The distribution of evaporation rate on some rock walls of drifts in two mines, i. e., the Stripa Mine, Sweden and the Tono Mine, Japan. Although the relative humidity in the drifts of the Stripa Mine was lower than 85%, the humidity in the drifts of the Tono Mine was higher than 95%. The obtained results were as follows;
(1) The evaporation rate could be well measured even under the high humidity condition.
(2) Considerable amount of water could evaporate from a dried fracture.
(3) Evaporation rate spatially changed along a fracture.
(4) The evaporation rate might be identical to the groundwater discharge comming through a rock mass if the permeability of rock mass was low.
It was clearly found that the technique of the evaporation measurement was quite useful for mapping the groundwater discharge on a tunnel wall of the low permeable rock mass.

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Electrical prospecting method is traditionally used to obtain an information of geological profile, as one of geophysical prospecting methods for hydrogeological survey. However, recently, we need to develop a new technique which provides a moving profile of resistivity due to the groundwater flow.
A new technique, in which movement of an electrolyte tracer is obtained by means of resistivity measurements and the feature of the tracer movement beneath a survey line is visually displayed, is demonstrated in this paper. Sodium chloride is used as a tracer. The effectiveness of this method is ensured with the result of borehole loggings.

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If an “Angle Line” defines the straight Iine from the center of a projection net to the middle point of great circle (arc) which represents the dip of the planar direction on an equal-angle projection net, the dip of geological separation is indicated by the Angle Line as well as by great circle.
The “Angle Line”, may enable us to classify the rock slopes ultimately into six types: Dip Slope Type I (φ>β), Dip Slope Type II (α>β>φ), Dip Slope Type III (β>α), Scarp Slope Type I (φ>90-β), Scarp Slope Type II (α>90-β>φ), Scarp Slope Type III (90-β>α), Where, α=the dip of the rock slope, β=the dip of main geological separation in the rock slope, φ=the frictional angle of sliding.
My field reseach on the rock slopes along the Kuji Glen evidently shows that it is only the rock slopes of our Dip Slope Type II that have scars of large failures on them. This proves that classification of rock slopes on the basis of the Angle Line is effective for preventing rock slope failures.

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This paper treats of engineerisg geological description on distribution and relationship of geologic units. A concept of “foreseeability” is introduced. This is defined to the extent of predictive certainty around a point or a line of examination.
From the viewpoint “foreseeability”, necessity of which the pattern of distribution of geologic units is classified rises up. The classification proposed is as follows.
A. Syngenetic structures
A-1 Homogeneous body
A-2 Layered body
a. well continued
b. poorly continued
A-3 Heterogeneous body
a. chaotic (block-in-matrix)
b. heterogeneity of grain size or composition
B. Postgenetic structures
B-1 Deformation of geologic body
a. fault
b. folding
B-2 Relationship among geologic units
a. unconformity
b. fluidal intrusion or injection
The classification enables us to describe the controlling factors of the foreseeability and to evaluate the degree of foreseeability.

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