This paper presents a method of estimating spatial distributions of the aquifer transmissivity and the groundwater head which are disturbed by random noises.
The Kalman filtering theory is applied to an equation of motion of the two-dimensional groundwater flow and to the autoregressive model that describes the spatial structure of the transmissivity. These two system equations are coupled to account for an influence of the groundwater movement in the estimation of the transmissivity.
The observed values of the groundwater head and the transmissivity, which include measuring errors, can be effectively used in the Kalman filtering algorithm.
In order to confirm the validity of the present method, an experiment is carried out for a one-dimensional aquifer model.

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A transient dispersion-convection equation, which appears in the problems of heat and mass transport in flowing groundwater, is solved numerically by means of a finite element method coupled with the method of characteristics. Numerical errors such as numerical dispersion and oscillation, generally encountered in solving dispersion-convection equations numerically, can be eliminated by using the proposed method. Numerical solutions by the characteristic finite element method showed good agreement with analytical ones.

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The Hashirimizu spring had been utilized for the city water supply of Yokosuka City, since one hundred years ago.
“ Where the spring water come from ?” was a mysterious question for a long time.
From 1976 to 1978, we could chtllenge to elucidate the semieternal puzzle by means of thermal-infrared imagery method (on air), measurement of temperature of sea-water (by sea), gammaray survey (carborn), geological test boring, pumping water well test and others.
It was presumed that the origin of the spring water would be came up from plural brecciated rock zones in Neogene formation.
The brecciated zones are extending from the western coast to the eastern coast of Miura peninsula and accordingly the spring has distinct characteristics in constant flowing quantity and water quality all the year round, in spite of its too-small catchment-area compared with yielding amounts from the spring.
Next, we could understand that, the yield of the spring had only 300 cubic meters a day or a little more as a surplus, beyond the daily yield of 2,700 cubic meters a day. This matters was actually certified by installation of a horizontal water collector with radially installed strainers at a suitable site to get superfluous ground-water.

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