as off-peak cost reductions, would promote this outcome. Higher capacity factors for both coal-fired and nuclear plants would improve the relative economies of nuclear power by decreasing the fraction of power cost represented by capital charges.
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From page 268... ...
Including associated chemical conversion, present cost is a little over 590/swu. In the past 3 years, enrichment charges have been tracking general inflation (after a threefold increase in 1975 to account for changes in government accounting of both capital charges and power costs)
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From page 270... ...
. For companson, Commonwealth Edisons7 lists nuclear fuel cycle costs in 1976 dollars of 6 mills/kWh (equal to 6.72 mills/kWh in 1978 dollars)
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From page 271... ...
The price has gone up because the capital costs of plants have been allocated to the users. The government was originally the main customer for separative 'Statement 5-21, by J
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From page 272... ...
A related set of costs may result from delays in licensing that add to the capital costs of plants under construction. These risks are subsumed under the capacity-factor projections and the contingencies included in construction schedules that are now part of the industry's standard accounting.
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From page 273... ...
For a light water reactor, the nuclear steam-supply system accounts for 10 20 percent of the total capital costs of the plant. The other 80 90 percent of the cost is for the so-called balance-of-plant, mostly conventional structures (piping, turbine, generator, condenser)
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From page 274... ...
1.03 TOTAL 7.6 3.2 aNot included, but assumed identical. Table 5-9 compares projected fuel cycle costs for an LMFBR and LWR (with uranium and plutonium recycle)
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From page 275... ...
According to these data, if both coal and nuclear plants are run at 70 percent capacity factor, and particularly if the best available emission control technology is required for coal plants, nuclear power is cheaper in most regions of the United States. However, if nuclear plants are run at capacity factors around 55 percent and coal-fired plants at around 70 percent, with no new emission control technology required, coal-generated electricity would be cheaper.
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From page 276... ...
Burlap in megawatt-days per metric ton: 33,000 tar pressurized-water reactors and 29,000 for boiling-water reactors.
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From page 277... ...
Nuclear Power 10 _ .~ _ ~4 ~ 277 1 985 -- -- _ ,__ ~ ~ ~ 1 _ ~ ~ _ ~ a _ ~ _ ~ _ =~ REGION lor O o £ C; 8 __ _ ___ 2000 REGION Regional Coal-Fired Generation Costs; Environmental Regulations in Effect in 1977 '~7 incremental Cost Resulting from Requirement to Use Best Available Pollution Control Technology Nuclear Power Cost; 55 Percent Capacity Factor -- -- -- Nuclear Power Cost; 70 percent Capacity Factor FIGURE 5-7 Comparison of coal-fired and nuclear power costs under existing and proposed environmental regulations. Source: D
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From page 278... ...
The decision for or against the ultimate possibility of a breeder economy will have a profound effect on decisions about other reactors— LWR'S in particular—but advanced converters as well, since breeders would help hold down future uranium demand and cost. REGULATION OF NUCLEAR POWER PLANTS The regulatory process affects the industry by lengthening the time between planning a new generating facility and placing it in operation, by retroactive changes in plant design arising from the unique surveillance responsibility of the Nuclear Regulatory Commission, and by providing a special forum for public opposition to nuclear plants.
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From page 279... ...
The involvement of the Nuclear Regulatory Commission in events following the accident at Three Mile island is widely credited as decisive in maintaining confidence that a nuclear accident need not lead to public catastrophe. In streamlining regulation of the nuclear power industry, therefore, close attention to the objective requirements of protecting the public must be maintained, as well as attention to the requirements of public confidence: legitimate participation in technical decisions and observance of due process.
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From page 280... ...
We have adopted the GWe-year of reactor operation as the unit of system operation, since this gives some insight into the risks associated with a single large nuclear power plant. Actuanal risk, of course, says nothing about the distribution of risk (for example, among
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From page 281... ...
3. At various stages in the nuclear fuel cycle, radioactive effluents are discharged.
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From page 282... ...
In this respect, light water reactors are inherently self-regulating. An interruption of coolant flow could, however, be brought about by a break in the coolant-flow line a loss-of-coolant accident (LOCA)
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From page 283... ...
Using an analytical technique called fault-tree analysis, the Reactor Safety Study (also referred to as the Rasmussen Report or WASH-1400) 66 has estimated the expected median frequency and consequences of various accidents in light water reactors of contemporary design 67 The method consists of analyzing failure rates of various components in the operating reactor system (including operator failure where appropriate)
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From page 284... ...
The engineering protocol of basing such judgment on "conservative" or worst-case analysis is almost automatic, and it is claimed that much of the translation was on this basis. A degree of conservatism that has been documented since the time most antiques were filed can be found in the assumptions made about the rate of heating of uncooled reactor fueler and about the release of fission products from melted ffiel.99 it is now believed that a "best value" assumption of the heat input would imply delayed onset of meltdown and a lengthier period over which meltdown might occur, significantly improving the likelihood of corrective action.
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From page 285... ...
A number of organizations, including the Atomic Energy Commission, the American Physical Society, the Environmental Protection Agency, and the Union of Concerned Scientists," identified a number of omissions, errors, and additional sources of uncertainty in the report. The Nuclear Regulatory Commission responded to these criticisms by commissioning the Risk Assessment Review Group.
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From page 286... ...
The product of this 1in-1000 figure and the estimated probability for meltdown of I in 20,000 per reactor-year gives the much-quoted WASH-1400 estimate of the probability of severe accidents in light water reactors: I in 2 million per reactor per year. The Reactor Safety Study can be used to draw certain inferences, in spite of the large uncertainties that must be attached to the frequencies at which accidents of various consequences might occur.
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From page 287... ...
33 ~s m u u 0 0 -z J ~ E o o o ~ ~ _ a ~ - E I og ~ ° ° o | = 0 E — o °.
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From page 288... ...
c o .— o c ou c o c c c i~i e o ~: o ~n OC, ~ O -~ CO O C ~ 0~ Ye E o C ,g A C E o o :` o ~a = 8 C e _ _ ~, o_ g 1 oooo oo ~ _ o o 1 oooo o' o 8 ° g 1 oooo 1 1 1 1 1 1 1 1 1 1 1 o~=o oooo mr~= g o o o o o o o o o _ rl o~ ~ 1 ~oo ~ C C o C o 9—E E o' o o o C .9 .9 .9 .9 .9 = C C C C 00000 C ~ ~ .
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From page 289... ...
The analyses require information that has not yet been assembled for advanced converters or fast breeders: specific designs, recognized design criteria, and results of accident analyses. The only document produced in the United States on the safety of LMFBR'S and available for study is the draft environmental statement for the Clinch River breeder reactor.
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From page 291... ...
This represents a significant safety advantage over light water reactors. Potentially severe accidents that are physically possible, but so extremely improbable that it is not considered reasonable to counter them by expensive engineered safeguards or consider them in siting decisions, fall into class 9.
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From page 292... ...
The HTGR has demonstrably better tolerance for storing decay heat without releasing fission products and may be less subject to a large LOCA, but it has the extra mechanism of graphite oxidation for potential release of fission products and heat in case of loss of the helium coolant, for example, air could not be used for emergency cooling because it would burn up the graphite. 9 Sabotage of Nuclear Facilities As already noted, deliberate sabotage has not been included in the discussion of nuclear accidents, as it is not usually included in accident analysis of other systems.
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From page 293... ...
Thus, with regard to vulnerability against loss of generating capacity, nuclear plants must be rated as highly secure. With regard to vulnerability against attacks or threats aimed at endangering the public, nuclear plants have considerable intrinsic protection.
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From page 294... ...
~ As with many other large industrial installations, it would appear that the greatest degree of defense against sabotage should be concentrated at sites near large population centers. The Nuclear Regulatory Commission is responsible for plant protection standards and appears to have given the matter of sabotage adequate emphasis.
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From page 295... ...
In the case of the United States, this institution is the Nuclear Regulatory Commission. For international concerns, such bodies as the international Atomic Energy Agency (lAEA)
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From page 296... ...
. The safety of new reactor types, such as LMFBR'S or advanced converters, should be compared with the safety of existing reactors.
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From page 297... ...
(See chapter 9.) Other materials—fission products, higher actinides, and activation products—have no natural source of any consequence.
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From page 298... ...
The first is to package and isolate the wastes as well as possible, and the second is to arrange for sufficient delay and dilution, in case the isolation fails, to ensure that the concentration possibly returning to the biosphere is not a major source of risk by prevailing standards. The most radioactive materials (e.g., most fission products and most products of neutron activation)
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From page 299... ...
A standard light water reactor requires the mining of about 150 tons/yr of U3OS, and at the typical concentration of 0.1 percent in the ore, this amounts to about 150,000 tons of rock, or about 40,000 yd3 (30,000 ma)
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From page 300... ...
The most troublesome is 99Kr, which is to be collected and stored for about a century when the amounts become significant. Tables 5-14 and 5-15 set out, respectively, concentrations of chemical elements in spent light water reactor fuel and the radioactivity of important nuclides.
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From page 301... ...
Looking to the future, we can expect to see a large increase in the generation of alpha-active waste if 233U and plutonium are recycled. A considerable amount of waste is generated during nuclear fuel fabrication: dusts from grinding operations, contaminated fabrics from filters, contaminated crucibles and tools, contaminated metal pieces from rejected fuel elements, and so on.
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From page 303... ...
8 8 ''' ~ ~ c .o ~ g ~ ~ O OD ~ or _ 0 ~ g ~ ~ ~ ~ ~ ~° 8 rat ret ~ ~ ~ _ ~ ~ ~ 0 ~ c ~ E E ~ z ~ ~ y y ~ ~ 9 = c ~ ~ ~ ~ o~ ~ o ~ .
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From page 305... ...
~ ~ ~ o 0 0 ~ ° ° ~ ° ~ 0 ~ oo O ~ ~=o ° ~ 0 ~OD o ,- - - ~ ~ o )
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From page 306... ...
Leaks at Savannah River have been minute, and zero at West Valley, but the local hydrology is by no means so favorable in those two places as in Hanford. Spent Fuel as Waste President Carter announced in 1977 that the United States would defer reprocessing of spent reactor fuel indefinitely, to avoid potential diversion of reprocessed plutonium for weapons.
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From page 307... ...
protects against subnational diversion because the spent fuel is literally too hot (radioactive) to handle.
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From page 308... ...
: 13C + In ~ 14C AN + in ~ 14C + IH Similarly, if all the tritium produced in LWR fuel from a 2000-GWe world industry were released, the dose to each individual would reach a constant value of about 0.03 person-rem/yr after about 20 years; further additions to the environmental inventory would be balanced by its decay. The widespread use of heavy water could significantly increase the quantity of tritium formed, due to the following reaction.
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From page 309... ...
To relieve utilities of the responsibility for storing increasing amounts of spent fuel in their temporary cooling ponds, the government proposed in 1977 to accept title and transfer of spent reactor fuel on payment of a one-time storage fee." At least for the time being, the stowaway fuel cycle will prevail, and the high-level waste process will involve early storage of discharaged spent fuel in water-filled canals at the reactor site (to provide gamma-ray shielding and a medium for heat dissipation) , later encapsulation of the unprocessed assemblies in sealed containers, and delivery of canned assemblies to the government for storage.
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From page 310... ...
The resistance to leaching of the glass and the absence of groundwater serve only as "insurance" factors. This question has recently been reviewed by the Amencan Physical Society (APS)
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From page 311... ...
In some settings, however, this problem may cause deep drilling to be a preferred technique over excavation of a mined cavity; for example, when the integrity of the rock above the cavity is uncertain. The Nature of the Waste Disposa/ Hazard An informed public response to the hazard presented by stored radioactive waste must begin with a qualitative understanding of its nature.
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From page 312... ...
The plant size usually considered to be of full commercial scale would handle 1500 tons of spent fuel per year, the annual throughput from about 50 GWe of LWR 5. The fission products handled would be many times greater than at Savannah River, and there would be orders of magnitude more plutonium and higher actinides in the waste.
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From page 313... ...
. Thus, only the longer-lived radioactivities, primarily actinides and a limited number of fission products such as technetium-99 (99Tc)
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From page 314... ...
Some Social and Institutional Considerations Understanding the problems of nuclear waste management requires discussion of more than the technology. The decisions to be made are principally of a social nature, such as how safe is safe enough?
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From page 315... ...
In the meantime, spent fuel from existing nuclear plants was temporarily stored in water basins ·See statement 5-32, by L
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From page 316... ...
To expect confirmation by experiment of expectations for integrity beyond 1000 years is simply impossible. Our own conclusions and recommendations are essentially identical with those reached by the American Physical Society's study group on nuclear fuel cycles and waste management, with regard to the feasibility of radioactive waste isolation.95 Among other points, the study group notes that waste isolation is feasible in salt and other media; that detailed technology for waste solidification, encapsulation, transport, and emplacement in mixed salt caverns is within the scope of existing knowledge; that confidence in geological isolation arises primarily from limitations on the rate of ion migration in underground formations; that continued investigation of geological and geochemical transport modeling is the most important current research topic; and that unreprocessed spent fuel should not be considered as waste, at least at this time.
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From page 317... ...
The current policy, which gives localities and states arbitrary veto power, seems to be unworkable because local opinion has proved particularly vulnerable to scare tactics. The potential for the future development of improved methods of dealing with radioactive wastes should not be ignored.
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From page 318... ...
SAFEGUARDING THE DOMESTIC FUEL CYCLE Atomic bombs are made from fissile material, and fissile material is the fuel of nuclear power. The term "safeguards" is the rubric under which we collect all the measures by which the manufacture of bombs from nuclear fuel materials can be prevented.
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From page 319... ...
The recycle of this material in breeders or advanced converters could markedly reduce the need for mu from nature. However, both MU and 939Pu can be made into bombs.
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From page 320... ...
Radioactivity of Reprocessed Fuel Recovered uranium from slightly enriched reactor fuel has more 233U than natural uranium, but after purification from fission products and plutonium, it can still be handled essentially as virgin matenal. Recovered thorium is highly contaminated with 223Th and its radioactive daughters.
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From page 321... ...
The chief drawback with denatured 233U is the effect of depleted uranium (MU) on nuclear fuel cycles.
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From page 322... ...
Denatured fuel cycles require further study before definitive conclusions can be drawn. The heavy water reactors, HTGR'S, and LWBR'S appear the most likely candidates for denatured fuel application.99 The denatured Th-U cycle does not appear attractive for conventional LWR'S.
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From page 323... ...
Finally, the Civex cycle requires colocation of reprocessing and fabrication facilities to minimize shipment of radioactive matenal, and this is a highly desirable antidiversion practice in itself. However, it must also be noted that wastes from the fabrication of Civex Mel (in contrast to the alpha-active wastes from fabrication of ordinary nuclear fuels)
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From page 324... ...
The fuel must be loaded onto a vehicle for shipment; the vehicle could be hijacked, misplaced in railroad systems, or waylaid. Some maintain that shipments of nuclear fuel must be accompanied by unusual security measures.
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From page 325... ...
There is some disagreement as to how large such an attacking force might be, but a report of the Nuclear Regulatory Commission suggests that an on-duty force of about a dozen guards, properly equipped and with reinforcements available, would be sufficient to protect a nuclear facility such as a reprocessing plant.~°~ This is judged to be a competent group to defeat a small attacking force or to delay a large one until reinforcements could be brought in. The other condition is that the security force and key operating personnel (particularly, managers and professional employees)
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From page 326... ...
We must therefore expect that different countries will evolve different internal safeguards, and we should avoid judging these safeguards by too detailed comparisons with our own. NUCLEAR POWER AND PROLIFERATION OF NUCLEAR WEAPONS The view is increasingly expressed that the most serious liability of commercial nuclear power is the link between this technology and the international proliferation of nuclear weapons.
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From page 327... ...
The motivations of nations to acquire both nuclear reactors and nuclear weapons are as much an issue as the technical means, and those motivations arise from concerns for the security and independence of energy supplies, trustworthiness of military alliances, regional antagonisms, disparities in arsenals of conventional armaments, aspirations to greater status in the community of nations, and perceptions of rich-poor, big-small, and north-south inequities. It is this complexity and diversity on the motivational side that led one analyst to insist, "There are no simple solutions that are feasible, no feasible solutions that are simple, and no solutions at all that are applicable across the board."' 06 How should concern for proliferation influence the use of nuclear technology in the United States and shape the action this country takes to help or hinder the use of nuclear power technologies abroad?
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From page 328... ...
reluctance to commit the necessary technical and financial resources to this particular task; and (4) lack of the means to acquire the necessary fissile materials, which until recently only a few nations have had the technical wherewithal to obtain.
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From page 329... ...
is separated from the highly radioactive fission products in a form that requires no further isotopic separation for use in nuclear bombs. One argument against a strong link between nuclear power and proliferation holds that nuclear weapons can be manufactured by a number of methods that are far less costly and troublesome than trying to use nuclear fuel cycles.
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From page 330... ...
The spread of nuclear technology has been accompanied by general acceptance with some outstanding exceptions of IAEA safeguards and the Non-Proliferation Treaty. The terms of the treaty and safeguards explicitly offer favorable status for nuclear energy development as a reward for nonproliferation, an apparently effective bargain.
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From page 331... ...
IS THE INFLUENCE OF THE POSITION OF THE UNITED STATES ON NUCLEAR POWER VERY IMPORTANT? Again the spectrum of opinion can be illuminated by considering three answers to this question: yes; yes, but only if the position of the United States is one of continued active participation in the world nuclear power market; and no, regardless.
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From page 332... ...
Since the treaty requires that weapons states cooperate with non-weapons states in making available the technology for peaceful applications of fission, the United States could not withdraw from the international nuclear market, and perhaps cannot even limit selectively the export of particularly proliferation-prone technologies without weakening support for the treaty among non-weapons states. The unequivocal "yes" viewpoint—that the United States can exercise influence against proliferation through its position on exports of nuclear technology, on the one hand, and through the character of its own nuclear energy supply, on the other—rests on three propositions.
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From page 333... ...
Business as usual in the country with the biggest nuclear industry in the world can only be taken as a clear signal for business as usual everywhere. The more the United States pushes nuclear energy at home, particularly plutonium recycle and plutonium breeders (which are claimed by some to be more subject to proliferation than other technologies)
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From page 334... ...
2. Among those approaches dealing with nuclear power, seeking increased resistance to proliferation in the characteristics of reactors and fuel cycles, versus developing management techniques and institutional arrangements for nuclear power that act against proliferation.
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From page 335... ...
The United States could choose, in its own relations with recipient nations as a supplier, to reach safeguards agreements more stringent than those enforced under the treaty. One such possibility is to lease nuclear fuel to non-weapons states rather than selling it, requiring return of the fuel, when spent, for reprocessing or storage without reprocessing in this country.
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From page 336... ...
A politically much more difficult, but also more promising, approach to proliferation control is to place the most sensitive parts of the fuel cycle under international control, including enrichment plants, reprocessing plants, plants for the fabricating of plutonium fuel, and shipping links wherein plutonium flows unprotected by accompanying fission products. Breeder reactors using undenatured fuel would perhaps also come under international control.
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From page 337... ...
But critics who think the proposals too mild assert that continuing to export reactors themselves will encourage the owners to complete a measure of energy independence by seeking, as quickly as possible, domestic enrichment or reprocessing capacity, or both, and critics who think the proposals too severe believe that resentment of moralizing from the United States on these matters will diminish any influence we might have had in securing better international safeguards for the full range of nuclear facilities sure to be demanded almost everywhere. If the United States were to go further than the Administration's proposals by trying to erect barriers against the spread of all nuclear technologies, it seems clear that, for consistency, domestic policy would have to phase out nuclear power, and foreign policy would have to assist other countries with a variety of alternative energy supplies.
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From page 338... ...
therefore, that individuals with different perceptions of the likely future behavior of governments, of the incremental dangers of risk reduction associated with given technological changes, and of the likelihood and jeopardy of energy shortages, do not agree whether the United States should try to accelerate or decelerate the use and spread of nuclear power in general and breeder reactors in particular. We do agree that any proposed policy should recognize the possibility that it is based on wrong judgments, and accordingly, should incorporate escape routes—ways to pull back from a policy decision if evidence accumulates that the consequences run counter to its aims.
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From page 339... ...
; U.S. Nuclear Regulatory Commission, Final Generic Environmental Statement on the Use of Recycle Plutonium in Mixed Oxide Fuel in Light Water Cooled Reactors, vol.
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From page 340... ...
In addition to the references cited for this section, the interested reader is referred to the files of the journal Nuclear Engineering International for descriptive articles on most of the important reactor types and prototypes 31. There is a strong program now investigating "improved" light water reactor fuel cycles.
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From page 341... ...
39 For example, two such reports are "Repon to the American Physical Society by the Study Group on Nuclear Fuel Cycles and Waste Management," op. eit, and ft;asuen et a/, ap cit.
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From page 342... ...
65 Decay Heat Power in Light Water Reactors, ANS-5.1 Proposed Standard. Amencan Nuclear Society, June 1978 66.
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From page 343... ...
85. "Repon to the Amencan Physical Society by the Study Group on Nuclear Fuel Cycles and Waste Management," op.
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From page 344... ...
95. "Report to the Amencan Physical Society by the Study Group on Nuclear Fuel Cycles and Waste Management," op cit.
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Key Terms
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