The study attempts to develop an in-depth understanding of the behavior of open wells in the region through sensitivity analysis of the aquifer parameters and its method of pumping test design. The estimation of groundwater balance and flow paths requires appropriate aquifer parameters, representing the study domain.
In hard rock regions these parameters are highly heterogeneous and anisotropic. Even a very fine network of lithologs and monitoring wells is not sufficient to define the spatial variation of these parameters. In addition to that, complete uncertainty prevails regarding selection of suitable method for the analysis of pumping and recovery test data.
In the study pumping and recovery test data of six wells in Anantapur district have been analyzed. The problem was of deciding the final flow and storage parameters, which can be used for flow and storage analysis. Three methods of analysis of pumping phase data were used and were based upon same flow conditions with various corrections.
Overall there is a certain degree of matching well-wise of the values of transmissivity estimated by Theis and Popodopulus-Cooper method. There is no matching in the values of storativity calculated by all the three methods for pumping phase analysis. However, storage parameters by Popodopulus and Cooper method gives a more reliable storativity value for confined aquifers.
In the recovery phase only flow parameters were estimated. All the methods used have different approaches but have produced comparable results. Therefore, it makes sense to depend more on the recovery phase data analysis than the pumping phase data analysis for open wells in hard rocks.
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