In order to improve the efficiency of the hydraulic conveying of snow by a pump-pipeline system, techniques to measure and control the in-situ concentration of snow/water mixture flowing in a pipe were developed, and the optimum condition was discussed on the basis of high concentration data obtained by applying these techniques.
The volume snow fraction in pipe, C, was determined by the in-situ concentration meter devised here in the range of C=030% within 3% error. Using the devised water-separator, an instrument to extract water from the mixture flowing in a pipe, a high concentration flow up to C=35% was attained. This upper limit of C was caused by the choking of the water separator with a densified snow cluster.
When C was greater than a critical value, C_cr, the pressure loss in a horizontal pipe increased rapidly with C, deviating from the value predicted by the method proposed so far. Although C_cr depends slightly on the flow velocity, roughly speaking, C_cr≥25% for the granulated snow and C_cr≥22% for the fresh snow.
It was concluded that the power loss was minimized when C=C_cr under the condition that the mass flow-rate of snow and the conveying distance were given.

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The wind speed at the surface of snow cover was parameterized as functions of the density of snow cover and the size of snow particles. The critical wind speed to cause drifting snow decreases with decreasing density of snow cover and size of snow particles. This means that fresh snow conditions are easy to occur drifting snow.
A method was explained for estimating surface wind speed over a complex terrain with an inhomogeneous aerodynamic roughness.

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In this study, the author suggests a new method for evaluating the frost-susceptibility of soils, based on the thermal condition of soil-free ice lens formation. Through a series of laboratory freezing tests, the condition is determined by the relationship of a temperature gradient across the unfrozen part of a soil specimen with a temperature gradient across the frozen part of a specimen. In the tests, the results indicated that the temperature gradients were in proportion to each other. The constant of the proportionality to characterize the frost-susceptibility of a given soil, is expressed as a function of the water intake efficiency at the freezing front and the hydraulic conductivity in the unfrozen part of a specimen. Using the value of the constant, the frost-susceptibilities of three different soils were quantitatively compared.

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