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The fuel load is a major factor in the economics of fuel processing. From an analysis of power reactors and their fuel discharge, it appears that about 100 metric tons of uranium per year, as slightly enriched uranium dioxide fuel in stainless steel or zircaloy tubes, will be the fuel load for the next 5 years from private and Government reactors in the United States. One small-scale plant is said to be capable of handling 74 metric tons of uranium per year. According to the authors, two or three small plants would provide the means for private in. dustry to enter the business without excessive risk in a changing market and with a chance of modest but increasing profits. Furthermore, such an entrance into the processing field could provide the competitive stimulus necessary for healthy evolution of the nuclear industry. Cost comparison of two methods for preparing fuel for processing

A cost comparison has recently been made by Adams and others at Oak Ridge on two different methods of head-end treatment for preparing irradiated fuels for processing. The methods compared are the mechanical shear-leach process and the aqueous Sulfex decladding process. The comparison was made for a typical power fuel, consisting of stainless-steel-jacketed uranium oxide. The mechanical process, in which the fuel is chopped into short lengths and the exposed core is leached with boiling nitric acid, has been adopted for the proposed privately owned NFS plant. In the Sulfex process the stainless steel jacket is dissolved in sulfuric acid and discarded, and the exposed core is dissolved in nitric acid.

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This economic comparison is based on a processing rate of 800 metric tons of uranium per year and shows that both capital cost and operating cost are lower for the mechanical process.

Another important difference between the two head-end methods is in the volume and type of waste produced from the fuel cladding. The cost of handling and storing the decladding waste from the Sulfex process was estimated as $12 per kilogram of uranium processed, whereas the cost for the cladding waste from the mechanical shear process was estimated as $0.59 per kilogram of uranium processed. If the shear process is used, most of the radioactive material remains fixed in the cladding metal, greatly decreasing the possibility that radio active nuclides will escape to the biological environment.

Criticality hazards present a much greater problem in the continuous conveying and leaching equipment of the shear-leach method than in the Sulfex batch dissolvers. In continuous equipment the possibility of concentration transients in the liquid phase due to changes in the rate of leaching of sheared and crushed fuel causes greater concern about the possibility of a nuclear excursion, A greater safety factor may therefore be needed in the design of the continuous conveying and leaching equipment to attain the degree of reliability that the simpler Sulfex batch dissolver has.

TRANSPORTATION OF IRRADIATED FUEL

By early 1963 the transportation of spent fuel from nuclear power reactors is expected to begin in appreciable volume. Several firms are offering a complete fuel-transport service including cask rental, maintenance and inspection, arrangement and supervision of transportation, and the performance of regulatory paperwork."

GJ. B. Adams, A. M. Benis, and C. D. Watson, "Comparative Coat Study of Processing Stainless-Steel-Jacketed UO2 Fuel: Mechanical Shear-Leach Versus Sulfex-Core Dissolution," USAEC Report ORNL-3227, Oak Ridge National Laboratory, Apr. 23, 1962.

? Nucleonics, 20(10): 26–27 (October 1962).

Fuel-transport service for the NS Savannah and for the Dresden nuclear plant will be provided by the Stanray Corp. Both reactors will be serviced by the same 70-ton cask mounted on a specially designed rail car. The cask contains six fuel cavities, each cavity being capable of carrying four Dresden fuel assemblies or one NS Savannah fuel assembly. The 14-foot-high cask uses an internal water cooling system backed up by a secondary natural-convection water system. It was learned in a private communication that the first ship ment from Dresden is scheduled for February 1963.

Spent-fuel transport for the Yankee reactor will be provided by Westinghouse using a 70-ton cask designed by Edlow Lead Co. This cask has a duplicate cooling system and a standby power source. The first Yankee shipment was scheduled for around November 1962.

Fabrication of a prototype cask to be used for the Piqua, Ohio, and the Elk River, Minn., reactor fuel elements has been started by Knapp Mills. In this cask the conventional cooling- and heat-dissipation equipment has been eliminated. Instead, Knapp Mills has developed fuel-assembly baskets capable of carrying the heat to the cask's inner shell by conduction. A special alloy of high thermal conductivity used for the baskets also includes neutron poisons for criticality control. Maximum heat-transfer efficiency is achieved by metallurgically bonding lead to the inner and outer shells of the cask. Weighing only 28 tons, the cask will carry 19 Piqua or Elk River fuel elements and is said to have the highest capacity yet achieved in terms of fuel elements per ton shipped.

Other firms offering fuel-transport services include National Lead Co., which is preparing to service the Battelle Memorial Institute research reactor, and O. G. Kelley & Co., which has built eight 70-ton casks for the Savannah River plant (SRP) and one 60-ton cask for the Canadian AEC.

Under a Euratom study & the Edlow Lead Co., is preparing procedures for shipping spent fuel from Euratom nations the United States for processing. The study includes planning of routes and methods of transport, definition of required regulations and documentation, and determination of the range of costs involved. Similar studies on spent-fuel shipment have been conducted under Euratom contracts by the Stanray Corp., and by the French Groupe d'Études Nucléaires Lebon-Sogei.' The Edlow Lead Co., in association with several European firms, has indicated that it is prepared to offer a complete service for Euratom fuel shipments. This would include the manufacture of casks for sale or lease, the transport of shipments to designated European ports, the monitoring of shipments on arrival at U.S. ports, and the supervision of port handling and rail or road transport. According to AEC, port clearances have been obtained for several U.S. seaports in preparation for forthcoming foreign shipments of spent fuel.

The AEC is attempting to develop practical criteria to govern the shipment of highly radioactive materials, such as spent fuel elements. Drop, puncture, and fire endurance tests are being conducted by several organizations, including Franklin Institute, Underwriters Laboratory, Oak Ridge, Hanford and Savannah River. Some of the test data are under study and evaluation."

In order to provide some guarantee that reactor fuel casks have a high degree of integrity to the high-impact loading that could result from a transportation accident, AEC's proposed fuel-shipping regulations specify that a cask must maintain its shielding integrity after a 15-foot fall onto a solid unyielding. object. Since data on possible cask damage cannot be calculated with any degree of certainty, data are being obtained experimentally at Oak Ridge on inexpensive small-scale models and should permit scale up to actual cask sizes. All the cask models have an inner and outer steel shell and a lead-filled annulus.20 In these tests the casks are instrumented. Compressometers indicase the maximum deflection in the cavity at impact, and accelerometers, measure the deceleration at the location on the cask where they are attached. Inertia switches that are present to function under a certain shock load are used to check the information obtained from the accelerometers. Strain gages measure the strain at points of interest.

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9 The Joint Research and Development Program Quarterly Digest, “Euratom-U.S. Agreement for Cooperation," July 1-Sept. 30, 1961, 1(4): 45.

20 Oak Ridge National Laboratory, Chemical Technology Division annual progress report for period ending June 30, 1962, USAEC Report ORNL-3314, Sept. 21, 1962.

Casks have been dropped in various positions and from various heights. Aftercasks of several sizes are dropped, the data will be correlated to determine whether the results obtained from model testing can be satisfactorily scaled up. to help in setting some of the important parameters in cask design,

In another study at Oak Ridge, data on the probable temperature rise due to. fission-product decay heat in spent fuel elements during shipping were obtained with electrically heated fuel rods. The simulated fuel bundles studied con-. tained 4 to 64 tubes and were heated in air-filled casks 24 inches long and either 12 or 16 inches in inside diameter. By assuming that the bulk of the heat is transferred by radiation, it was generally possible to predict the temperatures of the center pins within 20° C. at pin temperature 10 between 200 and 300° C.

WASTE DISPOSAL

In September the AEC amended the license of Nuclear Engineering Co., Inc., Pleasanton, Calif., to permit the company to bury low-level radioactive waste at an 80-acre site in the Amargosa Desert, approximately 11 miles southeast of Beatty, Nev. 11 12 This land is owned by the State of Nevada, which is leasing it to Nuclear Engineering for this purpose.

This would be the first license issued by AEC for commercial burial of radio active waste on State-owned land. The Commission's regulations provide that: persons engaging in commercial land burial of low-level wastes must do so on. Federal or State-owned land. This is to assure necessary long-term control of the land. Officials of the State of Nevada and Nye County, where the proposed burial site is located, have approved the proposed license.

The typical low-level waste to be buried by Nuclear Engineering includes: slightly contaminated glassware, paper wipes, ashes, and laboratory paraphernalia. It does not include high-level radioactive waste. Under the proposed license, Nuclear Engineering would bury only packaged solid wastes in approved containers. The actual burial of these wastes will be made in 100-by-50-foot'

. trenches excavated to a depth of 20 feet. Packages of solid wastes will be stacked in the trench, and there will be a minimum of 3 feet of earth covering thelast layer of packages. The radiation level at the surface of the ground will be negligible because of the low radioactivity level of the materials and because of the shielding provided by the earthfill.

The Nevada facility of Nuclear Engineering will include a building with 10,000 square feet of floor space. The building will be subdivided into an office area, laboratory area, packaged-waste-storage area, and waste-processing area. Processing and burial activities initially will be carried out in a 40,000-squarefoot area of the 80-acre site. This area will be enclosed by an 8-foot-high fence.

Nuclear Engineering will have adequate radiation-detection instruments, airsampling devices, and personnel-monitoring devices at the facility. The company has drilled a test well on the site, from which it will obtain periodic water samples to determine whether there has been any increase in radioactivity in the ground water due to burial operations.

In October this same company was licensed by the State of Kentucky to bury low-level waste at a site near Flemingsburg, Ky.

10 See footnote 10 on p. 217. U “AEC Proposes To Permit Burial of Low-Level Radioactive Waste at Site in Nevada,". AEC press release E-286, Aug. 17, 1962. 12 H. B. Atkinson, USAEC,

private communication, Dec. 6, 1962.

APPENDIX 6

REPORTS FROM THE ADVISORY COMMITTEE ON REACTOR SAFEGUARDS

ADVISORY COMMITTEE ON REACTOR SAFEGUARDS,

ATOMIC ENERGY COMMISSION,

Washington, D.C., October 11, 1962. Subject: Report on Nuclear Fuel Services, Inc. Hon. GLENN T. SEABORG, Chairman, Atomic Energy Commission, Washington, D.O.

DEAR DR. SEABORG : At its 44th meeting, October 4-6, 1962, the Advisory Committee on Reactor Safeguards considered the site proposed by Nuclear Fuel Services, Inc., for a plant to process reactor fuels. The committee had the benefit of discussion with representatives of the applicant and members of the AEC staff, of the reports listed below, and of a visit by a subcommittee to the site,

The site is located in a sparsely populated area in Cattaraugus County, N.Y., about 30 miles southeast of Buffalo. The proposed plant has a nominal capacity of 1,000 kilograms per day of nuclear fuels of various types. It will employ a number of chemical processes, most of which have already been used on a substantial scale at other locations. The committee has not reviewed these processes or the equipment design in detail.

The applicant estimates that for typical operating conditions none of the general public will be exposed to an integrated radiation dose in excess of the limits of 10 CFR part 20. The most severe accident postulated would not cause exposures in excess of the guides suggested in 10 CFR part 100. While these limits would not be exceeded, even if releases several times those estimated by the applicant were to occur, such increases in load is not visualized.

It is the opinion of the Advisory Committee on Reactor Safeguards that the site selected may be considered as suitable for a fuel reprocessing plant of the type and capacity proposed with reasonable assurance that it may be operated without undue hazard to the health and safety of the public. Mr, K. R. Osborn did not participate in the discussions of this project. Sincerely yours,

F. A. GIFFORD, Jr. Chairman. References:

1. Application for Construction Permit and License for a Spent Fuel Processing Plant, Part A-General Information, dated July 25, 1962.

2. Safety Analysis, Spent Fuel Processing Plant, Part B-Volume I and II, dated July 1962.

3. Letter from Scharfeld, Bechhoefer, Baron & Stambler, dated September 7, 1962, transmitting additional information to Part B.

ADVISORY COMMITTEE ON REACTOR SAFEGUARDS,

ATOMIC ENERGY COMMISSION,

Washington, D.C., December 26, 1962. Subject: Report on Nuclear Fuel Services, Inc. Hon. GLENN T. SEABORG, Chairman, Atomic Energy Commission, Washington, D.O.

DEAR DR. SEABORG : At its 45th meeting on December 13–15, 1962, at Oak Ridge, Tenn., the Advisory Committee on Reactor Safeguards considered the nuclear fuel processing plant proposed by Nuclear Fuel Services, Inc., to be constructed at the State-owned, Springville site located southwest of Buffalo, N.Y. In its letter of October 11, 1962, the Committee commented on the suitability of the site for the proposed operations. The Committee had the benefit of oral presentations by representatives of Nuclear Fuel Services, Inc., Bechtel Corp., the AEC regulatory staff and its consultant, and of the reports listed.

The process to be used is a batch dissolution of fuel elements which are usually chopped into small pieces. The plant will be designed to handle a nominal throughput of 1,000 kilograms of uranium per day. A variety of types of fuel with varying exposure time histories are to be processed, the upper limit of which is approximatley represented by the following parameters :

Burnup: 20,000 mwd/ton.
Specific power: 27.5 mw/ton.
Irradiation time: 2 years.
Load factor: 85 percent.

Cooling time: 150 days. Similar chemical processing operations have been conducted on a production basis at various Commission-owned plants for several years. A prototype fuel element chopping operation has been carried on at Oak Ridge for about 3 years. This experience furnishes an adequate basis for plant design.

The Committee believes that this plant can be designed and constructed with reasonable assurance that it may be operated without undue hazard to the health and safety of the public. Mr. K. R. Osborn did not participate in the discussions of this project. Sincerely yours,

F. A. GIFFORD, Jr., Chairman. References:

1. Application for Construction Permit and License for a Spent Fuel Processing Plant, Part A--General Information, dated July 25, 1962.

2. Safety Analysis, Spent Fuel Processing Plant, Part B Volume I and Volume II, dated July 1962.

3. Letter from Scharfeld, Bechhoefer, Baron & Stambler, dated September 7, 1962, transmitting additional information to Part B.

4. Application for Construction Permit and License for a Spent Fuel Processing Plant, Part B-Safety Analysis, Amendment No. 1, dated October 12, 1962.

5. Letter from Scharfeld, Bechhoefer, Baron & Stambler, dated October 24, 1962, transmitting seven drawings referred to in Amendment No. 1.

6. Amendment No. 2 dated November 23, 1962 to Application for Construction Permit and License.

APPENDIX 7

ADDITIONAL MATERIAL FURNISHED FOR THE RECORD BY NUCLEAR FUEL SERVICES, INC.

Before the

U.S. ATOMIC ENERGY COMMISSION

Washington, D.C.

AEC Docket No. 50-201

IN RE MATTER OF THE APPLICATION OF NUCLEAR FUEL SERVICES, INC., FOR A SPENT

FUEL PROCESSING PLANT

TECHNICAL STATEMENT IN SUPPORT OF APPLICATION FOR CONSTRUCTION PERMIT CONTAINING A SUMMARY DESCRIPTION OF THE FACILITY AND THE FEATURES IMPORTANT TO SAFETY

1. GENERAL DESCRIPTION OF THE PROJECT

In accordance with procedures of the Atomic Energy Commission, Nuclear Fuel Services, Inc. (NFS) herewith submits this technical statement containing a summary description of the proposed facility and the features important to safety in support of its pending application with the AEC for a construction permit. NFS is a corporation, all of the stock of which is owned by the W. R. Grace & Co. (78 percent) and American Machine & Foundry Co. (22 percent). The requested authorization would cover the construction and operation of a chemical plant for the reprocessing of the spent fuel from nuclear reactors. The NFS plant is to be built on land owned by and leased from the State of

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