The main contents introduced in this paper are as followings.1. About mechanism of this method.
We can consider the deep well whose strainers are set in unconfined aquifer and confined aquifer, as the water way which connects confined water and unconfined water (the concidered well is such as combination type of collective well (radial collector well) and normal deep well.
In such area as confined water head is depressed excessively, unconfined water flows down to confined aquifers through above mentioned well.2. Abut the geological conditions of the investigated area.
In the northern area of the Musashino terrace (Kiyose, Niiza, Wako etc), next geological sequence is recognized.
These strata incline toward northeast with dip of 1/70 (lower)∼ 1/180(upper) and we can recognize buried valley on the Miura group and on the Lower Tokyo formation.
These conditions are desirable for this method.3. About hydrogeological condition.
From aquifer test it is clarified that unconfined aquifer and confined aquifer have relatively large transmissibility.4. About the one example.
By the underwater T. V camera set in a deep well (Oizumi, Nerima, Tokyo) and records of water level fluctuations, the fact that unconfined water flows out from its strainer and flows in confined aquifer is observed and we examined quantitatively natural recharge volume.

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The Alluvial ground undulates incessantly at Tegata in the Akita Oil field in the North Japan. The tiltings are composed of (1) annual cyclic variation, (2) progressive inclination to ENE, and (3) short period seesaw movements.
The annual cyclic variation, to incline relatively to SE in winter and to reduce the angle in summer almost regularly, is related with the fluctuation of free groundwater table. The inclination increases in general as the water table gets higher. The two are especially intimate in winter. It may de due to both the reduction of permeability and the variations of permeability by temperature at the lower temperatures than probably 12° C.
The progressive inclination to ENE is certainly related with the movements of the Miocene silty bed rocks.
The short period undulation reflects surely the movements of the bed rocks, and related to the occurrences of earthquakes and the volcanic eruption of Mt. Koma in 1970.
In the case, the inclination increases to some extent, the groundwater generally gets higher in resistivity and becomes lower in Redox potential. Resistivity, Redox potential and pH sometimes vary to large degree even without remarkable variation of inclination. Although the mutual relations of tilting, resistivity, Redox potential and pH are complicate, their variations suggest the squeezing-out of groundwater by the crustal lateral pressure, occasionally relating to the occurrences of earthquake.

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The writer investigated about the cause which the value in the physical property differed with density logs and lavoratory test of core samples.
Moreover, by putting together the data which Dr. BREDEHOEFT, Dr. JONES and Dr. WENZEL researched, he found a method for discriminating aquifer of Quaternary by density logging.

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By continuous and excess pumping of a well, storage of the confined aquifer concerned decreases year by year, and the resulting form is like the decline of piestic level of ground-water. Under such a situation, the only index to evaluate the storage in decreasing may be“ Coefficient of Storage” of the aquifer, which is treated as a certain constant in Theis' Non-equilibrium Formula. Assuming the coefficient is variable, the writer proposed a practical method to analyse the yearly decrease of ground-water storage of aquifer, having been discharged for a long term counted in unit of month or year.

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