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Ethan Allen Cross (Colorado State Teachers College), Greeley, Colorado, USA, letter, 1934 August 23, to Hamlin Garland (The Century Club), 7 West 43rd Street, New York, New York, USA. "A good many years ago you gave me permission to use your story…" -- first line.

Hamlin Garland, letter, 1914 February 20, to Ethan Allen Cross. "I am inclined to consider favorably a return engagement at Greeley, Colorado…" -- first line.

Hamlin Garland, letter, 1914 March 11, to Ethan Allen Cross (State Normal College), Greeley, Colorado, USA. "As I understand it, President Snyder is asking for five addresses and five informal talks…" -- first line.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2015., Cataloged from PDF version of thesis., Includes bibliographical references (pages 223-240)., This work advances the concept of deep borehole disposal (DBD), where spent nuclear fuel (SNF) is isolated at depths of several km in basement rock. Improvements to the engineered components of the DBD concept (e.g., plug, canister, and fill materials) are presented. Reference site parameters and models for radionuclide transport, dose, and cost are developed and coupled to optimize DBD design. A conservative and analytical representation of thermal expansion flow gives vertical velocities of fluids vs. time (and the results are compared against numerical models). When fluid breakthrough occurs rapidly, the chemical transport model is necessary to calculate radionuclide concentrations along the flow path to the surface. The model derived here incorporates conservative assumptions, including instantaneous dissolution of the SNF, high solubility, low sorption, no aquifer or isotopic dilution, and a host rock matrix that is saturated (at a steady state profile) for each radionuclide. For radionuclides that do not decay rapidly, sorb, or reach solubility limitations (e.g., 1-129), molecular diffusion in the host rock (transverse to the flow path) is the primary loss mechanism. The first design basis failure mode (DB 1) assumes the primary flow path is a 1.2 m diameter region with 100x higher permeability than the surrounding rock, while DB2 assumes a 0.1 mm diameter fracture. For the limiting design basis (DB 1), borehole repository design is constrained (via dose limits) by the areal loading of SNF (MTHM/km2 ), which increases linearly with disposal depth. In the final portion of the thesis, total costs (including drilling, site characterization, and emplacement) are minimized ($/kgHM) while borehole depth, disposal zone length, and borehole spacing are varied subject to the performance (maximum dose) constraint. Accounting for a large uncertainty in costs, the optimal design generally lies at the minimum specified disposal depth (assumed to be 1200 in), with disposal, by Ethan Allen Bates., Ph. D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2011., Cataloged from PDF version of thesis., Includes bibliographical references (p. 85-88)., Disposal of high-level nuclear waste in deep boreholes drilled into crystalline bedrock (i.e., "granite") is an interesting repository alternative of long standing. Work at MIT over the past two decades, and more recently in collaboration with the Sandia National Laboratory, has examined a broad spectrum of design aspects associated with this approach. For emplacement, past reports suggest using steel cables to lower each canister into the borehole. This process would require many years to complete and precise control to safely lower the canisters thousands of meters. The current study evaluated a simple, rapid, "passive" procedure for emplacement of canisters in a deep borehole: free-fall release into a water-flooded borehole. The project involves both analytic modeling and 1/5th scale experiments on a laboratory mockup. Experiments showed good agreement and validated the model. Depending on the inputs used for the mass and dimensions of the full scale canister and the viscosity of water, the model predicted terminal velocities of 2.4-2.6 m/s (4.5-5.8 mph). Further experiments showed that this could be reduced by 50% by making the surface hydraulically rough. Based on these predictions and a structural analysis, there seems to be little risk of damage when a canister reaches the bottom of the borehole or impacts the stack of previously loaded canisters. For reference, dropping the canister in air from a height of only 0.3 m (1 ft) would result in an impact velocity of 2.44 m/s. Cost estimates for the conventional drill string based method were developed, and the drop-in method was concluded to reduce emplacement costs and time by a minimum of 70%, down to $700,000 per borehole. It is concluded that a simple drop-in procedure deserves serious consideration for adoption as a standard procedure for borehole loading., by Ethan Allen Bates., S.M.