In contrast to the RAMEY model, the model approach after MOENCH takes into consideration a skin zone of limited extent around the well (finite skin). Accordingly, this skin zone possesses a radius (measured from the borehole centre), a permeability and a storage coefficient.
Beside the Stehfest points and the type curve parameters, you must tell the program
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the ratio of the permeability of the aquifer to the permeability of the skin zone,
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the ratio of the storage coefficient of the skin zone to the storage coefficient of the aquifer and
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the ratio of the radius of the skin zone to that of the borehole or the well
Here, too, it is advisable to carefully consider the configuration for the type curve calculation. For example, for a well in a relatively impermeable rock, the permeable filter gravel fill can be taken into consideration as a skin zone.
All further steps have already been described.